Projects - User contributions [en]

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T17:47:39Z

A1722328: /* Design Aluminium Core */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

The modelling of magnetic energy conversion was important to many projects such as a project that involves magnetic energy conversion. The magnetic energy conversion was widely used in many areas like renewable energy, future energy, and even in autonomous systems nowadays. Besides, many applications involves with these losses like eddy current losses was currently being used as a braking system for most of the train. So, this project will be beneficial to all project that involves magnetic energy conversion. This was because one of the main objectives of this project was to study the power losses when magnetic energy conversion happens. The new knowledge that this project will bring to the people was how to examine the losses when doing an experiment involving magnetic energy conversion and how to reduce it to its smallest value. Besides, this project group needs to have new knowledge more on ferromagnetism, the effects of nonlinearities, and the separation of the power losses. Not to forget, this project needs to have new knowledge on how to handle the Gibbs effect, as this project will be using a Complex
Fourier Analysis and Inverse Complex Fourier Analysis in a Matlab where the Gibbs effect is a natural phenomenon that exists when applying a Fourier Analysis.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [1].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [1].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [2].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [2]. Chen and Pillay in [3] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [4] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [4] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [5] which represents eddy current losses in soft magnetic materials.

Bertotti in [6] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E's aluminium.png|frame|center|E's Aluminium design]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure above shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

=== Design Iron Core ===

For the next design, the air core choke was replaced with an iron core choke to perform the same method of measurements and analysis that was done for the air-core choke. None of the circuit components were replaced to ensure the exact parameters that will be included in the measurements of the iron core choke. The iron core choke was obtained from the previous research project group.

[[File: Bottom view iron core.png|frame|center|Bottom view of the iron core choke]]
[[File: Side view of iron core.png|frame|center|side view of the iron core choke]]
[[File:Iron core model.png|frame|center|iron core model]]

== Results ==

=== Choke Air-core ===
[[File:Parameters air choke.png|frame|center|Waveform for air core parameter]]

Those waveforms were the result after the bug found during the measurement has been fixed.

=== BH curve air core ===

[[File:BH curve.png|frame|center|B-H curve waveform]]

The number of turns from the coil, the type of the material, and also the flow of the current along the coil affected the magnetic strength of the electromagnet. The B-H curve is the curve result on the flux density, B against the strength of the magnetic field, H. The ratio of flux density to field strength for ferromagnetic materials is not constant but contrasts with flux density. Since the result was from air core, this ratio was regarded as a constant, and this constant is known as free space permeability.

=== T-test ===

[[File:Inductor.png|frame|center|t-test sample for inductor]]
[[File:T-test graph.png|frame|center|t-distribution graph one tail]]

The result for t critical one tail analysis is stated in the figure above. 1.83311 is the t critical one tail value analysis which means that it is higher than the alpha value, 0.05. The value for the t critical one tail was 1.833 which cuts-off the alpha value at 0.05. The shape of the graph was affected by the value of degrees of freedom. The larger the degrees of freedom, the smaller the tails distribution area. Since the t critical one tail value is larger than the alpha value, thus the null hypothesis is accepted which there was no difference between both data.

=== Iron-Core ===

[[File:50V iron core.png|frame|center|Error voltage waveform on 50V]]

These waveforms were the reaction between the component inside the choke and the type of core material being used. These waveform results were affected by the value of the running voltage.

=== Aluminium-core Simulation ===

[[File:Flux density.png|frame|center|flux density aluminium core]]
[[File:Magnetising core.png|thumb|Magnetising force of the aluminium core]]

Both figures showed an identical waveform in which a sudden spike occurred at the 20mm length. This is due to the result that has been exceeding the length of the core at 20mm. when the waveform runs above the length of the core, a sudden spike on the flux density will be formed.

== Conclusion ==

For the conclusion. This thesis focuses on the experiment that is being conducted throughout the period of this research project and the findings that were obtained with it. Studying the nonlinearities element of an inductor choke with a different type of material promotes the urge to obtain a better understanding of the properties of the magnetization and the electrical parameters that were being presented in the measurement, calculations, and the waveforms that were plotted.

All the calibration process on the tools and the main components for the research project is completed and the offsets of the that occurred have been obtained and taken into account in the calculations. The hypothesis testing that was conducted strengthens the level of comparison in two different methods of measuring the parameters in which the MATLAB calculations and the LUTRON LCR meter have been accepted as the there differences between the results are not significant and with the acceptance range.

The usage of Picoscope and MATLAB in the research project has been considered a successful approach as it provides required results in the measurement of the air core inductor choke and the iron core inductor choke.
The magnetic properties of the air core inductor choke were obtained by creating the magnetisation curve which proves to be linear as the air core has no nonlinearities magnetic properties on it.

The simulation task that replaced the final measurement of the aluminium due to the unavoidable circumstances has been completed and analysed using the Ansys Maxwell software.

== References ==

[1] C. Kittel, Introduction to solid state physics, 5th ed. New York: Wiley, 1976.

[2] J. P. A. Bastos, Magnetic materials and 3D finite element modeling. 2014.

[3] Y. Chen and P. Pillay, “An improved formula for lamination core loss calculations in machines operating with high frequency and high flux density excitation,” Conf. Rec. - IAS Annu. Meet. (IEEE Ind. Appl. Soc., vol. 2, pp. 759–766, 2002.

[4] L. O. Chua and K. A. Stromsmoe, “Lumped-Circuit Models for Nonlinear Inductors Exhibiting Hysteresis Loops,” IEEE Trans. Circuit Theory, vol. 17, no. 4, pp. 564–574, 1970.

[5] Y. Saito, S. Hayano, and Y. Sakaki, “A parameter representing eddy current loss of soft magnetic materials and its constitutive equation,” J. Appl. Phys., vol. 64, no. 10, pp. 5684–5686, 1988.

[6] G. Bertotti, “Hysteresis in Preisach Systems,” in Hysteresis in Magnetism, 1998.

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T17:29:37Z

A1722328: /* Losses in Ferromagnetic components */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

The modelling of magnetic energy conversion was important to many projects such as a project that involves magnetic energy conversion. The magnetic energy conversion was widely used in many areas like renewable energy, future energy, and even in autonomous systems nowadays. Besides, many applications involves with these losses like eddy current losses was currently being used as a braking system for most of the train. So, this project will be beneficial to all project that involves magnetic energy conversion. This was because one of the main objectives of this project was to study the power losses when magnetic energy conversion happens. The new knowledge that this project will bring to the people was how to examine the losses when doing an experiment involving magnetic energy conversion and how to reduce it to its smallest value. Besides, this project group needs to have new knowledge more on ferromagnetism, the effects of nonlinearities, and the separation of the power losses. Not to forget, this project needs to have new knowledge on how to handle the Gibbs effect, as this project will be using a Complex
Fourier Analysis and Inverse Complex Fourier Analysis in a Matlab where the Gibbs effect is a natural phenomenon that exists when applying a Fourier Analysis.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [1].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [1].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [2].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [2]. Chen and Pillay in [3] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [4] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [4] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [5] which represents eddy current losses in soft magnetic materials.

Bertotti in [6] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E's aluminium.png|frame|center|E's Aluminium design]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure 17 and 18 shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

=== Design Iron Core ===

For the next design, the air core choke was replaced with an iron core choke to perform the same method of measurements and analysis that was done for the air-core choke. None of the circuit components were replaced to ensure the exact parameters that will be included in the measurements of the iron core choke. The iron core choke was obtained from the previous research project group.

[[File: Bottom view iron core.png|frame|center|Bottom view of the iron core choke]]
[[File: Side view of iron core.png|frame|center|side view of the iron core choke]]
[[File:Iron core model.png|frame|center|iron core model]]

== Results ==

=== Choke Air-core ===
[[File:Parameters air choke.png|frame|center|Waveform for air core parameter]]

Those waveforms were the result after the bug found during the measurement has been fixed.

=== BH curve air core ===

[[File:BH curve.png|frame|center|B-H curve waveform]]

The number of turns from the coil, the type of the material, and also the flow of the current along the coil affected the magnetic strength of the electromagnet. The B-H curve is the curve result on the flux density, B against the strength of the magnetic field, H. The ratio of flux density to field strength for ferromagnetic materials is not constant but contrasts with flux density. Since the result was from air core, this ratio was regarded as a constant, and this constant is known as free space permeability.

=== T-test ===

[[File:Inductor.png|frame|center|t-test sample for inductor]]
[[File:T-test graph.png|frame|center|t-distribution graph one tail]]

The result for t critical one tail analysis is stated in the figure above. 1.83311 is the t critical one tail value analysis which means that it is higher than the alpha value, 0.05. The value for the t critical one tail was 1.833 which cuts-off the alpha value at 0.05. The shape of the graph was affected by the value of degrees of freedom. The larger the degrees of freedom, the smaller the tails distribution area. Since the t critical one tail value is larger than the alpha value, thus the null hypothesis is accepted which there was no difference between both data.

=== Iron-Core ===

[[File:50V iron core.png|frame|center|Error voltage waveform on 50V]]

These waveforms were the reaction between the component inside the choke and the type of core material being used. These waveform results were affected by the value of the running voltage.

=== Aluminium-core Simulation ===

[[File:Flux density.png|frame|center|flux density aluminium core]]
[[File:Magnetising core.png|thumb|Magnetising force of the aluminium core]]

Both figures showed an identical waveform in which a sudden spike occurred at the 20mm length. This is due to the result that has been exceeding the length of the core at 20mm. when the waveform runs above the length of the core, a sudden spike on the flux density will be formed.

== Conclusion ==

For the conclusion. This thesis focuses on the experiment that is being conducted throughout the period of this research project and the findings that were obtained with it. Studying the nonlinearities element of an inductor choke with a different type of material promotes the urge to obtain a better understanding of the properties of the magnetization and the electrical parameters that were being presented in the measurement, calculations, and the waveforms that were plotted.

All the calibration process on the tools and the main components for the research project is completed and the offsets of the that occurred have been obtained and taken into account in the calculations. The hypothesis testing that was conducted strengthens the level of comparison in two different methods of measuring the parameters in which the MATLAB calculations and the LUTRON LCR meter have been accepted as the there differences between the results are not significant and with the acceptance range.

The usage of Picoscope and MATLAB in the research project has been considered a successful approach as it provides required results in the measurement of the air core inductor choke and the iron core inductor choke.
The magnetic properties of the air core inductor choke were obtained by creating the magnetisation curve which proves to be linear as the air core has no nonlinearities magnetic properties on it.

The simulation task that replaced the final measurement of the aluminium due to the unavoidable circumstances has been completed and analysed using the Ansys Maxwell software.

== References ==

[1] C. Kittel, Introduction to solid state physics, 5th ed. New York: Wiley, 1976.

[2] J. P. A. Bastos, Magnetic materials and 3D finite element modeling. 2014.

[3] Y. Chen and P. Pillay, “An improved formula for lamination core loss calculations in machines operating with high frequency and high flux density excitation,” Conf. Rec. - IAS Annu. Meet. (IEEE Ind. Appl. Soc., vol. 2, pp. 759–766, 2002.

[4] L. O. Chua and K. A. Stromsmoe, “Lumped-Circuit Models for Nonlinear Inductors Exhibiting Hysteresis Loops,” IEEE Trans. Circuit Theory, vol. 17, no. 4, pp. 564–574, 1970.

[5] Y. Saito, S. Hayano, and Y. Sakaki, “A parameter representing eddy current loss of soft magnetic materials and its constitutive equation,” J. Appl. Phys., vol. 64, no. 10, pp. 5684–5686, 1988.

[6] G. Bertotti, “Hysteresis in Preisach Systems,” in Hysteresis in Magnetism, 1998.

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T17:27:55Z

A1722328: /* References */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

The modelling of magnetic energy conversion was important to many projects such as a project that involves magnetic energy conversion. The magnetic energy conversion was widely used in many areas like renewable energy, future energy, and even in autonomous systems nowadays. Besides, many applications involves with these losses like eddy current losses was currently being used as a braking system for most of the train. So, this project will be beneficial to all project that involves magnetic energy conversion. This was because one of the main objectives of this project was to study the power losses when magnetic energy conversion happens. The new knowledge that this project will bring to the people was how to examine the losses when doing an experiment involving magnetic energy conversion and how to reduce it to its smallest value. Besides, this project group needs to have new knowledge more on ferromagnetism, the effects of nonlinearities, and the separation of the power losses. Not to forget, this project needs to have new knowledge on how to handle the Gibbs effect, as this project will be using a Complex
Fourier Analysis and Inverse Complex Fourier Analysis in a Matlab where the Gibbs effect is a natural phenomenon that exists when applying a Fourier Analysis.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [1].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [1].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [3].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [3]. Chen and Pillay in [4] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [5] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [5] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [6] which represents eddy current losses in soft magnetic materials.

Bertotti in [7] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E's aluminium.png|frame|center|E's Aluminium design]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure 17 and 18 shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

=== Design Iron Core ===

For the next design, the air core choke was replaced with an iron core choke to perform the same method of measurements and analysis that was done for the air-core choke. None of the circuit components were replaced to ensure the exact parameters that will be included in the measurements of the iron core choke. The iron core choke was obtained from the previous research project group.

[[File: Bottom view iron core.png|frame|center|Bottom view of the iron core choke]]
[[File: Side view of iron core.png|frame|center|side view of the iron core choke]]
[[File:Iron core model.png|frame|center|iron core model]]

== Results ==

=== Choke Air-core ===
[[File:Parameters air choke.png|frame|center|Waveform for air core parameter]]

Those waveforms were the result after the bug found during the measurement has been fixed.

=== BH curve air core ===

[[File:BH curve.png|frame|center|B-H curve waveform]]

The number of turns from the coil, the type of the material, and also the flow of the current along the coil affected the magnetic strength of the electromagnet. The B-H curve is the curve result on the flux density, B against the strength of the magnetic field, H. The ratio of flux density to field strength for ferromagnetic materials is not constant but contrasts with flux density. Since the result was from air core, this ratio was regarded as a constant, and this constant is known as free space permeability.

=== T-test ===

[[File:Inductor.png|frame|center|t-test sample for inductor]]
[[File:T-test graph.png|frame|center|t-distribution graph one tail]]

The result for t critical one tail analysis is stated in the figure above. 1.83311 is the t critical one tail value analysis which means that it is higher than the alpha value, 0.05. The value for the t critical one tail was 1.833 which cuts-off the alpha value at 0.05. The shape of the graph was affected by the value of degrees of freedom. The larger the degrees of freedom, the smaller the tails distribution area. Since the t critical one tail value is larger than the alpha value, thus the null hypothesis is accepted which there was no difference between both data.

=== Iron-Core ===

[[File:50V iron core.png|frame|center|Error voltage waveform on 50V]]

These waveforms were the reaction between the component inside the choke and the type of core material being used. These waveform results were affected by the value of the running voltage.

=== Aluminium-core Simulation ===

[[File:Flux density.png|frame|center|flux density aluminium core]]
[[File:Magnetising core.png|thumb|Magnetising force of the aluminium core]]

Both figures showed an identical waveform in which a sudden spike occurred at the 20mm length. This is due to the result that has been exceeding the length of the core at 20mm. when the waveform runs above the length of the core, a sudden spike on the flux density will be formed.

== Conclusion ==

For the conclusion. This thesis focuses on the experiment that is being conducted throughout the period of this research project and the findings that were obtained with it. Studying the nonlinearities element of an inductor choke with a different type of material promotes the urge to obtain a better understanding of the properties of the magnetization and the electrical parameters that were being presented in the measurement, calculations, and the waveforms that were plotted.

All the calibration process on the tools and the main components for the research project is completed and the offsets of the that occurred have been obtained and taken into account in the calculations. The hypothesis testing that was conducted strengthens the level of comparison in two different methods of measuring the parameters in which the MATLAB calculations and the LUTRON LCR meter have been accepted as the there differences between the results are not significant and with the acceptance range.

The usage of Picoscope and MATLAB in the research project has been considered a successful approach as it provides required results in the measurement of the air core inductor choke and the iron core inductor choke.
The magnetic properties of the air core inductor choke were obtained by creating the magnetisation curve which proves to be linear as the air core has no nonlinearities magnetic properties on it.

The simulation task that replaced the final measurement of the aluminium due to the unavoidable circumstances has been completed and analysed using the Ansys Maxwell software.

== References ==

[1] C. Kittel, Introduction to solid state physics, 5th ed. New York: Wiley, 1976.

[2] J. P. A. Bastos, Magnetic materials and 3D finite element modeling. 2014.

[3] Y. Chen and P. Pillay, “An improved formula for lamination core loss calculations in machines operating with high frequency and high flux density excitation,” Conf. Rec. - IAS Annu. Meet. (IEEE Ind. Appl. Soc., vol. 2, pp. 759–766, 2002.

[4] L. O. Chua and K. A. Stromsmoe, “Lumped-Circuit Models for Nonlinear Inductors Exhibiting Hysteresis Loops,” IEEE Trans. Circuit Theory, vol. 17, no. 4, pp. 564–574, 1970.

[5] Y. Saito, S. Hayano, and Y. Sakaki, “A parameter representing eddy current loss of soft magnetic materials and its constitutive equation,” J. Appl. Phys., vol. 64, no. 10, pp. 5684–5686, 1988.

[6] G. Bertotti, “Hysteresis in Preisach Systems,” in Hysteresis in Magnetism, 1998.

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T17:24:40Z

A1722328: /* Ferromagnetism */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

The modelling of magnetic energy conversion was important to many projects such as a project that involves magnetic energy conversion. The magnetic energy conversion was widely used in many areas like renewable energy, future energy, and even in autonomous systems nowadays. Besides, many applications involves with these losses like eddy current losses was currently being used as a braking system for most of the train. So, this project will be beneficial to all project that involves magnetic energy conversion. This was because one of the main objectives of this project was to study the power losses when magnetic energy conversion happens. The new knowledge that this project will bring to the people was how to examine the losses when doing an experiment involving magnetic energy conversion and how to reduce it to its smallest value. Besides, this project group needs to have new knowledge more on ferromagnetism, the effects of nonlinearities, and the separation of the power losses. Not to forget, this project needs to have new knowledge on how to handle the Gibbs effect, as this project will be using a Complex
Fourier Analysis and Inverse Complex Fourier Analysis in a Matlab where the Gibbs effect is a natural phenomenon that exists when applying a Fourier Analysis.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [1].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [1].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [3].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [3]. Chen and Pillay in [4] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [5] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [5] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [6] which represents eddy current losses in soft magnetic materials.

Bertotti in [7] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E's aluminium.png|frame|center|E's Aluminium design]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure 17 and 18 shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

=== Design Iron Core ===

For the next design, the air core choke was replaced with an iron core choke to perform the same method of measurements and analysis that was done for the air-core choke. None of the circuit components were replaced to ensure the exact parameters that will be included in the measurements of the iron core choke. The iron core choke was obtained from the previous research project group.

[[File: Bottom view iron core.png|frame|center|Bottom view of the iron core choke]]
[[File: Side view of iron core.png|frame|center|side view of the iron core choke]]
[[File:Iron core model.png|frame|center|iron core model]]

== Results ==

=== Choke Air-core ===
[[File:Parameters air choke.png|frame|center|Waveform for air core parameter]]

Those waveforms were the result after the bug found during the measurement has been fixed.

=== BH curve air core ===

[[File:BH curve.png|frame|center|B-H curve waveform]]

The number of turns from the coil, the type of the material, and also the flow of the current along the coil affected the magnetic strength of the electromagnet. The B-H curve is the curve result on the flux density, B against the strength of the magnetic field, H. The ratio of flux density to field strength for ferromagnetic materials is not constant but contrasts with flux density. Since the result was from air core, this ratio was regarded as a constant, and this constant is known as free space permeability.

=== T-test ===

[[File:Inductor.png|frame|center|t-test sample for inductor]]
[[File:T-test graph.png|frame|center|t-distribution graph one tail]]

The result for t critical one tail analysis is stated in the figure above. 1.83311 is the t critical one tail value analysis which means that it is higher than the alpha value, 0.05. The value for the t critical one tail was 1.833 which cuts-off the alpha value at 0.05. The shape of the graph was affected by the value of degrees of freedom. The larger the degrees of freedom, the smaller the tails distribution area. Since the t critical one tail value is larger than the alpha value, thus the null hypothesis is accepted which there was no difference between both data.

=== Iron-Core ===

[[File:50V iron core.png|frame|center|Error voltage waveform on 50V]]

These waveforms were the reaction between the component inside the choke and the type of core material being used. These waveform results were affected by the value of the running voltage.

=== Aluminium-core Simulation ===

[[File:Flux density.png|frame|center|flux density aluminium core]]
[[File:Magnetising core.png|thumb|Magnetising force of the aluminium core]]

Both figures showed an identical waveform in which a sudden spike occurred at the 20mm length. This is due to the result that has been exceeding the length of the core at 20mm. when the waveform runs above the length of the core, a sudden spike on the flux density will be formed.

== Conclusion ==

For the conclusion. This thesis focuses on the experiment that is being conducted throughout the period of this research project and the findings that were obtained with it. Studying the nonlinearities element of an inductor choke with a different type of material promotes the urge to obtain a better understanding of the properties of the magnetization and the electrical parameters that were being presented in the measurement, calculations, and the waveforms that were plotted.

All the calibration process on the tools and the main components for the research project is completed and the offsets of the that occurred have been obtained and taken into account in the calculations. The hypothesis testing that was conducted strengthens the level of comparison in two different methods of measuring the parameters in which the MATLAB calculations and the LUTRON LCR meter have been accepted as the there differences between the results are not significant and with the acceptance range.

The usage of Picoscope and MATLAB in the research project has been considered a successful approach as it provides required results in the measurement of the air core inductor choke and the iron core inductor choke.
The magnetic properties of the air core inductor choke were obtained by creating the magnetisation curve which proves to be linear as the air core has no nonlinearities magnetic properties on it.

The simulation task that replaced the final measurement of the aluminium due to the unavoidable circumstances has been completed and analysed using the Ansys Maxwell software.

== References ==

[1] C. Kittel, Introduction to solid state physics, 5th ed. New York: Wiley, 1976.

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T17:23:16Z

A1722328: /* References */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

The modelling of magnetic energy conversion was important to many projects such as a project that involves magnetic energy conversion. The magnetic energy conversion was widely used in many areas like renewable energy, future energy, and even in autonomous systems nowadays. Besides, many applications involves with these losses like eddy current losses was currently being used as a braking system for most of the train. So, this project will be beneficial to all project that involves magnetic energy conversion. This was because one of the main objectives of this project was to study the power losses when magnetic energy conversion happens. The new knowledge that this project will bring to the people was how to examine the losses when doing an experiment involving magnetic energy conversion and how to reduce it to its smallest value. Besides, this project group needs to have new knowledge more on ferromagnetism, the effects of nonlinearities, and the separation of the power losses. Not to forget, this project needs to have new knowledge on how to handle the Gibbs effect, as this project will be using a Complex
Fourier Analysis and Inverse Complex Fourier Analysis in a Matlab where the Gibbs effect is a natural phenomenon that exists when applying a Fourier Analysis.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [4].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [4].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [3].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [3]. Chen and Pillay in [4] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [5] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [5] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [6] which represents eddy current losses in soft magnetic materials.

Bertotti in [7] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E's aluminium.png|frame|center|E's Aluminium design]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure 17 and 18 shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

=== Design Iron Core ===

For the next design, the air core choke was replaced with an iron core choke to perform the same method of measurements and analysis that was done for the air-core choke. None of the circuit components were replaced to ensure the exact parameters that will be included in the measurements of the iron core choke. The iron core choke was obtained from the previous research project group.

[[File: Bottom view iron core.png|frame|center|Bottom view of the iron core choke]]
[[File: Side view of iron core.png|frame|center|side view of the iron core choke]]
[[File:Iron core model.png|frame|center|iron core model]]

== Results ==

=== Choke Air-core ===
[[File:Parameters air choke.png|frame|center|Waveform for air core parameter]]

Those waveforms were the result after the bug found during the measurement has been fixed.

=== BH curve air core ===

[[File:BH curve.png|frame|center|B-H curve waveform]]

The number of turns from the coil, the type of the material, and also the flow of the current along the coil affected the magnetic strength of the electromagnet. The B-H curve is the curve result on the flux density, B against the strength of the magnetic field, H. The ratio of flux density to field strength for ferromagnetic materials is not constant but contrasts with flux density. Since the result was from air core, this ratio was regarded as a constant, and this constant is known as free space permeability.

=== T-test ===

[[File:Inductor.png|frame|center|t-test sample for inductor]]
[[File:T-test graph.png|frame|center|t-distribution graph one tail]]

The result for t critical one tail analysis is stated in the figure above. 1.83311 is the t critical one tail value analysis which means that it is higher than the alpha value, 0.05. The value for the t critical one tail was 1.833 which cuts-off the alpha value at 0.05. The shape of the graph was affected by the value of degrees of freedom. The larger the degrees of freedom, the smaller the tails distribution area. Since the t critical one tail value is larger than the alpha value, thus the null hypothesis is accepted which there was no difference between both data.

=== Iron-Core ===

[[File:50V iron core.png|frame|center|Error voltage waveform on 50V]]

These waveforms were the reaction between the component inside the choke and the type of core material being used. These waveform results were affected by the value of the running voltage.

=== Aluminium-core Simulation ===

[[File:Flux density.png|frame|center|flux density aluminium core]]
[[File:Magnetising core.png|thumb|Magnetising force of the aluminium core]]

Both figures showed an identical waveform in which a sudden spike occurred at the 20mm length. This is due to the result that has been exceeding the length of the core at 20mm. when the waveform runs above the length of the core, a sudden spike on the flux density will be formed.

== Conclusion ==

For the conclusion. This thesis focuses on the experiment that is being conducted throughout the period of this research project and the findings that were obtained with it. Studying the nonlinearities element of an inductor choke with a different type of material promotes the urge to obtain a better understanding of the properties of the magnetization and the electrical parameters that were being presented in the measurement, calculations, and the waveforms that were plotted.

All the calibration process on the tools and the main components for the research project is completed and the offsets of the that occurred have been obtained and taken into account in the calculations. The hypothesis testing that was conducted strengthens the level of comparison in two different methods of measuring the parameters in which the MATLAB calculations and the LUTRON LCR meter have been accepted as the there differences between the results are not significant and with the acceptance range.

The usage of Picoscope and MATLAB in the research project has been considered a successful approach as it provides required results in the measurement of the air core inductor choke and the iron core inductor choke.
The magnetic properties of the air core inductor choke were obtained by creating the magnetisation curve which proves to be linear as the air core has no nonlinearities magnetic properties on it.

The simulation task that replaced the final measurement of the aluminium due to the unavoidable circumstances has been completed and analysed using the Ansys Maxwell software.

== References ==

[1] C. Kittel, Introduction to solid state physics, 5th ed. New York: Wiley, 1976.

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T17:22:51Z

A1722328: /* Motivation */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

The modelling of magnetic energy conversion was important to many projects such as a project that involves magnetic energy conversion. The magnetic energy conversion was widely used in many areas like renewable energy, future energy, and even in autonomous systems nowadays. Besides, many applications involves with these losses like eddy current losses was currently being used as a braking system for most of the train. So, this project will be beneficial to all project that involves magnetic energy conversion. This was because one of the main objectives of this project was to study the power losses when magnetic energy conversion happens. The new knowledge that this project will bring to the people was how to examine the losses when doing an experiment involving magnetic energy conversion and how to reduce it to its smallest value. Besides, this project group needs to have new knowledge more on ferromagnetism, the effects of nonlinearities, and the separation of the power losses. Not to forget, this project needs to have new knowledge on how to handle the Gibbs effect, as this project will be using a Complex
Fourier Analysis and Inverse Complex Fourier Analysis in a Matlab where the Gibbs effect is a natural phenomenon that exists when applying a Fourier Analysis.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [4].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [4].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [3].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [3]. Chen and Pillay in [4] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [5] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [5] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [6] which represents eddy current losses in soft magnetic materials.

Bertotti in [7] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E's aluminium.png|frame|center|E's Aluminium design]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure 17 and 18 shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

=== Design Iron Core ===

For the next design, the air core choke was replaced with an iron core choke to perform the same method of measurements and analysis that was done for the air-core choke. None of the circuit components were replaced to ensure the exact parameters that will be included in the measurements of the iron core choke. The iron core choke was obtained from the previous research project group.

[[File: Bottom view iron core.png|frame|center|Bottom view of the iron core choke]]
[[File: Side view of iron core.png|frame|center|side view of the iron core choke]]
[[File:Iron core model.png|frame|center|iron core model]]

== Results ==

=== Choke Air-core ===
[[File:Parameters air choke.png|frame|center|Waveform for air core parameter]]

Those waveforms were the result after the bug found during the measurement has been fixed.

=== BH curve air core ===

[[File:BH curve.png|frame|center|B-H curve waveform]]

The number of turns from the coil, the type of the material, and also the flow of the current along the coil affected the magnetic strength of the electromagnet. The B-H curve is the curve result on the flux density, B against the strength of the magnetic field, H. The ratio of flux density to field strength for ferromagnetic materials is not constant but contrasts with flux density. Since the result was from air core, this ratio was regarded as a constant, and this constant is known as free space permeability.

=== T-test ===

[[File:Inductor.png|frame|center|t-test sample for inductor]]
[[File:T-test graph.png|frame|center|t-distribution graph one tail]]

The result for t critical one tail analysis is stated in the figure above. 1.83311 is the t critical one tail value analysis which means that it is higher than the alpha value, 0.05. The value for the t critical one tail was 1.833 which cuts-off the alpha value at 0.05. The shape of the graph was affected by the value of degrees of freedom. The larger the degrees of freedom, the smaller the tails distribution area. Since the t critical one tail value is larger than the alpha value, thus the null hypothesis is accepted which there was no difference between both data.

=== Iron-Core ===

[[File:50V iron core.png|frame|center|Error voltage waveform on 50V]]

These waveforms were the reaction between the component inside the choke and the type of core material being used. These waveform results were affected by the value of the running voltage.

=== Aluminium-core Simulation ===

[[File:Flux density.png|frame|center|flux density aluminium core]]
[[File:Magnetising core.png|thumb|Magnetising force of the aluminium core]]

Both figures showed an identical waveform in which a sudden spike occurred at the 20mm length. This is due to the result that has been exceeding the length of the core at 20mm. when the waveform runs above the length of the core, a sudden spike on the flux density will be formed.

== Conclusion ==

For the conclusion. This thesis focuses on the experiment that is being conducted throughout the period of this research project and the findings that were obtained with it. Studying the nonlinearities element of an inductor choke with a different type of material promotes the urge to obtain a better understanding of the properties of the magnetization and the electrical parameters that were being presented in the measurement, calculations, and the waveforms that were plotted.

All the calibration process on the tools and the main components for the research project is completed and the offsets of the that occurred have been obtained and taken into account in the calculations. The hypothesis testing that was conducted strengthens the level of comparison in two different methods of measuring the parameters in which the MATLAB calculations and the LUTRON LCR meter have been accepted as the there differences between the results are not significant and with the acceptance range.

The usage of Picoscope and MATLAB in the research project has been considered a successful approach as it provides required results in the measurement of the air core inductor choke and the iron core inductor choke.
The magnetic properties of the air core inductor choke were obtained by creating the magnetisation curve which proves to be linear as the air core has no nonlinearities magnetic properties on it.

The simulation task that replaced the final measurement of the aluminium due to the unavoidable circumstances has been completed and analysed using the Ansys Maxwell software.

== References ==
[1] W. Matizamhuka, “The impact of magnetic materials in renewable energy-related technologies in the 21st century industrial revolution: The case of South Africa,” Adv. Mater. Sci. Eng., vol. 2018, 2018.

[2] W. Yang, L. Guo, Z. Guo, G. Dong, Y. Sui, and Z. Chen, “Improvement of the Magnetic Properties of Nanocrystalline Nd12.3(FeZrNbCu)81.7B6.0 Alloys with Dy Substitutions,” J. Nanomater., vol. 2015, 2015.

[3] Sandoval, David. (2019, November 1). What are the Advantages and Disadvantages of Electromagnetic Energy Power Sources? sciencing.com. Retrieved from https://sciencing.com/advantages-electromagnetic-energy-power-sources-6779004.html

[4] C. Kittel, Introduction to solid state physics, 5th ed. New York: Wiley, 1976.

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T17:19:52Z

A1722328: /* Conclusion */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

Over the years, the development of technology focuses already transposes to renewables as a recent energy source limit. Majority performances of the device will be included magnetic materials to increase the efficiency of devices. Few examples of its application are transportation, electric generator, air conditioning, and telecommunications [1]. The historical development of permanent magnet materials lifetime exceeds a 100-year period [2]. A lot of magnetic materials obtainable, varying from low energy and low-cost ferrites to a pricey and pumped-up RE materials. Magnetic materials are a crucial material to the society because of their ability to handle a group of tasks such as converting mechanical to electrical energy, transmit and distribute electric power, facilitate microwave communications, and provide the basis for data storage systems [2].

Naturally, electrical power will be used by a normal person multiple times. Either by switching on the plug for light or plugging any electrical device into a wall socket. Most of the electricity supplied by electrochemical devices like generators that use hydroelectric power plants or wind turbines. This electromagnetic energy conversion has a benefit relying on the use of an electromechanical device which does not need an external electrical source to generate electrical power. An example of this device is the current (AC) generator [3]. A coil inside the generator is being rotated by rotational mechanical energy which then exposes that coil to change in the magnetic field. Production of alternating current voltage is being induced because of those changes.

AC or direct-current (DC) electrical can be generated by using an electromagnetic energy source. In order to change the alternating current which coming out from power generator into one direction flowing current, or direct current, most DC motors and generators are using a parameter labeled commutator. This project is observing and analysing major nonlinear effects which is more about saturation, eddy currents, and Hysteresis. Due to the importance of this magnetic energy in the current system, observing the losses provide an advantage that can benefit the improvement of magnetic energy conversion production.

The experiment initially focusing on modelling out the magnetic losses in the periodic domain. Fourier method is the main method to identify the losses while applying some Fourier calculation inside a software. MATLAB is the essential software to test out this experiment since it completely satisfies the needs of the project. Once the losses have been identified and the behaviour is understandable, the result can be contributed to improving the efficiency of the magnetic energy conversion in many applications.

Naturally, in this paper, nonlinear parameters will be calculated in a much simpler way. From the result that obtained, the Gibbs effect will be present which is an unwanted natural phenomenon. Certainly, through this experiment, the Gibbs effect in Fourier methods will be reduced to achieve the perfect results.

Apart from it, this experiment is the best way to analyse the losses in nonlinear materials. It will give many students a bigger picture or overview regarding the nonlinear effects on each material. Hence, the behaviour of the losses can be observed and the ideas to resolve it will be generated. In order to look at the eddy current loss, hysteresis loss, and Gibbs effect, the device needs to be run hard enough since it can produce a higher voltage and current which then producing a demanded result.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [4].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [4].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [3].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [3]. Chen and Pillay in [4] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [5] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [5] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [6] which represents eddy current losses in soft magnetic materials.

Bertotti in [7] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E's aluminium.png|frame|center|E's Aluminium design]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure 17 and 18 shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

=== Design Iron Core ===

For the next design, the air core choke was replaced with an iron core choke to perform the same method of measurements and analysis that was done for the air-core choke. None of the circuit components were replaced to ensure the exact parameters that will be included in the measurements of the iron core choke. The iron core choke was obtained from the previous research project group.

[[File: Bottom view iron core.png|frame|center|Bottom view of the iron core choke]]
[[File: Side view of iron core.png|frame|center|side view of the iron core choke]]
[[File:Iron core model.png|frame|center|iron core model]]

== Results ==

=== Choke Air-core ===
[[File:Parameters air choke.png|frame|center|Waveform for air core parameter]]

Those waveforms were the result after the bug found during the measurement has been fixed.

=== BH curve air core ===

[[File:BH curve.png|frame|center|B-H curve waveform]]

The number of turns from the coil, the type of the material, and also the flow of the current along the coil affected the magnetic strength of the electromagnet. The B-H curve is the curve result on the flux density, B against the strength of the magnetic field, H. The ratio of flux density to field strength for ferromagnetic materials is not constant but contrasts with flux density. Since the result was from air core, this ratio was regarded as a constant, and this constant is known as free space permeability.

=== T-test ===

[[File:Inductor.png|frame|center|t-test sample for inductor]]
[[File:T-test graph.png|frame|center|t-distribution graph one tail]]

The result for t critical one tail analysis is stated in the figure above. 1.83311 is the t critical one tail value analysis which means that it is higher than the alpha value, 0.05. The value for the t critical one tail was 1.833 which cuts-off the alpha value at 0.05. The shape of the graph was affected by the value of degrees of freedom. The larger the degrees of freedom, the smaller the tails distribution area. Since the t critical one tail value is larger than the alpha value, thus the null hypothesis is accepted which there was no difference between both data.

=== Iron-Core ===

[[File:50V iron core.png|frame|center|Error voltage waveform on 50V]]

These waveforms were the reaction between the component inside the choke and the type of core material being used. These waveform results were affected by the value of the running voltage.

=== Aluminium-core Simulation ===

[[File:Flux density.png|frame|center|flux density aluminium core]]
[[File:Magnetising core.png|thumb|Magnetising force of the aluminium core]]

Both figures showed an identical waveform in which a sudden spike occurred at the 20mm length. This is due to the result that has been exceeding the length of the core at 20mm. when the waveform runs above the length of the core, a sudden spike on the flux density will be formed.

== Conclusion ==

For the conclusion. This thesis focuses on the experiment that is being conducted throughout the period of this research project and the findings that were obtained with it. Studying the nonlinearities element of an inductor choke with a different type of material promotes the urge to obtain a better understanding of the properties of the magnetization and the electrical parameters that were being presented in the measurement, calculations, and the waveforms that were plotted.

All the calibration process on the tools and the main components for the research project is completed and the offsets of the that occurred have been obtained and taken into account in the calculations. The hypothesis testing that was conducted strengthens the level of comparison in two different methods of measuring the parameters in which the MATLAB calculations and the LUTRON LCR meter have been accepted as the there differences between the results are not significant and with the acceptance range.

The usage of Picoscope and MATLAB in the research project has been considered a successful approach as it provides required results in the measurement of the air core inductor choke and the iron core inductor choke.
The magnetic properties of the air core inductor choke were obtained by creating the magnetisation curve which proves to be linear as the air core has no nonlinearities magnetic properties on it.

The simulation task that replaced the final measurement of the aluminium due to the unavoidable circumstances has been completed and analysed using the Ansys Maxwell software.

== References ==
[1] W. Matizamhuka, “The impact of magnetic materials in renewable energy-related technologies in the 21st century industrial revolution: The case of South Africa,” Adv. Mater. Sci. Eng., vol. 2018, 2018.

[2] W. Yang, L. Guo, Z. Guo, G. Dong, Y. Sui, and Z. Chen, “Improvement of the Magnetic Properties of Nanocrystalline Nd12.3(FeZrNbCu)81.7B6.0 Alloys with Dy Substitutions,” J. Nanomater., vol. 2015, 2015.

[3] Sandoval, David. (2019, November 1). What are the Advantages and Disadvantages of Electromagnetic Energy Power Sources? sciencing.com. Retrieved from https://sciencing.com/advantages-electromagnetic-energy-power-sources-6779004.html

[4] C. Kittel, Introduction to solid state physics, 5th ed. New York: Wiley, 1976.

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T17:18:13Z

A1722328: /* References */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

Over the years, the development of technology focuses already transposes to renewables as a recent energy source limit. Majority performances of the device will be included magnetic materials to increase the efficiency of devices. Few examples of its application are transportation, electric generator, air conditioning, and telecommunications [1]. The historical development of permanent magnet materials lifetime exceeds a 100-year period [2]. A lot of magnetic materials obtainable, varying from low energy and low-cost ferrites to a pricey and pumped-up RE materials. Magnetic materials are a crucial material to the society because of their ability to handle a group of tasks such as converting mechanical to electrical energy, transmit and distribute electric power, facilitate microwave communications, and provide the basis for data storage systems [2].

Naturally, electrical power will be used by a normal person multiple times. Either by switching on the plug for light or plugging any electrical device into a wall socket. Most of the electricity supplied by electrochemical devices like generators that use hydroelectric power plants or wind turbines. This electromagnetic energy conversion has a benefit relying on the use of an electromechanical device which does not need an external electrical source to generate electrical power. An example of this device is the current (AC) generator [3]. A coil inside the generator is being rotated by rotational mechanical energy which then exposes that coil to change in the magnetic field. Production of alternating current voltage is being induced because of those changes.

AC or direct-current (DC) electrical can be generated by using an electromagnetic energy source. In order to change the alternating current which coming out from power generator into one direction flowing current, or direct current, most DC motors and generators are using a parameter labeled commutator. This project is observing and analysing major nonlinear effects which is more about saturation, eddy currents, and Hysteresis. Due to the importance of this magnetic energy in the current system, observing the losses provide an advantage that can benefit the improvement of magnetic energy conversion production.

The experiment initially focusing on modelling out the magnetic losses in the periodic domain. Fourier method is the main method to identify the losses while applying some Fourier calculation inside a software. MATLAB is the essential software to test out this experiment since it completely satisfies the needs of the project. Once the losses have been identified and the behaviour is understandable, the result can be contributed to improving the efficiency of the magnetic energy conversion in many applications.

Naturally, in this paper, nonlinear parameters will be calculated in a much simpler way. From the result that obtained, the Gibbs effect will be present which is an unwanted natural phenomenon. Certainly, through this experiment, the Gibbs effect in Fourier methods will be reduced to achieve the perfect results.

Apart from it, this experiment is the best way to analyse the losses in nonlinear materials. It will give many students a bigger picture or overview regarding the nonlinear effects on each material. Hence, the behaviour of the losses can be observed and the ideas to resolve it will be generated. In order to look at the eddy current loss, hysteresis loss, and Gibbs effect, the device needs to be run hard enough since it can produce a higher voltage and current which then producing a demanded result.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [4].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [4].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [3].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [3]. Chen and Pillay in [4] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [5] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [5] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [6] which represents eddy current losses in soft magnetic materials.

Bertotti in [7] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E's aluminium.png|frame|center|E's Aluminium design]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure 17 and 18 shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

=== Design Iron Core ===

For the next design, the air core choke was replaced with an iron core choke to perform the same method of measurements and analysis that was done for the air-core choke. None of the circuit components were replaced to ensure the exact parameters that will be included in the measurements of the iron core choke. The iron core choke was obtained from the previous research project group.

[[File: Bottom view iron core.png|frame|center|Bottom view of the iron core choke]]
[[File: Side view of iron core.png|frame|center|side view of the iron core choke]]
[[File:Iron core model.png|frame|center|iron core model]]

== Results ==

=== Choke Air-core ===
[[File:Parameters air choke.png|frame|center|Waveform for air core parameter]]

Those waveforms were the result after the bug found during the measurement has been fixed.

=== BH curve air core ===

[[File:BH curve.png|frame|center|B-H curve waveform]]

The number of turns from the coil, the type of the material, and also the flow of the current along the coil affected the magnetic strength of the electromagnet. The B-H curve is the curve result on the flux density, B against the strength of the magnetic field, H. The ratio of flux density to field strength for ferromagnetic materials is not constant but contrasts with flux density. Since the result was from air core, this ratio was regarded as a constant, and this constant is known as free space permeability.

=== T-test ===

[[File:Inductor.png|frame|center|t-test sample for inductor]]
[[File:T-test graph.png|frame|center|t-distribution graph one tail]]

The result for t critical one tail analysis is stated in the figure above. 1.83311 is the t critical one tail value analysis which means that it is higher than the alpha value, 0.05. The value for the t critical one tail was 1.833 which cuts-off the alpha value at 0.05. The shape of the graph was affected by the value of degrees of freedom. The larger the degrees of freedom, the smaller the tails distribution area. Since the t critical one tail value is larger than the alpha value, thus the null hypothesis is accepted which there was no difference between both data.

=== Iron-Core ===

[[File:50V iron core.png|frame|center|Error voltage waveform on 50V]]

These waveforms were the reaction between the component inside the choke and the type of core material being used. These waveform results were affected by the value of the running voltage.

=== Aluminium-core Simulation ===

[[File:Flux density.png|frame|center|flux density aluminium core]]
[[File:Magnetising core.png|thumb|Magnetising force of the aluminium core]]

Both figures showed an identical waveform in which a sudden spike occurred at the 20mm length. This is due to the result that has been exceeding the length of the core at 20mm. when the waveform runs above the length of the core, a sudden spike on the flux density will be formed.

== Conclusion ==

For the conclusion. This thesis focuses on the experiment that is being conducted throughout the period of this research project and the findings that were obtained with it. Studying the nonlinearities element of an inductor choke with a different type of material promotes the urge to obtain a better understanding of the properties of the magnetization and the electrical parameters that were being presented in the measurement, calculations, and the waveforms that were plotted.

All the calibration process on the tools and the main components for the research project is completed and the offsets of the that occurred have been obtained and taken into account in the calculations. The hypothesis testing that was conducted strengthens the level of comparison in two different methods of measuring the parameters in which the MATLAB calculations and the LUTRON LCR meter have been accepted as the there differences between the results are not significant and with the acceptance range.

The usage of Picoscope and MATLAB in the research project has been considered a successful approach as it provides required results in the measurement of the air core inductor choke and the iron core inductor choke.
The magnetic properties of the air core inductor choke were obtained by creating the magnetisation curve which proves to be linear as the air core has no nonlinearities magnetic properties on it.

he simulation task that replaced the final measurement of the aluminium due to the unavoidable circumstances has been completed and analysed using the Ansys Maxwell software.

== References ==
[1] W. Matizamhuka, “The impact of magnetic materials in renewable energy-related technologies in the 21st century industrial revolution: The case of South Africa,” Adv. Mater. Sci. Eng., vol. 2018, 2018.

[2] W. Yang, L. Guo, Z. Guo, G. Dong, Y. Sui, and Z. Chen, “Improvement of the Magnetic Properties of Nanocrystalline Nd12.3(FeZrNbCu)81.7B6.0 Alloys with Dy Substitutions,” J. Nanomater., vol. 2015, 2015.

[3] Sandoval, David. (2019, November 1). What are the Advantages and Disadvantages of Electromagnetic Energy Power Sources? sciencing.com. Retrieved from https://sciencing.com/advantages-electromagnetic-energy-power-sources-6779004.html

[4] C. Kittel, Introduction to solid state physics, 5th ed. New York: Wiley, 1976.

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T17:17:44Z

A1722328: /* Ferromagnetism */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

Over the years, the development of technology focuses already transposes to renewables as a recent energy source limit. Majority performances of the device will be included magnetic materials to increase the efficiency of devices. Few examples of its application are transportation, electric generator, air conditioning, and telecommunications [1]. The historical development of permanent magnet materials lifetime exceeds a 100-year period [2]. A lot of magnetic materials obtainable, varying from low energy and low-cost ferrites to a pricey and pumped-up RE materials. Magnetic materials are a crucial material to the society because of their ability to handle a group of tasks such as converting mechanical to electrical energy, transmit and distribute electric power, facilitate microwave communications, and provide the basis for data storage systems [2].

Naturally, electrical power will be used by a normal person multiple times. Either by switching on the plug for light or plugging any electrical device into a wall socket. Most of the electricity supplied by electrochemical devices like generators that use hydroelectric power plants or wind turbines. This electromagnetic energy conversion has a benefit relying on the use of an electromechanical device which does not need an external electrical source to generate electrical power. An example of this device is the current (AC) generator [3]. A coil inside the generator is being rotated by rotational mechanical energy which then exposes that coil to change in the magnetic field. Production of alternating current voltage is being induced because of those changes.

AC or direct-current (DC) electrical can be generated by using an electromagnetic energy source. In order to change the alternating current which coming out from power generator into one direction flowing current, or direct current, most DC motors and generators are using a parameter labeled commutator. This project is observing and analysing major nonlinear effects which is more about saturation, eddy currents, and Hysteresis. Due to the importance of this magnetic energy in the current system, observing the losses provide an advantage that can benefit the improvement of magnetic energy conversion production.

The experiment initially focusing on modelling out the magnetic losses in the periodic domain. Fourier method is the main method to identify the losses while applying some Fourier calculation inside a software. MATLAB is the essential software to test out this experiment since it completely satisfies the needs of the project. Once the losses have been identified and the behaviour is understandable, the result can be contributed to improving the efficiency of the magnetic energy conversion in many applications.

Naturally, in this paper, nonlinear parameters will be calculated in a much simpler way. From the result that obtained, the Gibbs effect will be present which is an unwanted natural phenomenon. Certainly, through this experiment, the Gibbs effect in Fourier methods will be reduced to achieve the perfect results.

Apart from it, this experiment is the best way to analyse the losses in nonlinear materials. It will give many students a bigger picture or overview regarding the nonlinear effects on each material. Hence, the behaviour of the losses can be observed and the ideas to resolve it will be generated. In order to look at the eddy current loss, hysteresis loss, and Gibbs effect, the device needs to be run hard enough since it can produce a higher voltage and current which then producing a demanded result.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [4].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [4].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [3].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [3]. Chen and Pillay in [4] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [5] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [5] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [6] which represents eddy current losses in soft magnetic materials.

Bertotti in [7] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E's aluminium.png|frame|center|E's Aluminium design]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure 17 and 18 shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

=== Design Iron Core ===

For the next design, the air core choke was replaced with an iron core choke to perform the same method of measurements and analysis that was done for the air-core choke. None of the circuit components were replaced to ensure the exact parameters that will be included in the measurements of the iron core choke. The iron core choke was obtained from the previous research project group.

[[File: Bottom view iron core.png|frame|center|Bottom view of the iron core choke]]
[[File: Side view of iron core.png|frame|center|side view of the iron core choke]]
[[File:Iron core model.png|frame|center|iron core model]]

== Results ==

=== Choke Air-core ===
[[File:Parameters air choke.png|frame|center|Waveform for air core parameter]]

Those waveforms were the result after the bug found during the measurement has been fixed.

=== BH curve air core ===

[[File:BH curve.png|frame|center|B-H curve waveform]]

The number of turns from the coil, the type of the material, and also the flow of the current along the coil affected the magnetic strength of the electromagnet. The B-H curve is the curve result on the flux density, B against the strength of the magnetic field, H. The ratio of flux density to field strength for ferromagnetic materials is not constant but contrasts with flux density. Since the result was from air core, this ratio was regarded as a constant, and this constant is known as free space permeability.

=== T-test ===

[[File:Inductor.png|frame|center|t-test sample for inductor]]
[[File:T-test graph.png|frame|center|t-distribution graph one tail]]

The result for t critical one tail analysis is stated in the figure above. 1.83311 is the t critical one tail value analysis which means that it is higher than the alpha value, 0.05. The value for the t critical one tail was 1.833 which cuts-off the alpha value at 0.05. The shape of the graph was affected by the value of degrees of freedom. The larger the degrees of freedom, the smaller the tails distribution area. Since the t critical one tail value is larger than the alpha value, thus the null hypothesis is accepted which there was no difference between both data.

=== Iron-Core ===

[[File:50V iron core.png|frame|center|Error voltage waveform on 50V]]

These waveforms were the reaction between the component inside the choke and the type of core material being used. These waveform results were affected by the value of the running voltage.

=== Aluminium-core Simulation ===

[[File:Flux density.png|frame|center|flux density aluminium core]]
[[File:Magnetising core.png|thumb|Magnetising force of the aluminium core]]

Both figures showed an identical waveform in which a sudden spike occurred at the 20mm length. This is due to the result that has been exceeding the length of the core at 20mm. when the waveform runs above the length of the core, a sudden spike on the flux density will be formed.

== Conclusion ==

For the conclusion. This thesis focuses on the experiment that is being conducted throughout the period of this research project and the findings that were obtained with it. Studying the nonlinearities element of an inductor choke with a different type of material promotes the urge to obtain a better understanding of the properties of the magnetization and the electrical parameters that were being presented in the measurement, calculations, and the waveforms that were plotted.

All the calibration process on the tools and the main components for the research project is completed and the offsets of the that occurred have been obtained and taken into account in the calculations. The hypothesis testing that was conducted strengthens the level of comparison in two different methods of measuring the parameters in which the MATLAB calculations and the LUTRON LCR meter have been accepted as the there differences between the results are not significant and with the acceptance range.

The usage of Picoscope and MATLAB in the research project has been considered a successful approach as it provides required results in the measurement of the air core inductor choke and the iron core inductor choke.
The magnetic properties of the air core inductor choke were obtained by creating the magnetisation curve which proves to be linear as the air core has no nonlinearities magnetic properties on it.

he simulation task that replaced the final measurement of the aluminium due to the unavoidable circumstances has been completed and analysed using the Ansys Maxwell software.

== References ==
[1] W. Matizamhuka, “The impact of magnetic materials in renewable energy-related technologies in the 21st century industrial revolution: The case of South Africa,” Adv. Mater. Sci. Eng., vol. 2018, 2018.

[2] W. Yang, L. Guo, Z. Guo, G. Dong, Y. Sui, and Z. Chen, “Improvement of the Magnetic Properties of Nanocrystalline Nd12.3(FeZrNbCu)81.7B6.0 Alloys with Dy Substitutions,” J. Nanomater., vol. 2015, 2015.

[3] Sandoval, David. (2019, November 1). What are the Advantages and Disadvantages of Electromagnetic Energy Power Sources? sciencing.com. Retrieved from https://sciencing.com/advantages-electromagnetic-energy-power-sources-6779004.html

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T17:14:15Z

A1722328: /* References */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

Over the years, the development of technology focuses already transposes to renewables as a recent energy source limit. Majority performances of the device will be included magnetic materials to increase the efficiency of devices. Few examples of its application are transportation, electric generator, air conditioning, and telecommunications [1]. The historical development of permanent magnet materials lifetime exceeds a 100-year period [2]. A lot of magnetic materials obtainable, varying from low energy and low-cost ferrites to a pricey and pumped-up RE materials. Magnetic materials are a crucial material to the society because of their ability to handle a group of tasks such as converting mechanical to electrical energy, transmit and distribute electric power, facilitate microwave communications, and provide the basis for data storage systems [2].

Naturally, electrical power will be used by a normal person multiple times. Either by switching on the plug for light or plugging any electrical device into a wall socket. Most of the electricity supplied by electrochemical devices like generators that use hydroelectric power plants or wind turbines. This electromagnetic energy conversion has a benefit relying on the use of an electromechanical device which does not need an external electrical source to generate electrical power. An example of this device is the current (AC) generator [3]. A coil inside the generator is being rotated by rotational mechanical energy which then exposes that coil to change in the magnetic field. Production of alternating current voltage is being induced because of those changes.

AC or direct-current (DC) electrical can be generated by using an electromagnetic energy source. In order to change the alternating current which coming out from power generator into one direction flowing current, or direct current, most DC motors and generators are using a parameter labeled commutator. This project is observing and analysing major nonlinear effects which is more about saturation, eddy currents, and Hysteresis. Due to the importance of this magnetic energy in the current system, observing the losses provide an advantage that can benefit the improvement of magnetic energy conversion production.

The experiment initially focusing on modelling out the magnetic losses in the periodic domain. Fourier method is the main method to identify the losses while applying some Fourier calculation inside a software. MATLAB is the essential software to test out this experiment since it completely satisfies the needs of the project. Once the losses have been identified and the behaviour is understandable, the result can be contributed to improving the efficiency of the magnetic energy conversion in many applications.

Naturally, in this paper, nonlinear parameters will be calculated in a much simpler way. From the result that obtained, the Gibbs effect will be present which is an unwanted natural phenomenon. Certainly, through this experiment, the Gibbs effect in Fourier methods will be reduced to achieve the perfect results.

Apart from it, this experiment is the best way to analyse the losses in nonlinear materials. It will give many students a bigger picture or overview regarding the nonlinear effects on each material. Hence, the behaviour of the losses can be observed and the ideas to resolve it will be generated. In order to look at the eddy current loss, hysteresis loss, and Gibbs effect, the device needs to be run hard enough since it can produce a higher voltage and current which then producing a demanded result.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [2].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [2].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [3].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [3]. Chen and Pillay in [4] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [5] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [5] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [6] which represents eddy current losses in soft magnetic materials.

Bertotti in [7] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E's aluminium.png|frame|center|E's Aluminium design]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure 17 and 18 shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

=== Design Iron Core ===

For the next design, the air core choke was replaced with an iron core choke to perform the same method of measurements and analysis that was done for the air-core choke. None of the circuit components were replaced to ensure the exact parameters that will be included in the measurements of the iron core choke. The iron core choke was obtained from the previous research project group.

[[File: Bottom view iron core.png|frame|center|Bottom view of the iron core choke]]
[[File: Side view of iron core.png|frame|center|side view of the iron core choke]]
[[File:Iron core model.png|frame|center|iron core model]]

== Results ==

=== Choke Air-core ===
[[File:Parameters air choke.png|frame|center|Waveform for air core parameter]]

Those waveforms were the result after the bug found during the measurement has been fixed.

=== BH curve air core ===

[[File:BH curve.png|frame|center|B-H curve waveform]]

The number of turns from the coil, the type of the material, and also the flow of the current along the coil affected the magnetic strength of the electromagnet. The B-H curve is the curve result on the flux density, B against the strength of the magnetic field, H. The ratio of flux density to field strength for ferromagnetic materials is not constant but contrasts with flux density. Since the result was from air core, this ratio was regarded as a constant, and this constant is known as free space permeability.

=== T-test ===

[[File:Inductor.png|frame|center|t-test sample for inductor]]
[[File:T-test graph.png|frame|center|t-distribution graph one tail]]

The result for t critical one tail analysis is stated in the figure above. 1.83311 is the t critical one tail value analysis which means that it is higher than the alpha value, 0.05. The value for the t critical one tail was 1.833 which cuts-off the alpha value at 0.05. The shape of the graph was affected by the value of degrees of freedom. The larger the degrees of freedom, the smaller the tails distribution area. Since the t critical one tail value is larger than the alpha value, thus the null hypothesis is accepted which there was no difference between both data.

=== Iron-Core ===

[[File:50V iron core.png|frame|center|Error voltage waveform on 50V]]

These waveforms were the reaction between the component inside the choke and the type of core material being used. These waveform results were affected by the value of the running voltage.

=== Aluminium-core Simulation ===

[[File:Flux density.png|frame|center|flux density aluminium core]]
[[File:Magnetising core.png|thumb|Magnetising force of the aluminium core]]

Both figures showed an identical waveform in which a sudden spike occurred at the 20mm length. This is due to the result that has been exceeding the length of the core at 20mm. when the waveform runs above the length of the core, a sudden spike on the flux density will be formed.

== Conclusion ==

For the conclusion. This thesis focuses on the experiment that is being conducted throughout the period of this research project and the findings that were obtained with it. Studying the nonlinearities element of an inductor choke with a different type of material promotes the urge to obtain a better understanding of the properties of the magnetization and the electrical parameters that were being presented in the measurement, calculations, and the waveforms that were plotted.

All the calibration process on the tools and the main components for the research project is completed and the offsets of the that occurred have been obtained and taken into account in the calculations. The hypothesis testing that was conducted strengthens the level of comparison in two different methods of measuring the parameters in which the MATLAB calculations and the LUTRON LCR meter have been accepted as the there differences between the results are not significant and with the acceptance range.

The usage of Picoscope and MATLAB in the research project has been considered a successful approach as it provides required results in the measurement of the air core inductor choke and the iron core inductor choke.
The magnetic properties of the air core inductor choke were obtained by creating the magnetisation curve which proves to be linear as the air core has no nonlinearities magnetic properties on it.

he simulation task that replaced the final measurement of the aluminium due to the unavoidable circumstances has been completed and analysed using the Ansys Maxwell software.

== References ==
[1] W. Matizamhuka, “The impact of magnetic materials in renewable energy-related technologies in the 21st century industrial revolution: The case of South Africa,” Adv. Mater. Sci. Eng., vol. 2018, 2018.

[2] W. Yang, L. Guo, Z. Guo, G. Dong, Y. Sui, and Z. Chen, “Improvement of the Magnetic Properties of Nanocrystalline Nd12.3(FeZrNbCu)81.7B6.0 Alloys with Dy Substitutions,” J. Nanomater., vol. 2015, 2015.

[3] Sandoval, David. (2019, November 1). What are the Advantages and Disadvantages of Electromagnetic Energy Power Sources? sciencing.com. Retrieved from https://sciencing.com/advantages-electromagnetic-energy-power-sources-6779004.html

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T16:57:07Z

A1722328: /* Conclusion */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

Over the years, the development of technology focuses already transposes to renewables as a recent energy source limit. Majority performances of the device will be included magnetic materials to increase the efficiency of devices. Few examples of its application are transportation, electric generator, air conditioning, and telecommunications [1]. The historical development of permanent magnet materials lifetime exceeds a 100-year period [2]. A lot of magnetic materials obtainable, varying from low energy and low-cost ferrites to a pricey and pumped-up RE materials. Magnetic materials are a crucial material to the society because of their ability to handle a group of tasks such as converting mechanical to electrical energy, transmit and distribute electric power, facilitate microwave communications, and provide the basis for data storage systems [2].

Naturally, electrical power will be used by a normal person multiple times. Either by switching on the plug for light or plugging any electrical device into a wall socket. Most of the electricity supplied by electrochemical devices like generators that use hydroelectric power plants or wind turbines. This electromagnetic energy conversion has a benefit relying on the use of an electromechanical device which does not need an external electrical source to generate electrical power. An example of this device is the current (AC) generator [3]. A coil inside the generator is being rotated by rotational mechanical energy which then exposes that coil to change in the magnetic field. Production of alternating current voltage is being induced because of those changes.

AC or direct-current (DC) electrical can be generated by using an electromagnetic energy source. In order to change the alternating current which coming out from power generator into one direction flowing current, or direct current, most DC motors and generators are using a parameter labeled commutator. This project is observing and analysing major nonlinear effects which is more about saturation, eddy currents, and Hysteresis. Due to the importance of this magnetic energy in the current system, observing the losses provide an advantage that can benefit the improvement of magnetic energy conversion production.

The experiment initially focusing on modelling out the magnetic losses in the periodic domain. Fourier method is the main method to identify the losses while applying some Fourier calculation inside a software. MATLAB is the essential software to test out this experiment since it completely satisfies the needs of the project. Once the losses have been identified and the behaviour is understandable, the result can be contributed to improving the efficiency of the magnetic energy conversion in many applications.

Naturally, in this paper, nonlinear parameters will be calculated in a much simpler way. From the result that obtained, the Gibbs effect will be present which is an unwanted natural phenomenon. Certainly, through this experiment, the Gibbs effect in Fourier methods will be reduced to achieve the perfect results.

Apart from it, this experiment is the best way to analyse the losses in nonlinear materials. It will give many students a bigger picture or overview regarding the nonlinear effects on each material. Hence, the behaviour of the losses can be observed and the ideas to resolve it will be generated. In order to look at the eddy current loss, hysteresis loss, and Gibbs effect, the device needs to be run hard enough since it can produce a higher voltage and current which then producing a demanded result.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [2].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [2].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [3].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [3]. Chen and Pillay in [4] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [5] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [5] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [6] which represents eddy current losses in soft magnetic materials.

Bertotti in [7] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E's aluminium.png|frame|center|E's Aluminium design]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure 17 and 18 shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

=== Design Iron Core ===

For the next design, the air core choke was replaced with an iron core choke to perform the same method of measurements and analysis that was done for the air-core choke. None of the circuit components were replaced to ensure the exact parameters that will be included in the measurements of the iron core choke. The iron core choke was obtained from the previous research project group.

[[File: Bottom view iron core.png|frame|center|Bottom view of the iron core choke]]
[[File: Side view of iron core.png|frame|center|side view of the iron core choke]]
[[File:Iron core model.png|frame|center|iron core model]]

== Results ==

=== Choke Air-core ===
[[File:Parameters air choke.png|frame|center|Waveform for air core parameter]]

Those waveforms were the result after the bug found during the measurement has been fixed.

=== BH curve air core ===

[[File:BH curve.png|frame|center|B-H curve waveform]]

The number of turns from the coil, the type of the material, and also the flow of the current along the coil affected the magnetic strength of the electromagnet. The B-H curve is the curve result on the flux density, B against the strength of the magnetic field, H. The ratio of flux density to field strength for ferromagnetic materials is not constant but contrasts with flux density. Since the result was from air core, this ratio was regarded as a constant, and this constant is known as free space permeability.

=== T-test ===

[[File:Inductor.png|frame|center|t-test sample for inductor]]
[[File:T-test graph.png|frame|center|t-distribution graph one tail]]

The result for t critical one tail analysis is stated in the figure above. 1.83311 is the t critical one tail value analysis which means that it is higher than the alpha value, 0.05. The value for the t critical one tail was 1.833 which cuts-off the alpha value at 0.05. The shape of the graph was affected by the value of degrees of freedom. The larger the degrees of freedom, the smaller the tails distribution area. Since the t critical one tail value is larger than the alpha value, thus the null hypothesis is accepted which there was no difference between both data.

=== Iron-Core ===

[[File:50V iron core.png|frame|center|Error voltage waveform on 50V]]

These waveforms were the reaction between the component inside the choke and the type of core material being used. These waveform results were affected by the value of the running voltage.

=== Aluminium-core Simulation ===

[[File:Flux density.png|frame|center|flux density aluminium core]]
[[File:Magnetising core.png|thumb|Magnetising force of the aluminium core]]

Both figures showed an identical waveform in which a sudden spike occurred at the 20mm length. This is due to the result that has been exceeding the length of the core at 20mm. when the waveform runs above the length of the core, a sudden spike on the flux density will be formed.

== Conclusion ==

For the conclusion. This thesis focuses on the experiment that is being conducted throughout the period of this research project and the findings that were obtained with it. Studying the nonlinearities element of an inductor choke with a different type of material promotes the urge to obtain a better understanding of the properties of the magnetization and the electrical parameters that were being presented in the measurement, calculations, and the waveforms that were plotted.

All the calibration process on the tools and the main components for the research project is completed and the offsets of the that occurred have been obtained and taken into account in the calculations. The hypothesis testing that was conducted strengthens the level of comparison in two different methods of measuring the parameters in which the MATLAB calculations and the LUTRON LCR meter have been accepted as the there differences between the results are not significant and with the acceptance range.

The usage of Picoscope and MATLAB in the research project has been considered a successful approach as it provides required results in the measurement of the air core inductor choke and the iron core inductor choke.
The magnetic properties of the air core inductor choke were obtained by creating the magnetisation curve which proves to be linear as the air core has no nonlinearities magnetic properties on it.

he simulation task that replaced the final measurement of the aluminium due to the unavoidable circumstances has been completed and analysed using the Ansys Maxwell software.

== References ==
[1] https://engineering.mit.edu/engage/ask-an-engineer/why-cant-magnetism-be-used-as-a-source-of-energy/

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T16:52:27Z

A1722328: /* Results */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

Over the years, the development of technology focuses already transposes to renewables as a recent energy source limit. Majority performances of the device will be included magnetic materials to increase the efficiency of devices. Few examples of its application are transportation, electric generator, air conditioning, and telecommunications [1]. The historical development of permanent magnet materials lifetime exceeds a 100-year period [2]. A lot of magnetic materials obtainable, varying from low energy and low-cost ferrites to a pricey and pumped-up RE materials. Magnetic materials are a crucial material to the society because of their ability to handle a group of tasks such as converting mechanical to electrical energy, transmit and distribute electric power, facilitate microwave communications, and provide the basis for data storage systems [2].

Naturally, electrical power will be used by a normal person multiple times. Either by switching on the plug for light or plugging any electrical device into a wall socket. Most of the electricity supplied by electrochemical devices like generators that use hydroelectric power plants or wind turbines. This electromagnetic energy conversion has a benefit relying on the use of an electromechanical device which does not need an external electrical source to generate electrical power. An example of this device is the current (AC) generator [3]. A coil inside the generator is being rotated by rotational mechanical energy which then exposes that coil to change in the magnetic field. Production of alternating current voltage is being induced because of those changes.

AC or direct-current (DC) electrical can be generated by using an electromagnetic energy source. In order to change the alternating current which coming out from power generator into one direction flowing current, or direct current, most DC motors and generators are using a parameter labeled commutator. This project is observing and analysing major nonlinear effects which is more about saturation, eddy currents, and Hysteresis. Due to the importance of this magnetic energy in the current system, observing the losses provide an advantage that can benefit the improvement of magnetic energy conversion production.

The experiment initially focusing on modelling out the magnetic losses in the periodic domain. Fourier method is the main method to identify the losses while applying some Fourier calculation inside a software. MATLAB is the essential software to test out this experiment since it completely satisfies the needs of the project. Once the losses have been identified and the behaviour is understandable, the result can be contributed to improving the efficiency of the magnetic energy conversion in many applications.

Naturally, in this paper, nonlinear parameters will be calculated in a much simpler way. From the result that obtained, the Gibbs effect will be present which is an unwanted natural phenomenon. Certainly, through this experiment, the Gibbs effect in Fourier methods will be reduced to achieve the perfect results.

Apart from it, this experiment is the best way to analyse the losses in nonlinear materials. It will give many students a bigger picture or overview regarding the nonlinear effects on each material. Hence, the behaviour of the losses can be observed and the ideas to resolve it will be generated. In order to look at the eddy current loss, hysteresis loss, and Gibbs effect, the device needs to be run hard enough since it can produce a higher voltage and current which then producing a demanded result.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [2].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [2].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [3].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [3]. Chen and Pillay in [4] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [5] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [5] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [6] which represents eddy current losses in soft magnetic materials.

Bertotti in [7] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E's aluminium.png|frame|center|E's Aluminium design]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure 17 and 18 shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

=== Design Iron Core ===

For the next design, the air core choke was replaced with an iron core choke to perform the same method of measurements and analysis that was done for the air-core choke. None of the circuit components were replaced to ensure the exact parameters that will be included in the measurements of the iron core choke. The iron core choke was obtained from the previous research project group.

[[File: Bottom view iron core.png|frame|center|Bottom view of the iron core choke]]
[[File: Side view of iron core.png|frame|center|side view of the iron core choke]]
[[File:Iron core model.png|frame|center|iron core model]]

== Results ==

=== Choke Air-core ===
[[File:Parameters air choke.png|frame|center|Waveform for air core parameter]]

Those waveforms were the result after the bug found during the measurement has been fixed.

=== BH curve air core ===

[[File:BH curve.png|frame|center|B-H curve waveform]]

The number of turns from the coil, the type of the material, and also the flow of the current along the coil affected the magnetic strength of the electromagnet. The B-H curve is the curve result on the flux density, B against the strength of the magnetic field, H. The ratio of flux density to field strength for ferromagnetic materials is not constant but contrasts with flux density. Since the result was from air core, this ratio was regarded as a constant, and this constant is known as free space permeability.

=== T-test ===

[[File:Inductor.png|frame|center|t-test sample for inductor]]
[[File:T-test graph.png|frame|center|t-distribution graph one tail]]

The result for t critical one tail analysis is stated in the figure above. 1.83311 is the t critical one tail value analysis which means that it is higher than the alpha value, 0.05. The value for the t critical one tail was 1.833 which cuts-off the alpha value at 0.05. The shape of the graph was affected by the value of degrees of freedom. The larger the degrees of freedom, the smaller the tails distribution area. Since the t critical one tail value is larger than the alpha value, thus the null hypothesis is accepted which there was no difference between both data.

=== Iron-Core ===

[[File:50V iron core.png|frame|center|Error voltage waveform on 50V]]

These waveforms were the reaction between the component inside the choke and the type of core material being used. These waveform results were affected by the value of the running voltage.

=== Aluminium-core Simulation ===

[[File:Flux density.png|frame|center|flux density aluminium core]]
[[File:Magnetising core.png|thumb|Magnetising force of the aluminium core]]

Both figures showed an identical waveform in which a sudden spike occurred at the 20mm length. This is due to the result that has been exceeding the length of the core at 20mm. when the waveform runs above the length of the core, a sudden spike on the flux density will be formed.

== Conclusion ==

== References ==
[1] https://engineering.mit.edu/engage/ask-an-engineer/why-cant-magnetism-be-used-as-a-source-of-energy/

File:Magnetising core.png

2020-06-06T16:50:55Z

A1722328:

Magnetising force of the aluminium core

File:Flux density.png

2020-06-06T16:49:54Z

A1722328:

flux density aluminium cora

File:50V iron core.png

2020-06-06T16:46:00Z

A1722328:

error voltage waveform on 50V

File:T-test graph.png

2020-06-06T16:42:22Z

A1722328:

t-distribution graph one tail

File:Inductor.png

2020-06-06T16:39:10Z

A1722328:

t-test sample for inductor

File:BH curve.png

2020-06-06T16:37:04Z

A1722328:

BH curve waveform

File:Parameters air choke.png

2020-06-06T16:34:36Z

A1722328:

Waveform for air choke parameter

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T16:14:10Z

A1722328: /* Method */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

Over the years, the development of technology focuses already transposes to renewables as a recent energy source limit. Majority performances of the device will be included magnetic materials to increase the efficiency of devices. Few examples of its application are transportation, electric generator, air conditioning, and telecommunications [1]. The historical development of permanent magnet materials lifetime exceeds a 100-year period [2]. A lot of magnetic materials obtainable, varying from low energy and low-cost ferrites to a pricey and pumped-up RE materials. Magnetic materials are a crucial material to the society because of their ability to handle a group of tasks such as converting mechanical to electrical energy, transmit and distribute electric power, facilitate microwave communications, and provide the basis for data storage systems [2].

Naturally, electrical power will be used by a normal person multiple times. Either by switching on the plug for light or plugging any electrical device into a wall socket. Most of the electricity supplied by electrochemical devices like generators that use hydroelectric power plants or wind turbines. This electromagnetic energy conversion has a benefit relying on the use of an electromechanical device which does not need an external electrical source to generate electrical power. An example of this device is the current (AC) generator [3]. A coil inside the generator is being rotated by rotational mechanical energy which then exposes that coil to change in the magnetic field. Production of alternating current voltage is being induced because of those changes.

AC or direct-current (DC) electrical can be generated by using an electromagnetic energy source. In order to change the alternating current which coming out from power generator into one direction flowing current, or direct current, most DC motors and generators are using a parameter labeled commutator. This project is observing and analysing major nonlinear effects which is more about saturation, eddy currents, and Hysteresis. Due to the importance of this magnetic energy in the current system, observing the losses provide an advantage that can benefit the improvement of magnetic energy conversion production.

The experiment initially focusing on modelling out the magnetic losses in the periodic domain. Fourier method is the main method to identify the losses while applying some Fourier calculation inside a software. MATLAB is the essential software to test out this experiment since it completely satisfies the needs of the project. Once the losses have been identified and the behaviour is understandable, the result can be contributed to improving the efficiency of the magnetic energy conversion in many applications.

Naturally, in this paper, nonlinear parameters will be calculated in a much simpler way. From the result that obtained, the Gibbs effect will be present which is an unwanted natural phenomenon. Certainly, through this experiment, the Gibbs effect in Fourier methods will be reduced to achieve the perfect results.

Apart from it, this experiment is the best way to analyse the losses in nonlinear materials. It will give many students a bigger picture or overview regarding the nonlinear effects on each material. Hence, the behaviour of the losses can be observed and the ideas to resolve it will be generated. In order to look at the eddy current loss, hysteresis loss, and Gibbs effect, the device needs to be run hard enough since it can produce a higher voltage and current which then producing a demanded result.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [2].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [2].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [3].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [3]. Chen and Pillay in [4] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [5] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [5] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [6] which represents eddy current losses in soft magnetic materials.

Bertotti in [7] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E's aluminium.png|frame|center|E's Aluminium design]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure 17 and 18 shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

=== Design Iron Core ===

For the next design, the air core choke was replaced with an iron core choke to perform the same method of measurements and analysis that was done for the air-core choke. None of the circuit components were replaced to ensure the exact parameters that will be included in the measurements of the iron core choke. The iron core choke was obtained from the previous research project group.

[[File: Bottom view iron core.png|frame|center|Bottom view of the iron core choke]]
[[File: Side view of iron core.png|frame|center|side view of the iron core choke]]
[[File:Iron core model.png|frame|center|iron core model]]

== Results ==

== Conclusion ==

== References ==
[1] https://engineering.mit.edu/engage/ask-an-engineer/why-cant-magnetism-be-used-as-a-source-of-energy/

File:Iron core model.png

2020-06-06T16:13:50Z

A1722328:

Iron core model

File:Side view of iron core.png

2020-06-06T16:12:01Z

A1722328:

side view of the iron core choke

File:Bottom view iron core.png

2020-06-06T16:10:00Z

A1722328:

Bottom view of the iron core choke

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T16:07:11Z

A1722328: /* Design Aluminium Core */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

Over the years, the development of technology focuses already transposes to renewables as a recent energy source limit. Majority performances of the device will be included magnetic materials to increase the efficiency of devices. Few examples of its application are transportation, electric generator, air conditioning, and telecommunications [1]. The historical development of permanent magnet materials lifetime exceeds a 100-year period [2]. A lot of magnetic materials obtainable, varying from low energy and low-cost ferrites to a pricey and pumped-up RE materials. Magnetic materials are a crucial material to the society because of their ability to handle a group of tasks such as converting mechanical to electrical energy, transmit and distribute electric power, facilitate microwave communications, and provide the basis for data storage systems [2].

Naturally, electrical power will be used by a normal person multiple times. Either by switching on the plug for light or plugging any electrical device into a wall socket. Most of the electricity supplied by electrochemical devices like generators that use hydroelectric power plants or wind turbines. This electromagnetic energy conversion has a benefit relying on the use of an electromechanical device which does not need an external electrical source to generate electrical power. An example of this device is the current (AC) generator [3]. A coil inside the generator is being rotated by rotational mechanical energy which then exposes that coil to change in the magnetic field. Production of alternating current voltage is being induced because of those changes.

AC or direct-current (DC) electrical can be generated by using an electromagnetic energy source. In order to change the alternating current which coming out from power generator into one direction flowing current, or direct current, most DC motors and generators are using a parameter labeled commutator. This project is observing and analysing major nonlinear effects which is more about saturation, eddy currents, and Hysteresis. Due to the importance of this magnetic energy in the current system, observing the losses provide an advantage that can benefit the improvement of magnetic energy conversion production.

The experiment initially focusing on modelling out the magnetic losses in the periodic domain. Fourier method is the main method to identify the losses while applying some Fourier calculation inside a software. MATLAB is the essential software to test out this experiment since it completely satisfies the needs of the project. Once the losses have been identified and the behaviour is understandable, the result can be contributed to improving the efficiency of the magnetic energy conversion in many applications.

Naturally, in this paper, nonlinear parameters will be calculated in a much simpler way. From the result that obtained, the Gibbs effect will be present which is an unwanted natural phenomenon. Certainly, through this experiment, the Gibbs effect in Fourier methods will be reduced to achieve the perfect results.

Apart from it, this experiment is the best way to analyse the losses in nonlinear materials. It will give many students a bigger picture or overview regarding the nonlinear effects on each material. Hence, the behaviour of the losses can be observed and the ideas to resolve it will be generated. In order to look at the eddy current loss, hysteresis loss, and Gibbs effect, the device needs to be run hard enough since it can produce a higher voltage and current which then producing a demanded result.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [2].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [2].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [3].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [3]. Chen and Pillay in [4] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [5] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [5] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [6] which represents eddy current losses in soft magnetic materials.

Bertotti in [7] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E's aluminium.png|frame|center|E's Aluminium design]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure 17 and 18 shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

== Results ==

== Conclusion ==

== References ==
[1] https://engineering.mit.edu/engage/ask-an-engineer/why-cant-magnetism-be-used-as-a-source-of-energy/

File:E's aluminium.png

2020-06-06T16:06:42Z

A1722328:

E's Aluminium design

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T16:03:14Z

A1722328: /* Design Aluminium Core */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]

== Abstract ==

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==

Modelling of Magnetic Energy Conversion in Periodic Domain is the calculation of unwanted behaviour that does exist when the energy was being converted to magnetic energy. From this project name, the magnetic energy was being converted in a periodic domain because of most of the result that this project get was not sinusoidal. Thus, it needs to be calculated in a periodic domain in which this project will use a Complex Fourier Analysis (CFA) and Inverse Complex Fourier Analysis (ICFA) in Matlab software to calculate the value of all parameters in the project model circuit. This project wanted to study the behaviour of each power loss that can
exist during energy conversions like eddy current losses and hysteresis losses. The modelling will take place as the figure shown which the choke will be this project device under test.

=== Motivation ===

Over the years, the development of technology focuses already transposes to renewables as a recent energy source limit. Majority performances of the device will be included magnetic materials to increase the efficiency of devices. Few examples of its application are transportation, electric generator, air conditioning, and telecommunications [1]. The historical development of permanent magnet materials lifetime exceeds a 100-year period [2]. A lot of magnetic materials obtainable, varying from low energy and low-cost ferrites to a pricey and pumped-up RE materials. Magnetic materials are a crucial material to the society because of their ability to handle a group of tasks such as converting mechanical to electrical energy, transmit and distribute electric power, facilitate microwave communications, and provide the basis for data storage systems [2].

Naturally, electrical power will be used by a normal person multiple times. Either by switching on the plug for light or plugging any electrical device into a wall socket. Most of the electricity supplied by electrochemical devices like generators that use hydroelectric power plants or wind turbines. This electromagnetic energy conversion has a benefit relying on the use of an electromechanical device which does not need an external electrical source to generate electrical power. An example of this device is the current (AC) generator [3]. A coil inside the generator is being rotated by rotational mechanical energy which then exposes that coil to change in the magnetic field. Production of alternating current voltage is being induced because of those changes.

AC or direct-current (DC) electrical can be generated by using an electromagnetic energy source. In order to change the alternating current which coming out from power generator into one direction flowing current, or direct current, most DC motors and generators are using a parameter labeled commutator. This project is observing and analysing major nonlinear effects which is more about saturation, eddy currents, and Hysteresis. Due to the importance of this magnetic energy in the current system, observing the losses provide an advantage that can benefit the improvement of magnetic energy conversion production.

The experiment initially focusing on modelling out the magnetic losses in the periodic domain. Fourier method is the main method to identify the losses while applying some Fourier calculation inside a software. MATLAB is the essential software to test out this experiment since it completely satisfies the needs of the project. Once the losses have been identified and the behaviour is understandable, the result can be contributed to improving the efficiency of the magnetic energy conversion in many applications.

Naturally, in this paper, nonlinear parameters will be calculated in a much simpler way. From the result that obtained, the Gibbs effect will be present which is an unwanted natural phenomenon. Certainly, through this experiment, the Gibbs effect in Fourier methods will be reduced to achieve the perfect results.

Apart from it, this experiment is the best way to analyse the losses in nonlinear materials. It will give many students a bigger picture or overview regarding the nonlinear effects on each material. Hence, the behaviour of the losses can be observed and the ideas to resolve it will be generated. In order to look at the eddy current loss, hysteresis loss, and Gibbs effect, the device needs to be run hard enough since it can produce a higher voltage and current which then producing a demanded result.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===

While the main aim of this project is to model a magnetic energy conversion in the periodic domain, the definite objectives of this project are:

* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==

A magnetic device that is choke plays an important parameter that will be used in this experiment. This device helps with understanding nonlinear effects which will be testing by driving the device hard. It will be running with a high voltage up until its thermal limit. This choke consists of a series of inductors and resistors approximately at 2.28mH and 3.74 ohms, respectively. 240V transformer with 50Hz frequency is the main supply in this experiment. Some of the materials that will be used to be attached to the choke are iron and aluminium. However, before begins the experiment on iron and aluminium, the bare choke will be tested to get an air-core reading.

Data acquired through the experiment will be analyse in MATLAB software. Since this experiment handling thousands of data, it needs an efficient method to best examine them. Thus, Fourier Series is the method for modelling of the magnetic losses in a periodic domain. A code for the complex Fourier series is created and applied along with the obtained data code.

As soon as the data has been analysed, the result might produce quantization noise and propagation of error. Quantization noise is an unwanted signal that been bothering the ideal produced output. Propagation of error is the uncertainty in the result itself. It might come from random sources. Be it from the wire, the connection, or the technical devices from the experiment. These errors are unwanted errors that need to be removed and analysed. The solution for this issue is applying a statistical analysis that finding its mean value, variance, standard deviation, and many more.

The model will experiment with different types of core such as aluminium since aluminium produce high losses of eddy current which is our main objective of the experiment. The bare choke is being tested as it is linear and provides understandable behaviour. It is the base testing as a starting point to understand more on the model. Apart from aluminium, steel lamination will also be tested as it will produce all needed effects such as Gibbs effect, hysteresis loss, and eddy current loss.

=== Ferromagnetism ===

Understanding how Ferromagnetism works is key as it is the main mechanism that occurred throughout this project. In definition, Ferromagnetism is the magnetization processed that occurred to a ferromagnetic material such as iron in order to become a permanent magnet. This phenomenon can happen when a magnetic moment of the ferromagnet it means that the electron spins to be arranged in a regular manner [2].

The Curie temperature is defined by the temperature above the spontaneous magnetization that occurred vanished. When the temperature is below the Curie point, the electromagnetic moments of the ferromagnet lined up in a regular manner but it is possible that the magnetic moment is less than the saturation moment of the ferromagnet. Thus, an external magnetic field is required in order to saturate the material [2].

In relation to this research project, the operating condition of the ferromagnet tested involved a high voltage condition which will result in an increase in temperature to the magnetic device. It may affect the result gathered to a certain degree and can be analyzed further with a mathematical approach.

=== Losses in Ferromagnetic components ===

For ferromagnetic materials, the total iron losses can be both the hysteresis loss and the dynamic losses which include the eddy current loss and some excess losses. The hysteresis losses are most commonly related to the domain walls when the external magnetic field is applied to the ferromagnet [3].

[[File:Captured.png|frame|center|an example of the hysteresis loop and magnetisation curve]]

Eddy current loss is the losses that occurred when the domain walls of the ferromagnet have some current being induced on it. The thickness of the core materials plays a part in this loss and the thickness of the material sheet can also affect the direction of the induced current [3]. Chen and Pillay in [4] mention that the changing external magnetic has a huge impact on the magnitude of the less depending on its rate.

Chua and Stromsmoe in [5] have discovered a mathematical approach to model the hysteresis loss in which the mathematical model is defined in equation (1).

𝑑𝑦/𝑑𝑡=𝑔𝑜[𝑥(𝑡)−𝑓(𝑦(𝑡))] [5] (1)

The equation above related the variable of x(t) and y(t) of a hysteresis loop. g() and f() in the equation are said to be increasing monotonically and are differentiable on to other functions that consist of nonzero slopes in the real line as long as it satisfies the property of g(0) = f(0) = 0 [5].

The Chua model parameters have been successfully interpreted physically by using a barlike domain wall model experimented in [6] which represents eddy current losses in soft magnetic materials.

Bertotti in [7] proposed a concept that is originally a concept of an elemental operator with a graphical interpretation and biaxial anisotropy which is called the Preisach model.

The excess losses are considered as the additional eddy currents that are being generated by the displacement of the domain walls of the ferromagnetic materials. These excess losses are affected by the time variation of the magnetic induction period.h

== Method ==
=== Air-Core Design ===

[[File:Model.png|frame|center|Model Apparatus]]

The figure above shows a definite model to be used throughout this experiment. Transformer, linear choke which consist of both resistor and inductor, two parallel resistors are the main device involve in the model. The connection is well arranged with a labelled section. Aluminium and electrical steel lamination are not yet to be tested. The first experiment is focusing more on-base choke which is an air-core device. The behavior of air-core needs to be analysed. Since the voltage will be driven hard, the current probably increasing, hence thermocouple is being attached to the choke to supervise the temperature for not being too hot. Air-core testing is important as it is the base experiment to show the exact behavior of the core.

=== Design Aluminium Core ===

This project needs to use an aluminium core to identify the eddy current losses in the magnetic materials. In this process, the help of a technician is crucial since it involves a high-risk process that requires cutting and laminating the iron core. In order to do an aluminium choke, the E’s and I’s need to be done by using the aluminium material. The aluminium core designation was being done in the AutoCAD software in order to give precise detail about the design project.

[[File:E aluminium design.png|frame|center]]

[[File:I aluminium.png|frame|center|I's aluminium design]]

Figure 17 and 18 shows the design of E’s and I’s in the AutoCAD software. The diameter of the measurement was taken by measuring the previous E’s and I’s of iron material. The thickness of the E’s and I’s is 1 mm of each block. The amount of aluminium E’s and I’s were around 30 blocks each. The aluminium choke can be created by stacking the aluminium of E’s and I’s on top of each other until there was no gap to be fill. Then, the aluminium core needs to be laminated and varnished. This was done in order to prevent any air gaps and current from flowing in between each block.

== Results ==

== Conclusion ==

== References ==
[1] https://engineering.mit.edu/engage/ask-an-engineer/why-cant-magnetism-be-used-as-a-source-of-energy/

File:I aluminium.png

2020-06-06T16:01:56Z

A1722328:

I's aluminium design

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T15:19:43Z

A1722328: /* Designing Project */

File:E aluminium design.png

2020-06-06T15:19:28Z

A1722328:

E's aluminium Design

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T15:14:07Z

A1722328: /* Designing Project */

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T15:13:55Z

A1722328: /* Designing Project */

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T15:11:57Z

A1722328: /* Designing Project */

File:Model.png

2020-06-06T15:11:34Z

A1722328:

Model Apparatus

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T15:10:43Z

A1722328: /* Method */

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T14:33:26Z

A1722328: /* Losses in Ferromagnetic components */

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T14:20:13Z

A1722328: /* Losses in Ferromagnetic components */

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T14:19:37Z

A1722328: /* Losses in Ferromagnetic components */

File:Captured.png

2020-06-06T14:18:58Z

A1722328:

hysteresis loop and magnetisation curve

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T14:15:26Z

A1722328: /* Background */

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T13:43:18Z

A1722328: /* Objectives */

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T13:33:49Z

A1722328: /* Objective */

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T13:32:14Z

A1722328: /* Introduction */

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T12:32:56Z

A1722328:

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T12:30:46Z

A1722328:

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]
Abstract

Magnetic systems play a significant role in energy conversion as almost every type of energy conversion involves a magnetic device. For example, wind turbines and thermal energy use generators which is a magnetic device to produce electric energy by electromagnetic induction. A magnetic device such as generators, motors, and transformers have non-linear aspects that need to be considered. The non-linear aspects can be in a form of saturation, hysteresis, and eddy current.

Studying the effects of nonlinearities in an inductor choke circuit model will be the main motivation of this project. By conducting the experiment with the operating condition that can produce these nonlinear effects to be significant, detailed analysis will be performed to study the behaviour of the nonlinear effects. In order to get precise and accurate data from the experiments, more advanced tools need to be used such as PicoScope developed by Pico Technology.

Detailed analysis can be performed once all the data gathering process has been completed. By using a Fourier series method, the magnetic losses can be model out in a periodic domain which then can be studied further using statistical analysis.

== Introduction ==
Magnetic systems are widely used in energy conversion. In a magnetic system, we can obtain the nonlinear aspects which are hysteresis and eddy current loss.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===
* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==
=== Topic 1 ===

== Method ==

== Results ==

== Conclusion ==

== References ==
[1] https://engineering.mit.edu/engage/ask-an-engineer/why-cant-magnetism-be-used-as-a-source-of-energy/

Projects:2019s2-25102 Modelling of Magnetic Energy Conversion in the Periodic Domain

2020-06-06T11:57:05Z

A1722328: /* Objectives */

[[Category:Projects]]
[[Category:Final Year Projects]]
[[Category:2018s1|106]]
Abstract here
== Introduction ==
Magnetic systems are widely used in energy conversion. In a magnetic system, we can obtain the nonlinear aspects which are hysteresis and eddy current loss.

=== Project team ===
==== Project students ====
* Mohamed Amin Bin Abdul Rafid
* Nabil Munir Bin Ahmad
* Nur Akhira Binti Kamar Baharin

==== Supervisors ====
* Dr. Andrew Allison
* Prof. Derek Abbott

=== Objectives ===
* Study and understand the nonlinear effects in a magnetic devices.
* Modelling out the magnetic losses in the periodic domain (Fourier Method).
* Apply statistical analysis in measurement
* Simulation of magnetic properties.

== Background ==
=== Topic 1 ===

== Method ==

== Results ==

== Conclusion ==

== References ==
[1] https://engineering.mit.edu/engage/ask-an-engineer/why-cant-magnetism-be-used-as-a-source-of-energy/