Projects - User contributions [en]

Projects:2019s1-156 Ear-Plug Brain Wave Reader

2019-10-30T08:32:10Z

A1655751:

'''Motivation'''
The brain as the control center of advanced creature not only controls the biological's motor function, but also plays a decisive role in mood and personality. In additional, it could provide information about brain diseases but are also useful for assessing cognitive states and monitoring sleep.

In 1791, L. GalVani found that the current was generated when the muscles contracted, which provided a theoretical basis for the development of EEG. Besides, researchers have begun to realize that brain activity is also accompanied by the electrical signals. Since then, EEG technology has developed rapidly. After entering the 20th century, with the generation of transistors, the recording method for EEG has also evolved to magnify EEG through a transistor amplifier and record it with an oscilloscope. In recent years, with the development of EEG technology, it has begun to enter the ordinary family and is used as a medical device for home use. At the same time, some small-scale portable EEG acquisition systems have appeared in the domestic and international markets for home health monitoring and other fields.

'''Background'''
The aim of our project is to design EEG sensor that collect brain waves via earplug, in the future, can be integrated in earphone. The purpose of our project is to design a ear-plug electrodes to collect EEG signal, to design circuit board to realize the the layout of the system and drawing of the PCB board for signal processing, and design an application of Android system to display brainwaves.

'''Methodology'''
'''Electrodes'''
In order to collect the brain waves data through ear canals, we manufactured two earplugs with electrodes being carried on them. We found the 3D model of human outer and middle ear canal from the Internet, then we use the Autodesk Inventor Professional software to do a little bit of modifying to the 3D model to fit our ears’ conditions. The earplugs were made of silicone rubber, and they are both elastic and safe to touch the skin.
For the electrodes, as the earplugs are quite soft, we use conductive thread for electrodes instead of metallic electrodes due to its comfortability. The material of conductive thread was silver laced nylon, it was sewed on the head part of the earplugs and will contact the middle part of ear canal. The other side of conductive thread was connected to 1.2m copper wires separately. There are four sewed electrodes on each earplug and two earplugs worn by the user, so there were eight channels of input to the hardware system.

[[File:ADS1299.png|thumb]]

[[File:BLUETOOTH MODULE.png|thumb]]

[[File:POWER MODULE.png|thumb]]

[[File:CONNECTOR.png|thumb]]

[[File:ELECTRODE.png|thumb]]

'''ADS1299 MODULE'''
The ADS1299 is the high performance chip as control core to ensure the stability of the system and it integrates a programmable gain amplifier, internal reference source and on-chip clock.
ADS1299 data interaction with Bluetooth module: pin43 and pin34;
It has three power supplies, two analog power supplies (AVDD and AVSS) and one digital power supply Source (AVDD). Each power supply of the chip is connected to the ground through 10 μ F and 0.1 μ f to filter the power supply

'''Bluetooth module'''
Data exchange between the Bluetooth module and the ADS1299:
Bluetooth power is supplied using VDD3.3V; Bluetooth 1-pin is used as the data exchange output, and 2-pin is used as the data exchange input;
The 31-pin is connected to the LED light to indicate the working state of the module. The module flashes after power-on, and the blinking intervals of different states are different

'''Power module'''
U0: Power supply for USB, 5V voltage source, is the source of the entire power supply;
U2: TPS60403, -5V voltage, as an input to AVSS;
U3: TPS73225, output AVDD, providing analog power for ADS1299;
U4: TPS72325, output AVSS, providing analog power for ADS1299;
U5: MIC5501-3.3YMT, output 3.3V, providing digital power for ADS1299 and Bluetooth;
R0: single point grounding of analog ground and digital ground
C0: Filter between AVDD and AVSS

'''Application'''
We have made an Android app for our users to monitor their brainwaves through their Android devices live. The app was written in Java, which is a popular language in writing Android apps. This app requires the use of Bluetooth of Android devices and it receives data from the hardware system after getting access to Bluetooth. The app then separates the amplitude information from the data and shows it as a dynamic plot on the screen. Therefore, users can see their brain wave plot from the app.

'''Further Work'''
There are still functions which could be added to our device. Firstly is the deep learning systems, which makes the computer study the brain waves data of the user and learn the difference among various frequencies of brain waves from human activities. Therefore, the app can identify the condition of the user’s brain. Alerting programs can also be added to the app, alerting messages can be announced while the system detects abnormal brain waves data. This may help in family members monitoring the conditions of elder people.

Projects:2019s1-156 Ear-Plug Brain Wave Reader

2019-10-30T08:31:06Z

A1655751:

File:ELECTRODE.png

2019-10-30T08:29:11Z

A1655751:

ELECTRODE 3D PRINTER MODULE

File:CONNECTOR.png

2019-10-30T08:26:39Z

A1655751:

THE SCHEMATIC OF CONNECTOR MODULE

File:POWER MODULE.png

2019-10-30T08:26:00Z

A1655751:

THE SCHEMATIC OF POWER MODULE

File:BLUETOOTH MODULE.png

2019-10-30T08:25:23Z

A1655751:

THE SCHEMATIC OF BLUETOOTH MODULE

File:ADS1299.png

2019-10-30T08:24:31Z

A1655751:

THE SCHEMATIC OF ADS1299

Projects:2019s1-156 Ear-Plug Brain Wave Reader

2019-10-30T04:35:13Z

A1655751: Created page with "'''Motivation''' The brain as the control center of advanced creature not only controls the biological's motor function, but also plays a decisive role in mood and personality..."

Projects:2017s2-291 Measurement of Transformer Parameters

2018-06-05T05:23:52Z

A1655751: /* Method */

=Members=
Yiwei Sun

Zhouyajie xu

Zhi Li

supervisor: Andrew Allison

=Introduction=
A transformer is an electrical device based on Faradays’ law of electromagnetic induction to change alternating voltage, such as increasing or reducing voltage. We are interested in transformer in this project because it is widely be used in power industrial and essential for power transmission over long distance in power grid. Knowing parameters inside transformer will help us understanding the structure of transformer more clearly, and the method used to predict parameters inside transformer is useful for further study measurement which non-linear input and output.
This project also improve our ability of dealing with model, how to fit expected model outcomes with reality outcomes and how to analysis and minimize errors between them.

The aim of this project is mapping the transformer device in figure1.2 with the model of equivalence circuit to get 7 parameters value inside transformer model as “accurate” as possible.
This project is trying to using figure2 to match with figure 1. In another word, comparing our reality measurement of transformer with the theoretical model and analysis error between them.
To summarize the aim of this project:

• Analysis the model in figure 1.1, doing the rough test to get a rough 6 parameters.

• Substitute these rough parameters into transformer model for open circuit, short circuit and cross circuit of transformer to get these input impedance which record as Zin_model

• Measuring the open, short and cross circuit use transformer in figure 1.2 to get input impedance of measure Zin which record as Zin_measure.

• Error analysis between Zin_model and Zin_measure, then optimize error and get final 7 parameters result.

[[File:wiki00.png]]

=Method=
In order to get value of R and X, we measure input voltage and current from port A and port B as one terminal which shows in figure 3.1. From ohms law, the input impedance isZin =Vin/Iin. Splitting the real part and imaginary part of Zin to get R and X value respectively. R=real(Zin), X=imaginary(Zin).

The one-port model which also known as choke is consist of a resistor and inductor.

[[File:Choke one port.png|400px]]

Two-port model is more complicate than one port model, but the method we used to get parameters is similar as one-port model. Doing open circuit and short circuit for primary side (240V) of transformer and secondary side (24V) and two cross connection tests. Each case of these tests can be regard as one-port test and collect Vin and Iin for each test to calculate Zin based on ohms law.
For sub-section Zin model, as we have 6 Zin for open circuit connection, short circuit connection and cross connection, we derive formula for these six Zin based on R1, X1, R2, X2, Rc and Xm then substitute rough parameters we get from section 4 into our derived formula.

[[File:Two_port_test_box.png|400px]]

For measured Zin, the setting up of equipment which including power analyser, oscilloscope for measurement and using varic for power supply. In order to keep current consistency, the Zin for cross connection should be discharged, thus we have 4 Zin to collect. We regarding 4 Zin which has same current as a group, we measure 11 times to get 11 groups of Zin. Actually we have done a lot measurements for these 6 Zin, but only these 11 groups of Zin has the consistency current and useful, I will demonstrate specifically in this sub-section of measured Zin.
The sub-section Matlab method is mainly about the method and approach for data analysis.

[[File:flow of data.png|400px]]

=Data analyzing=
To obtain the overall variation of the impedance and to avoid damage to any of the devices, the input voltage range for all AC tests was as large as it could be possible. The Matlab file saturation.m programming for accumulate impedance and plot the curve. From these two curves, it is clear that the impedance of first circuit is varying with the condition of operation with a trend similar to that of the PMG choke. The resistance and reactance didn’t reach the peak value at the same time as well. However, there is no air gap in the two-port transformer and that is the reason why the impedance reached the peak value and decreased sharply instead of staying at the peak value for a wider voltage range. The peak of the curve is where the transformer reaches saturation.
[[File:curve 1.png|400px|border|left|middle|emf vs R curve of two-port #1 test, for 50-240V ]]

[[File:curve 2.png|400px|border|center|middle|emf vs L curve of two-port #1 test, for 50-240V ]]

=Findings=
After data analysis, it was found that the average reactance numerical values of the linear parameters in a T model equivalent circuit strongly depend on the operating condition of the transformer.
In addition, the following findings were made in this project:

• The impedance of a PMG choke does not stay constant after reaching the maximum value during varying operating conditions.

• The equivalent circuit of a PMG choke is not only a resistor and an inductor in series. Or there are huge error occurred during measurement.

• Resistance and reactance do not reach the peak value in the same operating condition.

• Impedance of a transformer remains constant if the current through its windings is maintained at the same value.

• Resistance slightly depends on the operating condition after saturation.

=Conclusion=
This project first sought to measure current through the transformer windings more accurately and to reduce the influence of signals from outside the experiment, operating sensors near the limits of their ranges, and non-linearity in the sensors. After dealing with these external factors and getting accurate values for the current, the project aimed at figuring out the impedance of transformer more accurately. However, during data processing, the impedance was found to be varying under different operating conditions. Hence, there was a need to explore further the characteristics of the impedance of the transformer. After several tests and analysis of the results, it was found that the impedance of parameters in a T-model equivalent circuit of a transformer depends a lot on the operating condition of the transformer.

=Further work=
In future, there are still several problems that need to be addressed. For instance, there is a need to determine the ideal equivalent circuit of the PMG choke. Additionally, investigations should be conducted on the PMG choke to determine why no saturation reflects on any of its curves yet it has an air gap. Finally, because for a transformer it is hard to modify the operating condition of a transformer to a specified value by using a variac or a signal generator with an amplifier, research is needed to determine what device can provide reliable input voltage source for the measurement of parameters

=References=
[1] Chandima de Silva, “Measurement and Estimation of Transformer Parameter”,
School of Electrical and Electronic Engineering, University of Adelaide, SA, 2014.

[2] David Nguyen Minh, “Measurement and Estimation of Transformer Parameter”,
School of Electrical and Electronic Engineering, University of Adelaide, SA, 2014.

[3] Kartthikeyen Sivananthan, “Estimation of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2015.

[4] Rahel Bekele Megersa, “Measurement of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2016.

[5] “Project Proposals, Semester 2 2017”, School of Electrical and Electronic
Engineering, University of Adelaide, SA, 2017.

[6] G.R.Slemon and A.Straughen, ELECTRIC MACHINES. 1st Edition. Addison-wesley,
1982 pp20-35

[7] Nurliyana Khazali, “Estimation of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2015.

[8 ] Wildi, T. (1997). Electrical machines, Drives, and Power Systems. 6th ed. pp.20-
220

File:Flow of data.png

2018-06-05T05:22:37Z

A1655751:

Projects:2017s2-291 Measurement of Transformer Parameters

2018-06-05T05:21:18Z

A1655751: /* Method */

=Members=
Yiwei Sun

Zhouyajie xu

Zhi Li

supervisor: Andrew Allison

=Introduction=
A transformer is an electrical device based on Faradays’ law of electromagnetic induction to change alternating voltage, such as increasing or reducing voltage. We are interested in transformer in this project because it is widely be used in power industrial and essential for power transmission over long distance in power grid. Knowing parameters inside transformer will help us understanding the structure of transformer more clearly, and the method used to predict parameters inside transformer is useful for further study measurement which non-linear input and output.
This project also improve our ability of dealing with model, how to fit expected model outcomes with reality outcomes and how to analysis and minimize errors between them.

The aim of this project is mapping the transformer device in figure1.2 with the model of equivalence circuit to get 7 parameters value inside transformer model as “accurate” as possible.
This project is trying to using figure2 to match with figure 1. In another word, comparing our reality measurement of transformer with the theoretical model and analysis error between them.
To summarize the aim of this project:

• Analysis the model in figure 1.1, doing the rough test to get a rough 6 parameters.

• Substitute these rough parameters into transformer model for open circuit, short circuit and cross circuit of transformer to get these input impedance which record as Zin_model

• Measuring the open, short and cross circuit use transformer in figure 1.2 to get input impedance of measure Zin which record as Zin_measure.

• Error analysis between Zin_model and Zin_measure, then optimize error and get final 7 parameters result.

[[File:wiki00.png]]

=Method=
In order to get value of R and X, we measure input voltage and current from port A and port B as one terminal which shows in figure 3.1. From ohms law, the input impedance isZin =Vin/Iin. Splitting the real part and imaginary part of Zin to get R and X value respectively. R=real(Zin), X=imaginary(Zin).

The one-port model which also known as choke is consist of a resistor and inductor.

[[File:Choke one port.png|400px]]

Two-port model is more complicate than one port model, but the method we used to get parameters is similar as one-port model. Doing open circuit and short circuit for primary side (240V) of transformer and secondary side (24V) and two cross connection tests. Each case of these tests can be regard as one-port test and collect Vin and Iin for each test to calculate Zin based on ohms law.
For sub-section Zin model, as we have 6 Zin for open circuit connection, short circuit connection and cross connection, we derive formula for these six Zin based on R1, X1, R2, X2, Rc and Xm then substitute rough parameters we get from section 4 into our derived formula.

[[File:Two_port_test_box.png|400px]]

For measured Zin, the setting up of equipment which including power analyser, oscilloscope for measurement and using varic for power supply. In order to keep current consistency, the Zin for cross connection should be discharged, thus we have 4 Zin to collect. We regarding 4 Zin which has same current as a group, we measure 11 times to get 11 groups of Zin. Actually we have done a lot measurements for these 6 Zin, but only these 11 groups of Zin has the consistency current and useful, I will demonstrate specifically in this sub-section of measured Zin.
The sub-section Matlab method is mainly about the method and approach for data analysis.

=Data analyzing=
To obtain the overall variation of the impedance and to avoid damage to any of the devices, the input voltage range for all AC tests was as large as it could be possible. The Matlab file saturation.m programming for accumulate impedance and plot the curve. From these two curves, it is clear that the impedance of first circuit is varying with the condition of operation with a trend similar to that of the PMG choke. The resistance and reactance didn’t reach the peak value at the same time as well. However, there is no air gap in the two-port transformer and that is the reason why the impedance reached the peak value and decreased sharply instead of staying at the peak value for a wider voltage range. The peak of the curve is where the transformer reaches saturation.
[[File:curve 1.png|400px|border|left|emf vs R curve of two-port #1 test, for 50-240V ]]
[[File:curve 2.png|400px|border|center|emf vs L curve of two-port #1 test, for 50-240V ]]
[[File:curve 3.png|400px|border|right|B-H curve of two-port #1 test, for 50-240V ]]

=Findings=
After data analysis, it was found that the average reactance numerical values of the linear parameters in a T model equivalent circuit strongly depend on the operating condition of the transformer.
In addition, the following findings were made in this project:

• The impedance of a PMG choke does not stay constant after reaching the maximum value during varying operating conditions.

• The equivalent circuit of a PMG choke is not only a resistor and an inductor in series. Or there are huge error occurred during measurement.

• Resistance and reactance do not reach the peak value in the same operating condition.

• Impedance of a transformer remains constant if the current through its windings is maintained at the same value.

• Resistance slightly depends on the operating condition after saturation.

=Conclusion=
This project first sought to measure current through the transformer windings more accurately and to reduce the influence of signals from outside the experiment, operating sensors near the limits of their ranges, and non-linearity in the sensors. After dealing with these external factors and getting accurate values for the current, the project aimed at figuring out the impedance of transformer more accurately. However, during data processing, the impedance was found to be varying under different operating conditions. Hence, there was a need to explore further the characteristics of the impedance of the transformer. After several tests and analysis of the results, it was found that the impedance of parameters in a T-model equivalent circuit of a transformer depends a lot on the operating condition of the transformer.

=Further work=
In future, there are still several problems that need to be addressed. For instance, there is a need to determine the ideal equivalent circuit of the PMG choke. Additionally, investigations should be conducted on the PMG choke to determine why no saturation reflects on any of its curves yet it has an air gap. Finally, because for a transformer it is hard to modify the operating condition of a transformer to a specified value by using a variac or a signal generator with an amplifier, research is needed to determine what device can provide reliable input voltage source for the measurement of parameters

=References=
[1] Chandima de Silva, “Measurement and Estimation of Transformer Parameter”,
School of Electrical and Electronic Engineering, University of Adelaide, SA, 2014.

[2] David Nguyen Minh, “Measurement and Estimation of Transformer Parameter”,
School of Electrical and Electronic Engineering, University of Adelaide, SA, 2014.

[3] Kartthikeyen Sivananthan, “Estimation of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2015.

[4] Rahel Bekele Megersa, “Measurement of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2016.

[5] “Project Proposals, Semester 2 2017”, School of Electrical and Electronic
Engineering, University of Adelaide, SA, 2017.

[6] G.R.Slemon and A.Straughen, ELECTRIC MACHINES. 1st Edition. Addison-wesley,
1982 pp20-35

[7] Nurliyana Khazali, “Estimation of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2015.

[8 ] Wildi, T. (1997). Electrical machines, Drives, and Power Systems. 6th ed. pp.20-
220

File:Two port test box.png

2018-06-05T05:19:31Z

A1655751:

Projects:2017s2-291 Measurement of Transformer Parameters

2018-06-05T05:17:10Z

A1655751: /* Method */

=Introduction=
A transformer is an electrical device based on Faradays’ law of electromagnetic induction to change alternating voltage, such as increasing or reducing voltage. We are interested in transformer in this project because it is widely be used in power industrial and essential for power transmission over long distance in power grid. Knowing parameters inside transformer will help us understanding the structure of transformer more clearly, and the method used to predict parameters inside transformer is useful for further study measurement which non-linear input and output.
This project also improve our ability of dealing with model, how to fit expected model outcomes with reality outcomes and how to analysis and minimize errors between them.

The aim of this project is mapping the transformer device in figure1.2 with the model of equivalence circuit to get 7 parameters value inside transformer model as “accurate” as possible.
This project is trying to using figure2 to match with figure 1. In another word, comparing our reality measurement of transformer with the theoretical model and analysis error between them.
To summarize the aim of this project:

• Analysis the model in figure 1.1, doing the rough test to get a rough 6 parameters.

• Substitute these rough parameters into transformer model for open circuit, short circuit and cross circuit of transformer to get these input impedance which record as Zin_model

• Measuring the open, short and cross circuit use transformer in figure 1.2 to get input impedance of measure Zin which record as Zin_measure.

• Error analysis between Zin_model and Zin_measure, then optimize error and get final 7 parameters result.

[[File:wiki00.png]]

=Method=
In order to get value of R and X, we measure input voltage and current from port A and port B as one terminal which shows in figure 3.1. From ohms law, the input impedance isZin =Vin/Iin. Splitting the real part and imaginary part of Zin to get R and X value respectively. R=real(Zin), X=imaginary(Zin).

The one-port model which also known as choke is consist of a resistor and inductor.

[[File:Choke one port.png|400px]]

Two-port model is more complicate than one port model, but the method we used to get parameters is similar as one-port model. Doing open circuit and short circuit for primary side (240V) of transformer and secondary side (24V) and two cross connection tests. Each case of these tests can be regard as one-port test and collect Vin and Iin for each test to calculate Zin based on ohms law.
For sub-section Zin model, as we have 6 Zin for open circuit connection, short circuit connection and cross connection, we derive formula for these six Zin based on R1, X1, R2, X2, Rc and Xm then substitute rough parameters we get from section 4 into our derived formula.

For measured Zin, the setting up of equipment which including power analyser, oscilloscope for measurement and using varic for power supply. In order to keep current consistency, the Zin for cross connection should be discharged, thus we have 4 Zin to collect. We regarding 4 Zin which has same current as a group, we measure 11 times to get 11 groups of Zin. Actually we have done a lot measurements for these 6 Zin, but only these 11 groups of Zin has the consistency current and useful, I will demonstrate specifically in this sub-section of measured Zin.
The sub-section Matlab method is mainly about the method and approach for data analysis.

=Data analyzing=
To obtain the overall variation of the impedance and to avoid damage to any of the devices, the input voltage range for all AC tests was as large as it could be possible. The Matlab file saturation.m programming for accumulate impedance and plot the curve.
[[File:curve 1.png|400px|emf vs R curve of two-port #1 test, for 50-240V ]]

=Findings=
After data analysis, it was found that the average reactance numerical values of the linear parameters in a T model equivalent circuit strongly depend on the operating condition of the transformer.
In addition, the following findings were made in this project:

• The impedance of a PMG choke does not stay constant after reaching the maximum value during varying operating conditions.

• The equivalent circuit of a PMG choke is not only a resistor and an inductor in series. Or there are huge error occurred during measurement.

• Resistance and reactance do not reach the peak value in the same operating condition.

• Impedance of a transformer remains constant if the current through its windings is maintained at the same value.

• Resistance slightly depends on the operating condition after saturation.

=Conclusion=
This project first sought to measure current through the transformer windings more accurately and to reduce the influence of signals from outside the experiment, operating sensors near the limits of their ranges, and non-linearity in the sensors. After dealing with these external factors and getting accurate values for the current, the project aimed at figuring out the impedance of transformer more accurately. However, during data processing, the impedance was found to be varying under different operating conditions. Hence, there was a need to explore further the characteristics of the impedance of the transformer. After several tests and analysis of the results, it was found that the impedance of parameters in a T-model equivalent circuit of a transformer depends a lot on the operating condition of the transformer.

=Further work=
In future, there are still several problems that need to be addressed. For instance, there is a need to determine the ideal equivalent circuit of the PMG choke. Additionally, investigations should be conducted on the PMG choke to determine why no saturation reflects on any of its curves yet it has an air gap. Finally, because for a transformer it is hard to modify the operating condition of a transformer to a specified value by using a variac or a signal generator with an amplifier, research is needed to determine what device can provide reliable input voltage source for the measurement of parameters

=References=
[1] Chandima de Silva, “Measurement and Estimation of Transformer Parameter”,
School of Electrical and Electronic Engineering, University of Adelaide, SA, 2014.

[2] David Nguyen Minh, “Measurement and Estimation of Transformer Parameter”,
School of Electrical and Electronic Engineering, University of Adelaide, SA, 2014.

[3] Kartthikeyen Sivananthan, “Estimation of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2015.

[4] Rahel Bekele Megersa, “Measurement of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2016.

[5] “Project Proposals, Semester 2 2017”, School of Electrical and Electronic
Engineering, University of Adelaide, SA, 2017.

[6] G.R.Slemon and A.Straughen, ELECTRIC MACHINES. 1st Edition. Addison-wesley,
1982 pp20-35

[7] Nurliyana Khazali, “Estimation of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2015.

[8 ] Wildi, T. (1997). Electrical machines, Drives, and Power Systems. 6th ed. pp.20-
220

Projects:2017s2-291 Measurement of Transformer Parameters

2018-06-05T05:16:38Z

A1655751: /* Method */

=Introduction=
A transformer is an electrical device based on Faradays’ law of electromagnetic induction to change alternating voltage, such as increasing or reducing voltage. We are interested in transformer in this project because it is widely be used in power industrial and essential for power transmission over long distance in power grid. Knowing parameters inside transformer will help us understanding the structure of transformer more clearly, and the method used to predict parameters inside transformer is useful for further study measurement which non-linear input and output.
This project also improve our ability of dealing with model, how to fit expected model outcomes with reality outcomes and how to analysis and minimize errors between them.

The aim of this project is mapping the transformer device in figure1.2 with the model of equivalence circuit to get 7 parameters value inside transformer model as “accurate” as possible.
This project is trying to using figure2 to match with figure 1. In another word, comparing our reality measurement of transformer with the theoretical model and analysis error between them.
To summarize the aim of this project:

• Analysis the model in figure 1.1, doing the rough test to get a rough 6 parameters.

• Substitute these rough parameters into transformer model for open circuit, short circuit and cross circuit of transformer to get these input impedance which record as Zin_model

• Measuring the open, short and cross circuit use transformer in figure 1.2 to get input impedance of measure Zin which record as Zin_measure.

• Error analysis between Zin_model and Zin_measure, then optimize error and get final 7 parameters result.

[[File:wiki00.png]]

=Method=
In order to get value of R and X, we measure input voltage and current from port A and port B as one terminal which shows in figure 3.1. From ohms law, the input impedance isZin =Vin/Iin. Splitting the real part and imaginary part of Zin to get R and X value respectively. R=real(Zin), X=imaginary(Zin).

The one-port model which also known as choke is consist of a resistor and inductor.
[[File:Choke one port.png|400px]]

Two-port model is more complicate than one port model, but the method we used to get parameters is similar as one-port model. Doing open circuit and short circuit for primary side (240V) of transformer and secondary side (24V) and two cross connection tests. Each case of these tests can be regard as one-port test and collect Vin and Iin for each test to calculate Zin based on ohms law.
For sub-section Zin model, as we have 6 Zin for open circuit connection, short circuit connection and cross connection, we derive formula for these six Zin based on R1, X1, R2, X2, Rc and Xm then substitute rough parameters we get from section 4 into our derived formula.

For measured Zin, the setting up of equipment which including power analyser, oscilloscope for measurement and using varic for power supply. In order to keep current consistency, the Zin for cross connection should be discharged, thus we have 4 Zin to collect. We regarding 4 Zin which has same current as a group, we measure 11 times to get 11 groups of Zin. Actually we have done a lot measurements for these 6 Zin, but only these 11 groups of Zin has the consistency current and useful, I will demonstrate specifically in this sub-section of measured Zin.
The sub-section Matlab method is mainly about the method and approach for data analysis.

=Data analyzing=
To obtain the overall variation of the impedance and to avoid damage to any of the devices, the input voltage range for all AC tests was as large as it could be possible. The Matlab file saturation.m programming for accumulate impedance and plot the curve.
[[File:curve 1.png|400px|emf vs R curve of two-port #1 test, for 50-240V ]]

=Findings=
After data analysis, it was found that the average reactance numerical values of the linear parameters in a T model equivalent circuit strongly depend on the operating condition of the transformer.
In addition, the following findings were made in this project:

• The impedance of a PMG choke does not stay constant after reaching the maximum value during varying operating conditions.

• The equivalent circuit of a PMG choke is not only a resistor and an inductor in series. Or there are huge error occurred during measurement.

• Resistance and reactance do not reach the peak value in the same operating condition.

• Impedance of a transformer remains constant if the current through its windings is maintained at the same value.

• Resistance slightly depends on the operating condition after saturation.

=Conclusion=
This project first sought to measure current through the transformer windings more accurately and to reduce the influence of signals from outside the experiment, operating sensors near the limits of their ranges, and non-linearity in the sensors. After dealing with these external factors and getting accurate values for the current, the project aimed at figuring out the impedance of transformer more accurately. However, during data processing, the impedance was found to be varying under different operating conditions. Hence, there was a need to explore further the characteristics of the impedance of the transformer. After several tests and analysis of the results, it was found that the impedance of parameters in a T-model equivalent circuit of a transformer depends a lot on the operating condition of the transformer.

=Further work=
In future, there are still several problems that need to be addressed. For instance, there is a need to determine the ideal equivalent circuit of the PMG choke. Additionally, investigations should be conducted on the PMG choke to determine why no saturation reflects on any of its curves yet it has an air gap. Finally, because for a transformer it is hard to modify the operating condition of a transformer to a specified value by using a variac or a signal generator with an amplifier, research is needed to determine what device can provide reliable input voltage source for the measurement of parameters

=References=
[1] Chandima de Silva, “Measurement and Estimation of Transformer Parameter”,
School of Electrical and Electronic Engineering, University of Adelaide, SA, 2014.

[2] David Nguyen Minh, “Measurement and Estimation of Transformer Parameter”,
School of Electrical and Electronic Engineering, University of Adelaide, SA, 2014.

[3] Kartthikeyen Sivananthan, “Estimation of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2015.

[4] Rahel Bekele Megersa, “Measurement of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2016.

[5] “Project Proposals, Semester 2 2017”, School of Electrical and Electronic
Engineering, University of Adelaide, SA, 2017.

[6] G.R.Slemon and A.Straughen, ELECTRIC MACHINES. 1st Edition. Addison-wesley,
1982 pp20-35

[7] Nurliyana Khazali, “Estimation of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2015.

[8 ] Wildi, T. (1997). Electrical machines, Drives, and Power Systems. 6th ed. pp.20-
220

Projects:2017s2-291 Measurement of Transformer Parameters

2018-06-05T05:15:11Z

A1655751: /* Method */

=Introduction=
A transformer is an electrical device based on Faradays’ law of electromagnetic induction to change alternating voltage, such as increasing or reducing voltage. We are interested in transformer in this project because it is widely be used in power industrial and essential for power transmission over long distance in power grid. Knowing parameters inside transformer will help us understanding the structure of transformer more clearly, and the method used to predict parameters inside transformer is useful for further study measurement which non-linear input and output.
This project also improve our ability of dealing with model, how to fit expected model outcomes with reality outcomes and how to analysis and minimize errors between them.

The aim of this project is mapping the transformer device in figure1.2 with the model of equivalence circuit to get 7 parameters value inside transformer model as “accurate” as possible.
This project is trying to using figure2 to match with figure 1. In another word, comparing our reality measurement of transformer with the theoretical model and analysis error between them.
To summarize the aim of this project:

• Analysis the model in figure 1.1, doing the rough test to get a rough 6 parameters.

• Substitute these rough parameters into transformer model for open circuit, short circuit and cross circuit of transformer to get these input impedance which record as Zin_model

• Measuring the open, short and cross circuit use transformer in figure 1.2 to get input impedance of measure Zin which record as Zin_measure.

• Error analysis between Zin_model and Zin_measure, then optimize error and get final 7 parameters result.

[[File:wiki00.png]]

=Method=
In order to get value of R and X, we measure input voltage and current from port A and port B as one terminal which shows in figure 3.1. From ohms law, the input impedance isZin =Vin/Iin. Splitting the real part and imaginary part of Zin to get R and X value respectively. R=real(Zin), X=imaginary(Zin).

The one-port model which also known as choke is consist of a resistor and inductor.

Two-port model is more complicate than one port model, but the method we used to get parameters is similar as one-port model. Doing open circuit and short circuit for primary side (240V) of transformer and secondary side (24V) and two cross connection tests. Each case of these tests can be regard as one-port test and collect Vin and Iin for each test to calculate Zin based on ohms law.
For sub-section Zin model, as we have 6 Zin for open circuit connection, short circuit connection and cross connection, we derive formula for these six Zin based on R1, X1, R2, X2, Rc and Xm then substitute rough parameters we get from section 4 into our derived formula.

For measured Zin, the setting up of equipment which including power analyser, oscilloscope for measurement and using varic for power supply. In order to keep current consistency, the Zin for cross connection should be discharged, thus we have 4 Zin to collect. We regarding 4 Zin which has same current as a group, we measure 11 times to get 11 groups of Zin. Actually we have done a lot measurements for these 6 Zin, but only these 11 groups of Zin has the consistency current and useful, I will demonstrate specifically in this sub-section of measured Zin.
The sub-section Matlab method is mainly about the method and approach for data analysis.

=Data analyzing=
To obtain the overall variation of the impedance and to avoid damage to any of the devices, the input voltage range for all AC tests was as large as it could be possible. The Matlab file saturation.m programming for accumulate impedance and plot the curve.
[[File:curve 1.png|400px|emf vs R curve of two-port #1 test, for 50-240V ]]

=Findings=
After data analysis, it was found that the average reactance numerical values of the linear parameters in a T model equivalent circuit strongly depend on the operating condition of the transformer.
In addition, the following findings were made in this project:

• The impedance of a PMG choke does not stay constant after reaching the maximum value during varying operating conditions.

• The equivalent circuit of a PMG choke is not only a resistor and an inductor in series. Or there are huge error occurred during measurement.

• Resistance and reactance do not reach the peak value in the same operating condition.

• Impedance of a transformer remains constant if the current through its windings is maintained at the same value.

• Resistance slightly depends on the operating condition after saturation.

=Conclusion=
This project first sought to measure current through the transformer windings more accurately and to reduce the influence of signals from outside the experiment, operating sensors near the limits of their ranges, and non-linearity in the sensors. After dealing with these external factors and getting accurate values for the current, the project aimed at figuring out the impedance of transformer more accurately. However, during data processing, the impedance was found to be varying under different operating conditions. Hence, there was a need to explore further the characteristics of the impedance of the transformer. After several tests and analysis of the results, it was found that the impedance of parameters in a T-model equivalent circuit of a transformer depends a lot on the operating condition of the transformer.

=Further work=
In future, there are still several problems that need to be addressed. For instance, there is a need to determine the ideal equivalent circuit of the PMG choke. Additionally, investigations should be conducted on the PMG choke to determine why no saturation reflects on any of its curves yet it has an air gap. Finally, because for a transformer it is hard to modify the operating condition of a transformer to a specified value by using a variac or a signal generator with an amplifier, research is needed to determine what device can provide reliable input voltage source for the measurement of parameters

=References=
[1] Chandima de Silva, “Measurement and Estimation of Transformer Parameter”,
School of Electrical and Electronic Engineering, University of Adelaide, SA, 2014.

[2] David Nguyen Minh, “Measurement and Estimation of Transformer Parameter”,
School of Electrical and Electronic Engineering, University of Adelaide, SA, 2014.

[3] Kartthikeyen Sivananthan, “Estimation of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2015.

[4] Rahel Bekele Megersa, “Measurement of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2016.

[5] “Project Proposals, Semester 2 2017”, School of Electrical and Electronic
Engineering, University of Adelaide, SA, 2017.

[6] G.R.Slemon and A.Straughen, ELECTRIC MACHINES. 1st Edition. Addison-wesley,
1982 pp20-35

[7] Nurliyana Khazali, “Estimation of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2015.

[8 ] Wildi, T. (1997). Electrical machines, Drives, and Power Systems. 6th ed. pp.20-
220

Projects:2017s2-291 Measurement of Transformer Parameters

2018-06-05T05:13:44Z

A1655751: /* Method */

=Introduction=
A transformer is an electrical device based on Faradays’ law of electromagnetic induction to change alternating voltage, such as increasing or reducing voltage. We are interested in transformer in this project because it is widely be used in power industrial and essential for power transmission over long distance in power grid. Knowing parameters inside transformer will help us understanding the structure of transformer more clearly, and the method used to predict parameters inside transformer is useful for further study measurement which non-linear input and output.
This project also improve our ability of dealing with model, how to fit expected model outcomes with reality outcomes and how to analysis and minimize errors between them.

The aim of this project is mapping the transformer device in figure1.2 with the model of equivalence circuit to get 7 parameters value inside transformer model as “accurate” as possible.
This project is trying to using figure2 to match with figure 1. In another word, comparing our reality measurement of transformer with the theoretical model and analysis error between them.
To summarize the aim of this project:

• Analysis the model in figure 1.1, doing the rough test to get a rough 6 parameters.

• Substitute these rough parameters into transformer model for open circuit, short circuit and cross circuit of transformer to get these input impedance which record as Zin_model

• Measuring the open, short and cross circuit use transformer in figure 1.2 to get input impedance of measure Zin which record as Zin_measure.

• Error analysis between Zin_model and Zin_measure, then optimize error and get final 7 parameters result.

[[File:wiki00.png]]

=Method=
In order to get value of R and X, we measure input voltage and current from port A and port B as one terminal which shows in figure 3.1. From ohms law, the input impedance isZin =Vin/Iin. Splitting the real part and imaginary part of Zin to get R and X value respectively. R=real(Zin), X=imaginary(Zin).

The one-port model which also known as choke is consist of a resistor and inductor.

[[File:Choke one port.png]]

Two-port model is more complicate than one port model, but the method we used to get parameters is similar as one-port model. Doing open circuit and short circuit for primary side (240V) of transformer and secondary side (24V) and two cross connection tests. Each case of these tests can be regard as one-port test and collect Vin and Iin for each test to calculate Zin based on ohms law.
For sub-section Zin model, as we have 6 Zin for open circuit connection, short circuit connection and cross connection, we derive formula for these six Zin based on R1, X1, R2, X2, Rc and Xm then substitute rough parameters we get from section 4 into our derived formula.

For measured Zin, the setting up of equipment which including power analyser, oscilloscope for measurement and using varic for power supply. In order to keep current consistency, the Zin for cross connection should be discharged, thus we have 4 Zin to collect. We regarding 4 Zin which has same current as a group, we measure 11 times to get 11 groups of Zin. Actually we have done a lot measurements for these 6 Zin, but only these 11 groups of Zin has the consistency current and useful, I will demonstrate specifically in this sub-section of measured Zin.
The sub-section Matlab method is mainly about the method and approach for data analysis.

=Data analyzing=
To obtain the overall variation of the impedance and to avoid damage to any of the devices, the input voltage range for all AC tests was as large as it could be possible. The Matlab file saturation.m programming for accumulate impedance and plot the curve.
[[File:curve 1.png|200px|thumb|left|emf vs R curve of two-port #1 test, for 50-240V ]]

=Findings=
After data analysis, it was found that the average reactance numerical values of the linear parameters in a T model equivalent circuit strongly depend on the operating condition of the transformer.
In addition, the following findings were made in this project:

• The impedance of a PMG choke does not stay constant after reaching the maximum value during varying operating conditions.

• The equivalent circuit of a PMG choke is not only a resistor and an inductor in series. Or there are huge error occurred during measurement.

• Resistance and reactance do not reach the peak value in the same operating condition.

• Impedance of a transformer remains constant if the current through its windings is maintained at the same value.

• Resistance slightly depends on the operating condition after saturation.

=Conclusion=
This project first sought to measure current through the transformer windings more accurately and to reduce the influence of signals from outside the experiment, operating sensors near the limits of their ranges, and non-linearity in the sensors. After dealing with these external factors and getting accurate values for the current, the project aimed at figuring out the impedance of transformer more accurately. However, during data processing, the impedance was found to be varying under different operating conditions. Hence, there was a need to explore further the characteristics of the impedance of the transformer. After several tests and analysis of the results, it was found that the impedance of parameters in a T-model equivalent circuit of a transformer depends a lot on the operating condition of the transformer.

=Further work=
In future, there are still several problems that need to be addressed. For instance, there is a need to determine the ideal equivalent circuit of the PMG choke. Additionally, investigations should be conducted on the PMG choke to determine why no saturation reflects on any of its curves yet it has an air gap. Finally, because for a transformer it is hard to modify the operating condition of a transformer to a specified value by using a variac or a signal generator with an amplifier, research is needed to determine what device can provide reliable input voltage source for the measurement of parameters

=References=
[1] Chandima de Silva, “Measurement and Estimation of Transformer Parameter”,
School of Electrical and Electronic Engineering, University of Adelaide, SA, 2014.

[2] David Nguyen Minh, “Measurement and Estimation of Transformer Parameter”,
School of Electrical and Electronic Engineering, University of Adelaide, SA, 2014.

[3] Kartthikeyen Sivananthan, “Estimation of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2015.

[4] Rahel Bekele Megersa, “Measurement of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2016.

[5] “Project Proposals, Semester 2 2017”, School of Electrical and Electronic
Engineering, University of Adelaide, SA, 2017.

[6] G.R.Slemon and A.Straughen, ELECTRIC MACHINES. 1st Edition. Addison-wesley,
1982 pp20-35

[7] Nurliyana Khazali, “Estimation of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2015.

[8 ] Wildi, T. (1997). Electrical machines, Drives, and Power Systems. 6th ed. pp.20-
220

Projects:2017s2-291 Measurement of Transformer Parameters

2018-06-05T05:13:33Z

A1655751: /* Method */

=Introduction=
A transformer is an electrical device based on Faradays’ law of electromagnetic induction to change alternating voltage, such as increasing or reducing voltage. We are interested in transformer in this project because it is widely be used in power industrial and essential for power transmission over long distance in power grid. Knowing parameters inside transformer will help us understanding the structure of transformer more clearly, and the method used to predict parameters inside transformer is useful for further study measurement which non-linear input and output.
This project also improve our ability of dealing with model, how to fit expected model outcomes with reality outcomes and how to analysis and minimize errors between them.

The aim of this project is mapping the transformer device in figure1.2 with the model of equivalence circuit to get 7 parameters value inside transformer model as “accurate” as possible.
This project is trying to using figure2 to match with figure 1. In another word, comparing our reality measurement of transformer with the theoretical model and analysis error between them.
To summarize the aim of this project:

• Analysis the model in figure 1.1, doing the rough test to get a rough 6 parameters.

• Substitute these rough parameters into transformer model for open circuit, short circuit and cross circuit of transformer to get these input impedance which record as Zin_model

• Measuring the open, short and cross circuit use transformer in figure 1.2 to get input impedance of measure Zin which record as Zin_measure.

• Error analysis between Zin_model and Zin_measure, then optimize error and get final 7 parameters result.

[[File:wiki00.png]]

=Method=
In order to get value of R and X, we measure input voltage and current from port A and port B as one terminal which shows in figure 3.1. From ohms law, the input impedance isZin =Vin/Iin. Splitting the real part and imaginary part of Zin to get R and X value respectively. R=real(Zin), X=imaginary(Zin).

The one-port model which also known as choke is consist of a resistor and inductor.
[[File:Choke one port.png]]

Two-port model is more complicate than one port model, but the method we used to get parameters is similar as one-port model. Doing open circuit and short circuit for primary side (240V) of transformer and secondary side (24V) and two cross connection tests. Each case of these tests can be regard as one-port test and collect Vin and Iin for each test to calculate Zin based on ohms law.
For sub-section Zin model, as we have 6 Zin for open circuit connection, short circuit connection and cross connection, we derive formula for these six Zin based on R1, X1, R2, X2, Rc and Xm then substitute rough parameters we get from section 4 into our derived formula.

For measured Zin, the setting up of equipment which including power analyser, oscilloscope for measurement and using varic for power supply. In order to keep current consistency, the Zin for cross connection should be discharged, thus we have 4 Zin to collect. We regarding 4 Zin which has same current as a group, we measure 11 times to get 11 groups of Zin. Actually we have done a lot measurements for these 6 Zin, but only these 11 groups of Zin has the consistency current and useful, I will demonstrate specifically in this sub-section of measured Zin.
The sub-section Matlab method is mainly about the method and approach for data analysis.

=Data analyzing=
To obtain the overall variation of the impedance and to avoid damage to any of the devices, the input voltage range for all AC tests was as large as it could be possible. The Matlab file saturation.m programming for accumulate impedance and plot the curve.
[[File:curve 1.png|200px|thumb|left|emf vs R curve of two-port #1 test, for 50-240V ]]

=Findings=
After data analysis, it was found that the average reactance numerical values of the linear parameters in a T model equivalent circuit strongly depend on the operating condition of the transformer.
In addition, the following findings were made in this project:

• The impedance of a PMG choke does not stay constant after reaching the maximum value during varying operating conditions.

• The equivalent circuit of a PMG choke is not only a resistor and an inductor in series. Or there are huge error occurred during measurement.

• Resistance and reactance do not reach the peak value in the same operating condition.

• Impedance of a transformer remains constant if the current through its windings is maintained at the same value.

• Resistance slightly depends on the operating condition after saturation.

=Conclusion=
This project first sought to measure current through the transformer windings more accurately and to reduce the influence of signals from outside the experiment, operating sensors near the limits of their ranges, and non-linearity in the sensors. After dealing with these external factors and getting accurate values for the current, the project aimed at figuring out the impedance of transformer more accurately. However, during data processing, the impedance was found to be varying under different operating conditions. Hence, there was a need to explore further the characteristics of the impedance of the transformer. After several tests and analysis of the results, it was found that the impedance of parameters in a T-model equivalent circuit of a transformer depends a lot on the operating condition of the transformer.

=Further work=
In future, there are still several problems that need to be addressed. For instance, there is a need to determine the ideal equivalent circuit of the PMG choke. Additionally, investigations should be conducted on the PMG choke to determine why no saturation reflects on any of its curves yet it has an air gap. Finally, because for a transformer it is hard to modify the operating condition of a transformer to a specified value by using a variac or a signal generator with an amplifier, research is needed to determine what device can provide reliable input voltage source for the measurement of parameters

=References=
[1] Chandima de Silva, “Measurement and Estimation of Transformer Parameter”,
School of Electrical and Electronic Engineering, University of Adelaide, SA, 2014.

[2] David Nguyen Minh, “Measurement and Estimation of Transformer Parameter”,
School of Electrical and Electronic Engineering, University of Adelaide, SA, 2014.

[3] Kartthikeyen Sivananthan, “Estimation of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2015.

[4] Rahel Bekele Megersa, “Measurement of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2016.

[5] “Project Proposals, Semester 2 2017”, School of Electrical and Electronic
Engineering, University of Adelaide, SA, 2017.

[6] G.R.Slemon and A.Straughen, ELECTRIC MACHINES. 1st Edition. Addison-wesley,
1982 pp20-35

[7] Nurliyana Khazali, “Estimation of Transformer Parameters”, School of
Electrical and Electronic Engineering, University of Adelaide, SA, 2015.

[8 ] Wildi, T. (1997). Electrical machines, Drives, and Power Systems. 6th ed. pp.20-
220

File:Choke one port.png

2018-06-05T05:12:42Z

A1655751: