Projects:2020s2-7531 Wide Bandgap Device in PV Systems
Contents
Wide Bandgap device in PV systems
2. Team members
- Abdulrahmen Alzeer
- Kunqiang (Edward) Zhang
- Bradley Slape
3. Supervisors
* Dr. Nesimi Ertegrul * Dr Said Al-Sarawi
Abstract here
Introduction
This project looks improve the efficiency of solar PV arrays through the use of designing a novel solar arrangement that uses wide bandgap (WBG) transistors to eliminate the use of blocking diodes. Additionally, these cells will be paired with a DC/DC convertor, as a means to perform maximum powerpoint tracking (MPPT).
Project team
Project students
- Abdulrahman Alzeer
- Bradley Slape
- Kunqiang (Edward) Zhang
Supervisors
- Dr. Nesimi Ertugrul
- Dr. Said Al-Sarawi
Objectives
- Investigating WBG devicde with non-inverting buck/boost converter
- Cell-level reconfigure PV array
- Maximum power point tracking algorithm design
- Build up all prototype with all the component above
Background
WBG devices
WBG and ultra-wide bandgap (UWBG) devices (GaN and SiC) have recently emerged in response to the limitations of the conventional Si based switches. For example, WBG devices offer 10 times faster switching speeds than Si devices (hence offering miniaturisation) and can function at higher operating temperatures without active cooling. WBG devices have also lower breakdown voltage and lower and constant on- resistance. Moreover, passive components in the WBG based power circuits can be smaller. Furthermore, their high dv/dt and high di/dt ratings eliminate switching mode snubbers at high operating currents and offering enhanced in-rush current capabilities as well as removing the switching current limits through the freewheeling diodes specifically in half bridge arrangements [5]. A highly effective and high speed dead-zone (near the buck/boost interface) avoidance and mitigation state machine will be studied first in the non-inverting converter. Unlike the other alternatives, this technique does not increase switching loss and operates autonomously independent of external conditions. To overcome the efficiency drop in the cascaded topology, GaN FET and SiC MOSFET can be considered.
Reconfigurable solar PV
A conventional PV module typically contains a number of bypass diodes that connect strings of cells together, these diodes will block these cells from producing power in shaded conditions. however this will come at a loss, with the series resistance and losses associated with the diode having a parasitic drain on the device. The introduction of WBG transistors into the array of cells will allow for the connection of these modules such that shaded cells can isolated from the layout, and any other productive cells can be placed in either series or parallel.
DC-DC Converter
GaN technology has been selected to build the project DC-DC converter. A synchronous DC-DC converter has been built and experimental data have been gathered and compared with simulated data to verify the model we have developed in the computer simulation. The results show correlation between them.
Ltspice has been used as it is free and some of the models used are available in the library of the software.
MPPT Algorithm
The maximum power point tracking algorithm is used to adjust the output voltage of the PV array so that the output power of the whole system is always maintained near the maximum power point. The choice of algorithm should be considered from various aspects, such as efficiency, simplicity, convergence speed and ability to track under partial shading conditions.
Method
Results
The MPPT algorithm has been successfully implemented with a buck converter on simulink. The results show that the MPPT algorithm maintain the system output around the maximum power point.
Conclusion
References
[1] a, b, c, "Simple page", In Proceedings of the Conference of Simpleness, 2010.
[2] Nesimi Ertugrul, WBG Project Description LP2000200443 Final, 2020
[3] Sabrina Titri et al, A new MPPT controller based on the Ant colony optimisation algorithm for Photovoltaic systems under partial shading conditions, Applied Soft Computing, Volume 58, Pages 465-479, September 2017
[4] R. Kalatehjari, A. S. A. Rashid, N. Ali, and M. Hajihassani, "The Contribution of Particle Swarm Optimization to Three-Dimensional Slope Stability Analysis," Swarm Intelligence and Its Applications, June 2014.
[5] N. Ertugrul and D. Abbott, "DC is the Future [Point of View]," in Proceedings of the IEEE, vol. 108, no. 5, pp. 615-624, May 2020, doi: 10.1109/JPROC.2020.2982707.
