Next-generation power converter design using wide bandgap power devices

• Main Author: Shang, Shuye
• Other Authors: Tang Yi
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2023
• Subjects: Engineering::Electrical and electronic engineering::Power electronics
• Online Access: https://hdl.handle.net/10356/168069
• Institution: Nanyang Technological University

Silicon-based semiconductor power switching devices have reached their performance limits. In order to meet the energy concept of sustainable development and low-carbon society, we need to further improve the power switching characteristics by researching breakthrough technologies. This study focuses on the wide bandgap (WBG) power devices such as SiC MOSFETs which have the superior electrical characteristics, providing new opportunities for the design of next-generation ultra-high efficiency and ultra-high power density power converters. This project analyzes the power switch tube process and the latest high-frequency switching WBG technology through a multidisciplinary approach to facilitate the design of WBG-based power converters in terms of energy efficiency, power density, and operational reliability. I analyzed the switching principle of power MOSFETs from the internal level, the superiority of wide bangap devices from the microscopic material level. At the same time, I investigated the switching characteristics of Si and SiC MOSFET devices, and established a specific SiC MOSFET switch mathematical model. Due to the high switching speed of these devices, early design optimization in practical engineering applications requires modeling and optimizing the design. This study compares the difference in switching time and switching loss between Si MOSFET and SiC MOSFET in similar situations by LTSpice simulation. This study also provides a mathematical model that can simulate device switching characteristics and analyze the influence of parasitic parameters on the switching process for practical engineering applications. The project aims to promote the future development of wide-bandgap semiconductor power devices, expand their use to new applications, and reduce their cost, making them more and more competitive with traditional silicon-based devices.