Research on a GaN HEMT On-Board Charger for Electric Vehicles Guoen Cao
Hanyang University Graduate School Department of Electronic Systems Engineering
Research on a GaN HEMT On-Board Charger for Electric Vehicles Guoen Cao Dept. of Electronic Systems Engineering The Graduate School Hanyang University With an accelerating global energy crisis and deteriorating environmental problems, electric vehicle (EV) technologies have attracted growing interest due to their reduced fuel usage and greenhouse emissions. The battery charger plays a critical role for the acceptance and development of EVs. Because a battery is generally used as the main power source, a high conversion efficiency, high power density, and lightweight on-board-charger (OBC) is needed in order to maximize the energy utilization. Gallium nitride based high electron-mobility transistors (GaN HEMTs) are potential candidates as next-generation power switching devices due to the enormous potential use in the applications of high frequency, high temperature, and high output power, in particular of battery charger applications. Although much progress has been achieved in the development of GaN HEMTs, a few important issues such as current collapse effects should be evaluated before wide deployment is possible. Since evaluating performance in power semiconductors and selecting the optimal topologies are important steps in the design and development of power electronics circuits, this thesis is concerned with the performance evaluation of the new GaN HEMTs and the design of an isolated OBC that uses GaN HEMTs to achieve high efficiency for future applications in EVs.