Optimization of power loss and thermal performance in electric vehicle propulsion: a comparative analysis of Si, SiC, and GaN MOSFET power converters for EESM-based EVs

This research delves into power loss and thermal dynamics in Si, SiC, and GaN inverters and two-quadrant DC-DC converters for Electric Vehicle (EV) applications with Electrically Excited Synchronous Motors (EESM). Utilizing the Cauer thermal model for dissipating junction temperature through heatsinks, the research unveils semiconductor material performance intricacies. The Si-based inverter exhibits the highest total power loss at 355.49 W, followed by SiC at 164.28 W, and GaN at 139.21 W. The efficiencies of Si, SiC, and GaN-based inverters are calculated as 94.72%, 97.49%, and 97.86%, respectively. Among them, the GaN-based inverter shows the highest efficiency, which is 3.14% higher than that of the Si-based inverter. GaN emerges as the energy-efficient choice, showcasing superior conduction and switching losses for EESM-based EV propulsion. Integration of heatsinks reduces Si average junction temperatures from 199.69 degrees C to 55.63 degrees C, SiC from 93.9 degrees C to 45.97 degrees C, and GaN from 84.13 degrees C to 38.78 degrees C. Enhanced forced cooling and advanced thermal interface materials highlights the critical role of robust thermal management in EESM-based EVs. GaN emerges as the prime candidate for EESM-based EV inverters and DC-DC converters. This research underscores meticulous semiconductor material selection and efficient cooling strategies for optimal performance and reliability.