Temperature dependence of dynamic performance of SiC MOSFETs in a half-bridge configuration

Abstract

High-temperature robustness of switching device is crucial for the system operation reliability. Given the importance of accurate SiC MOSFET dynamic analysis in high-temperature settings, comprehensive investigations are needed. Thus, this paper delves into the dynamic characteristics of SiC MOSFETs under high temperature conditions. Firstly, a piecewise equivalent circuit model is introduced, which provides a framework for analyzing the switching behavior and the influence of reverse recovery on switching performance. Then, the roles of parameters-threshold voltage, internal gate resistance, and gate to source capacitance are explained in governing the high temperature dynamic performance of SiC MOSFETs. Through systematic testing and analysis, the switching characteristics and reverse recovery performance of three 1.2 kV SiC MOSFETs are carefully evaluated across varying temperatures. According to our study, the reverse recovery phenomenon is identified as the main cause of turn-on performance degradation at high temperatures. Furthermore, the effect of the SiC MOSFET structure on the dynamic behavior is discussed. This work discusses the impact of SiC MOSFET structure on dynamic behavior, specifically in the context of a half-bridge configuration. This assessment deepens understanding of SiC MOSFET behavior at high temperatures, guiding strategies to boost efficiency and reliability in power electronics.