Influence of Gate Loop Inductance on TSEP-based Junction Temperature Monitoring for SiC MOSFET

In this paper, the influence of gate loop inductance on the junction temperature monitoring for a silicon carbide metal-oxide-semiconductor field-effect transistor's (SiC MOSFET) based on the measurement of a typical temperature sensitive electrical parameter (TSEP), the transient peak gate current during switching, is investigated. This TSEP versus the junction temperature under different gate loop inductances are studied by means of SPICE simulation and experimental work. A considerable reduction in the peak gate current with increasing gate loop inductance is observed and analyzed. An improved junction temperature model is developed by taking the influence of the gate loop inductance into account, to characterize the influence of both gate loop inductance and junction temperature on the peak gate current. The accuracy of the proposed model is retained even when the gate loop inductance varies by 140%.