Temperature Characteristics and Feasibility Study of Temperature-Sensitive Electrical Parameters under Short-Circuit Conditions for SiC MOSFETs

To address the persistent challenge of thermal stress, the leading cause of SiC MOSFET failure, it is essential to enhance their field robustness and extend their lifespan through precise junction temperature prediction and timely fault protection. Temperature-Sensitive Electrical Parameters (TSEPs) are commonly employed for temperature monitoring; however, they often face limitations such as low resolution and high detection difficulty, which can undermine the accuracy of temperature predictions. Additionally, short circuits represent an extreme condition for temperature rise, and it is imperative to verify the stability of their indicators under high-temperature conditions. This study investigates the temperature dependence of dynamic parameters in SiC MOSFETs under short-circuit scenarios. By comparing TSEPs under normal and short-circuit conditions, a new TSEP is proposed, accompanied by the design of a novel data acquisition circuit for in-situ temperature prediction. Furthermore, this study offers guidance for selecting short-circuit protection sensors, effectively preventing false triggers caused by temperature fluctuations.