An Experimental Technique for Detecting False Turn-on of SiC MOSFETs

Due to the increased likelihood of a potential dc bus shoot-through and eventual device failure, detection of false turn-on of SiC MOSFET is essential. However, detecting false turn-on through experiments is challenging due to the difficulty in measuring the actual gate-source voltage and channel current of the device. This paper presents an experimental method to detect the occurrence of false turn-on of SiC MOSFETs when used in a half-bridge configuration. The false turn-on event causes a device overcurrent and slower drain-source voltage transitions, which are used as indicators for the experimental method. The method is verified through DPT experiments and SPICE simulation for a 1.2kV SiC MOSFET for a range of operating conditions.