Research on the SiC MOSFETs Short Circuit Detection and Protection optimization Method

Abstract

In order to ensure the reliable operation of SiC MOSFETs, the short-circuit protection function is critical for the drive board. In this paper, the existing short-circuit protection methods are firstly analyzed and compared, which shows that the desaturation detection method is relatively easy to implement. Secondly, due to the weak short-circuit withstand capability, the traditional desaturation detection circuit is optimized. The parameters selection method and the detection delay time are analyzed in detail. Considering of the temperature sensitivity of drain-source voltage VDS, a temperature compensation desaturation detection circuit is proposed. Finally, the above analysis are verified through simulation and experimental results, which show that the total short-circuit protection time is less than 1 $\mu$s.