Robust Design and Performance Evaluation of High-Speed Overcurrent and Short-Circuit Protection Circuits for SiC Power Semiconductors

SiC MOSFETs have been actively studied in various applications because of their high switching frequency and low on-resistance. However, SiC MOSFETs have a short withstand time in case of short circuit, and the protection circuit malfunctions because of switching noise generated in the transient state. Therefore, the protection circuit of SiC MOSFETs must be designed to have fast short-circuit protection and switching noise immunity and respond quickly to overcurrent situations. In this paper, the design of a proposed protection circuit is presented through transient section analysis of SiC MOSFETs. The proposed circuit has high reliability in dark short-circuit conditions as well as overcurrent detection and ensures stable operation by securing sufficient margin between the drain-source sensing voltage and the trigger voltage. The performance of this circuit is verified under various fault situations through Double Pulse Test (DPT) experiments.