Surge Voltage Suppression using Dual MOVs and Modified RC Snubber Circuit Structure in a DC Solid-State Circuit Breaker

This paper proposes a new snubber circuit to suppress surge voltage generated during SiC MOSFET turn-off in DC solid-state circuit breakers (SSCB). The proposed circuit adopts two MOVs of different clamping voltage ratings to use their energy absorption difference. Each MOV plays a role in voltage clamping and energy absorption, respectively, based on the difference in operating voltage. The validity of the proposed approach is verified by simulation. Compared to the conventional methods, it performs well in reducing surge voltage on DC SSCB.