A Solid-State Circuit Breaker Based on Si-IGBT and SiC MOSFET Hybrid Switch with Self-delay Gate Driver Circuits

Solid state circuit breaker (SSCB) has the advantages of high response speed, high life time, etc., which is the key equipment for DC system short circuit fault clearance. In this paper, a SSCB based on hybrid switch connecting SiC MOSFET and Si IGBT in parallel and controlled by a single drive signal is proposed. The load current is carried by SiC MOSFET. When a fault occurs, the current is transferred to the IGBT branch for turning-off. It combines the advantages of low loss of SiC MOSFET and higher short circuit withstand capability of IGBT. The proposed driver circuit uses RC delay and BJT to achieve IGBT turn-off with delay, and only one driver is needed to control two parallel SiC MOSFET and IGBT, which is simple and reliable. The working principle of hybrid switch SSCB and self-delay driver is analyzed. The Pspice-based simulation model is constructed, and the simulation results show that the parallel IGBT driver can increase the withstand ability of SSCB for short-circuit current, and the proposed driver can reliably turn off the IGBT with a time delay, which is also meaningful for reducing the cost of SSCBs.