Efficient and Compact 400-V, 100-A Solid-State Circuit Breaker Using SiC Devices

This paper presents a solid-state circuit breaker designed to minimize conduction losses and achieve a compact implementation. Solid-state circuit breakers offer faster cutoff speeds and improved repetitive use cycles than mechanical circuit breakers. However, the electrical characteristics of power devices are sensitive to temperature increases, leading to higher on-resistance, dropped conduction efficiency, and decreasing size advantage. This paper examines the effects of the number of parallel devices and temperature rise on conduction loss in a solid-state circuit breaker using SiC devices, which consist of a cascode connection between a Si MOSFET and a SiC JFET. Consequently, the solid-state circuit breaker achieves a conduction efficiency of 99.94% with a comparable implementation with mechanical breakers. Experimental validation is conducted in a 400-V, 100- A DC distribution system.