Self-Powered 380 V DC SiC Solid-State Circuit Breaker and Fault Current Limiter

Abstract

This paper presents a new ultrafast dc solid-state circuit breaker (SSCB) that uses a silicon carbide cascode as themain switching and limiting semiconductor and an isolated photovoltaic driver to control it. The proposed topology is self-powered and fully implemented with discrete parts. The SSCB’s cascode can work in three different states—fully ON during nominal operation, linear mode for current limitation, and fully OFF to disconnect the load. The time the SSCB operates in linear mode and the maximum current limit is easily set by discrete components. Control inputs have also been included to reset the SSCB after a fault has been removed or to remotely switch it ON or OFF. This device can be used in dc distribution avoiding deterioration due to the problems associated with electric arcs and mechanical aging of moving parts, limiting inrush currents and also minimizing conduction losses respect other kind of circuit breakers. Functional, thermal, and efficiency tests have been carried out with three different 380 V prototypes. Experimental results show the excellent behavior of the SSCB, it is able to block a 380 V short circuit failure in 570 ns; the authors have not found any faster results in the literature.