Experimental Validation of Parallel Connection of RB-IGCTs for High Efficiency Solid State Circuit Breaker

The proliferation of high efficiency, high current DC distribution systems is held back by the limited choices when it comes to solid-state circuit breakers. With this work, we investigated the parallel connection of Reverse Blocking IGCTs (RB-IGCT) for a solid-state circuit breaker with a nominal current up to 3 kA. The presented breaker topology is based on the parallel connection of low conduction loss RB-IGCTs which delivers efficiency as high as 99.9%. The focus of his paper is on the design and experimental validation of a parallel connection of two and three RB-IGCTs with an emphasis on current sharing during nominal operation and short circuit transients. The experimental results confirm that the parallel connection of both two and three RB-IGCTs can successfully handle the nominal operation current - up to 3 kA continuously - with current deviation from the mean as little as 1-5%. Moreover, the parallel topology is able to perform current interruption during overload and short-circuit situations up to 10 kA for two devices in parallel and up to 13 kA for three devices in parallel.