New Simple-Structured AC Solid-State Circuit Breaker

Recently, distributed generators and sensitive loads have been widely used. They enable a solid-state circuit breaker (SSCB), which is an imperative device to get acceptable power quality of ac power grid systems. The existing ac SSCB composed of a silicon-controlled rectifier requires some auxiliary mechanical devices to achieve the reclosing operation before fault recovery. However, the new ac SSCB can achieve a quick breaking operation and then be reclosed with no auxiliary mechanical devices or complex control even under sustained short-circuit fault because the commutation capacitors are charged naturally without any complex control of main thyristors and auxiliary ones. The performance features of the proposed ac SSCB are verified through the experiment results of the short-circuit faults.