High Power Density Design of Power Electronic Interrupter in Hybrid DC Circuit Breaker

Circuit protection is a key enabler for future medium-voltage direct-current (MVDC) distribution systems. Hybrid dc circuit breaker (HCB) offers low conduction losses and reasonably fast response times, but suffers from large size. In this paper, a high power density power electronic interrupter design is introduced for the HCB. The device selection and trade-off analysis of voltage clamping circuit are investigated. A small sized module with two parallel 1.7 kV discrete IGBTs are selected as main switches. The RC snubber and MOV are carefully designed to guarantee no tail current bump and sufficient turn-off voltage margin. Experimental results at 12 kV and 1 kA are provided to verify the operation of the prototype.