Study of DC Superconducting Current-Limiting Switch in MVDC Shipboard Power System

The medium voltage direct current (MVDC) is a promising direction of future shipboard power system (SPS). However, one of the main limitations encountered in its development is the fault isolation of DC side. This paper reveals the evolution process of short-circuit fault in typical MVDC SPS through equivalent circuit and transient simulation. Based on the analysis of protection needs, a superconducting current-limiting switch (SCLS) topology is proposed, which includes one superconducting coupled coil and two DC circuit breakers (DCCBs). The models of SCLS is built on MATLAB/Simulink and the current limiting principle and current sharing principle of SCLS are verified. The results show that the SCLS has effective current limiting performance and fault clearing effect.