Thermal Design of a High-Current Solid State Circuit Breaker for DC Shipboard Power Systems

We present the design and experimental validation of the thermal system for a high-current solid-state circuit breaker. The circuit breaker is designed to support DC distribution systems for all-electric ships, which are an active area of academic research and industrial development. Solid state DC circuit breakers can limit fault current at least one order of magnitude faster than traditional mechanical or hybrid solutions. However, they also have significantly higher loss, making the design of their thermal systems critical to their operation. In addition, high power density, small form factor, and high reliability is a must for shipboard applications. The developed solid state DC circuit breaker was tested with a continuous current up to 1500 A with a resulting power density of 18 MW/m3 per pole at a system voltage up to 1 kV.