A fast acting DC solid state fault isolation device (FID) with Si and SiC devices for MVDC distribution system

This paper presents a low voltage (400V) hardware prototype of a fast acting medium voltage DC circuit breaker. Simulation results obtained using PLECS software and hardware testing results are also presented for the same prototype. The prototype serves as a proof of concept showing implementation of firmware logic capable of interrupting DC fault current within 4.042 micro-seconds from the instant an overcurrent condition occurs. The authors propose that the same concept can be extended to medium voltage DC level and present a performance comparison of real 6.5kV silicon (Si) and 10kV silicon carbide (SiC) devices as solid state fault isolation devices (SSFID) in a medium voltage DC (MVDC) distribution system using SPICE simulations. The MVDC SSFID described in this paper finds an application in MVDC distribution system described by Next Generation Integrated Power System (NGIPS) roadmap [1] proposed by Electric Ship Office (ESO) of Office of Naval Research (ONR). Other applications include large scale grid connected solar and wind farm at MVDC level.