Design of an HTS Fault Current Limiting Module for an MVDC Power Grid

We have studied a DC circuit breaker with an HTS fault current limiting (FCL) module for MVDC(Medium-Voltage Direct Current) power grid. The attached FCL module can reduce the burden of the circuit breaker to make the system break the fault current faster as well as safer. In this paper, we will present the design of an HTS fault current limiting module with 2G REBCO conductor for the MVDC power grid with the rated voltage of 15 kV. Among several different type of 2G REBCO conductor from different suppliers, we selected the most suitable conductor, which was SuNAM's stabilizer free REBCO conductor, based on the overcurrent test results. And we performed the circuit simulation to verify the module's validity for rated current of 3 kA in 15 kV class DC grid.