Feasible Application Study of Several Types of Superconducting Fault Current Limiters in HVDC Grids

The eventual goal of high-voltage direct-voltage (HVDC) systems is to implement HVDC grids. One of the key obstacles in realization of the HVDC grid is the absence of a dc circuit breaker (DCCB). Several prototypes of DCCBs for the HVDC grid have been proposed, but no commercial solution has been developed yet due to insufficient dc fault current breaking capabilities and an unreliable protection-coordination scheme. In this respect, application of the suitable fault current limiter is necessary, and the use of a superconducting fault current limiter (SFCL), which has already been developed for the ac grid, is a viable solution, but there is no fundamental research about performance evaluation of SFCLs for the dc grid. Therefore, we aim to verify the applicability of the conventional SFCL in HVDC grids and perform a comparative analysis of the performance of several types of SFCLs. To analyze the performance of the conventional SFCL in the HVDC grid, three well-known representative types of SFCLs are modeled in MATLAB/Simulink, and their current limiting and recovery characteristics and energy dissipation are examined in voltage-source converter HVDC system application. From the simulation results, we deduced the strengths and the weakness of different types of SFCLs. Consequently, the likely SFCL candidate for commercialization in dc grid applications is suggested.