The application of active superconducting DC fault current limiter in hybrid AC/DC power supply systems

This paper presents a new topology of the active superconducting DC fault current limiter (DC-SFCL) applied in the hybrid AC/DC power supply systems. The proposed DC-SFCL is composed of superconducting transformer, DC chopper and voltage source converter (VSC). The primary winding of the transformer is connected in series with DC transmission line, and the second winding is connected with AC power system through the VSC and the DC chopper. The active DC-SFCL can suppress the fault current of DC system through power exchange between the DC and the AC system. Moreover, the DC-SFCL can act as an active power filter for both the DC system and the AC system to solve the problem of power quality. Using MATLAB SIMULINK, the simulation model of the hybrid AC/DC power supply systems with the proposed DC-SFCL is created. Simulation results validate the dynamics of system, and the performance of the active DC-SFCL is confirmed.