Development and parameters optimization of a self-driving fault current limiter

The fault current limiter (FCL) can rapidly and effectively limit the short circuit current with a good application prospect. This paper proposes a new fault current limiter based on self-driving rheostat (SD-FCL) for 5 kV/15 kA applications. It can achieve nearly zero operation loss and fully utilize the energy of short circuit current without any other detection equipment or devices to limit the first half-wave peak of the fault current. Firstly, the basic principle and working process of SD-FCL are analyzed in theory. The characteristics and optimization methods of the key parameters are obtained. And the current limiting performance of SD-FCL on various short circuit faults is verified by power system transient simulation, showing the excellent current limiting effect. Finally, the pro-totype is developed, and the test platform is built to conduct a comparison test between the optimized and unoptimized parameters. The results show that SD-FCL limits the fault current at 4.2 ms when the peak value of the fault current is 15.6 kA. The current limiting depth of the first half-wave peak is 14.7%, and the maximum is 60.1%. Overall, the current limiting effect of SD-FCL is good and may provide feasible solutions for power system fault protection.