A ground fault section location method based on active detection approach for non-effectively grounded DC distribution networks*

Identifying and locating the single-pole-to-ground fault for the non-effectively grounded DC distribution networks is highly challenging due to the topology arrangement limitations and the grounding mode. To solve this problem, a ground fault section location method based on active detection approach is proposed. Firstly, an approach based on an additional control strategy in coordination with a resonant branch setup is proposed to inject the detection signals. Then, the parameters of the resonant branch and the detection signals to be injected are obtained after careful consideration to ensure the optimal distribution characteristics of the injected signals. Finally, a protection principle based on a coordinating time interval scheme is proposed to locate and isolate the fault section according to the single terminal information. Simulation results show that the proposed method achieves excellent performance.