Single-Phase High-Resistance Ground Fault Detection Method for Flexible Grounding Systems Based on Phase Current Discrimination

Flexible grounding system combines the advantages of petersen coil grounding and low resistance grounding, but it is unable to accurately remove the high-resistance grounding fault. In this paper, the change characteristics of phase current under different fault phases of flexible grounding system are investigated, the phase current values of different grounding methods are quantified, and according to the difference in the change characteristics of phase current between the faulted and non-faulted phases, a single-phase high-resistance grounding fault detection method based on the differentiation of phase current is proposed for the flexible grounding system. The method can accurately identify the faulted line, quickly isolate the fault, and improve the reliability and sensitivity of ground fault protection.