Line Selection Method of Single-phase Electric Leakage Fault for Isolated Neutral in Coal Mine

At present the coal mine power grid in China uses the isolated neutral system widely. Further, the line selection of single-phase grounding fault in this system has always been a significant study topic in the underground power system protections. In this paper, the typical line selection methods were concluded about single-phase grounding fault in small current grounding system, and the current research directions were proposed.