Fault Location Method for Low Resistance Grounding Distribution Network Based on Cosine Similarity of Zero-Sequence Current

Abstract

When a single-phase grounding fault occurs in the distribution network, the zero-sequence current flowing through the two detection points upstream or downstream of the fault point is a through current with high similarity, while the two detection points located on both sides of the fault point are obviously different. In this paper, cosine similarity algorithm is used to describe the similarity of zero-sequence current between detection points. FTUs are installed at the detection points to collect three-phase current and upload it to the master station to synthesize zero-sequence current. The master station determines the fault section by comparing the cosine similarity of zero-sequence current between FTUs. At the same time, this method is not affected by fault location, fault initial phase angle and noise interference, and the above method still has strong adaptability in the case of multi branch lines and high fault resistance. Through theoretical and simulation analysis, the feasibility of the above method is proved.