Research on Line Selection Technology for Two-point Same-phase Ground Faults in Medium-voltage Distribution Networks

At present, the problematic line selection method for single phase grounding faults of the small current grounding system has been mature, but line selection method for two-point same-phase ground faults is rarely studied. For the problem that the accuracy of line selection equipment is low for two-point same-phase ground faults, a fault model is established and the fault signatures are analyzed theoretically. As the faulty line zero-sequence current is affected by more factors, it is not possible to select the line with the common line selection technology for single-phase grounding faults. By further theoretical derivation, a new method for successive judgment of faulty lines is proposed, and the correctness of problematic characteristics and the feasibility of line selection technology are verified to many different cases by simulation using the ATP simulation experimental platform.