Line Selection Method for Same-Phase Two-Point Grounding Faults in Small Current Grounding System

In view of the difficulty in line selection of same-phase two-point grounding fault in small current grounding system, a new method of line selection based on Euclidian distance measurement algorithm was proposed. This paper established the equivalent simplified zero-sequence network of same-phase two-point grounding fault, analyzed the transfer of zero sequence current in the system after the single-point grounding fault develops into a two-point grounding fault, and putted forward a new method of fault line selection for same-phase two-point grounding fault based on the characteristics of zero-sequence current redistribution after different lines are grounded. Finally, simulation test results verified the reliability and accuracy of the proposed line selection method, which is of great significance to the safety of distribution network and the reliability of power supply.