Identification and Isolation of Line Breakage Fault in Distribution Network Based on Zero Sequence Voltage Amplitude Differential Principle

The over-voltage, personnel and animal casualties, rotating motor damage and other accidents often occur in distribution network, which are caused by line breakage fault. In order to solve this problem, distribution characteristics of the zero sequence voltage are analyzed when a line breakage fault in distribution network occurs. There exists a large zero sequence voltage amplitude difference on both sides of the fault point because the system is unbalanced and the voltage is not continuous due to the longitudinal disconnection. Based on this characteristic, a fault identification method based on zero sequence voltage amplitude differential principle is proposed, and two fault processing modes of distributed mode and centralized mode based on distribution automation are given. PSCAD simulation shows that the proposed method can locate all kinds of line breakage fault and is immune to neutral point grounding mode, grounding transition resistance and load size, but it depends on communication.