A Method of Locating and Isolation for Single Phase Grounding Fault Section of Feeders in Power Distribution Network based on Time Limit Zero-Sequence Voltage

摘要

In order to solve the problem of single phase grounding fault locating in non-effectively grounding network, this paper analyzes the character of single phase grounding fault. According to the working principle of generating line insulation supervisory devices in transformer substation, the property of line imbalance voltage, and the practical operation demand of feeder terminal unit (FTU), a method of single phase grounding fault locating for FTU, the time limit & zero-sequence voltage method, is proposed, which operates on the feeder automation system of voltage-time type. The main principle about this method is given and the operating mode how to cooperate FTU is also discussed. At last, combined with the project example of Zhongshan loop-feeder automation system, the analysis about fault insulating process is described in detail. It is pointed out that the time limit & zero-sequence voltage method is feasible and practical.