10 kV配电网单相接地故障交直流信号注入综合定位法

针对10 kV配电网单相接地故障，提出一种基于接地电阻和网络拓扑的交直流信号注入综合定位方法。该方法首先通过交流注入法估算接地电阻，对不同的接地电阻采用不同的信号注入方式和检测方式；然后结合网络拓扑和二分法原理，应用直流注入法确定宏观故障区域并进行故障点检测。综合定位方法可以有效处理接地电阻小于20 kΩ的各种单相接地故障，且不受网络结构、分布电容、线路参数和接地电阻的影响。仿真结果验证了该方法的正确性和可行性。

A Comprehensive Location Method Using AC/DC Signal Injecting for Single-Phase Earth Fault in 10 kV Distribution Network

A comprehensive AC/DC location method based on grounding resistance and network topology is proposed for the location of single-phase earth fault in 10 kV distribution network. In this method, firstly the grounding resistance is estimated by injecting AC current and different injection ways and detection modes are adopted for different grounding resistances; then combining with network topology and the principle of dichotomy, the macroscopic faulty section is determined by DC current injection and the fault point is detected. The proposed comprehensive location method can deal with various single-phase earth faults occurred in distribution network under grounding resistance less than 20kΩ effectively, and this method can hardly be affected by network structure, distributed capacitance, transmission line parameters and grounding resitance. Simulation results by EMTP and ATP verify the correctness and feasibility of the proposed location method.