一种耐高阻和抗负荷电流影响线路单相接地距离保护

采用集总参数建模，利用保护安装处测量到的电气量计算保护安装处到接地故障点的电压降，根据线路保护安装处到接地故障点的电压降与故障距离呈线性关系计算接地故障距离和故障线路测量阻抗。该方法原理上消除了过渡电阻和负荷电流对阻抗距离保护动作性能的影响，适用于振荡工况。仿真分析和2套不同电压等级线路的故障录波数据测试表明，所提方法具有很强的耐受过渡电阻和负荷电流影响的能力，具有良好的现场实用价值。

A single-phase ground distance protection for transmission line with strong ability of enduring fault resistance and load current

A new ground distance protection for transmission line with strong ability of enduring fault path resistance and load current is proposed. Based on the assumption that the fault path resistance is purely resistive, the voltage drop ranging from the protection location to the fault position is calculated by using the data measured by the protection. Then, fault distance and fault impedance are obtained based on the linear relation between the voltage drop and the fault distance. This paper illustrates that the new algorithm can eliminate the effect of fault resistance and load current, and is not influenced by power system swing. Simulation results and fault recorder data tests show that the new algorithm is independent of fault path resistance and load current and has good practical value.