集中式新能源电站联络线零序阻性电流差动继电保护方法

Zero Sequence Resistive Current Differential Relay Protection Method of Tie-Line for Centralized New Energy Power Station

基于一起集中式新能源电站联络线单相接地典型故障,分析故障零序电流特性,提出小电阻接地电站联络线零序阻性电流差动继电保护方法。联络线两侧电站均为小电阻接地的方式,联络线单相接地时零序差动阻性电流分量是一个恒定量,与联络线及两侧电站对地电容量无关。该方法提升了对电站联络线单相接地故障判别的准确性、灵敏性。

Based on a typical single-phase grounding fault of tie-line in a centralized new energy power station,the zero sequence current characteristics of the fault are analyzed,and a differential relay protection method of zero sequence resistive current of tie-line in a small resistance grounding power station is proposed.The power stations on both sides of the tie line are grounded by small resistance,and the zero-sequence differential resistive current component is a constant when the tie line is grounded in single phase,which has nothing to do with the capacitance of the tie line and the power stations on both sides to the ground.This method improves the accuracy and sensitivity of judging the single-phase grounding fault of power station tie line.