基于故障信息的高阻接地故障辨识与定位方法

Identification and location of high-resistance grounding fault based on fault records

高压输电线路发生高阻接地故障时,由于受过渡电阻的影响,线路保护动作行为较为复杂,故障测距结果往往误差过大。针对以上问题,提出了一种高阻接地故障辨识和故障定位的方法。该方法的核心思想是基于故障录波数据,计算故障区域各条线路两侧电流矢量和及跳闸线路两侧零序电流比值,然后根据序网络故障分析和差动保护原理,利用电网分布式继电保护计算系统进行故障辨识和定位。计算和现场巡线结果表明该方法受过渡电阻和负荷电流的影响很小,故障定位精度较高,可满足现场的应用要求。

Due to the existence of transition resistance, protection action behavior is complicated and the fault location results are often inaccurate when a high-resistance grounding fault occurs in HV transmission lines. To solve the above problems, a high-resistance grounding fault identification and fault location method is proposed. The core idea of this algorithm is to analyze the current vector of every line in fault zone and zero-sequence current ratio of the trip line based on the fault records. According to the sequence network fault analysis and differential protection principles, grid relay protection distributed calculation system is used to identify and locate the faults. Fault calculation and line inspection results show that the proposed method is slightly affected by transition resistance and load currents, their fault location results are accurate for high-resistance grounding fault, thus the method can meet the requirement of on-site application.