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第 45 卷 第 2 期
电力与能源
182 2024 年 4 月
DOI:10.11973/dlyny202402009
基于甚低频地电流的线路单相接地故障
快速定位技术
牟学军,张雪强,何 冰,陈星宇,周 浩
(国网浙江义乌市供电有限公司,浙江 义乌 322000)
摘 要:低压配网系统接地故障点的查找一直是影响配网稳定运行的难题。由于故障接地位置难以快速定
位,往往会导致抢修延误、频繁送电失败等问题,严重影响了系统的安全性和可靠性。通过对单相接地故障的
研究,提出了一种基于甚低频地电流的接地故障快速查找技术,该技术具备检测精度高、不受电缆电容效应干
扰、不受同塔高电压线路电场干扰、可验证线路绝缘水平、双重化防误操作保护等优点,通过在故障处施加可
控的安全甚低频信号,利用无线数字绝缘甚低频钳表检测信号电流,即可快速定位故障点。
关键词:低压配网;甚低频地电流;线路单相接地故障;快速定位
作者简介:牟学军(1988—),男,工程师,从事配网运行工作。
中图分类号:TM862 文献标志码:A 文章编号:2095-1256(2024)02-0182-04
Fast Location Technology of Single Phase Grounding Fault of the Line Based on
Very Low Frequency Ground Current
MOU Xuejun,ZHANG Xueqiang,HE Bing,CHEN Xingyu,ZHOU Hao
(State Grid Zhejiang Yiwu Power Supply Co.,Ltd.,Yiwu 322000,Zhejiang Province,China)
Abstract:Finding the ground fault point of low-voltage distribution network has always been a trouble for the op⁃
eration of distribution network. Failure to locate the ground fault quickly leads to many problems such as delay of
emergency repair and frequent power transmission failure,which reduces the reliability of safe operation of the
system. Based on the research of single-phase grounding fault,a fast grounding search technology based on very
low frequency(VLF)ground current is proposed. This technology has the characteristics of high detection accu⁃
racy,no interference from cable capacitance effect and from electric field of high-voltage line in the same tower,
verifiable line insulation level,dual protection against misoperation,etc. By applying the controllable safety VLF
signal at the fault,the signal current is detected by the wireless digital insulation VLF clamp meter,and the fault
point is quickly located.
Key words:low-voltage distribution network,very low frequcenay ground current,single-phase grounding fault
of the line,fast location
10~35 kV 电力系统单相接地故障点的查找 示,对于电缆出线分支较多或距离较长的线路仍
一直是困扰配电网运行的难题 [1-2] 。在义乌地区 有限制。智能柱上断路器可以加快故障查找的速
配网中,由于负荷大、地形复杂、小型工业园区众 度,但由于无法密集安装,仍然存在定位故障点耗
多、终端用户设备复杂等特点,常常出现线路接地 时较长的问题 。
[3]
故障无法及时定位的问题,给修复工作带来了困 本文针对单相接地故障查找开发了基于甚低
扰。现有故障查找技术存在查找困难、查找效率 频地电流的快速定位技术。该技术利用最新的接
和查找精度低等问题,限制了其在义乌地区的应 地定位检测方案,使用模拟甚低频摇表的高压小
用。故障指示器也只能在有限范围内提供接地指 电流甚低频电流信号源,在故障线路段的接地环