摘要
线夹作为导线连接的重要部件,在电力系统架空线路中被广泛使用,因导线断股、螺栓松动接触不良等导致的线夹过热现象时有发生。本文对一起变电站500kV主变变高开关上方引下线线夹异常发热的紧急缺陷案例进行分析,开展直流电阻试验、大电流温升试验、滑移试验、单线拉断力试验及解体检查,最终确定线夹过热原因为固定螺栓在投运时的紧固力矩不满足标准要求,垫片配置数量不统一,长期运行过程中导线受力导致线夹螺栓松动,致使线夹端部更易受潮腐蚀并进一步加剧接触不良,从而导致接触电阻增大,以及滑移试验与拉断力试验不符合要求。最后,提出对该批次导线加强红外监测的针对性运维策略。
As an important part of the wire connection,the clamp is widely used in the overhead lines of the power system.Due to the broken strand of the wire and the loose contact of the bolt,the overheating of the clamp occurs from time to time.In this paper,an emergency defect case of abnormal heating of the down-lead clamp above the high voltage side disconnector of 500kV main transformer in substation is analyzed.The DC resistance test,high current temperature rise test,slip test,single line tensile force test and disassembly inspection are carried out.The reason of overheating is that the fastening torque of the fixed bolt does not meet the standard when it is put into operation,and the number of gaskets is not uniform.During the long-term operation,the wire force causes the clamp bolt to loosen,which makes the end of the clamp more prone to wet corrosion and further aggravates the poor contact,resulting in an increase in contact resistance,and the slip test and the tensile force test do not meet the requirements.At last,a targeted operation and maintenance strategy for strengthening infrared monitoring of this batch of wire is proposed.
作者
王江波
周鸿铃
李光茂
乔胜亚
杨森
WANG Jiangbo;ZHOU Honging;LI Guangmao;QIAO Shengya;YANG Sen(Shenzhen Power Supply Bureau,Shenzhen 518001;Guangzhou Power Supply Bureau,Guangzhou 510410)
出处
《电气技术》
2024年第3期68-73,共6页
Electrical Engineering
关键词
线夹过热
导线断股
解体检查
clamp overheating
wire strand break
disassembly inspection
