GIL管路温变伸缩致局部放电定位与成因分析  

Location and Cause Analysis of Partial Discharge due to Temperature Variation induced Expansion and Contraction of GIL Pipeline

作　　者：马荣亮 杨树锋[1] 翁利听 MA Rongliang;YANG Shufeng;WENG Liting(Xiluodu Hydropower Plant,China Yangtze Power Co.,Ltd.,Zhaotong 657300,China)

机构地区：[1]中国长江电力股份有限公司溪洛渡电厂,云南昭通657300

出　　处：《水电与新能源》2023年第1期44-47,共4页Hydropower and New Energy

摘　　要：针对某500 kV GIL设备局部放电异常信号情况,经特高频时差定位法对信号源进行定位和检测,确认其产生的原因为支柱绝缘子尾端金属触针与GIL管路外壳接触不良而发生气隙放电;原因是随着GIL管路运行时的温度变化引起伸缩滑动及导体受到电动力等因素影响,造成金属顶针弹簧失效所致。为此提出了取消绝缘子尾端的GIL管路外壳、采用低摩擦系数的材质与形状的金属触针,将螺旋弹簧调整为片式弹簧等,使问题得到了有效解决。In a 500 kV GIL equipment,abnormal partial discharge signal is observed.The ultra-high frequency time-of-arrival location method is adopted to locate and detect the partial discharge source.It is determined that the fault is the air gap discharge caused by imperfect contact between the metal pin at the end of the post insulator and the GIL pipe shell.Analysis also shows that the imperfect contact is due to the failure of the metal thimble spring,as temperature variation of the GIL pipeline during its operation causes expansion and contraction sliding and the conductor is subjected to electrodynamic forces.Thus,treatment measures are proposed correspondingly,such as removing the GIL pipe shell at the end of the insulator,adopting metal contact pin of low friction materials and shape,and adjusting the coil spring to disc spring.With these measures,the problem is successfully solved.

关 键 词：GIL 热致伸缩 接地不良 局部放电 

分 类 号：TM72[电气工程—电力系统及自动化]