500 kV超高压GIS开关气室特快速暂态过电压与暂态壳体地电位升高试验研究  

Experimental Study on Very Fast Transient Overvoltage and Transient Earth Voltage Rise of 500 kV EHV GIS Switch Chamber

作　　者：冯汝明 车传强 赵磊 刘涛玮 白洁 王琼 王晓东 FENG Ruming;CHE Chuanqiang;ZHAO Lei;LIU Taowei;BAI Jie;WANG Qiong;WANG Xiaodong(Inner Mongolia Power(Group)Co.,Ltd.,Inner Mongolia Power Research Institute Branch,Hohhot 010020,China;Inner Mongolia Enterprise Key Laboratory of High Voltage and Insulation Technology,Hohhot 010020,China;Inner Mongolia EHV Power Supply Company,Hohhot 010080)

机构地区：[1]内蒙古电力(集团)有限责任公司内蒙古电力科学研究院分公司,呼和浩特010020 [2]内蒙古自治区高电压与绝缘技术企业重点实验室,呼和浩特010020 [3]内蒙古超高压供电公司,呼和浩特010080

出　　处：《内蒙古电力技术》2022年第5期46-53,共8页Inner Mongolia Electric Power

基　　金：内蒙古电力(集团)有限责任公司科技项目“特快速暂态过电压(VFTO)与雷电冲击电压作用下GIS设备试验对比性研究”。

摘　　要：某500 kV GIS变电站断路器由热备用转冷备用操作时,拉开隔离开关时2号母线发生故障跳闸,根据现场故障录波图、气体检测以及对故障设备的拆解检查,借助成分分析方法以及对特快速暂态过电压(Very Fast Transient Overvoltage,VFTO)角度进行定性、定量计算,推断故障原因为设备开关触头存在设计缺陷,在操作隔离开关时存在电弧无法可靠熄灭的风险。故障暂态过程中,VFTO最大幅值达到2.183(p.u.),电弧无法熄灭,易发生对外漂移,通过行波耦合传递至壳体与地之间的壳体电压(Transient Enclosure Voltage,TEV)升高至0.47(p.u.),并且在VFTO作用下隔离开关附近存在金属异物造成电场畸变,振荡频率和电场不均匀度增加,最终导致击穿故障的发生。提出了改善隔离触头等建议,以进一步提高GIS的运行可靠性。This paper introduces the fault tripping process of No.2 bus bar when the disconnector of a 500 kV GIS substation in Inner Mongolia power grid is opened from hot standby to cold standby. Based on the field fault oscillogram,gas detection and disassembly inspection of the fault equipment, qualitative and quantitative calculations are carried out with the help of component analysis and very fast transient overvoltage(VFTO). It is concluded that the fault is caused by the design defects of the switch contacts. There is a risk that the arc cannot be extinguished reliably when operating the disconnector. In addition, during the transient process, the maximum amplitude of VFTO reaches 2.183(p.u.), the arc cannot be extinguished and is prone to drift outward. The transient earth voltage(TEV) transmitted between the shell and the ground through traveling wave coupling rises to 0.47(p.u.). Under the action of VFTO, there are metal foreign matters near the disconnector, which cause electric field distortion, increase of oscillation frequency and electric field nonuniformity, and finally lead to the occurrence of breakdown fault. Finally, some suggestions and measures are proposed to improve the isolation contact, which has a positive guidance and reference for improving the operation reliability of GIS.

关 键 词：GIS 击穿 特快速暂态过电压 成分分析 暂态壳体电压 

分 类 号：TM862[电气工程—高电压与绝缘技术]