抛光方式对交流电压下盆式绝缘子表面电荷分布和沿面闪络特性的影响  

Influence of Polishing Treatments on Surface Charge Distribution and Flashover Characteristics of Basin Spacer Under AC Voltage

作　　者：李进 王禹淮 张黎明[2] 王亚祥 郝留成 杜伯学 LI Jin;WANG Yuhuai;ZHANG Liming;WANG Yaxiang;HAO Liucheng;DU Boxue(Key Laboratory of Smart Grid of Education Ministry,School of Electrical and Information Engineering,Tianjin University,Tianjin 300072,China;State Grid Tianjin Electric Power Company,Tianjin 300010,China;Pinggao Group Co.,Ltd.,Pingdingshan 467001,China)

机构地区：[1]天津大学电气自动化与信息工程学院智能电网教育部重点实验室,天津300072 [2]国网天津市电力公司,天津300010 [3]平高集团有限公司,平顶山467001

出　　处：《高电压技术》2022年第10期4093-4101,共9页High Voltage Engineering

基　　金：国家自然科学基金(51807136);中国博士后基金面上项目(2021M692726)。

摘　　要：盆式绝缘子作为交流GIL关键部件,在运行工况下多次发生表面抛光区域随机性沿面放电现象,并伴随有金属粉尘,严重威胁GIL可靠运行。为此对环氧树脂盆式绝缘子进行了局部环向和径向抛光处理,测试了不同截断相位交流电压下表面电荷积聚特性和交流、交流预压以及预置金属粉尘下的沿面闪络电压,分析了整体抛光和表面修复对沿面绝缘性能的提升效果。研究结果表明:未抛光绝缘子和环向抛光绝缘子表面积聚的电荷均以负极性为主,且环向抛光后存在电荷集中带,整体电荷密度远高于未抛光绝缘子,径向抛光绝缘子的处理区域积聚的电荷以正极性为主,表面电荷整体分布极不均匀;径向抛光盆式绝缘子的闪络电压下降最为明显,预置粉尘工况下沿面闪络电压下降约为20%。抛光处理前后表面形貌和元素变化以及纯环氧树脂绝缘子的表面电荷分布结果验证了抛光区域暴露的氧化铝颗粒容易产生微放电,是表面异极性电荷积聚以及金属粉尘吸附下沿面闪络电压大幅下降的主要原因;整体抛光和表面修复后表面电荷积聚减少且闪络电压显著提升,相关结果也为GIL盆式绝缘子表面处理提供了参考和依据。As a key component of AC GIL,basin spacers have experienced repeatedly random surface discharge along the surface polishing area under operating conditions,accompanied by metal dust,which seriously threatens the reliable operation of GIL.In this paper,epoxy basin spacers were treated with partial circumferential and radial polishing.The surface charge accumulation characteristics were tested under AC voltage with different truncated phases.The surface flashover voltages under AC,AC pre-voltage and presetting metal dust were compared.The effects of overall polishing and surface repairing on the insulation performance were analyzed.The results show that the surface charge on both untreated and circumferentially polished spacers is mainly negative,the latter of which presents concentration zone with much higher charge density.While the charge on the spacers with radial polishing is mainly positive and extremely uneven.The radially polished spacer shows the biggest decrease in the flashover voltage and the decline under presetting dust condition is about 20%.The changes of surface morphology and elements of basin spacer and the surface charge of pure epoxy spacer before and after polishing verify that the exposed alumina particles in the polished area are prone to generate micro-discharge,which is the main reason for the accumulation of heteropolar charges and the decrease in the flashover voltage with metal dust absorption.After overall polishing and surface repair,the surface charge accumulation is reduced and the flashover voltage is significantly increased,which provides reference to the treatment of GIL spacers.

关 键 词：气体绝缘输电管道 盆式绝缘子 抛光方式 表面电荷 沿面闪络 

分 类 号：TM216[一般工业技术—材料科学与工程]