±800kV直流穿墙套管回路电阻异常原因分析及处理方法  

Analysis and Treatment Method on Abnormal Circuit Resistance of ±800 kV DC Wall Bushing

作　　者：李士杰 曾少豪 李青 张新波 LI Shijie;ZENG Shaohao;LI Qing;ZHANG Xinbo(Maintenance&Test Center of EHV Power Transmission Company China Southern Power Grid,Guangzhou 510663,China)

机构地区：[1]南方电网超高压输电公司检修试验中心,广州510663

出　　处：《高压电器》2023年第3期189-194,210,共7页High Voltage Apparatus

摘　　要：针对某特高压换流站±800 kV直流穿墙套管回路电阻异常情况,结合套管内部连接结构,对该套管进行了解体分析,重点对连接部位开展了检查、成分分析及受力分析等。结果表明,该穿墙套管内部户内外段各有两处相同连接部位因受力不均引起过热,导致回路电阻出现超标等异常情况,同时发热使SF_(6)气体分解并与银、铝等金属发生反应形成污染物。文中结合解体及分析提出了更换组部件及重新镀银等处理方法,对同类型穿墙套管提出了运维建议及后续改进设计的思路。In view of the abnormal circuit resistance of ±800 kV DC wall bushing at a certain UHV converter station,the bushing is disassembled and analyzed in combination with the internal connection structure of the bushing,with inspection of the joint,component and stress analysis in particular. The results show that two identical joints in the internal and external sections of the wall bushing are overheat due to uneven stress,which leads to such abnormalities as circuit resistance exceeding the standard. At the same time,the heating causes SF_(6)gas to decompose and react with such metals as silver and aluminum to form contaminant. In this paper,such treatment methods as replacement of parts and re-silvering are proposed in combination disassembly and analysis. And suggestions for operation and maintenance of the same type of wall bushing as well as the idea of subsequent improvement design are proposed.

关 键 词：特高压直流 穿墙套管 回路电阻 解体检查 原因分析 

分 类 号：TM216.52[一般工业技术—材料科学与工程] TM721.1[电气工程—电工理论与新技术]