湖南电网架空线路复合绝缘子掉线分析及建议

Analysis and Suggestions on String Breakage Failure of Composite Insulator of Overhead Transmission Line in Hunan Power Grid

文中针对湖南电网近10年复合绝缘子掉线问题,对掉线案例进行了统计分析,发现500 kV线路掉线概率更大,7次掉线有6次本体损伤和1次设计不合理共两种类型,其中本体损伤有2次为芯棒脆断、4次为芯棒酥断。选取10支样品在实验室开展机械、电气试验,机械破坏负荷、耐漏电起痕、芯棒耐酸试验、剖检试验等均未检出同批次样品不合格情况。提出了复合绝缘子抽检试验项目优化建议,针对掉线重灾区的超高压线路复合绝缘子推荐了入网检测关键项目,同时针对复合绝缘子专项巡视提出了可操作的具体建议。

In view of string breakage problem of composite insulator in Hunan Power Grid of last 10 years in,the string breakage case is statistically analyzed,finding that the string breakage probability of 500 kV line is higher.There are two types of breakages out of the 7 times,one type is 6 times of insulator proper damage and the other type is 1 time of unreasonable design.In the former type 2 times are core brittle fracture and 4 times are core bar brittle breakage.10 pieces of samples are selected for mechanical and electrical tests in the laboratory.The same batch of samples were not found to be unqualified by mechanical damage load,anti⁃leakage tracking,acid resistance test of core bar and autopsy test and so on.The optimization suggestion of sampling test items of the composite insulator is proposed.The key items of access detection of composite insulator of EHV transmission lines in severe string breakage area is recommended and,at the time,specific operational suggestion for the special patrol inspection of composite insulator is proposed.