一起基于在线监测与联合诊断的GIS局部放电缺陷分析

Analysis on a Partial Discharge Defect in GIS Based on On-line Monitoring and Combined Diagnosis

文中分析了一起由在线监测系统发现并通过超高频局放带电测试、超声波局放带电测试、SF_6气体成分分析、X光成像等多种先进技术手段联合诊断定位,最终由解体检查确认的气体绝缘金属封闭开关设备局部放电缺陷。经解体检查,发现220 kV 1M母线靠近天鹿线进线间隔位置的B相母线支柱绝缘子的两颗固定螺丝已有一颗脱落、另一颗松动并部分断裂,形成悬浮放电。文中通过对该缺陷从发生到诊断以及最后确认并消缺进行了详细分析,一方面说明了联合诊断与在线监测的重要作用,另一方面也为GIS绝缘缺陷诊断积累了一线生产经验。

A typical partial discharge defect in GIS was analyzed. This defect was found out by on-line monitoring, and was diagnosed and positioned by the combined technologies of UHF, AE, X-ray, etc. Disassembly inspection showed that one of the two bolts in the No.1 M bus chamber near the B-phase bus＇ support insulator has come away from its initial position, and the other has become loose with partial fracture, resulting in floating potential discharge. This paper analyzes the whole procedure of the defect from occurrence to removal for the purposes of illustrating the importance of on-line monitoring and combined diagnosis and providing experience for fault diagnosis of GIS insulation.