一起220 kV油浸式电流互感器故障分析  

Fault Analysis on 220 kV Oil-immersed Current Transformer

作　　者：何清 王伟 陈元 王瑞珍 罗维 刘铁 李佳 HE Qing;WANG Wei;CHEN Yuan;WANG Reizhen;LUO Wei;LIU Tie;LI Jia(State Grid Hubei Electric Power Research Institute,Wuhan 430077,China;State Grid Hubei Electric Power Co.,Ltd.,Wuhan 430077,China;State Grid Hubei Maintenance Company,Wuhan 430077,China)

机构地区：[1]国网湖北省电力有限公司电力科学研究院,武汉430077 [2]国网湖北省电力有限公司,武汉430077 [3]国网湖北检修公司,武汉430077

出　　处：《电力电容器与无功补偿》2018年第3期111-115,共5页Power Capacitor & Reactive Power Compensation

摘　　要：本文对一起由零屏引出线绝缘损坏所导致的220 k V油浸式电流互感器内部故障进行分析。此故障表现为绝缘油中溶解气体严重超标,总烃3 668μL/L、乙炔2 227μL/L,三比值编码为102,判断认为设备内部存在电弧放电故障。设备返厂解体前,对其进行了介质损耗因数、电容量、局部放电检测,除电容量略有超标外,其他检测结果无异常。解体检查发现该台设备零屏引出线根部断裂,与之对应的一次绕组导电杆存在明显电蚀痕迹、并有炭黑沉积。经综合分析认为,此故障由零屏引出线根部绝缘损坏所致,由初始低能火花放电逐步发展为电弧放电,并在零屏断裂处形成多点接触导致环流过热,使得油中溶解气体严重超标。In this paper,the internal fault of current transformer due to insulation damage of zero-screen lead is analyzed.The fault shows the dissolving gas in the insulation oil exceeds severely the limit,with total hydrocarbon up to 3 668μL/L,acetylene up to 2 227μL/L and fault code is 102.It is thought by judgment that the low energy discharge and concurrently overheat are discharge fault are existed inside the equipment.The equipment,before being returned to the manufacture for disassembly,is subject to such test of dielectric loss factor,capacitance and PD,of which the result shows normally except the capacity is slightly exceeded.It is found after disassembly that the roof of zero-screen lead has broken and the corresponding conductive rod of primary winding has remarkable galvanic corrosion trace and carbon black deposition is existed.It is though through comprehensive analysis that the fault is due to insulation damage at the roof of zero-screen lead,developing initially from low energy spark discharge gradually to arc discharge,the multi-contact conduction at the breakage of zero-screen causes excessive heat of loop current,thus causing the dissolving gas in the oil excess severely the limit.

关 键 词：电流互感器 零屏引出线 绝缘损坏 油色谱分析(DGA) 解体检查 故障分析 措施建议 

分 类 号：TM452[电气工程—电器]