主绝缘包扎工艺不良引发油浸式电流互感器内部异常产氢的原因分析

Analysis of Causes of Abnormal Hydrogen Production Inside Oil-Immersed Current Transformer Caused by Poor Main Insulation Bandage

近年来,辽宁电网发生多起油浸式电流互感器故障,故障现象为油中溶解气体中氢气、总烃含量超标,有的甚至引起互感器膨胀器顶起,严重威胁电网安全。通过对多台故障互感器进行试验和解体分析,找出故障的共性为主绝缘包扎工艺不良使油纸绝缘系统中纸绝缘存在“褶皱”,引起局部场强不均导致故障产气,并针对此问题,对设备制造商和运行单位提出建议。

In recent years,many faults of oil-immersed current transformers have occurred in Liaoning power grid.The fault phenomenon is that the content of hydrogen and total hydrocarbon in the dissolved gas in oil exceeds the standard,some even causes the transformer expander to jack up,which seriously threatens the security of power grid.Through the test and disassembly analysis of several fault transformers,it is found that the common fault is the main insulation bandage causeingthe paper insulation in oil-paper insulation system having“wrinkles”.The local uneven field strength leads to fault gas production.In view of this problem,suggestions are put forward to the equipment manufacturer and operation unit.