一起220 kV电流互感器故障原因分析

Fault analysis of 220 kV current transformer

通过变压器油色谱检测异常情况发现设备故障,对故障电流互感器进行解体检查,发现设备真空干燥、设备一次主绝缘存在多个问题。分析主绝缘干燥过程偏差、主绝缘包扎偏差、变压器油色谱异常的原因为局部绝缘受潮(介损增加)、绝缘包扎偏差(电场分布不均),造成设备运行中发生局部过热、水分解、局部放电现象,随着局部放电和过热的加剧,导致绝缘油劣化和大量气体析出。根据故障原因,提出相应的预防措施。

Through the detection of abnormal conditions of transformer oil chromatogram,the equipment fault was found,and the fault current transformer was disassembled and inspected.It was found that there were many problems in the vacuum drying of the equipment and the primary main insulation of the equipment.It is analyzed that the main insulation drying process deviation,main insulation binding deviation and transformer oil color spectrum abnormality are caused by local insulation moisture(increased dielectric loss)and insulation binding deviation(uneven electric field distribution),resulting in local overheating,water decomposition and partial discharge during equipment operation.With the intensification of partial discharge and overheating,insulation oil deterioration and a large amount of gas precipitation.Put forward corresponding preventive measures according to the fault causes.