一起油浸倒置式电流互感器故障分析及其防范措施

为了分析某550 k V油浸倒置式电流互感器发生故障的原因,对同型号同批次设备的绝缘性能进行了试验研究,结合试验后设备的解体情况和电场仿真模拟对故障原因进行了分析,并提出了相应的防范措施。结果表明,局部电场集中引起的局部放电和过电压作用造成的绝缘劣化是本次故障发生的主要原因。为有效避免此类故障的发生,需要对油浸倒置式电流互感器的出厂质量进行严格把控,同时对在运设备的绝缘性能进行定期检测,建立相应的跟踪对比数据库,并着重关注其承受过电压情况,这样可以对油浸倒置式电流互感器的绝缘劣化程度进行表征,以确保油浸倒置式电流互感器的稳定运行。

Fault Analysis and Preventive Measures of Oil-immersed Inverted Current Transformer

In order to analyze the cause of fault of a 550 kV oil-immersed inverted current transformer,the insulation performance of the equipment with same type and batch is studied by test.The reason of the fault is analyzed by way of disassembly after the test with combination of electric field simulation and corresponding preventive measures are proposed.It is shown by the result that partial discharge due to local field concentration and insulation degradation due to overvoltage is the main reason for the fault.For avoiding effectively occurrence of such fault,the delivery quality of such current transformer shall be subject to strict quality control and,at the same time,the insulation performance of the equipment in operation shall be detected periodically,corresponding tracking comparison database shall be set up and the issue of withstanding overvoltage shall be focused on in particularly so to demonstrate the insulation degradation degree of the current transformer and assure its stable operation.