一起500kV变压器故障原因分析

Analysis of reasons of 500 kV transformer fault

天荒坪抽水蓄能电站配套工程中某台 5 0 0 k V变压器安装后现场验收时 ,因 B相局放试验未通过而返厂解体检修 ,叙述了故障过程、试验结果以及原因分析。工厂在实体变压器上进行的过电压耐受验证试验的结果表明 ,导致变压器故障的主要原因是变压器设计时所考虑的绝缘余度太小 ,稍有意外诱发因素 (如小气泡或过电压 ) ,就会造成不可挽回的绝缘损坏。为此 ,在订购壳式变压器时 ,要注意变压器的绝缘余度 ,并对新变压器提出了

A 500 kV transformer of the matching project of Tianhuangping Pumped Storage Electric Power Station was not accepted in the site acceptance tests because it failed the test of B phase partial discharge and was returned to factory to find the fault reason. The result of tests in the factory showed that the main reason was that the redundancy which was determined in the designing stage of the transformer was too small and numerous damage would be easily made with least induced factors such as little bubbles or overvoltage. So the transformer redundancy should be paid attention while ordering a shell transformer. Requirements for new transformer were all put forward.