一起35kV主变有载调压开关故障的分析

Analysis of a 35 kV Main Transformer On-Load Voltage Regulating Switch Failure

介绍了某35 kV变电站一台35 kV主变有载调压开关在切换过程中发生桥接电阻断裂,引起内部弧光放电,造成油质劣化的事故。分析原因为变压器高压侧无保护运行,有载调压开关长时间故障引起主变本体相间短路,导致主变高压侧对侧线路后备保护动作跳闸,主变停运。最后针对此次事故,提出了相应的防范措施。

When a 35 kV main transformer load voltage regulator was switching in a 35kV substation,the bridge resistance broke,causing internal arc discharge and oil deterioration.The reason was analyzed.Because the transformer is unprotected,the long-time fault of the on load tap changer causes the phase to phase short circuit fault of the main transformer body,which leads to the tripping of the line backup protection at the high voltage side of the main transformer and the main transformer outage.Finally,corresponding preventive measures are proposed for this accident.