一起35kV变压器有载调压开关故障分析

Fault Analysis of a 35kV Transformer on Load Voltage Regulating Switch

在运35 kV变压器有载调压开关故障,对故障设备进行油化验检查,吊芯检查,吊罩更换。判断故障原因为变压器运行过程中,分接开关档位的变换导致绝缘油分解产生游离碳,游离碳日积月累附着在绝缘件表面,导致绝缘件绝缘能力降低,7号条板AB相间发生放电击穿。

The 35 kV transformer on-load tapping switch fails during operation.Oil testing and inspection are carry out on the faulty equipment,the hanging core is checked,and the hanging cover is replaced.It is judged that the fault is caused by the decomposition of insulating oil and the generation of free carbon due to the change of tap changer gear during the operation of transformer.Free carbon accumulated on the surface of the insulator,resulting in the reduction of the insulation capacity of the insulator,and the discharge breakdown occurred between AB phase of No.7 strip.