小浪底电厂220kV CVT介质损耗角正切值异常原因及预防措施

Abnormal Cause Analysis of 220kV CVT Dielectric Loss Angle Tangent for Xiaolangdi Hydropower Station and Its Preventive Measures

以小浪底电厂220kV开关站电容式电压互感器为例,针对2006、2007年开关站春季检修中遇到的电容式电压互感器介质损耗角正切值增大问题,以电气预防性试验数据为依据判断问题的原因及故障点,通过对设备分解检查,判断出电容式电压互感器电磁单元部分故障是设备介质损耗角正切值异常的根源,并提出了预防措施。

Taking the capacitor voltage transformer of 220 kV switch station in Xiaolangdi Hydropower Plant for an example, according to electrical preventive test data, the cause and fault point is judged to analyze dielectric loss angle tangent increasing problem found in spring maintenance of switch station in 2006 and 2007. It finds out that the electromagnetic unit fault of capacitor voltage transformer is the source of equipment dielectric loss angle tangent increasing through overhauling equipments. And the preventive measures are proposed.