110kV GIS电磁式电压互感器三倍频感应耐压试验

Triple-frequency inductive voltage withstand test of electromagnetic voltage transformer for 110 kV GIS

为了发现气体绝缘的全封闭组合电器(GIS)中电磁式电压互感器(EVT)的某些绝缘缺陷,需要进行交流耐压试验。提出了110 kV GIS中EVT通过三倍频感应耐压的2种现场试验方法、试验接线及操作步骤,第1种感应耐压方案为EVT的二次绕组端子上的加压侧与补偿侧不同,第2种感应耐压方案为加压侧与补偿侧并联。通过计算,分析了试验中出现容升电压的原因及影响、空载试验的必要性及耐压时间的选定,比较了采用2种不同补偿方式的差异。现场试验结果表明EVT三倍频感应耐压时一次侧电流、二次侧电流与补偿电抗量的规律,说明第1种感应耐压方案较适用于GIS中EVT的感应耐压。

The AC voltage withstand test is applied to detect the insulation defects of EVT（Electromagnetic Voltage Transformer） in GIS.Two kinds of on-site triple-frequency test methods are presented with test wiring diagrams and test procedures.The voltage input and the compensating reactor are connected to different windings of EVT in the first method while to the same winding in the second method.The cause of capacitive voltage-augment and its influence,the necessity of no-load test and the determination of voltage withstand test duration are analyzed by calculation and compared between two methods.The results of field triple-frequency inductive voltage withstand test indicate the relationship among primary current,secondary current and compensating reactance,showing the first method is more suitable for EVT in GIS.