电容分压器中压端对地绝缘电阻对tanδ测量值的影响

Influence of Ground Insulation Resistance of Medium Terminal of Capacitive Divider on tanδ Measurement

在对电容分压器的tanδ测试中,有时会出现高压电容和中压电容的tanδ在正常的范围内,而总电容tanδ明显偏小甚至为负值的现象。针对这种异常情况,通过建立电容分压器中压端对地模型,分析确定了电容分压器中压端对地绝缘电阻对tanδ测量值的函数关系,并在实际的电容分压器产品上模拟试验,验证分析的正确性,为处理此类电容分压器tanδ异常的情况提供参考。

In the measurement of tanδtest of capacitive voltage divider,such phenomena as tanδof high voltage and medium voltage capacitors is sometimes in the normal range but total capacitance tanδis obvi-ously smaller or even negative.In view of this abnormal situation,the function relation of ground insulation resistance of medium terminal of capacitive divider to the tanδmeasurement is analyzed and determined by way of establishing ground model of medium terminal of capacitive divider.The simulation test is per-formed on the actual capacitive divider to verify and analyze its correctness,which can provide reference for the abnormal tanδof such capacitive divider.