电容式电压互感器介损试验仿真与验证

Simulation and Verification of Dielectric Loss Test of Capacitor Voltage Transformer

对电容式电压互感器(CVT)介损测试方法进行研究,为CVT整体介损现场测量与结果分析提供理论依据。对CVT介损测试方法进行理论分析,并建立了仿真模型。通过改变仿真模型中各个电路参数值,并进行多次仿真计算,得出各个参数的变化对CVT整体介损的影响。通过现场试验验证得到:试验时短接中间变压器二次绕组,可以避免测试结果出现负介损,但结果与真实值仍然有差别;中间变压器一次绕组末端对地绝缘电阻越大,则测量结果越接近真实值。

The dielectric loss test method of capacitor voltage transformer （CVT） is studied to provide theory basis for the overall dielectric loss field test and result analysis of CVT. The CVT dielectric loss test method is analyzed theoretically, and the simulation model is built.By changing parameters of each circuit in the simulation model and multiple simulation calculations, the influence of the change of each parameter to the overall dielectric loss of CVT is obtained. It is verified by field tests that the negative dielectric loss can be avoided in the test results by the shortcircuit of the secondary winding of intermediate transformer during the test, but there are still different between the result and the real value. The larger the insulation resistance to ground of the primary winding of intermediate transformer, the more the measurement result is close to the real value.