MOA外表污秽对泄漏电流影响的研究

当MOA表面存在污秽时,泄漏电流及其阻性分量不仅受瓷套表面污层电阻的影响,而且还受到污层与阀片柱间耦合电容的影响。分析表明通过检测接地线泄漏电流很难真实反映MOA的运行状况;泄漏电流及其阻性分量受污层电阻的影响大于受耦合电容的影响;阻性电流的检测误差大于全电流的检测误差;污秽干区越靠近MOA下部,泄漏电流的检测误差则主要由耦合电容产生。

Research of the External Pollution Influence to the MOA Leakage Current

When external layer of MOA existing pollution, the leakage current and its resistive component are not only influenced by pollution layer resistance, but also influenced by the coupling capacitance between the pollution layer and the varistor column. Analysis indicates the leakage current cannot accurately reflect the behavior of MOA, the influence of the pollution layer resistance exceeds that of the capacitance. The detecting error of resistive component surpasses that of the leakage current. Coupling capacitance much result in the error of the leakage current if the polluted dry band is on the bottom of MOA.