Factors affecting the leakage current bursts of high voltage polluted insulators

This paper presents experimental study to simulate the natural pollution conditions of high voltage polluted insulators. The effects of some factors on the leakage current bursts (number and magnitudes) are studied. Among these factors are the effect of polluted layer conductivity on the leakage current bursts, the effect of wetting method of polluted layer of high voltage insulators on the leakage current bursts, effect of the method of applying the high voltage on leakage current bursts and effect of pollution layer material on the leakage current bursts. In these tests the investigated insulators are covered with a homogenous layer according to IEC. The degree of severity is evaluated by surface layer conductivity. The paper contains also high voltage tests to simulate the desert conditions in which the dew is usually formed when the air temperature drops sharply while the humidity is high.