The Influence of Natural Contamination on Pollution Flashover Voltage Waveform of Porcelain Insulators in Heavily Polluted Area

It is significant to reveal the characteristics of voltage waveform of porcelain insulator with heavy industry pollution in flashover test. In this study, the contamination of insulator samples came from heavy industry pollution areas was measured. The voltage and leakage current signals in the pollution flashover test were recorded completely. A parameter, Uw, was formed by summing the variation slope of the peaks of voltage on insulator of each power frequency cycle. It quantified the fluctuant accumulation of voltage signal waveform. Another parameter, Kfv, was formed by calculating the drop slope of voltage at flashover. It was analyzed that the effects of the pollution severity and contaminant content of insulator on fluctuant accumulation of voltage signal and the drop slope of voltage at flashover. It is found there is a positive correlation between the ratio of non-soluble to soluble deposit on insulator, RNE, and the pre-flashover voltage fluctuant accumulation, Uwb. Moreover, the very heavily polluted insulators have ultra-high value of Uwb, the medium and light polluted insulators have the outstanding value of Kfv.