Investigation of comparison on porcelain and epoxy resin insulator conditions from a coastal area due to various parameters

This paper presents the experimental results of eight months naturally coastal polluted porcelain and epoxy resin insulators. The experiments were leakage current and applied voltage measurements, in a hermetically sealed chamber, where temperature, humidity, pressure and applied voltage could be adjusted and measured simultaneously. The leakage current waveforms were analyzed using FFT and the relation to environmental parameters were analyzed using correlation matrix. It was also conducted SEM and EDAX tests. The humidity contributed to leakage current and phase angle on the porcelain insulator were 0.60 and -0.66 respectively. Whereas, on polluted epoxy resin one, the humidity did not influence to leakage current and phase angle considerably. The surface of polluted specimens became rougher than the new one. The most three chemical elements in pollutants were chlorine, silicon and ferrum.