Effect of UV Irradiation on the Leakage Current of Polymeric Insulators

Inhalt:
This paper reports the results of an experimental investigation on the effect of ultraviolet (UV) radiation on the leakage current of 11kV silicone rubber insulators. The UV cycles are carried out as specified by ISO 4892-2, where the number of exposure/condensation cycles is varied. Tests on dry clean and polluted wet insulators were performed with and without UV irradiation. The leakage current is acquired continuously as an indicator of the insulator surface condition.. Initial results on irradiated, polluted insulators show that UV irradiation appears to increase the leakage current of insulator surface soon after irradiation. A spectral analysis using Fast Fourier Transform (FFT) is carried out to investigate changes in the leakage current harmonics for various UV cycles.