Study on the Typical Optical Emission Spectrograms of AC Arc Discharge over the Polluted Insulation Surface

Flashover of contaminated insulators is one of the major problems for the power distribution. Laboratory experiments have shown that the arc characteristics have great influences on the study of flashover performance of contaminated insulators. In order to investigate the characteristics of AC arc discharge on the polluted insulation surface, an experimental system was designed. The tests were carried out in the climate chamber. The optical emission spectroscopy was obtained by employing the fiber-optic spectrometer with shortest exposure time of 1 ms. The light emitted from the arc was coupled to the spectrometer by means of a focusing lens and a 3 m optical fiber. Typical optical emission spectrogram of different stages were obtained, and kinetics equation of different particles in the arc column was analyzed. And the spectrogram used for the prediction of critical flashover was proposed. It was shown that emission spectrum mainly includes sodium atom line and potassium atom line. With the increase of leakage current, the thickness of the continuous spectrum, spectral line intensity and the spectral composition increased. This work can enrich the investigation of partial arc parameters and may provide useful reference for the calculation of contamination flashover.