Characterization of Hygroscopic Insulator Contamination via Laser-Induced Breakdown Spectroscopy

Flashovers seriously affect the safe operation of high-voltage transmission lines. The influence of different pollutants on the flashover of insulators differs greatly. For hygroscopic aluminum phosphate, glucose, and other contaminants, the saturated moisture and flashover characteristics can cause flashovers at low humidity. Therefore, it is of great significance to quickly detect the moisture content in the field. In this article, based on the laser-induced breakdown spectroscopy (LIBS) method, the spectral characteristics of aluminum phosphate contamination were studied, and the spectral lines that characterize the content of aluminum phosphate were obtained. The detection limit for phosphorus was calculated according to the calibration curve. The difference in the moisture content of aluminum phosphate contamination also affects the LIBS signal. The atomic spectrum of phosphorus is selected as the analytical spectral lines. Within a certain relative humidity range, spectral data normalization reduces the influence of the moisture content on the mass fraction of aluminum phosphate samples detected by LIBS. The research results are of great significance for the rapid detection of special contamination, such as aluminum phosphate, in actual lines.