Extraction method of insulator discharge area in ultraviolet image and its application

The ultraviolet imaging detection is one of the important detection methods of power equipment insulation, which is of great significance for detection of the equipment insulation state, ensuring its normal and safe operation, and reduction of power system safety accidents. According to the characteristics of the ultraviolet image, the threshold method, the noise reduction algorithm based on mathematical morphology and area filtering, and the four neighborhood connection method are used to extract the discharge area in the ultraviolet image and calculate its area. The algorithm in this paper is used to deal with the partial discharge ultraviolet image of the insulator string, and the extracted discharge area agrees well with the actual, verifing the validity of the algorithm. The ultraviolet image of partial discharge of clean and polluted glass insulators under different voltage is taken, and the discharge area is calculated by the algorithm in this paper, whose result shows that the partial discharge area of polluted glass insulator is large than the clean one.