Study on the relationship between the characteristics of water droplets on the shed of composite insulators and the pollution flashover voltage

The anti-pollution flashover characteristic of composite insulators is the main indicators to evaluate their electrical performance, and the pollution flashover voltage can directly characterize the anti-pollution flashover characteristics of the insulators. This paper proposed an on-line detection method for the pollution flashover voltage of composite insulators. Samples of composite insulator shed with different hydrophobicity were prepared by using NaOH solution with pH value of 13 and temperature of 80 °C. According to the distribution of water droplets on the surface of the sample, the characteristic parameter of the number of water droplets was proposed. The samples with different characteristic parameters were smear-stained and used for the pollution flashover voltage test. The relationships between the number of water droplets on the sample surface and the pollution flashover voltage and leakage current were obtained, which can provide guidance for the evaluation of the operation state of composite insulators.