Development Of New Anti-Pollution Flashover Coatings

The pollution flashover is a common power safety accident, seriously affecting electric power production safety and people’s life. Coating anti-pollution flashover coatings on the surface of insulators is the most effective measures now. However, with the increase of air-pollution and the haze, the hydrophobicity, mechanical properties and service life of anti-pollution flashover coatings, can’t meet the needs. The country need to stop the high tension transmission line regularly every year, costing a large amount of manpower to clean, paint and maintain, etc., that’s very expensive. Therefore, creating a new kind of coatings with better hydrophobicity, can improve the effect, increase the service life of the coatings, extend the period of coating checking, reduce the cost of regularly cleaning greatly, besides, it can also reduce the huge economic losses because of power off operation causing by coatings’failure, fundamentally guarantee the security of transmission line, with important social and economic benefits.In this paper, first of all, the use condition of anti-pollution flashover coatings in the line was investigated, to observe the differences of insulator strings with coatings and without coatings, besides, the pollution was collected and analyzed. The RTV anti-pollution flashover coatings on the ceramic insulators used for 2 years were observed, and the hydrophobic test had operated, to prove that the property of the coatings need to be improved.To investigate the reason why the hydrophobicity of present commonly used RTV coatings and PRTV coatings is different, the substrate material and ingredients were analyzed, expositing the effect of the content of nanoparticles such as Al, Si, Ti on the hydrophobicity of coatings. And their surface morphology were observed, finding the influence law of nanoparticles’dispersion degree on the hydrophobicity of coatings.The process of adding surfactant to modify the nano-fillers in order to decrease the surface energy was improved, and the influence of surface treatment degree on the hydrophobicity was searched. The surfactant and surface treatment process when micron grade CaCO3 particles and nanoscale SiO particles were used together were explored, getting the optimal preparation process step by step. The orthogonal experiments were operated on the silicone rubber anti-pollution flashover coatings to investigate the influence of quality percentage gradient of silicone rubber, SiO2, Al2O3, TiO2 on the contact angle as well as hydrophobicity. The component formula with the best hydrophobicity was determined through the experiment results, and the hydrophobicity difference were analyzed by comparing with the RTV coatings.The effects of introducing fluorosilicone resin to silicone rubber as matrix material were observed. The adding process and other composition suitable for fluorosilicone coatings such as coupling agent, defoaming agent, catalyst and curing agent, were explored, laying the foundations of determining the optimal formula. The orthogonal experiments were operated to investigate the influence of quality percentage gradient of fluorosilicone resin, SiO2, Al2O3, TiO2 on the contact angle as well as hydrophobicity. The component formula with the best hydrophobicity was determined through the experiment results, and the hydrophobicity difference were analyzed by comparing with the RTV coatings. Tests on the appearance, surface drying time, insulation property such as volume resistivity and dielectric strength of silicone rubber anti-pollution flashover coatings and fluorosilicone resin anti-pollution flashover coatings, were operated, showing that the properties of developed anti-pollution flashover coatings exceeded the requirements of relevant national standard.