Influence of sugar as contaminant on outdoor insulation characteristics of RTV coating insulators

This paper describes the influence of sugar in contaminant to outdoor insulation characteristics of RTV coating insulator. First of all, field tests were carried out to analyze the pollution layer condition of field discharge insulators. Then RTV coating was selected to eliminate the pollution discharge, and the differences of surface condition, surface resistance and flashover voltage of RTV coating insulators between the contaminants with and without sugar were investigated in the lab. Finally, the differences of hydrophobicity transference between the RTV coating plate glass sample covered with the sugary contaminant and that covered with non-sugary contaminant were also investigated in the lab. The research results show that the sugary contamination is very absorbent and viscous, the hydrophobicity transference and the flashover voltage of RTV coating glass insulator covered with sugary contamination are worse than that covered with non-sugary contamination, but the flashover voltage is still higher 25% than that of non-RTV coating glass insulator. So it is still effective to improve outdoor insulation characteristics of glass insulator by spraying RTV coating in the sugary contamination areas.