Transfer of Hydrophobicity of Polymeric Insulators for Various Pollution Severities

Abstract

Polymeric insulators exhibit good performance under polluted conditions due to the unique property of hydrophobicity. However, the flashover of insulators occurs due to the development of leakage current under severe contamination. The initially hydrophobic surface of the insulator is lost when exposed to electric discharges or pollution. It is, therefore, necessary to understand the performance of insulators for different pollution severities when placed in actual service environment. The surface of the polymer insulator gets deteriorated as it ages but during the initial period of aging it is said that hydrophobicity exists even under polluted condition. This phenomenon is called hydrophobicity transfer. In this aspect, this work is carried out on polluted polymer insulators to understand whether hydrophobicity transfer occurs for various pollution severities. The experimental investigation was carried out to understand whether hydrophobicity persists for the lower thickness (<1mm) and 1mm coating of polymeric insulators. The results of the experiments are discussed in this paper. It can be observed from the results that conductivity rises to a higher value for a thickness of 1mm coating and an increase in the conductivity is not significant for less than 1mm coating. Based on the results it can be concluded that the hydrophobicity transfer may not occur for a higher thickness of pollution.