Study of Performance of Composite Insulators Removed from Different Contaminated Sites

Insulator pollution is the major cause of several interruptions in the electrical network. Various contaminants affect the behaviour of the composite insulators. This paper presents investigations on the performance of 25 kV composite insulatorsafter 4–5 years of field exposure. For this study insulators are collected from different contaminated areas of the south central railway lines (Indian Railways). These samples include the composite insulators exposed to contaminants of cement, marine and coal pollution. The effects of these polluted deposits on the surface of field aged composite insulators were studied. The pollution severity of these sites were observed by ESDD and NSDD methods. Electrical and mechanical tests were carried out to assess the behaviour of contaminated samples. Results of the study indicate that no major degradation observed on the contaminated samples.