A study on the effect of UV radiations on silicone rubber insulators under polluted conditions using inclined plane tracking and erosion test

In the recent years, several cases of outages of silicone rubber insulators due to contamination and pollution has been reported and is on rise. Several additives and filler materials like BaN, ATH, ZnO etc were used in the recent past to improve the hydrophobic properties of silicone rubber insulators and thereby improving its resistance to tracking and erosion. In this paper the effect of pollution on composite insulators has been studied using the Inclined Plane Tracking and Erosion Test as per IEC 60587, while superimposing UV radiations. Pollutants used are fly ash, soot, bagasse ash and cement, to mimic the surroundings found commonly near coal mines and power generating stations. IEC 60587 however does not refer to the effects of UV radiations while performing the Inclined Plane Tracking and Erosion Test. In this study however, UV radiations have been superimposed on the specimen to study the effects of the same. During the course of study it was observed that the presence of UV radiations in fact reduced the erosion on polluted composite insulation specimen, while the tracking was found to increase. SEM and XRD analysis was also performed after the completion of test.