Investigations on nano filled silicone rubber composites for high voltage outdoor insulation applications

Abstract

The outdoor electrical insulator is one of the important components of the power system transmission and distribution network and it directly influences the system reliability. Usually porcelain and glass insulators have been preferred for the manufacturing of insulators, bushings, cable terminations and surge arrestors for many years. In the last few decades, polymer based outdoor insulators are being increasingly used both in the transmission and distribution systems. Also they steadily capture a wider share of the market since they are offering attractive advantages such as better dielectric properties, light in weight, easy handling, resistance to vandalism, and cost effectiveness. However, there are certain disadvantages with polymeric insulators which have been found through their utilities. The most important concerns with the polymeric insulators are tracking phenomena and are aging with respect to time due to the presence of various environmental stresses like fog, humidity, temperature and rain. With the advancement in power transmission capability, it has become more important to design and develop the compact and able to withstand various environmental stresses insulating structures. Unfilled Polymers cannot perform satisfactorily under electrical and mechanical stresses and it also has poor thermal stability. Thermal stability directly influences the tracking and erosion resistance of the insulators. Without adequate tracking and erosion resistance, polymeric insulators could not perform satisfactorily under contaminated wet conditions. The electrical insulation property on the surface of the material is completely lost immediately after the tracking occurs and it never becomes recoverable. Hence universally, researchers are trying to mitigate the tracking and erosion effects in outdoor polymeric insulators with their extensive research works.