Influence of acid rain+multistress conditions on the long term performance of 28 kV polymeric insulators

Acid rain can deteriorate high voltage outdoor insulators and affect their performance in addition to their other degrading effects. Polymeric insulators can be especially susceptible since they are mostly organic. It is of practical interest to study the long term performance of polymeric insulators under acid rain+multistress conditions, simulating an actual service environment. This paper presents the results of the research on the performance of 28 kV distribution class thermoplastic elastomeric (TPE) and silicone rubber (SiR) polymeric insulators under Mexico City, Mexico, conditions. Aging for 4 lab-years (2544 h) showed loss of hydrocarbon bonds in TPE and loss of hydroxyl and hydrocarbon bonds in SiR insulators.