Approaches to aging of composite insulators

Composite insulators, especially those based on silicone rubber, exceed the traditional ceramic or glass designs in many aspects. On the other hand, in common with other polymer insulating materials, the composite insulator suffers from inevitable deterioration and aging. Especially in seriously polluted areas, the performance of the composite insulator string may be greatly influenced by stresses such as pollution. In this paper, the problems that composite insulators face in service or manufacture are discussed. Some measures to estimate or approach the true aging state of operating composite insulators in the field are described. For the case of seriously polluted areas, the countermeasures taken to maintain the normal operation of the composite insulator are presented and discussed from the viewpoint of service maintenance.