سال انتشار: ۱۳۸۹
محل انتشار: بیست و پنجمین کنفرانس بین المللی برق
تعداد صفحات: ۸
E.A Cherney – Department of Electrical and Computer Engineering University of Waterloo Ontario, Canada
The paper provides an overview of the main mechanisms of aging of composite line insulators focusing on brittle fracture, dry band arcing in polluted environments, and exposure of the fibreglass rod due to handling, flashover, and wildlife. Aging is highly dependent on the service environment, type of housing material and fibreglass rod, as well as the overall design of the composite insulator. Unpredictable brittle fracture failure of the fibreglass rod which often results in the drop of an overhead conductor is one form of aging. Another form is their reduced lifetime in polluted environments that comes about due to the gradual loss of hydrophobicity of the housing material. And yet another form of aging occurs when the fiberglass rod is exposed to moisture which can come about through damage of the housing material from flashover, wildlife and handling damage, and other operational stresses. As a result, aging of composite insulators has led to the concern of increased cost of maintenance surveillance in using these insulators, particularly in polluted environments, after flashover, and after possible damage by wildlife.