Long Term Field Test of Polymer Insulator on 77kV Transmission Line

Abstract

As an anti-Vandalism measure, polymer insulator which is light and shows good performance in contamination withstand voltage is already adopted to many new power transmission lines mainly in U.S.A. However, it is said that aging deterioration is promoted by ultraviolet rays, ozone, leakage current and partial discharge because polymer insulator is made of organic materials. It is important that we seize the characteristics of aging deterioration to maintain power transmission lines. As polymer insulator for power transmission lines is more expensive than ceramic one, it is scarely used in Japan, and there is no data in the field.
In this study, we installed polymer insulator to 77kV power transmission line and carried out field test for nine years from 1997 to 2006 and investigated electrical and mechanical characteristics of them.