Experimental Research on Operation Characteristics of 500 kV AC Composite Insulators in Chongqing Power Grid

Composite insulators are widely used in power system because of their remarkable pollution-resistant performance.In this paper,some 500 kV insulators with different working time and from different manufacturers are tested on their hydrophobicity,electrical character,and mechanical character,as well as the aging character of the shed material.The results show that the hydrophobicity of the composite insulators in Chongqing area decreases fast,and the electrical and mechanical characters of the composite insulators with long working time can still meet the requirement in related standard.The tensile strength,tearing strength,and electrical erosion resistance of the sheds become worse with the working time increasing.This study may benefit the operation of power grid.