The Effectiveness of Mitigation Schemes on Electric Field Intensity (Stress Control) for Overhead Line Glass Insulator

Abstract

This paper presents the simulation results of electric field distribution within suspension insulators on different stress control techniques under dry-clean and polluted conditions. Finite element method (FEM) is adopted to estimate the electric field behaviour along the insulator profile. For this study, COMSOL Multiphysics version 5.3a is used to perform the modelling and executing the field analysis. The effectiveness of zinc-oxide (ZnO) micro-varistor and grading ring as mitigation tools for the electric field intensity enhancement was examined in this study. The reference data from the dry-clean condition was used as the benchmark to examine the effect of pollution on electric field distribution on the insulator surface. It was found that the application of the combined techniques of ZnO micro-varistor and grading ring is the best scheme for stress control as it reduced the electric field intensity up to almost 84% for both dry-clean and polluted conditions. This study also found that the positioning the grading and corona ring is crucial as it will affect the electric field intensity distribution