Online Condition Monitoring and Leakage Current Effect Based on Local Area Environment

Abstract

High voltage outdoor insulator plays a pivotal role in safety and reliability of power transmission system.Contamination severely influences the performance of outdoor insulator. To asses contamination severity on insulator surface and to predict flashovers, leakage current monitoring is required. The amount of leakage current flowing on the surface of insulator indicates insulation safety. Increase in leakage current generates high voltage peaks at insulator dead ends. The voltage may be as high as 1000–5000 volts, mainly depends on certain weather conditions, results in enormous amount of power losses and threat to public safety. The insulator performance depends on amount and type of pollution and wetting mechanism. Leakage current is important tool to investigate insulator electrical surface activity. The scope of this paper is to review leakage current effect based on local area conditions. Leakage current importance for insulators and different techniques used to measure leakage current in lab and at field, special focus on online leakage current monitoring.