Leakage current flow through wooden pole structures of varying age on overhead distribution system

Insulation degradation leading to leakage current flow through the high voltage insulator is a major problem faced by various power distribution utilities in Australia and many other parts of the world. The excessive leakage current flow into the wooden supporting structures (wooden cross-arm and pole) leads to pole-top fires and subsequently power supply interruptions. Most prior researchers focused on flashover phenomena of insulators rather than investigation of leakage current leading to pole fire. This paper investigates the continuous current flow path originating from the high voltage conductor to various locations through the wooden pollen structure. The results are of significance to the study of high voltage insulation whereby it extended the study of flow of leakage current into the wooden supporting structures. Experiments were conducted on three different wood samples of varying ages to detect, track and compare the leakage current through the wooden pole structure. Also the effect of moisture content on leakage current was investigated on one of the wood samples.