Performance of Over-Head Transmission Line Insulators Under Polluted Condition

High voltage insulators are essential for the reliable performance of electric power systems. All insulators are exposed to various electrical mechanical and environmental stresses. The performance of these high voltage insulators is important for both dry and wet conditions. The dissertation research topic is the investigation of electric field and voltage dis tributions(EFVD) in the surface of ceramic insulators string. Studying and understanding the EFVD of energized ceramic insulator string of high voltage 500 kV S.C.T.L used in Egypt are very important to determine the electric field stress occurring on the insulator surface particularly on the air side of the interface. The analysis is based on three conditions which are ceramic insulators string with clean surfaces with uniform contamination layer and with non-uniform contamination layer taking place over its surfaces.