Analysis of Leakage Current of 220kV Long Rod Insulators at Different Severity Level of Salt Contamination

Insulator is one of the most vital elements of Power transmission system at high voltage. The performance of high voltage insulator is strongly affected by environmental pollution in coastal regions. Long Rod insulator is widely used for good performance in pollution regions. In this paper Long Rod insulator is examined in different Salt contamination level. With long term use of insulators in salt areas like near coastal areas salt particles is accumulated on high voltage insulator with help of wind, humidity, fog and moisture. These particles form a conductive layer on insulator surface and provide an ideal path to flow leakage current from line conductor to ground through insulator. The performance of polluted insulator mainly depends on the conductivity of the polluted surface layer or on the equivalent salt deposition density (ESDD). In this paper Leakage current is evaluated at different ESDD level of salt pollution on 220kV Long Rod insulator. The performance of COMPOSITE and PORCELAIN Long Rod insulator is examined at different pollution level.