Electrical Equivalent Circuit Simulation of Polluted RTV Silicone Rubber Coated Insulator Under Salt Fog Condition

Leakage Current (LC) identification is commonly used to diagnose the insulator’s health, whether it is in good or bad condition. This paper reports the result of LC identification of polluted Room Temperature Vulcanized (RTV) coated ceramic insulator under salt fog condition. An electrical equivalent circuit of insulator was proposed to simulate the LC waveform. The simulation was done using ATPDraw software. The simulation result would be validated for its magnitude, waveform, Total Harmonic Distortion (THD), and dominant harmonic number. Several simulation case studies were conducted, which are applied voltage variation, salt fog conductivity variation, and prior to flashover condition. The results show that the insulator characteristics could be identified by analyzing the pattern of the obtained electrical parameters from each condition. The electrical properties are not much changed as the applied voltage increased. Meanwhile, the electrical properties of the insulator are affected by the salt fog conductivity. Insulators used on high conductivity salt fog will have lower resistance and a high tendency to initiate arc on the surface. Prior to flashover condition is warned by the decreasing of the surface resistance and high severity level of arcing.