Design and Verification of Contamination Insulator Conductivity Detecting System

Abstract

Detecting the surface conductivity of the pollution insulators has an important guiding effect on the pollution flashover warning. However, the surface contamination of insulators is uneven, and the tiny capacitance formed on the surface of insulators have a great influence on the surface conductivity detection. In order to overcome this effect, a surface conductivity detection system based on the phase angle difference was developed. The principle of the system detection and the design of the key parts of the system were introduced in detail. In order to verify the effectiveness of the system, a large number of contamination dampness tests were carried out, and the variation of contamination surface conductivity with the wetting time was analyzed. The results show that the surface conductivity is small when the contamination is dry. As dampness progresses, surface conductivity continues to increase. When the contamination is saturated damp, the surface conductivity reaches its maximum. When the contamination is supersaturated damp and loss, the surface conductivity decreases continuously. Therefore, the dampening process of contamination can be divided into three sections: damp area, saturation area and loss area. Among them, in the prevention of pollution flashover on the surface of insulators, attention should be paid to the damp area. The results show that the system can effectively detect the surface conductivity of the pollution insulator, and provide some guidance for the prevention and control of pollution flashover of insulators.