Surface charges on silicon rubber (SiR) insulator and their effect on potential and electric field distribution

Abstract

This paper presents experimental results of the surface charges and charge decay measurement on the surface of polymeric insulator. In this research, the effect of surface charges on electric field and potential distribution has been investigated. Therefore, using measured electric charge and charge decay, the electric field and surface potential on insulator are studied by computer simulations. The accumulation of electric charge under DC electric field makes a significant difference compared to AC electric field, and this increases the rate of electrical failure and corrosion in HVDC insulators. So, a thorough understanding of the surface charge effect on insulation performance is necessary under various stresses. The experimental results revealed that the amount of charges increases linearly with the rising corona voltage and the charging time for both polarities. It was also observed that the amount of surface charges deposited by positive corona charging is less than negative corona charging. The simulation results illustrate that surface charges are important in potential and electric field variations.