Effect of the Properties of Insulating Materials on the Surface Electrostatic Discharge Under Positive Pulse Volage

The electrostatic discharge (ESD) on the surface of insulating materials seriously impairs the operation of power equipment and communication systems. The research on the properties of surface electrostatic discharge and its influencing factors is helpful to understand the relationship between insulating materials and surface discharge, which can also provide an important reference for the optimal design of insulation system. In this paper, an ESD gun was used to trigger the ESD on the insulating surface. The dust figure method was introduced to show the charge distribution on the insulating surface. The development of streamers was quantitatively characterized by the binarization method. Moreover, the influences of insulating properties, such as relative permittivity, surface resistivity and thickness, on the surface electrostatic discharge were studied. Experimental results indicate that, under the positive ESD, the dust figure on the surface of the insulating material is the plum blossom-like pattern. The type of material affects the development of the streamer. The decrease of the surface resistivity accelerates the dissipation of the surface charge. The length of the surficial streamer increases with the sample’ thickness increasing. Therefore, different properties of the insulating material, such as the relative permittivity, charge injection methods, charge adhesion effects, etc., will affect the accumulating form of the surface charge as well as the manner of surface discharge. Finally, the ESD process of the insulating surface is further changed by these properties. © 2023 Science Press. All rights reserved.