Research on the Suppression of Nano-coatings for the Surface Charge Accumulation on the GIS Basin Insulators under AC and DC voltage

The flashover phenomenon of insulator is the main cause for the insulating failure of GIS. One of the most critical factors that impacts the surface flashover voltage is the accumulation of surface charge which can even severely restrict the performance of insulators. Therefore, it is very necessary to find a way to restrain the accumulation of surface charge on the insulators. The common methods to restrain the surface charge accumulation on the insulators were reviewed in this paper. Through the reasonable comparison and analysis for those methods, the way of nano-coatings for insulators was selected to restrain the accumulation of surface charge on the basin insulators of GIS. The raw materials and formula of nano-coating materials were developed in this paper. The effective experiments were also carried out to test the suppression of nano-coatings for the surface charge accumulation on the GIS basin insulators. The experimental results indicated that, the nano-coatings can effectively restrain the accumulation of surface charge and improve the distribution of electric field on the insulator under DC and AC voltage, the maximum degree of the suppression for the surface charge under DC voltage can reach 51.2%, while under AC voltage it is 9.3%.