Study on surface electric field of converter station post insulators under contaminated conditions

To investigate the pollution deposition characteristics of post insulators in converter stations, this study took insulators from GZ Converter Station as the research subject. Experimental analysis was conducted to identify the composition of contaminants on the insulator surface, while a model of DC insulators under contaminated conditions was constructed using COMSOL software. The experimental results reveal that the surface contaminants of insulators are of diverse compositions, and insulators exhibit selective adsorption of atmospheric particles. Simulation results show that, for dry contaminants, their impact on the surface electric field of insulators increases in the order: Na2O < CaO < MgSO4 < NaCl < SiO2. For wet contaminants, their impact decreases in the order: Na(OH)2 > MgSO4 > CaSO4 > Ca(OH)2 > NaCl. Furthermore, the presence or absence of hydrophobicity of insulators has little effect on the surface electric field.