Electric Field Distribution of Soluble Salt Deposition on the Surface of Insulators in Railway Overhead Lines

Abstract

Different constituents of soluble salts have different effects on the insulation performance of insulators. To study the electric field distribution of soluble salt deposition on the surface of high-speed railway insulators, a two-dimensional model of the cantilever insulator electrostatic field and constant-current field with soluble salt deposition is constructed. The simulation results indicate that the relative dielectric constant of dry pollution is the main factor that affects the electric field distribution on the surface of the insulator. The electric field intensity is arranged in the following order: CaSO 4 >KNO 3 >NaNO 3 >K 2 SO 4 >NaCl>MgSO 4 , and the conductivity of each dirty liquid in the wet state becomes a key factor affecting the electric field distribution, which is specifically shown as sodium chloride>nitrate>sulfate. The simulation results are compared with existing test results to verify that they were correct. It is also found that the electric field intensity of the insulator with good hydrophobicity is slightly greater than that of the insulator without hydrophobicity. The results provide a theoretical basis for the classification of regional pollution levels and the testing of insulator contamination in the laboratory.