Study of changes in leakage currents under a contaminated and moistened surface of insulators of the PS-6B, PS-120A, PSD-70E types of overhead power lines

Abstract

In the process of operation, insulators are exposed to repeated pollution and atmospheric influences. This is due to the removal of pollutants from industrial metallurgical enterprises, chemical plants and their deposition on the surface of insulators near power transmission lines. In normal operation, when the insulators are dirty, but their surface is not wetted, the active component of the total leakage current can be neglected. It is another matter when the surface of the contaminated insulator is intensively moistened by atmospheric influences, for example: rain, fog, dew, respectively, and the value of the active component of the leakage current also increases in proportion to the conductivity of the formed electrolyte, the layer of contamination on the surface of the insulating surface of the insulator. The article discusses the method of measuring leakage currents on the contaminated surface of various types of glass plate insulators in laboratory conditions, with artificial and natural contamination. In the dry state, a leakage current flows through contaminated insulators, which mainly depends on the electrical capacity of the insulator. A method of calculating the active component of the leakage current is proposed, since the active component of the leakage current is the main parameter for determining energy losses due to its dissipation into the environment. The results of the change in the value of the leakage currents in the time characteristics after wetting the surface layer of pollution to the leakage current in the dry state of the insulator surface are given. The observation of drying processes of a contaminated and moistened surface due to the influence of leakage currents is given. The formation of dried zones on the surface of contaminated insulation of plate insulators of overhead power lines under the action of leakage currents was investigated. An analysis of the obtained results was carried out, conclusions were drawn.