The physical and chemical processes occurring in non-metallic inorganic porous coatings during the passage of a high-voltage alternating sinusoidal current through the coated metal conductors are investigated by the method of mathematical modeling. The compositions of electrolytes and the modes of coating formation are developed, and their characteristics are determined. A wet coating case is considered. It is found out that at a high voltage in liquid-filled pores there are fast electrode reactions, reducing the number of charge carriers in the liquid and increasing the voltage drop in the oxide layer. The simulation results show a theoretical possibility of an 80% suppression of the corona discharge. In practice, when an electric current with a voltage of up to 75 kV passes through the 5.5 mm-diameter wires, the proposed coatings reduce the power losses on the corona discharge by 20% and increase the corona discharge voltage on the wires by 3 kV.