Research on the influence of ac current overflowing on grounding electrode corrosion

In the power system, earth electrode is laid in the soil for current overflowing, to ensure secure and stable operation of power grid and electric accessory. Compared with general pipeline laid in the soil, earth electrode is under the circumstance of unbalanced grounding current of neutral point and electric field induced by high-voltage transmission line, so there is current straightly overflowing from electrode surface to the earth. Grounding current density carried by earth electrode is large, with an important effect on electrochemical corrosion of earth electrode in the soil. Based on the established corrosion model, this paper makes research on the influence of AC current overflowing on corrosion potential, current and deformation, without considering the effect of species diffusion. What is more, the relationship between the amount of corrosion deformation and the frequency of ground current is also studied. (paper)