Performance Evaluation of Steel Grounding Grid Considering Service Life Corrosion

Some grounding grids made of steel are corroded by soil, the cross-sectional area of grounding conductor decreases with the increase of service life. Therefore, there may be grounding corrosion risk. In order to consider the influence of service life corrosion, a performance evaluation method of corroded steel grounding grids has been proposed. Firstly, the eight-index method has been used to evaluate the average annual corrosion rate of soil. Secondly, the accelerated corrosion effect of AC stray current on operating grounding grids has been analyzed. Finally, the residual cross-sectional area of grounding conductor has been solved according to service life, and its grounding impedance, conducting resistance, and current-carrying capacity have been checked. This paper provides an engineering means for the performance evaluation of corroded grounding grids, which can accurately analyze the remaining life of grounding grids.