A fast and accurate analysis of grounding resistance of a driven rodbed in a two-layer soil

A moment method of the Galerkin (variational) approach is applied to analyze the grounding resistances of driven rodbed of various configurations. Using this approach the resistance of a rodbed of N rods in two-layer soil requires only a matrix size of 2N/spl times/2N (two segments for each rod). The error in the calculated resistance is less than 4% compared to the resistance calculated by point matching moment method of large number of segmentation for each rod. The efficiency due to a small matrix with high accuracy allows an extensive parametric analysis of the rodbed. The study shows that a precise placement of the rods is not necessary to maintain a given resistance.