Comparative Analysis of Grounding Grid Configurations with Equal and Unequal Spaced Design

Abstract

This study presents the comparative analysis of three grounding grid configurations to find the optimum grid design in terms of safety parameters. Square grid, rectangular grid and L-shape grid, buried in two-layer soil model are taken in this study. Same grounding area is considered to design three different configurations of grounding grid. Effect of different grid designs, shapes and dimensions on grounding system performance is noticed. Equal and unequal spaced grounding grids for each shape are designed and it is found that unequally spaced rectangular grid gives better results than other considered designs. Study shows that rectangular grid has minimum value of grounding system resistance, grounding potential rise and mesh voltage in comparison of square and L-shape grid. ANSI/IEEE standard 80–2000 are used to designing the grids and all safety constraints are followed as mentioned in the slandered. Good agreements are found with unequal spaced rectangular grounding grid in comparison of square and L-shape grid. Two-layer soil structure is considered in the analysis. Vertical rods are placed at the periphery of the grid.