Effect of profile location on step and touch voltages of grounding grids

A Boundary Element Approach is used to get the numerical computation of grounding system analysis such as the equivalent resistance and the distribution of potential on the earth surface due to fault currents. The results in this paper are produced by the techniques that have been implemented in a computer aided design (CAD) system for grounding grids of electrical substations. The paper investigates the effect of profile location on some parameters such as the value of the grid resistance, step and touch voltages, and also presents some cases of grid configurations with and without vertical rods to explain the variations of these parameters with the variations of profile location.

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