Safety analysis of grounding grid for substations with different structure

The influences of the grounding conductor number for a ground system in different designs on the touch and step voltages on the earth´s surface are analyzed in detail in this paper. The result of this study can be used to determine the rational number of grounding conductors, which can equalize the leakage current distribution and markedly decrease touch voltage and step voltage on the earth´s surface. Therefore, the designers can design the grounding system for substations and power plants safely and economically. The same analysis is also performed on the unequally spaced grounding grid where the grid conductor spacing increases progressively from the periphery to the center instead of an equally spaced grounding grid