In this paper simplified approaches for the earth surface
potentials and GPR of substation grounding are presented
in case of uniform or non-uniform soil. The equalization of
current density and then decreasing of GPR is achieved.
The image method is suggested to calculate the GPR and
the earth surface potentials with accurate results for the
grids buried in uniform or non-uniform soil structure. The
voltage profiles have been designed in 3D to make the
selection of suitable earthing system easier. The grounding
system earth surface potential under transient condition is
investigated