Analysis of grounding systems in soils with hemispherical layering

A theoretical model for the analysis of power system grounding systems located inside or near hemispherical soil heterogeneities is presented. Exact closed-form analytical expressions for the earth potential calculations due to current sources in different regions of this soil structure are obtained. Numerical results are presented for different grounding systems and for different types of hemispherical soil volumes. The results clearly show that these finite hemispherical soil heterogeneities have a significant influence on the performance of grounding systems. The results obtained are in agreement with well known simple case results and converge asymptotically to the uniform soil case.< >