High frequency and transient coupling to pasive conductors near grounding systems in layered soil

This paper presents the ongoing research results of the high frequency and transient grounding system analysis in two-layer soil structure. On the basis of rigorous electromagnetic field theory, which involves Sommerfeld's integrals, the mathematical model is formulated by the mixed potential integral equation (MPIE). Detailed analysis of a high frequency performance of a typical horizontal grounding conductor placed in the upper or in the bottom layer is given. It is shown that because of the presence of two distinct layers the current distribution and the impedance to ground are highly affected by the parameters of both soil layers. Also, the current distribution in near-by passive horizontal conductor is analyzed. At the end of the paper some observations about the effects of two-layer soil structure at high frequencies are given.