Analysis of transferred Earth potentials in grounding systems: a BEM numerical approach

In this work, a numerical formulation is presented for the analysis of a common problem in electrical engineering practice, that is, the existence of transferred earth potentials in a grounding installation for metallic structures or conductors connected or not connected to the grounding grid . The transfer of potentials between the grounding area to outer points by buried conductors, such as communication or signal circuits, neutral wires, pipes, rails, or metallic fences, may produce serious safety problems. In recent years, the authors have developed a numerical technique based on the boundary element method for grounding analysis in uniform and layered soil models . First, the main highlights of this boundary element numerical approach are summarized, and next, a new methodology for the transferred potential analysis is presented. Finally, some examples by using the geometry of real grounding systems in different cases of transferred potentials are presented.