Comparison of the antenna model and experimental analysis of an impulse impedance of the horizontal grounding electrode

Abstract

The paper deals with the comparison of two methods for the calculation of the impulse impedance of the horizontal grounding electrode defined as a ratio of maximum values of induced voltage and current at the injection point on the electrode. The current distribution along the electrode is calculated using the antenna theory based model featuring the thin-wire approximation and corresponding Pocklington integro–differential equation in the frequency domain. The equation is solved using analytical technique. The scattered voltage is subsequently calculated from the Generalized Telegrapher's equation. On the other hand, experimental technique based on three-pole/potential drop method is implemented at the actual measurement site, and the data obtained are used for the assessment of impulse impedance of the grounding system. The results obtained via different methods agree satisfactorily, thus validating antenna model of the grounding electrode.