Lightning Response of Grounding Grids: Simulated and Experimental Results

Abstract

The response of grounding grids subjected to currents with typical waveforms of first and subsequent lightning return strokes is analyzed, based on experimental and simulated results. Parameters, which characterize this response, such as the grounding potential rise, impulse impedance, impulse coefficient, and effective grid area are determined for grids buried in soils of low, moderate, and high resistivity, varying the grid dimension and considering the frequency dependence of soil parameters. Based on such results, expressions to obtain the impulse impedance from the low-frequency resistance are derived.