Impulse impedance of rectangular grounding grids

Comparison between utility sub-station and imitative earthing systems when subjected under lightning response

“…On the other hand, some studies [14][15][16] found that the impulse impedance values were higher than the power frequency impedance. Gupta and Thapar [15] and Gupta and Singh [16] however used scaled model in a tank filled with an electrolyte in the laboratory to simulate for this analysis.…”

“…Gupta and Thapar [15] and Gupta and Singh [16] however used scaled model in a tank filled with an electrolyte in the laboratory to simulate for this analysis. They also found that the voltage and current traces have the same rise and decay times.…”

“…A number of publications [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] investigated the earthing system performance by experimental or computational methods. However, some authors [5][6][7][8] allow for non-linear behaviour and the others [1][2][3][4][9][10][11][12][13][14][15][16] did not incorporate the effect of non-linear behaviour into their investigations.…”

Transient Grounding Impedance of Electrode Elements for Grounding Mat

“…because most of the faults are due to lightning surge. As grounding electrodes are effective to the lightning protection technology in widely areas, there are many research works regarding the relations between commercial frequency resistance and the resulting soil resistivity [2][3]. Experimental and theoretical procedures for estimating the resistance have been developed for regular soil resistivity in direct current or low commercial frequencies besides complicated layers.…”

“…However, if the soil resistivity is low, impedance sometimes increases [2][3][4][5]. This is because the surge impedances of the electrode conductors come into the grounding impedance.…”