A method of moment to analyze the grounding grid in substation considering mutual inductance

In this paper, a method of moment to analyze the grounding grids in frequency domain is presented. The method which uses longitudinal currents of the grid segments as unknown variables considers mutual inductances and has small number of unknown variables. In order to verify the method, experiments are done on a real small grid system for testing. The calculated results obtained with the method presented in this paper are in agreement with the results obtained by the experiments. From the comparison of the grounding impedance, it can be seen that the results with the method that consider mutual inductances are better than those obtained with the method that does not consider mutual inductances.