Transient lightning response from a grounding grid buried in horizontal multilayered earth

The present study developed a mathematical model, which was combined with the Fast Fourier Transform (FFT), to facilitate the accurate computation of the transient lightning response from a grounding grid buried in horizontal multilayered earth. This approach is a hybrid of Galerkin´s method of moment and the conventional nodal analysis method. The dynamic state complex image method and the closed form of Green´s function for a dipole and monopole in the horizontal multilayered earth model were introduced into this model to accelerate the calculation of the mutual impedance and induction coefficients. Analytical formulae were developed for the mutual induction and impedance coefficients to further accelerate the calculation. With the inverse FFT, the model can be used to study the transient lightning response of a grounding grid.