Transient lightning responses of grounding systems buried in horizontal multilayered earth with a hybrid method

•Hybrid method for lightning response from grid in multilayered earth was developed.•In the method, electrical circuit consists of a “T” typical of basic element.•The QSCIM was introduced into this model to accelerate the calculation.•The closed form of Green's function was introduced to accelerate calculation.•Formula of mutual induction and impedance was introduced to accelerate calculation.

Combined with the Fast Fourier Transform (FFT), a mathematical hybrid method for accurately computing the lightning response from grounding systems buried in multilayered earth model has been developed in this paper. In the method, electrical circuit consists of “T” typical of basic elements. To accelerate calculations of the method, quasi-static complex image method and closed form of Green's function and analytical formula for mutual induction and impedance coefficients were introduced into this method. With the inverse FFT, the method can be used for studying performances of transient lightning response from the grounding systems.