Fast evaluation of lightning‐induced voltages of overhead line and buried cable considering the lossy ground

Abstract

In this study, an efficient method for the evaluation of lightning‐induced voltages on a single‐conductor overhead line and a single‐core buried cable is proposed. In this method, the numerical evaluation of the temporal convolution due to the lossy ground is simplified by a full consideration of the inherent relation between the frequency‐dependent ground impedance per‐unit‐length (p.u.l.) and admittance p.u.l., based on which, the evaluation of the lightning‐induced voltages on an overhead line or buried cable system can be implemented in an efficient way. To further improve the efficiency, the frequency‐domain method of evaluation of the lightning horizontal electric fields above or below the ground surface is modified by dividing the lightning channel base current into high‐frequency and low‐frequency components. Some numerical examples are conducted under MATLAB platform to validate the proposed method and the efficiency is discussed.