Use of PSO to determine lightning channel‐base‐current function parameters for standard severe negative first and subsequent return stroke approximation

Abstract

In this study, particle swarm optimisation (PSO) is applied to determine the Heidler's function parameters (HFPs) for approximating the measured full lightning channel-base-current (CBC) of the severe (5% data in IEC standard 62305-1, 2010) negative first return stroke (NFS) and subsequent return stroke (NSS). The parameters in the sum of two Heidler's functions, namely I 01 , I 02 , τ 11 , τ 12 , τ 21 , τ 22 , n 1 , and n 2 , are identified using PSO as a tool. The HFPs for severe NFS and NSS are tuned to keep four parameters constant with systematic variation of one out of all prominent parameters (i.e. peak current ( I m ), maximum time rate of change of current ((d i /d t ) max ), front duration ( t FD ), stroke duration ( t SD ), and total charge ( Q )) of full CBC wave and vice versa. The corresponding data is reported, and an independent controlling of HFPs is analysed to achieve the desired full CBC wave. Also, an attempt has been made in this study to examine the interdependence between the wavefront and tail of CBC using PSO. The data thus generated and reported for severe NFS and NSS can be used to generate the suitable full CBC waveforms. This methodology will be helpful in lightning-related simulation study and research.