On Time-Domain Expressions for Calculating the Horizontal Electric Field From Lightning.

This paper analyzes three time-domain expressions for the surface impedance, which allows the calculation of the horizontal electric field produced by a lightning return stroke. They are the expression obtained by Barbosa and Paulino directly in the time domain, the expression obtained by Andreotti et al. as a time-domain counterpart of the Cooray–Rubinstein formula, and an approximate expression derived independently from the two former expressions. The analysis is carried out by comparing the kernels of the expressions and by comparing the lightning-induced voltages (LIVs) on an aerial line. The results show that the two former expressions provide almost identical LIVs, while the approximate one provides peak values from 5% to 7% lower than those provided by the other expressions. A detailed discussion of the results is included in the paper. [ABSTRACT FROM AUTHOR]