A review of recent developments in return-stroke models based on transmission line theory

This paper presents a review of recent developments in return-stroke models based on transmission line theory, which are also known as distributed-circuit models. The existing transmission line models are classified in three different categories, which are briefly outlined. A discussion on the applicability of conventional transmission line theory to represent the propagation of a current wave on a vertical conductor intended to represent the lightning channel is presented. Also, recent progress in the inclusion of nonlinear channel losses and corona in transmission line models of the return stroke is presented and discussed. Current and remote electromagnetic fields predicted by some of the reviewed models are illustrated. Examples of application of return-stroke models based on transmission line theory are also presented.