Engineering return stroke models a review and evaluation

A return stroke model is a mathematical description that can reproduce some of the observed features of the lightning return stroke. Return stroke models help to characterize and quantify the electromagnetic fields produced by return strokes at different distances. For engineering applications, the most important parameters are the return stroke current and its generated electromagnetic fields. Therefore, return stroke models should be capable of generating electromagnetic fields and channel base currents similar to those obtained experimentally. In this paper, a review of the most commonly used engineering return stroke models is developed. A brief description of the models is presented, and using a typical channel base current waveform and return stroke speed as model inputs, the electric fields at different distances are calculated and compared with those observed in nature. In addition, by using the calculated electric fields, the main signature characteristics are evaluated and a ranking of the evaluated models is proposed.