Frequency of occurrence of lightning overvoltages on distribution lines

The evaluation of lightning overvoltages on distribution lines has been a subject of intense studies and research in recent years, covering evaluation methodology, field observation of induced voltages and direct strokes, theory of voltage induction on lines, experiments with scale models, effectiveness of protection means such as installation of shield cable or arresters along the line and others. This paper presents a review of the evaluation methodology and discussion of some aspects related to the subject, including comparisons of the quantification of frequency of overvoltages with calculations performed with the striking distance according to the electrogeometrical model and Eriksson´s model, and verification of the influence of considering the wave front time of lightning currents on induced voltages estimated by Rusck´s theory.