Advanced statistical method for evaluating of lightning performance of overhead transmission lines based on accurate modelling and considering non-vertical strokes

This paper represents a developed procedure for the evaluation of flashover rates caused by both lightning vertical and non-vertical strokes on transmission lines using a Monte Carlo method. The main goal of this paper is increase the accuracy of the flashover rates through an accurate modelling of network components such as footing impedance, transmission tower and the chain of insulators and also simulation lightning non-vertical strokes. Modelling network components, statistical parameters related to lightning and problem-solving algorithm is described. Parametric studies using this procedure can also be performed to determine the sensitivity of the flashover rate with respect to some parameters of the return stroke and the transmission line. Simulation results obtained using MATLAB and the ATP/EMTP show that considering the lightning non vertical strokes Instead of vertical strokes leads to better evaluation for lightning performance of transmission line.