Influence of surge arresters on the statistical evaluation of lightning performance of distribution lines

The statistical assessment of the lightning-performances of distribution lines must take into account the presence of protection devices such as surge arresters and shielding wire/neutral groundings. Indeed, the presence of those devices does modify the indirect lightning-response of the line. A statistical investigation based on the Monte Carlo method is carried out on a distribution line with realistic configuration, aimed at assessing the indirect lightning-performance of the line. Accurate models are used to evaluate the lightning performance of the line equipped with surge arresters, in order to estimate the effects of arresters spacing and characteristics. A preprocessing procedure based on the simplified Rusck formula for a first evaluation of the lightning-induced voltages of the randomly generated events is implemented in order to reduce the computational time.