Modelling of positive discharges in laboratory gaps under switching voltage impulses

A simplified model of leader development based on physical and engineering approximations for laboratory long gap discharges under switching impulses was proposed and tested. The model was derived from the physical analysis proposed by Bondiou-Gallimberti and the engineering approximation for the potential drop on the tip of the leader proposed by Rizk. The calculated leader development characteristics with this model were compared with experimental results and numerical models. The proposed model is in close agreement with the existing published data. The calculation method was applicable to long gaps with rise times higher than 100 ¿s.