Modelling of the Positive Lightning Impulse Flashover of Medium Voltage Overhead Line Insulators using ATP/EMTP

Accurate modelling of the lightning impulse flashover of medium voltage overhead line insulators is of great importance for insulation coordination studies of distribution networks. This paper presents an application of the CIGRE leader progression model implemented in ATP-EMTP to the prediction of the positive lightning impulse flashover characteristics of a typical 24-kV pin-type porcelain insulator. A reasonable agreement between simulation and experimentally obtained results on the dynamics of discharge development as well as on flashover characteristics is achieved by using appropriate parameter values in the leader progression model.