A probabilistic model for insulator flashover under contaminated conditions

This paper presents a probabilistic model for insulator flashover based on numerical electric field calculation and random walk theory. The advancement to the state-of-the-art lies in the ability of the model to consider realistic events like arc jumping between the sheds by evaluating the electric field on the insulator surface and in the immediate vicinity of the insulator in an efficient manner. For high ESDD values (above 0.1 mg/cm2), the results from the proposed model and deterministic model are not significantly different. For ESDD values in the range 0.01-0.1 mg/cm2, which represents the majority of locations, the values obtained by the statistical model are closer to experimental results than obtained from the deterministic model. The model presented is for insulators using non-hydrophobic materials, such as porcelain, glass and several polymers.