Application of a new dynamic numerical model to predict polluted insulator flashover voltage

This paper represents the continuation of a previous study regarding the prediction of critical flashover voltage of polluted and ice-covered insulators. An improved dynamic numerical model based on the finite element method for predicting both DC and AC critical flashover voltage of polluted porcelain and glass insulators is proposed. This model is based on the single arc Obenaus model where the arc propagation and velocity criteria are provided by the Hampton and the general Bondiou-Galimberti criteria respectively. The proposed model is implemented on the finite element method commercial software COMSOL Multiphysics™ coupled with Matlab®. In order to facilitate the finite element method simulation, the polluted insulator is modeled using the AR model. In this way, the leakage current as well as the residual resistance of the pollution layer can be easily determined using 2D simulation. The proposed model was validated using experimental and theoretical results extracted from the literature. The very good accuracy in the different results provided by the dynamic numerical model demonstrates that the use of finite element method is a powerful and versatile tool to develop an accurate dynamic numerical model in order to predict the critical flashover voltage of H.V outdoor insulators under different atmospheric conditions.