A multi-arc model for predicting AC critical flashover voltage of lee-covered insulators

A multi-arc model for applications to outdoor insulators under icing conditions is developed. In order to validate the model, several insulator types and configurations, with a dry-arc distance up to 4.17 in were tested under icing conditions. The applied water conductivity of the ice was varied between 30 and 150 mu S/cm. The simulation results from the model were found to be in good agreement with the laboratory results. This model will constitute a powerful instrument for the selection of EHV and UHV insulators subjected to ice accretion.