Application of dynamic two-arc model to flashover of HVDC insulators subjected to cold climate regions

The main objective of this contribution is to present a dynamic two-arc model to study the behavior of DC arcs on ice-covered post insulators. This model provides an appropriate tool to determine minimum flashover voltage (VMF) which is a determining factor in the selection of insulators under icing conditions. The proposed model takes into account the environmental pollution level, insulator geometry and, most importantly, applied voltage polarities. The model is validated against laboratory data consisting of flashover tests on a typical 735-kV ice-covered post insulator under DC voltage. The experimental results have good agreement with those computed by the proposed model. This model could be regarded as an important basis for the development of multi-arc models, not to mention being a powerful tool for the design and selection of EHV insulators subjected to ice accretion.