Modelling of DC arc discharge on ice surfaces

Using a triangular ice sample, the characteristics of the DC arc appearing on ice surfaces was investigated. Based on the results obtained, a model for predicting the 50% flashover voltage of ice-covered insulators energised with DC was presented. The model takes into account the ice surface conductivity, voltage polarity and arc root radius. Moreover, to validate the model, the 50% flashover voltage of a short string of five IEEE standard insulators covered with artificial ice under both DC- and DC+ was measured. There was an excellent concordance between the experimental results and those calculated from the mathematical model