A New Analytical Equation for the Linear Resistance of Discharge During Flashover of Polluted Insulators Under AC or DC Voltages

Abstract

This paper presents a new equation for the linear resistance of discharge channel during the flashover of polluted insulators basing on an electro-energetic balance and by using some mathematical formulations. This equation shows the dependency on the applied voltage, the temperature, thermal conductivity and length of the discharge channel, the resistance and capacitance of pollution layer; the radius of discharge channel is assumed to be variable. It is valid during the whole discharge process (i.e.; during the different steps of the discharge development) in AC and DC voltages and in both static and dynamic regimes. The proposed equation has the particularity to be an analytical equation, in opposition with the main equations used till today to determine the linear resistance of discharge propagating over polluted insulators up to flashover and which are empirical equations.