A method of obtaining of electric arc model parameters for SF6 power circuit breakers

A new method of calculating parameters of electric arc model of SF₆ power circuit breaker is proposed. The methodology consists in the optimization of a theoretical function with respect to a group of parameters of model in order to achieve a better approximation to a set of experimental data. The theoretical function is an asymptotic solution for the voltage that is obtained for a selected period of time. The developed method is applied to obtain the parameters of an arc model previously published in the literature. By means of a variation of the cooling power P₀ + P₁iu, a new electric arc model is obtained including the additional parameters of model. The new model has a very compact form and results in a better correlation between the theoretical voltage curves and the experimental oscillograms.