Generalized stochastic model of an AC arc for analyzing the power quality

This paper describes the developed generalized stochastic model of an alternating current (AC) electric arc for analyzing the power quality. Despite the fact that the modeling of an electric arc is well studied, a number of issues still require attention. For example, there is an actual problem of accounting for the dependence of electrical parameters on the arc length. A distinctive feature of the developed model is the use of arc length data. The electric arc model is based on the generalized Cassie-Mayr equation. The probabilistic nature of electric arc burning is taken into account by means of random distortions of the equation components. The developed model was used to study the harmonic composition of the arc current of a 180-ton steelmaking furnace. The paper presents the obtained dependences of the total harmonic distortions of the current and voltage of the arc on its length. The work also shows the dependences of the harmonic coefficients of the arc current on its length.