Three dimensional analysis of an AC electric arc furnace

Abstract

AC electric arc furnaces (EAFs) highly reduce power quality of the network by generating disturbances such as flicker and harmonics. These disturbances are due to the nonlinear electromagnetic and thermal field behaviors of the AC arcs. Analysis of these nonlinear behaviors is required for improving power quality in the network. This paper presents a three-dimensional finite element modeling of the electromagnetic fields in an AC three-phase electric arc furnace. The model includes the electrodes, arcs and molten bath. Current density, voltage and magnetic field intensity in the arcs, molten bath and electrodes are predicted as a result of applying the three-phase AC voltages to the EAF. This model does not consider the instantaneous geometry of the arc, instead a constant geometry, which is adjacent to the geometry of a DC arc with a DC current equal to the RMS value of the current waveform, is considered. Electromagnetic field of the AC arc in the time-domain is also modeled using the three-dimensional finite element method. ©2009 IEEE.