Electric arc furnace (EAF) is one of the typical nonlinear loads in distribution network, which causes power quality problems such as harmonics and voltage flicker. In this paper, a time-domain simulation of AC EAF model for the research of power quality is established in MATLAB/Simulink and a simple multi-step parameter estimation method is proposed for a given EAF load. Considering the specific structure of EAF transformer, the arc model is obtained by combination and modification of classical Cassie and Mayr equations. The arc model is dynamically modulated by superimposing the sinusoidal and band-limited white noise signal to simulate the actual working conditions. The comparison between results from simulation and data from real measurement shows that the proposed model is capable of describing the time-varying, nonlinear and unbalanced characteristics of EAF accurately, which provides a reference for the research of the low-voltage side of the EAF transformer power quality problems.

electric arc furnace; harmonics; voltage flicker; power quality