This article reports the findings of ongoing research into the nature
and extent of electric fluctuations occurring-in electric arc furnaces
(EAFs). These fluctuations are indicators of the state of the furnace
system and may serve as precursors for use in predictive control of t
he system. Current and voltage wave forms taken from a small-scale, 20
0 lb capacity alternating current EAF are used to characterize the mot
ion of the arc column. Wave forms were analyzed using nonlinear dynami
cs and digital signal processing techniques. Analysis indicates that t
he observed system behavior is suggestive of chaotic dynamics, with ph
enomena occurring on several time scales.