A new frequency domain approach for flicker evaluation of arc furnaces

In this paper, flicker magnitudes of rapidly varying loads are evaluated by means of a new frequency domain method. Analytical expressions of the instantaneous flicker sensation are obtained in terms of interharmonic voltages. The dynamic response of flicker magnitudes of such loads can be clearly described with this analysis, as well as the individual contribution of each interharmonic to the flicker sensation. The proposed method, applied to the voltages of dc and ac arc furnaces, provides very satisfactory results that have been validated with measurements performed with the standardized IEC flickermeter. Index Terms--Arc furnaces, flicker, flickermeter, frequency domain analysis, interharmonic, power quality.