Statistic Characteristic Estimations of Harmonic And Flicker on Electric Arc Furnace Feeders

This paper proposes the estimation results of the stochastic characteristics of harmonic and flicker for an AC and a DC electric arc furnace feeders. These characteristics include stationarity, normality and correlation. Besides, the statistic probability was assessed, too. The estimation and the assessment are implemented by a PC-based virtual instrumentation system. The results show that (1) most harmonic and flicker characteristics are stationary or weakly stationary during different periods of a heat cycle for both of the AC and the DC furnace feeders, but most of their probability density functions are not normally distributed, (2) the harmonic distortion and the voltage flicker of the AC furnace exceed the currently available limits, (3) the DC furnace has less impacts on power quality than the AC furnace