عنوان مقاله [English]
The rapid increase of non-linear loads in the last three decades has caused electrical quantities such as voltages and currents in 3-phase distribution systems to become distorted waveforms. This paper reviews, explains and discusses some new concepts, definitions and new available theory in the unbalanced and distorted systems. The usefulness of the proposed practical definitions is investigated by means of applying them to the real-world measurements of a three-phase electric arc furnace voltages and currents. Finally, the main power terms such as fundamental and non-fundamental power components, harmonic pollution, phase unbalance, active, reactive nonactive and distortion components are evaluated for a 3-phase arc furnace.