Powers of Asymmetrically Supplied Loads in Terms of the CPC Power Theory

Power related phenomena in three-phase, three-wire circuits with linear time-invariant (LTI) loads supplied with asymmetrical sinusoidal voltage are investigated in this paper. The study is based on the concept of the Currents’ Physical Component (CPC) power theory. It is shown that the supply current of LTI loads with sinusoidal asymmetrical voltage, as in the case of symmetrical voltage, is composed of only three physical components, the active, reactive and unbalanced currents. Consequently, loads in such conditions can be characterized by the active, reactive and unbalanced powers. The equivalent and unbalanced admittances of three-phase loads at symmetrical supply voltage are constant, independent on the supply voltage, parameters. The paper shows that these parameters at asymmetrical supply depend on the voltage asymmetry.