The instantaneous complex power applied to three-phase machines

A theory was developed to give a physical interpretation of the instantaneous power flow on a three-phase induction machine, without a neutral conductor, on any operational state. It may be extended to any three-phase load. It is a vectorial interpretation of the instantaneous reactive power theory presented by H. Akagi et al. (1984). This vectorial interpretation is based on the instantaneous complex power concept defined by A.B. Torrens (1981) for single-phase, AC, steady-state circuits, and leads to a better understanding of the power phenomenon, particularly of the distortion power. This concept has been extended by the authors to three-phase systems, through the utilization of the instantaneous space vectors. The results of measurements of instantaneous complex power on a self-excited induction generator´s terminals, during an over-load application transient, are presented for illustration