Power theory of electric circuits: common data base of power related phenomena and properties

This paper can be considered as an incentive for a cognition and discussion upon the very fundamentals of the power theory of electric circuits: what is the power theory; why there is a quest for it; what has been achieved; what still should be done. Also it is suggested that various power and current equations developed for describing power properties of electric circuits, in particular, circuits with non-sinusoidal waveform of voltages and currents, as well as various conclusions and interpretations of power phenomena should not be considered as various power theories. They form rather a single power theory comprehended as a common data base of power related phenomena in electric circuits.