Meta-theory of electric powers and present state of power theory of circuits with periodic voltages and currents

Historically justified goals of the power theories development, general expectations and mathematical tools used for it are discussed in the paper. General features of the power theory of single-phase circuits with sinusoidal voltages and currents, the only commonly accepted power theory, were used as a reference for the presented discussion. Also discussed in this paper are the major issues of power theories development such as these: Should the power theory be formulated in the frequency or in time-domain? Should it be based on quantities averaged over a period or on instantaneous values? It was shown that in spite of the name power theory, the load currents rather than powers convey information on power properties of electrical circuits