Do Energy Oscillations Degrade Energy Transfer in Electrical Systems?

Abstract

There is the view, widespread in the electrical engineering community, that the effectiveness of energy transfer in electrical systems, thus the power factor, is reduced by energy oscillations which, according to this view, are the cause of the reactive power. This view is challenged in this article. It demonstrates on a variety of circuits that this view is not right. Power factor can decline without energy oscillations, or energy oscillations do not cause its decline. In addition, the reactive power can occur in the absence of energy oscillations or their presence does not cause the reactive power. This observation has not only cognitive but practical merit as well. According to Instantaneous Reactive Power p-q theory, to improve the power factor, energy oscillations between the supply source and the load should be compensated. Because this conclusion is erroneous, an active power filter, controlled according to this recommendation in the presence of the supply voltage distortion or/and asymmetry, instead of improving the power factor can worsen it. The physical meaning of the reactive power is also investigated in this article, with the conclusion that there is no physical phenomenon in electrical systems that could be described in terms of reactive power.