Powers and compensation in circuits with nonsinusoidal and asymmetrical voltages and currents Part 4. Powers in un balanced three -phase circuits with nonsinusoidal voltages and currents

Abstract

This series of papers is devoted to power properties and compensation in circuits with nonsinusoidal voltages and currents. In the case of three-phase circuits, considerations have to start with such circuits at sinusoidal voltages and currents, however, because the known power equation (i.e. the relation between active, reactive and apparent power) of such circuits is valid only at mutually symmetrical voltages and currents. When this condition is not satisfied, this equation is erroneous even if voltages and currents are sinusoidal. Waried opinions in electrical engineering community on how the apparent power S in such circuits should be defined, is one of the major reasons for which the known power equation of three-phase systems is not valid. The analysis of various definitions of the apparent power S in three-phase systems and development, with the CPC approach, of the valid power equation of such systems at sinusoidal voltages and currents is presented in this paper.

Keywords

CPC theory, unbalanced current, unbalanced power

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Bilbiography

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