How to Define Three-phase Apparent Power?

Leszek S. CZARNECKI

Abstract

The article clarifies the confusion around various definitions of apparent power in three-phase systems. It demonstrates that arithmetical and geometrical definitions of that power in three-phase systems with unbalanced loads yield erroneous values of the threephase apparent power and the power factor. When voltages and currents are sinusoidal, then the correct values of the apparent power and the power factor can be calculated when Buchholz's definition is used. When these quantities are distorted, the correct values of the apparent power and the power factor can be calculated using the definition proposed by the author of this article.

Keywords

Unbalanced loads, three-phase vectors, three-phase rms, power factor

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Bilbiography

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