Research on definition approach of modern apparent power based on dual-equivalence scheme

The definition of apparent power for unbalanced or non-sinusoidal three-phase power systems still remains a controversial issue at present. By referring to the two schools of prevailing thoughts, i.e. the theoretical approach and the practical approach, a new definition methodology for the apparent power is proposed and deducted, which is called the dual-equivalence approach. A detailed comparative investigation regarding these three approaches is carried out in the paper with deliberately designed cases study to demonstrate their application behavior. The analyzed results indicate that, the calculation of apparent power by the dual-equivalence approach does not subject to direct impacts from either the line parameters or the no-load loss formation type, and renders preferable adaptability and reasonableness from both the theoretical and the engineering aspects. The new approach presents an alternative way for the apparent power definition.