On the Definition of Apparent Power

In this paper, the widely recognised apparent power definitions, including Arithmetic, Vector, IEEE standard, DIN standard, and the apparent power definition of Mayordomo and Usaola, are rigorously reviewed. The objective is to analyze their abilities in measuring the system’s power transfer efficiency through a specially derived apparent power that factors total line losses with and without reactive power compensation. The methodology involves examining two major compensation strategies: minimum line loss (MLL) and sinusoidal and balanced current (SBC), within a representative nonsinusoidal and unbalanced test system. Results indicate that unbalance among the resistances of neutral and phase lines significantly affects the system’s power transfer efficiency under nonsinusoidal and unbalanced conditions. The findings suggest that Mayordomo and Usaola’s apparent power definition is effective for accurately measuring power transfer efficiency in these systems, while the accuracy of other definitions is heavily dependent on the line resistance unbalance. Additionally, the type of compensation strategy employed does not significantly impact the accuracies of the apparent power definitions.