Comparative analysis of reactive power definitions in the presence of harmonics

Abstract

In this paper, the most significant definitions of reactive power in single-phase and three-phase three-wire systems with non-sinusoidal voltages and currents are presented. Comparative analysis of these definitions has been performed. Fundamental principles on which these definitions rely are stated, and the application of these definitions to solving the problems of compensation is explained. Contrary to single-phase or three-phase symmetrical systems operating under sinusoidal conditions, reactive power compensation in systems operating under non-sinusoidal conditions does not result in maximal efficiency of electric energy delivery. Less efficiency in comparison to the theoretical maximum is being explained by the presence of harmonics and asymmetries in the system. Therefore, in the context of the reduction of losses during electric energy delivery to the load, the possibilities of nonactive power reduction should be contemplated instead of the possibilities of reactive power reduction.

Keywords

• reactive power
• power definition
• harmonics