| This article firstly gives introduction about two definitions of reactive power widely used under non-sinusoidal waveforms, and there are some analyses of theory and error between Artificial Reactive Power and Natural Reactive Power.When there are harmonics on the power system, influences of measurement process of reactive power caused by harmonic are analyzed, for example the influences of inductor and electric power measurement. It is deduced theoretically that non-linear load, rather than linear load, generates harmonics, which translates part of fundamental reactive power absorbed from power system into harmonic reactive power injected into the power system. The rationality of electric power measurement for linear and non-linear load is studied, and as a result some rational advices are addressed here.On the basis of the above analyses, the AC sample method is discussed. This paper introduces one type of Hilbert Digital Filter applied widely in reactive power measurement. In this paper, combining Pleisiochronous with Hilbert DF, the pleisiochronous Hilbert DF arithmetic is used to measure reactive power.Finally, Data Management System of Multifunction watt-hour meter and the software is introduced in this paper. |
