Wavelet based instantaneous reactive power calculation method and a power system application sample

Abstract

In this study, an instantaneous reactive power calculation method that is based on wavelet system was recommended by taking generalized instantaneous reactive power theory as basis. Validity of calculation method was indicated in a sample power system. For that purpose, generalized instantaneous reactive power theory and wavelet based instantaneous reactive power calculation method were compared for same load, instantaneous active, reactive powers and currents. It was observed that the difference between result values were as small as to be ignored. For the study, firstly instantaneous current and phase-ground voltage values were acquired at the sampling rate of 0.000625 seconds, and then voltages and currents were decomposed into approximation and detail coefficients with three-level multiresolution analysis. Instantaneous active and reactive power values and instantaneous active and reactive current values were determined on various frequency resolutions with scalar and vector products of these decompositions. Thus, instantaneous active and reactive power values that were directly drawn from the source by main harmonic and add number harmonic currents were calculated without applying an additional frequency analysis. © 2011 Praise Worthy Prize S.r.l. - All rights reserved.