A Three-Phase Adaptive Notch Filter-Based Approach to Harmonic/Reactive Current Extraction and Harmonic Decomposition

This paper introduces a new three-phase adaptive notch filtering approach for the extraction of harmonic and reactive current components for use in grid-connected converters. The main function of this phase-locked loop-less method is to provide synchronized harmonic and reactive current components for control purposes. Moreover, this method is capable of detecting a selective order of harmonics. This feature is useful where elimination of certain harmonics is of concern. The theoretical analysis is presented and the performance of the method is experimentally evaluated. The methodology is applicable for a wide range of equipment like regenerative converters, distributed generation systems, as a basis for detection of the reference signals.