Robust Signal Processing System for Identification of Harmnonics in an Active Power Filter Application

This paper presents a robust signal processing system for tracking individual harmonic components that is suitable for selective harmonics compensation in active power filter applications. The proposed signal processing system is based on an efficient least squares algorithm that does not require matrix inversion. The proposed method can provide the individual harmonic current components with a fast response and high accuracy in real time. Furthermore, the method is capable of dealing with unbalanced conditions and tracking harmonics accurately for marginal changes in fundamental supply frequency. The extracted harmonic components are used to generate the reference signal for the active power filter. The proposed algorithm was utilized in a three-phase active power filter for compensating significant harmonics up to 13^th order. The validity and performance of the proposed individual harmonic detection method is investigated by simulation studies. Furthermore, the suitability of the proposed method in an active harmonic compensation is verified by a series of simulation and experimental studies