Shunt Active Power Filter Enhancement by Means of Frequency-locking Complex Adaptive Linear Combiner

Abstract

This article aims to improve the dynamic performance of shunt active power filters that implements their control systems in the synchronous reference frame in order to compensate non-linear loads. In synchronous-based control systems, two parts play an important role for perfect compensation: the phase-locked loop system and the harmonic extraction algorithm. Hence, this article proposes a sophisticated phase-locked loop system based on a new frequency locking complex adaptive linear combiner and an advanced harmonic extractor algorithm based on a new combined particle swarm optimization adaptive linear combiner. The objective of the first algorithm is to simultaneously and shortly estimate the fundamental of amplitude, phase angle, and frequency of the point of common coupling voltage for providing undistorted feedbacks for the control system and keep it synchronized with the power network, while the purpose of the second one is to predict the load current harmonics for the synchronous reference frame control, quickly, precisely, and dynamically. As a result, it can be claimed that shunt active power filters equipped with the proposed control system would be able to fully compensate harmonic current distortions injected by non-linear loads, even though there are frequency deviations, voltage harmonics, and sudden load changes in the system. © 2016, Copyright © Taylor & Francis Group, LLC.