Harmonic Elimination in Single Phase Systems Using a High Performance Hybrid Active Filter

In recent years, more and more single phase loads are used in house hold appliances, electronic equipments and etc; these loads have a significant harmonic spectrum in power source current. Although rating of these load for a single consumer is low, as the number of consumers connected to a feeder is increased; harmonic currents with high THD are drawn from power system which can lead to high losses for end users and equipments connected in power system. In this paper, a fully-digital-controlled hybrid series active filter for harmonic elimination and reactive power compensation is presented in single phase systems. Studied configuration is a cheap and high efficiency method to mitigate adverse effects of single phase loads in power distribution system. The hybrid filter composed of two single tuned LC filters and a small-rated active filter. A new control method is proposed for active filter whose important advantage is that it is applicable in the most configurations of power electronic converters such as shunt and series active filters. Another advantage of the presented control method is its fast speed response to load changes, less than 1 cycle. Simulation results using MATLAB program shows the effectiveness of the proposed method. In addition, a hybrid series active filter is implemented verifying the accuracy of the proposed control method Copyright (C) 2011 Praise Worthy Prize S.r.l. - All rights reserved.