Evaluation of control strategies for parallel active filter under different supply voltage conditions

This paper focuses on the various control techniques of reference current generation for harmonic mitigation with a view to the problem of source current harmonics caused by the non-linear loads. All the techniques are analyzed mathematically and simulation results are compared in terms of compensation performance under different supply voltage conditions. Control strategies analyzed are the Instantaneous power theory, Symmetrical current component theory and an improved d-q theory. Simulation results are obtained under sinusoidal voltage source condition and distorted source voltage condition with voltage source convertor. The comparison and effectiveness of all the methods are based on the mathematical and theoretical analysis. Simulation results have been obtained with MATLAB employing a three phase three wire test system.