Comparison of Reference Current Generation Techniques for Non-active Power Compensation Under Distorted and Unbalanced Conditions

This article presents a comparison of two reference non-active current generation techniques for power compensation under unbalanced and distorted source voltage conditions and unbalanced loads. Two techniques are evaluated: Fryze´s general equation (FGE) and the positive sequence magnitude by the synchronous reference frame method (PSM-SRF). These techniques are evaluated in terms of the compensation performance of a three-phase shunt active filter in a four wire power system. The reference current generation techniques are stated theoretically and the comparison is evaluated on simulation and experimental results. The more important results are that both techniques allow harmonic and reactive components elimination under any conditions, the unity power factor correction is achieved only by the FGE technique, but this technique balances the source currents only under distorted voltage and unbalanced load conditions, and source currents balancing and neutral current elimination are achieved under any condition only by the PSM-SFR technique