Dynamic performance of single phase active power filters using virtual two axis strategy

In this paper the orthogonal transformation technique or virtual two axis strategy which was instigated by Akagi et al in 1984 for three phase power systems has been extended by Dobrucky and Pokorny in 1999 for the determination of instantaneous power in single phase power systems. This technique is described in detail in two of the authors´ previous publications, by adopting this technique, an expression for the reference current used in an active power filter for the compensation of harmonic distortion and reactive power is derived. This expression is implemented by a digital signal processor and results in providing an excellent transient response of the filter which is demonstrated experimentally. This excellent response is realized due to the fast evaluation of the filter reference current when the two axis strategy described in this paper is used.