Optimization of the four step switching sequence used by a single-phase AC-AC converter to compensate voltage sags and swells

In this paper, an analysis and selection of the optimal operation sequence that can be achieved with the four step switching technique is presented. The sequence is chosen in base to the operation features of a single-phase AC-AC converter used to compensate voltage sags and swells. The energy dissipation of the AC-AC converter switches as well as an easy implementation and reliability are considered. The reliability of the converter is increased due to the advantages that present the optimal sequence. The switch commutation and conduction looses arc equilibrated, guaranteeing that the energy dissipated by each switching device will be the same. The performance of the AC-AC converter with the selected sequence is presented by means of simulation and experimental results.