AC-SPWM-cycloconverter based on an extended chopper scheme

A novel cycloconverter based on chopper scheme is proposed, which is entirely different from the former cycloconverters based on phase-shift control, so leading to higher power factor than that of the latter, also in price of minimum power device number. Two kinds methods are derived for determining the relationships between Duty-Cycle and other parameters by means of different Area-Equivalent criteria. The single and 3-phase topologies and the ac-SPWM control strategy are introduced, which can realize variable frequency and variable voltage operation at the same time. Also some key simulations and experimental results show the validity of the conversion as well as the applicable prospect of the new cycloconverter-category.