PWM strategy of single-phase to three-phase matrix converters for reducing a number of commutations

This paper presents a novel PWM strategy of single-phase to three-phase matrix converters with a small capacitor compensating for single-phase instantaneous electric power fluctuation. The output voltage and input current references of the small capacitor to obtain unity input power factor are derived. The PWM strategy with the only four commutations of all the three phases during a control period is proposed. The design method of the small capacitor is derived from the control ranges of the output voltage and current. The effectiveness of the proposed PWM strategy has been verified by experiments.