PWM strategy of single-phase to three-phase matrix converters for reducing output voltage harmonics and number of commutations

This paper presents a pulse-width modulation (PWM) strategy of single-phase to three-phase matrix converters for reducing output voltage harmonics and number of commutations. The authors have already proposed a PWM strategy to decrease the number of commutations to four in all three phases during one control period. This paper describes a procedure for further reducing number of commutations to three in all three phases by permitting one duty cycle to be assigned a value of zero. This procedure is facilitated by using detected output current values to calculate the continuously varying duty cycles in a control period. An algorithm to select duty cycles with reducing output voltage harmonics during these three times commutation is also proposed. The effectiveness of the proposed PWM strategy has been verified by experiments.