A unified carrier-based modulation method for direct matrix converter

This paper presents a unified carrier-based modulation method for direct matrix converter. Various types of pulse width modulation (PWM) methods are generated by using the offset voltage, changing slope of carrier waveform, and adjusting the free parameters in the modulation algorithm. The proposed method is equivalent to the space vector pulse width modulation (SVPWM) for two-level and three-level voltage source inverter (VSI). This paper also presents a new viewpoint to understand the matrix converter modulation method such as single carrier based modulation technique for two-level VSI and double carrier based modulation technique for three-level VSI. Using the proposed method, this paper presents discontinuous pulse width modulation (DPWM) for the matrix converter. Therefore, a unified simple algorithm suitable for the digital implementation of all continuous and discontinuous PWM strategies is proposed. The feasibility of the proposed modulation method has been verified by a computer simulation results. These results show that the proposed carrier-based modulation method can be implemented easily without any tables.