A DPWM modulation strategy to reduce common-mode voltage for indirect matrix converters based on active-current vector magnitude characteristics

based on the characteristics that the magnitude of active-current vector in the rectifier stage is zero when the zero-voltage vector is used in the inverter stage, a novel Discontinuous Pulse Width Modulation (DPWM) strategy for the indirect matrix converter is proposed in this paper to reduce the common-mode voltage (CMV). In this DPWM strategy, the reference current vector in the rectifier stage is synthesized by two adjacent active-current vectors, and the reference voltage vector in the inverter stage is synthesized by two adjacent active-voltage vectors and one zero-voltage vector. When the inverter stage utilizes one zero-voltage vector, the active-current vector with zero magnitude among the two adjacent active-current vectors, which produce smaller CMV, is selected to apply in the rectifier stage. The DPWM strategy reduces the peak magnitude of common-mode voltage by 42.3% while maintaining the advantages of the traditional DPWM modulation strategy such as less hard switching times in a carrier period, wide voltage transfer ratio, and input/output performance. Finally, the effectiveness of the modulation strategy is verified by simulation and experiments.