third harmonic injection pulse width modulation (THIPWM)
and space vector pulse width modulation (SVPWM) can realize basic voltage control
but their common-mode voltage (CMV) suppression capabilities are limited
along with issues such as constrained output voltage peak and high switching losses. Although SVPWM further enhances voltage utilization by optimizing switching sequences
its continuous modulation characteristics still results in increased CMV and voltage stress. While CMV can be suppressed by adjusting the distribution of zero vectors
nevertheless
it remains a pressing challenge to reduce voltage stress while maintaining the voltage-boosting capability. [Methods] To address the aforementioned issues
this paper proposed a discontinuous SVPWM (DSVPWM) strategy based on zero sequence signal injection on the basis of the conventional SVPWM method. The proposed strategy reconstructed the switching sequences by eliminating one zero vector state during the charging mode and featured a variable duty ratio. The DSVPWM strategy was applied to the inverter stage of the split-source matrix converter (SSMC). Meanwhile
the rectifier stage of the SSMC adopted the conventional SVPWM strategy to achieve the maximum voltage utilization. [Results] Simulation analyses were performed on the Matlab/Simulink platform. The simulation results demonstrated that the THIPWM strategy produced the highest CMV with a peak value of 533.8 V. The SPWM and SVPWM strategies delivered similar CMV
with peak values of 532.9 V and 532.4 V
respectively. In contrast
the proposed DSVPWM strategy effectively suppressed CMV
reducing its peak value to 289.7 V. In terms of output current quality
the SPWM strategy had the maximum total harmonic distortion (THD) of output current at 4.38%
while the proposed DSVPWM strategy achieved the lowest THD of only 0.44%. The experimental waveforms obtained from the hardware platform were highly consistent with the simulation results
which further verified the effectiveness of the proposed strategy. [Conclusion] Compared with the SPWM
THIPWM and SVPWM strategies
the SSMC CMV can be better suppressed under the DSVPWM strategy proposed in this paper
with lower THD of output current and smaller voltage stress