【目的】在现有调制策略中，正弦脉宽调制(SPWM)、三次谐波注入脉宽调制(THIPWM)以及空间矢量脉宽调制(SVPWM)均可实现基本电压控制，但其抑制共模电压(CMV)能力有限，同时存在输出电压峰值受限、开关损耗较大等问题。尽管SVPWM通过优化开关序列进一步提升了电压利用率，但其连续调制特性仍会造成CMV与电压应力升高。虽然可通过调整零矢量分布抑制CMV，但如何在保持升压能力的同时降低电压应力，仍是亟待解决的难题。【方法】针对上述问题，本文在SVPWM策略的基础上，提出一种基于零序信号注入的不连续空间矢量脉宽调制(DSVPWM)策略。该策略通过消除充电状态下的1个零矢量状态，重构开关序列，并且具有可变占空比。将DSVPWM策略应用于分离源矩阵变换器(SSMC)的逆变级；为获得最大电压利用率，SSMC的整流级采用传统的SVPWM策略。【结果】基于Matlab/Simulink平台进行仿真分析。结果表明，THIPWM 策略的CMV最大，峰值为 533.8 V；SPWM与SVPWM 策略的CMV相近，峰值分别为532.9 V和532.4 V；相比之下，本文所提DSVPWM策略可有效抑制CMV，将其峰值降至289.7 V。在输出电流方面，SPWM策略的输出电流总谐波失真(THD)最大，为4.38%，而本文所提DSVPWM策略的输出电流THD仅为0.44%，谐波含量最低。基于硬件平台的试验波形与仿真波形高度吻合，进一步验证了所提策略的有效性。【结论】相较于SPWM、THIPWM和SVPWM策略，在本文所提DSVPWM策略下，SSMC的CMV能够得到更好抑制，输出电流THD更小，电压应力较小，但电压增益略有下降。

[Objective] Among existing modulation strategies, sinusoidal pulse width modulation (SPWM), 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, yet a slight drop in voltage gain.

国家自然科学基金(62473247);国家电网公司科技项目(SGZJLS00DKJS2400361)