The nine-arm modular multilevel converter (9A-MMC) has been recently proposed as a reduced MMC topology variation for six-phase drive applications, with 25% reduction in the number of employed arms and associated components, compared to a standard dual three-phase MMC, however with a limited output voltage amplitude. This paper proposes a hybrid 9A-MMC comprised of half-bridge submodules (SMs) in both the upper and lower arms, and full-bridge SMs in the middle arms. By employing the negative-voltage state of the full-bridge SMs, the hybrid 9A-MMC avoids the limitations imposed on the dc-link voltage utilization, while achieving further reduction in the component count, compared to a standard 9A-MMC with identical half-bridge SMs. The operating principles of the proposed hybrid 9A-MMC are illustrated with mathematical analysis, whereas its characteristics are verified through both simulation and experimentation. An assessment of the proposed topology quantifying its employed components is also provided, in comparison to other MMC-based six-phase machine drives.

中文翻译：

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一种用于中压六相电机驱动的混合九臂模块化多电平转换器

九臂模块化多电平转换器 (9A-MMC) 最近被提出作为六相驱动应用的一种减少 MMC 拓扑变化，与标准双三相相比，采用的臂和相关组件的数量减少了 25%。相 MMC，但是输出电压幅度有限。本文提出了一种混合 9A-MMC，它由上臂和下臂的半桥子模块 (SM) 和中间臂的全桥 SM 组成。通过采用全桥 SM 的负电压状态，与具有相同一半的标准 9A-MMC 相比，混合 9A-MMC 避免了对直流链路电压利用率施加的限制，同时进一步减少了组件数量-桥接短信。所提出的混合 9A-MMC 的工作原理通过数学分析来说明，而它的特性是通过模拟和实验验证的。与其他基于 MMC 的六相电机驱动相比，还提供了对拟议拓扑的评估，量化了其采用的组件。