A multilevel dodecagonal voltage space vector generation scheme for variable-speed drive applications with single-dc-link operation requires a large value of capacitance for cascaded H-bridge (CHB) filters, when operated at lower speeds. In existing schemes, the multilevel dodecagonal structure is obtained by cascading a flying capacitor inverter with a CHB. In this paper, a new scheme has been proposed to minimize the capacitance requirement for full speed operation by creating vector redundancies using modular and equal voltage CHBs. Also, an algorithm has been developed to optimize the selection of vector redundancies among the CHBs in order to minimize the voltage ripple of the floating capacitors. The proposed algorithm considers instantaneous capacitor voltages and phase currents for optimal selection of vector redundancies. A mathematical model for capacitor voltage deviation is presented, and the effectiveness of the proposed algorithm is verified in both the simulation and the experiment.

中文翻译：

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驱动器多级十二边形电压空间矢量结构中开关电容器电压纹波的最小化


当以较低速度运行时，用于具有单直流链路操作的变速驱动应用的多级十二边形电压空间矢量生成方案需要用于级联 H 桥 (CHB) 滤波器的大电容值。现有方案中，多级十二边形结构是通过级联飞跨电容逆变器与CHB得到的。本文提出了一种新方案，通过使用模块化和等压 CHB 创建矢量冗余来最小化全速运行的电容要求。此外，还开发了一种算法来优化 CHB 之间矢量冗余的选择，以最大限度地减少浮动电容器的电压纹波。所提出的算法考虑了瞬时电容器电压和相电流，以实现矢量冗余的最佳选择。提出了电容器电压偏差的数学模型，并通过仿真和实验验证了该算法的有效性。