一种优化的级联型多电平变换器拓扑

本文提出了一种优化的级联型多电平变换器，它可以由任意个任意类型的H-桥单元级联构成。各个H-桥通过设置合适的直流电压比，可以得到最大电平数的输出。相对于传统的级联型拓扑，在得到相同输出电平的情况下，新拓扑可以使用较少数量的开关器件和较少数量的独立电压源，从而简化电路，降低成本。本文以两电平H-桥(2-H)和飞跨电容型三电平H-桥(3-H)级联构成的拓扑为例进行了分析研究，并采用混合调制的方法通过仿真验证了该优化拓扑的可行性。

An Optimal Cascaded Multilevel Inverter Topology

An optimal cascaded multilevel inverter topology is proposed in this paper, which is composed by any number of any kinds of H-bridge cells. By setting proper separate voltage sources for different cells, the maximum output levels can be got. Relative to conventional cascaded topology, the new topology needs fewer switching devices and fewer separate voltage sources when producing the same number of output levels, which simplifies circuit and saves costs. As an example, a topology composed by a two-level H-bridge cell and a three-level flying-capacitor H-bridge cell is researched. The hybrid modulation is used in the topology. Simulated results show validity.