【摘要】 为改善传统多电平逆变器有源器件数量较多以及扩展结构复杂的问题，该文提出一种降低器件数量且可模块化扩展的多电平逆变器。该逆变器由分压电容单元、开关电容单元和两个半桥组成，使用1个直流电源、4个电容、8个开关管和2个二极管实现2倍电压增益和九电平交流输出电压。该逆变器通过2个半桥代替后端H桥转换输出电压极性，可以有效降低开关管总电压应力；在所提逆变器的模块化扩展结构中，电容逐级充电的工作方式进一步提高了电压增益和输出电平数。该文研究逆变器的工作状态、调制策略、电容分析、参数计算并进行拓扑对比。最后，通过仿真与实验验证了所提逆变器的可行性和理论分析的正确性。更多还原

【Abstract】 In order to improve the problems of the large number of active components and the complex expansion structure of the traditional multilevel inverter, this paper proposes a multilevel inverter that reduces the number of components and can be modularly expanded. The inverter is composed of a voltage divider capacitor unit, a switched capacitor unit and two half bridges. It uses 1DC power supply, 4 capacitors, 8 switches and 2 diodes to achieve double voltage gain and a nine-level AC output voltage. Two half-bridges are used in the proposed inverter instead of the back-end H-bridge to convert the output voltage polarity, which can effectively reduce the total voltage stress of the switches. In the modular expansion structure of the proposed inverter, the step-by-step charging method of the capacitors further improves the voltage gain and the output level number. This paper includes the working states, modulation strategy, capacitance analysis, parameter calculation, and topology comparison of the proposed inverter. Finally, the feasibility of the proposed inverter and the correctness of the theoretical analysis are verified through simulation and experiment.更多还原