传统的二极管钳位型多电平拓扑存在直流母线电容电压不平衡的问题。提出一种开关电容和二极管钳位组合式的多电平拓扑,介绍了其结构组成和工作原理。该拓扑将开关电容电路和二极管钳位电路有机地结合起来,充分利用两部分电路的工作特点,不但具有平衡直流母线电容电压的功能,而且可以用多种升压方式实现升压输出,同时使用的元器件数量较少。最后通过一个五电平电路的仿真和实验验证了本拓扑的有效性。
The main problem of the traditional diode-clamped topology is the voltage unbalance of the DC link capacitors. A new topology which was the combination of switched-capacitor and diode-damped circuits was proposed. The structure and the operation principle of the new topology were discussed. Both advantages of the switched-capacitor and the diode-clamped circuits were brought into full play in the topology by the combination of the two circuits. Not only the new topology balanced DC link capacitors' voltage, but also could boost the output voltage with kinds of boosting modes, and the less power elements were used. Finally the validity of the new topology was confirmed by simulations and experiments on a five-level inverter.