一种单电源九开关二倍升压九电平逆变器

Single Supply Nine-switch Double Boost Nine-level Inverter

针对现有九电平逆变器存在使用器件较多且调制策略复杂的问题,提出1种新型的开关电容九电平逆变器,其拓扑仅需1个直流电源、9个开关、2个电容和2个二极管即可输出九电平,同时实现二倍升压。该逆变器具有电容电压自平衡的能力,无需复杂的控制算法和外部均压电路来维持电容电压平衡。采用多载波层叠调制策略对该逆变器进行调制,逆变器中4对开关的工作状态互补,可以使用非门逻辑电路来降低调制策略的复杂度。首先对该逆变器的拓扑结构和工作原理进行理论分析;其次,对调制策略进行了详细介绍,并将所提拓扑与其他九电平拓扑进行比较,介绍了该拓扑的优点;最后,搭建的仿真电路和实验平台验证了所提拓扑及调制策略的可行性和有效性。

Aimed at the problems in the existing nine-level inverter such as many devices and a complex modulation strategy,a novel switched capacitor nine-level inverter is proposed.The topology of this inverter is composed of only one single DC power supply,nine switches,two capacitors and two diodes,and it can output nine levels and double the boost at the same time.The voltages of capacitors are self-balancing,and the complex control algorithm and external voltage sharing circuit are not required.The phase disposition PWM strategy is adopted to modulate the inverter.The working states of four pairs of switches in the inverter are complementary,and the NOT gate logic circuit can be used to reduce the complexity of the modulation strategy.First,the topology and working principle of the inverter are analysed theoretically.Second,the modulation strategy is introduced in detail,and the advantages of this topology are introduced by comparing it with other nine-level inverters.Finally,the feasibility and effectiveness of the proposed topology and modulation strategy were verified based on the established simulation circuit and experimental platform.