一种两倍升压五电平开关电容逆变器

A five level switched capacitor inverter with voltage doubling ability

开关电容型逆变器具有使用单直流电源输入、电容电压自均衡、输出谐波含量低以及高电压增益的优势。本文提出一种新型五电平逆变器拓扑,该拓扑由1个直流电源、2个浮动电容、1个电感以及4对互补开关管构成;采用多载波层叠调制策略实现开关电容与输入电源的分时串并联运行;实现了2倍电压增益、五电平输出以及电容电压自均衡;通过增加电感抑制了开关电容充电时存在的脉冲电流,降低了开关管的电流应力。此外,逆变电路中没有单独二极管器件,使得该电路具有能量双向流动的能力,扩展了电路的应用范围。本文详细分析了电路的构成及工作过程,仿真及实验结果验证了所提出的逆变器具有可行性。

Switched capacitor inverters have the advantages of using a single DC power input,capacitor voltage self-balancing,low output harmonics,and high voltage gain.This paper proposed a novel five level inverter topology,which consisted of a DC power supply,two floating capacitors,an inductor,and four pairs of complementary switches.The multi-carrier cascade modulation strategy was adopted to realize the time-sharing series-parallel operation of the switched capacitor and the input power supply.It realized double voltage gain,five level output and capacitor voltage self-balancing;By adding an inductor,the pulse current existing at the switching capacitor charging was suppressed and the current stress of the switching tube was reduced.In addition,the absence of diode devices in the inverter circuit enabled the circuit to have the ability to flow energy in both directions,expanding its application range.The paper provides a detailed analysis of the circuit composition and working process.And the simulation and experimental results verify the feasibility of the proposed inverter.