摘要
针对现有多电平逆变器存在拓扑结构复杂、开关器件总电压应力高和串联电容电压不平衡的问题,提出了一种新型的开关电容七电平逆变器。通过同相层叠脉宽调制策略,合理地控制开关管使得三个电容器与直流电源串并联分时运行,实现了三倍升压增益的七电平输出。该逆变器采用单个直流输入电源,不仅具有结构简单、器件少、升压能力强和电容电压自平衡等优势,并且负载端不采用逆变H桥来改变输出电平极性,从而降低开关器件的总电压应力。分析了逆变器的拓扑结构、工作原理、电容电压自平衡、调制策略、电容参数和电流应力,并从开关管数量、二极管数量、电容数量、总开关电压应力和升压增益5个方面与现有拓扑进行了比较分析,充分证明所提拓扑的实用性。最后实验结果验证了该拓扑的可行性。
Aimed at the problems of complex topologies,high total standing voltage of switches,and unbalanced series capacitor voltages in the existing multilevel inverters,a novel seven-level inverter based on switched-capacitor is proposed.By adopting the phase disposition pulse width modulation strategy,three capacitors are reasonably controlled in series/parallel with the DC source,so that the seven-level output with a triple boost gain is realized.The proposed inverter uses only one single DC source,so it has advantages such as a simple structure,fewer components,high boost gain and self-balanced capacitor voltage.In addition,it does not use the H-bridge to change the polarities of output levels,thus reducing the total standing voltage of switching devices.The topology,working principle,capacitor voltage self-balance,modulation strategy,capacitor parameter and current stress are analyzed,and five aspects including the numbers of switches,diodes and capacitors,the total standing voltage and the boost gain are compared with those of the existing topologies,which fully proves the practicality of the proposed topology.Finally,the feasibility of this topology was verified by experimental results.
作者
张国鑫
陈仕铠
叶远茂
ZHANG Guoxin;CHEN Shikai;YE Yuanmao(School of Automation,Guangdong University of Technology,Guangzhou 510006,China)
出处
《电源学报》
CSCD
北大核心
2024年第2期113-120,共8页
Journal of Power Supply
基金
国家自然科学基金资助项目(51907033)。
关键词
多电平逆变器
开关电容
电压自平衡
脉宽调制
Multilevel inverter
switched-capacitor
voltage self-balance
pulse width modulation
