Coordinated Capacitor Voltage Balancing Method for Cascaded H-bridge Inverter with Supercapacitor and DC-DC Stage  

作　　者：Ye Zhang Zixin Li Fanqiang Gao Cong Zhao Yaohua Li 

机构地区：[1]IEEE [2]Key Laboratory of High Density Electromagnetic Power and Systems(Chinese Academy of Sciences),Institute of Electrical Engineering,Chinese Academy of Sciences,Haidian District [3]University of Chinese Academy of Sciences,Shijingshan District

出　　处：《CES Transactions on Electrical Machines and Systems》2024年第2期191-201,共11页中国电工技术学会电机与系统学报（英文）

基　　金：supported in part by the CAS Project for Young Scientists in Basic Research under Grant No. YSBR-045;the Youth Innovation Promotion Association CAS under Grant 2022137;the Institute of Electrical Engineering CAS under Grant E155320101。

摘　　要：Cascaded H-bridge inverter(CHBI) with supercapacitors(SCs) and dc-dc stage shows significant promise for medium to high voltage energy storage applications. This paper investigates the voltage balance of capacitors within the CHBI, including both the dc-link capacitors and SCs. Balance control over the dc-link capacitor voltages is realized by the dcdc stage in each submodule(SM), while a hybrid modulation strategy(HMS) is implemented in the H-bridge to balance the SC voltages among the SMs. Meanwhile, the dc-link voltage fluctuations are analyzed under the HMS. A virtual voltage variable is introduced to coordinate the balancing of dc-link capacitor voltages and SC voltages. Compared to the balancing method that solely considers the SC voltages, the presented method reduces the dc-link voltage fluctuations without affecting the voltage balance of SCs. Finally, both simulation and experimental results verify the effectiveness of the presented method.

关 键 词：Cascaded H-bridge inverter(CHBI) Hybrid modulation strategy(HMS) Capacitor voltage balancing DClink voltage fluctuation Supercapacitor(SC) 

分 类 号：TM53[电气工程—电器] TM464