摘要
准Z源级联H桥逆变器(QZS-CHI)在分布式发电中具有广阔的应用前景。传统调制方法的直通加入过程会使开关频率倍增,进而导致开关损耗较大。该文提出一种多调制波移相正弦脉宽调制方法,将直通量植入开关切换时刻,可有效降低损耗。由于直通占空比与调制比存在约束关系,会对输出电平数造成影响,分析了QZS-CHI的输出电平数与调制比、模块数、直通占空比的关系。通过搭建级联6模块QZS-CHI的仿真模型及试验样机,验证开环条件下调制方法和输出电平分析的正确性,实验结果表明,新提出的调制方法最大效率可达96.64%,相比传统调制方法,可提升1.71%的效率点。
Quasi-Z-source cascaded H-bridge inverters(QZS-CHI)have broad application prospects in distributed generation.In the conventional modulation method,the insertion of the shoot-through state doubles the switching frequency,resulting in large switching loss.In this paper,a multi-modulation waveform phase-shifting SPWM method is proposed by inserting the shoot-through state into the switching moment,which can effectively reduce the switching loss.Since the shoot-through duty ratio is constrained by the modulation ratio,the level of the output voltage is affected.The relations of the output voltage level with the modulation ratio,the number of modules and the shoot-through duty ratio are analyzed in this paper.By constructing the simulation model and test prototype of the cascaded 6-module QZS-CHI,the modulation method and the output level analysis under open-loop conditions are verified.The experimental results show that the maximum efficiency of the proposed modulation method can reach 96.64%,which is 1.71%higher than that of the traditional modulation method.
作者
王剑
张芮
刘洋
李媛
Wang Jian;Zhang Rui;Liu Yang;Li Yuan(Sichuan Energy Internet Research Institute Tsinghua University,Chengdu 610042 China;Institute of Aeronautics and Engineering Civil Aviation Flight University of China,Guanghan 618307 China;College of Electrical Engineering Sichuan University,Chengdu 610065 China)
出处
《电工技术学报》
EI
CSCD
北大核心
2020年第16期3470-3477,共8页
Transactions of China Electrotechnical Society
关键词
准Z源
级联多电平逆变器
调制
输出电压
多模块
Quasi-Z-source
cascaded multilevel inverters
modulation
output voltage
multimodule
