摘要
针对非隔离全桥并网逆变器共直流和交流母线并联运行系统,研究功率电路拓扑并联工作及入网电流解耦的条件。深入分析了各种全桥拓扑形式和PWM调制方式的逆变器并联运行的等效模态,指出双极性PWM逆变器并联时,模块间入网电流自然解耦;单极性倍频PWM逆变器并联时,模块间电流存在高频耦合,但基波分量解耦;单极性PWM逆变器并联时,模块之间高频耦合并导致基波分量耦合、不可并联运行。带共模电流抑制的全桥并网逆变器拓扑也可实现入网电流的自然解耦。分别搭建了上述几种逆变器的并联运行实验系统,实验结果证明了分析的正确性。
Current coupling among the transformerless non-isolated grid-connected inverter modules is researched with the current decoupling condition given by analyzing the equivalent operation modes of the inverters mentioned with different topologies and modulations.Analysis reveals that the bipolar PWM inverters can be operated in parallel with current decoupling naturally.Unipolar double frequency PWM inverters can be operated in parallel with harmonic current of switching frequency coupled and fundamental components decoupled.Unipolar PWM inverters can not be operated in parallel with current coupling.Inverters with common-mode current eliminating cells,such as H5 and HERIC topology,can achieve current decoupling naturally in parallel operation.Grid-connected photovoltaic power systems with inverter modules mentioned are built respectively.And experimental results verify the analysis.
出处
《电工技术学报》
EI
CSCD
北大核心
2012年第8期21-27,41,共8页
Transactions of China Electrotechnical Society
基金
江苏省科技成果转化基金(BA2008001)
台达环境与教育基金会<电力电子科教发展计划>(DREG2010007)资助项目
关键词
逆变器
并联
解耦
冗余
并网
Inverter
parallel operation
current decoupling
redundancy
grid-connected
