摘要
在串联分布式光伏系统中,若母线电压为固定值,易使分布式最大功率跟踪控制(Distributed Maximum Power Point Tracking,DMPPT)失效,造成功率的损失。通过逆变器可调节母线电压,但调节能力受电网电压的限制。因此,提出了一种新型的电路结构,在光伏组件串联侧和逆变器之间添加全局功率优化器(Global Power Optimizer,GPO),构建串联运行总线,消除了逆变器对原母线电压范围的影响。并在此拓扑基础上,提出了一种变串联运行电压功率优化算法,通过对串联运行电压进行周期性调节,提升了最大功率跟踪控制的性能。仿真结果表明,在光照严重不均的情况下,系统依然快速、稳定的工作在最大功率点处。
In the cascaded distributed photovoltaic system, it can easily make the distributed maximum power tracking control（DMPPT） fail and cause significant loss of the power if the bus voltage is constant. Although the bus voltage is adjustable through the inverter, the regulating ability is limited by the grid voltage. Therefore, this paper proposed a new-type topology by means of adding a global power optimizer（GPO） between the cascaded part of DC Module and the DC side of inverter, which builds the serial bus and eliminates the influence of inverter for the original bus voltage range. On the base of this topology, a power optimization algorithm based on the variable series operating voltage is proposed, which improves the performance of the DMPPT by means of the periodically adjustment of the variable series operating voltage. The simulations reveal that photovoltaic system can work fast and stable in the maximum power point under complex and serious unbalanced lighting conditions.
出处
《可再生能源》
CAS
北大核心
2016年第4期494-499,共6页
Renewable Energy Resources
基金
江苏省高校自然科学基金项目(14KJB470010)
