反激式光伏并网微逆变器的设计与优化

发布时间：2018-06-13 12:28

本文选题：太阳能 + 微逆变器　；参考：《中南大学》2014年硕士论文

【摘要】：由于全球范围内的能源危机以及人们对环境保护的强烈诉求,使得努力寻求清洁的可再生的替代能源成为了世界性的研究课题。太阳能因其众多天然优点成为目前最具利用前景的替代能源。其中,最主要的太阳能利用方式之一就是组建太阳能并网发电系统。微逆变器组建的分布式发电系统相比集中式发电系统具有高可靠安全性、高MPPT效率、高可扩展性等卓越性能,因而微逆变器的研究具有重大意义。本论文研究对象为磁性元件少、控制简单的反激式并网微逆变器。首先对比分析工作于不连续导电模式以及连续导电模式的反激式微逆变器的优缺点,重点研究工作于连续导电模式下的交错反激式微逆变器。然后详细分析了连续导电模式下微逆变器主电路的工作原理,并设计了有源箝位电路,分析了有源箝位电路的工作原理及实现主开关管的零电压开通条件。接着,本论文详细设计了额定功率为250W的连续导电模式的微逆变器,包括功率电路设计、功率器件选型及功率器件损耗计算,并根据传统连续导电模式的控制方法设计了闭环控制系统。通过仿真和实验验证发现传统控制方法根据理想情况所设计的前馈补偿控制方案存在缺陷,很大程度上影响了微逆变器的输出电流质量。本文根据实际情况提出了一种新的基于分段前馈补偿的输出电流优化方法,此方法能明显降低微逆变器全功率段输出电流的谐波畸变率,且在中小功率段对输出电流质量的改善尤为显著。最后,在Matlab/Simulink上搭建了仿真平台,并根据本文设计方案研制了一台以STM32为核心控制器的250W交错反激式微逆变器样机,仿真和实验结果证明了本文提出的方法的可行性。
[Abstract]:Because of the energy crisis in the world and the strong demand for environmental protection , efforts are made to seek clean and renewable alternative energy sources . Solar energy has become one of the most promising alternative energy sources because of its many natural advantages . One of the most important solar energy utilization modes is to form a solar grid power generation system .

In this paper , the advantages and disadvantages of flyback micro - inverter with less magnetic element and simple control are studied . Firstly , the advantages and disadvantages of flyback micro - inverter working in discontinuous conduction mode and continuous conduction mode are analyzed . The working principle of the main circuit of micro - inverter in continuous conduction mode is analyzed . Then , the active clamping circuit is designed . The working principle of active clamping circuit is analyzed and the zero - voltage opening condition of main switch tube is realized .

In this paper , the micro - inverter of continuous conduction mode with rated power of 250W is designed in detail , including power circuit design , power device selection and power device loss calculation , and closed loop control system is designed according to the control method of traditional continuous conduction mode .

Finally , the simulation platform is built on Matlab / Simulink , and a 250W interleaved flyback micro - inverter prototype with STM32 as the core controller is developed . The simulation and experimental results show the feasibility of the proposed method .
【学位授予单位】：中南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM615;TM464

【参考文献】