光伏发电系统与能量管理研究

发布时间：2018-04-27 05:04

本文选题：独立光伏系统 + 最大功率点跟踪　；参考：《湖南大学》2014年硕士论文

【摘要】：21世纪，世界能源紧缺和环境污染问题变得更加严重，以风能、太阳能为代表的新能源，凭借其清洁、可持续的特性得到世界各国的重视。独立光伏发电系统通常设计为偏远、没有电网覆盖的地区提供电力，具有广阔的应用空间。本文主要研究独立光伏发电系统的设计与优化，具体工作如下： 1)在局部阴影条件下光伏阵列输出功率—电压曲线为多峰值而非单峰值，常规的最大功率点跟踪策略缺乏全局寻优能力，常常陷于局部峰值，造成大的功率损失。本文通过分析局部阴影条件下光伏阵列的输出特性曲线，提出了基于辅助线，结合电流控制和扰动观察法的最大功率点跟踪策略。 2)设计了一款额定输出功率为600W高频光伏逆变器，，逆变器具备宽输入电压、高转换效率、安全、稳定的特性。逆变器前级升压DC采用推挽拓扑，使用PWM芯片SG3525作为控制核心，采用TL431配合线性光耦L817A构成2型误差放大补偿器，根据反馈环路的稳定性原理计算了补偿器参数。逆变器后级为全桥逆变电路，使用STM32F103VC作为主控芯片，对逆变器输出电压进行SPWM调制和电压均值反馈PI控制，同时监测逆变器运行状态、保证系统安全。 3)研究了独立光伏发电系统的能量管理策略。采用由恒流、恒压和浮充组成的三阶段式铅酸蓄电池充电策略，使用电压法结合安时法对蓄电池的荷电常数(SOC)预测，并提出了一套铅酸蓄电池的优化充放电策略。说明了本文光伏系统总体框架，阐述了控制系统的状态和状态切换流程图。最后，使用Matlab\Simulink仿真和实验手段，验证了最大功率点跟踪算法切实可靠；对逆变器输出电压波形和整机效率进行测试，逆变器输出优秀正弦波，效率峰值达88%；通过蓄电池充放电测试，验证了能量管理系统能确保光伏发电系统正常工作。
[Abstract]:In the 21st century, the energy shortage and environmental pollution in the world become more and more serious. The new energy, represented by wind energy and solar energy, has been paid more attention to by the world because of its clean and sustainable characteristics. Independent photovoltaic systems are usually designed to provide power in remote areas without grid coverage, and have a wide range of applications. This paper mainly studies the design and optimization of independent photovoltaic power generation system. The specific work is as follows: 1) under the condition of local shadow, the output power voltage curve of photovoltaic array is multi-peak instead of single peak. The conventional maximum power point tracking strategy lacks the ability of global optimization and is often trapped in local peak value, resulting in large power loss. By analyzing the output characteristic curve of photovoltaic array under local shadow condition, a maximum power point tracking strategy based on auxiliary line, combined with current control and disturbance observation method, is proposed in this paper. 2) A 600W high frequency photovoltaic inverter with rated output power is designed. The inverter has the characteristics of wide input voltage, high conversion efficiency, safety and stability. The forward boost DC of the inverter adopts push-pull topology, PWM chip SG3525 as the control core, TL431 and linear optical coupling L817A as the second type error amplifier compensator. The parameters of the compensator are calculated according to the stability principle of the feedback loop. The inverter is a full-bridge inverter circuit with STM32F103VC as the main control chip. The output voltage of the inverter is controlled by SPWM modulation and voltage mean feedback Pi control. At the same time, the operation state of the inverter is monitored to ensure the safety of the system. 3) the energy management strategy of independent photovoltaic system is studied. A three-stage lead-acid battery charging strategy consisting of constant current, constant voltage and floating charge was adopted. The charge constant of the battery was predicted by voltage method combined with amperage method, and a set of optimal charging and discharging strategies for lead-acid battery was put forward. The general frame of the photovoltaic system is explained, and the flow chart of the state and state switching of the control system is described. Finally, the maximum power point tracking algorithm is verified by Matlab\ Simulink simulation and experiment, the output voltage waveform of inverter and the efficiency of the whole machine are tested, and the inverter outputs excellent sine wave. The energy management system can ensure the normal operation of photovoltaic power generation system through battery charge and discharge test.
【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM615

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