光伏发电效率检测及跟踪系统的实验研究

发布时间：2018-06-10 18:56

本文选题：光伏发电效率 + MPPT　；参考：《广西大学》2014年硕士论文

【摘要】：随着环境污染和能源危机等问题的日益严峻,人们把焦点放在再生洁净能源的开发和利用上。太阳能极其清洁,无污染,取不完,用不尽,得到各国的青睐。尽管光伏发电技术已日渐成熟,但光伏发电成本较高、效率偏低等问题依然存在。本文针对提高光伏发电效率开展研究。首先根据光伏电池的等效电路,在Simulink中搭建仿真模型,研究温度和光强对光伏电池输出特性的影响。为使光伏电池在温度和光强变化时能很快跟踪到最大功率点,提高光伏能量的转换效率,对常见的MPPT方法的原理进行比较并建立仿真模型。在此基础上提出一种改进的MPPT方法,与常规MPPT法进行比较,结果表明改进后的控制算法跟踪精度较高,稳定性较好。光伏组件的发电能力与其安装的朝向有关,合理选择倾角和方位角能提高光伏组件的发电效率。为此,本文设计并研制出一套光伏发电效率检测系统,使用MFC开发工具设计软件监控界面。该系统由12块光伏组件组成,采用电容充放电法,对光伏组件的伏安特性进行扫描并寻找到该时刻最大功率点,定时采集光伏组件最大功率点电压、电流、功率等数据,并根据上位机的指令传送数据并写入数据库。对数据库中保存的近一年的数据进行分析,比较光伏组件的实时发电功率、日总发电量和月总发电量,给出南宁地区光伏阵列最佳的安装倾角和方位角建议。本课题还进行了太阳能双轴跟踪系统的软硬件设计,系统硬件主要由芯片电源、光电传感器、风速传感和限位开关、电机驱动电路组成；软件主要包括主程序、系统初始化、光电跟踪子程序等部分。利用太阳能双轴跟踪系统进行南宁地区光伏发电实验,得到有关的数据并与固定式光伏系统(正南22°倾角)进行比较。实验结果表明,所设计的双轴跟踪系统的发电效率比固定式系统提高了近35%,对实际工程应用有一定的参考价值。
[Abstract]:With the increasing severity of environmental pollution and energy crisis, people focus on the development and utilization of renewable and clean energy. Solar energy is extremely clean, pollution-free, endless, inexhaustible, favored by all countries. Although photovoltaic power generation technology is becoming more and more mature, there are still some problems such as high cost and low efficiency of photovoltaic power generation. Firstly, according to the equivalent circuit of photovoltaic cells, a simulation model is built in Simulink to study the effect of temperature and light intensity on the output characteristics of photovoltaic cells. In order to track the maximum power point quickly and improve the efficiency of photovoltaic energy conversion, the principle of common MPPT method is compared and the simulation model is established. On this basis, an improved MPPT method is proposed, which is compared with the conventional MPPT method. The results show that the improved control algorithm has higher tracking accuracy and better stability. Reasonable selection of inclination angle and azimuth angle can improve the efficiency of photovoltaic module. Therefore, this paper designs and develops a photovoltaic generation efficiency detection system, and uses MFC development tools to design the software monitoring interface. The system is composed of 12 photovoltaic modules. The volt-ampere characteristic of the PV module is scanned by capacitive charge-discharge method and the maximum power point at this time is found. The maximum power point voltage, current and power of the photovoltaic module are collected at the same time. And according to the instructions of the host computer to transmit data and write to the database. The data stored in the database for nearly one year are analyzed, and the real time generation power, the daily total power generation and the monthly total power generation of the photovoltaic module are compared. The optimal installation inclination angle and azimuth angle of photovoltaic array in Nanning area are given. The software and hardware design of solar biaxial tracking system is also carried out. The hardware of the system is mainly composed of chip power supply, photoelectric sensor, wind speed sensor and limit switch. The main software includes main program, system initialization, photoelectric tracking subroutine and so on. The solar biaxial tracking system is used to carry out photovoltaic power generation experiment in Nanning area. The relevant data are obtained and compared with the fixed photovoltaic system (22 掳inclination to the south). The experimental results show that the power generation efficiency of the designed biaxial tracking system is nearly 35% higher than that of the fixed system, which has some reference value for practical engineering application.
【学位授予单位】：广西大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM615

【参考文献】