大接收角、可横向分光、非成像式聚光系统

以传统聚光系统为基础的聚光电池虽然可以减少电池量,但需要精度高的跟踪装置,同时由于电池的吸收光谱较窄,而太阳光谱却较宽,会有很多能量被浪费。针对这种弊病,对横向非成像光学系统进行了研究,设计了能够实现大角度接收太阳光并分光的聚光光学系统。该系统与高效太阳电池相结合,便会形成高效、便携式、非跟踪太阳电池组件,为那些应用于野外或战场上的技术装备如笔记本电脑、成像、测量、通讯等设备提供电源,从而改善它们的灵活性、耐受性和有效性。     

太阳能供电的飞轮电池系统设计

针对太阳能单轴跟踪机构接收效率低的缺陷,提出了一种基于双轴跟踪机构的飞轮电池系统,介绍了其总体方案和工作原理。分析了全年日出日落时刻和日照时间,得到太阳能板最优初始角。在此基础上,对太阳能双轴跟踪机构进行了具体设计。考虑转子最大应力、一阶共振频率、陀螺效应、磁轴承控制解耦和位移传感器检测精度,对磁悬浮飞轮系统进行了详细设计。根据设计结果加工了一套太阳能供电的飞轮电池系统,并通过太阳光跟踪、飞轮升速和降速发电实验,验证了设计结果的正确性。     

太阳电池测试系统设计

为满足太阳电池生产企业需求,采用长弧脉冲疝灯加光学系统组成太阳模拟器,设计了一种太阳电池组件测试系统,用于测试太阳电池各种参数。测试结果表明,该测试系统的光谱匹配度及辐照不均匀度均达到A等级技术指标要求。     

槽式太阳能集热器单轴太阳跟踪系统的设计

针对抛物槽式太阳能集热器集热在夏天用来做制冷空调,提出了基于南北水平式的太阳自动跟踪系统的设计方案,对该跟踪系统的机械传动系统进行了设计计算及选型,其中自动/手动跟踪太阳高度角和太阳方位角采用蜗杆传动箱方案,而手动转动手轮方案保证太阳入射光线和主光轴方向一致;对该跟踪系统的控制系统进行了控制系统的方案设计,硬件选型及程序编制。实验测试表明,该太阳自动跟踪系统跟踪角的跟踪精度高,抛物槽的聚光比高,集热性能好。     

聚光跟踪光伏光热一体机联动装置的研制

针对聚光器跟踪太阳的准确度对聚光效率影响很大,提出了一种太阳跟踪联动装置。采用两根电动推杆驱动聚光器的方位角传动轴和高度角联动架,实现了多个聚光单元同步跟踪太阳高度角和方位角的变化。经分析跟踪误差并经实验验证,该聚光器跟踪装置运行稳定、传动精度高,聚光效率提高了5%,降低了光伏发电的成本。     

基于光学自由曲面的离轴三反光学系统

为了研制长焦距大视场离轴三反空间光学系统,描述了自由曲面光学数理模型,设计了基于自由曲面的离轴三反光学系统.针对焦距为4500 mm,成像视场角为11°,系统总长与焦距的比值为1/3的光学系统,对比分析了传统离轴三反光学系统和次镜为自由曲面的离轴三反光学系统的关键性能.在提出的光学系统中次镜采用自由曲面设计,提升了光学...     

小型可见光双视场光学系统的研制

基于光学设计基本理论,设计了一种体积小,跟踪范围可以达到整个前半球的可见光双视场光学系统.系统由前部集束系统,中间光路转折系统及后部成像系统3部分组成.集束系统采用望远镜式结构,用于改变光束的口径;光路转折系统采用库德光路,由4片反射镜组成,用于转折光路及扫描;成像系统由长焦成像系统和短焦成像系统组成,分别形成两个视场的像,用于目标识别与跟踪.光学系统焦距分别为60 mm和120 mm,设计传递函数在58 lp/mm处均大于0.5.加工装调后进行了成像试验验证,结果表明,该系统能够同时完成大视场及小视场的图像获取,在可视范围内成像质量满足系统总体要求.     

高能高准直性太阳模拟器设计

设计一种能够同时满足辐照面辐照度达到一个太阳常数和32′张角的太阳模拟器。利用理论计算和光学软件仿真相结合的设计方式,对聚光系统、积分器和准直系统分别进行设计与优化,并提出一种新的氙灯建模方式,最后利用lighttools对整体光学系统进行仿真分析,获得了各部件在光学系统中的最佳位置,使整个光学系统达到较高的能量利用率和辐照均匀性。     

光伏发电伺服跟踪控制系统的设计与应用

太阳能板接收能量的效率直接影响光伏并网发电量。为提高接收效率,利用dSPACE DS1104 R＆D控制器板设计了一种伺服跟踪系统,该系统结合了光电跟踪和视日跟踪两种方法,实现了对日光的垂直跟踪。dSPACE和Matlab／Simulink之间的无缝连接使得开发过程快速高效,实验结果验证了系统的有效性。     

线性菲涅尔聚光控制系统设计

设计了针对线性菲涅尔聚光集热单元的控制系统,自动接收GPS信号计算太阳位置及太阳倾角,采用太阳视日运动轨迹跟踪方法,比较当前倾角与理论倾角的偏差,结合极限角度,驱动反射镜自动追踪太阳位置。设计了性能可靠的电机驱动电路和抗干扰能力强且符合ESD防护的RS485及RS232通信电路。经验证,控制系统具有稳定、高效、精确的优点,有助于提升线性菲涅尔系统的集热效率。     

基于DSP的新型太阳方位跟踪系统

为了提高太阳方位跟踪精度,降低光伏发电系统的成本,利用光伏电池旋转产生的短路电流是交变电流的这一特点,通过离散傅里叶变换（DFT）求解交变电流的初相位,计算太阳的高度角和方位角,实现了对太阳方位的自动跟踪。并依此方法设计出了一套基于数字信号处理器（DSP）的新型太阳方位跟踪系统。实验结果表明,该系统能实现太阳光大范围内检测,并迅速跟踪,可避免多块光敏元件的不一致性所带来的问题,有效地提高了跟踪系统的精确性,可望在太阳能光伏发电工程中得到应用。     

Instrumentation for accelerated life tests of concentrator solar cells

Concentrator photovoltaic is an emergent technology that may be a good economical and efficient alternative for the generation of electricity at a competitive cost. However, the reliability of these new solar cells and systems is still an open issue due to the high-irradiation level they are subjected to as well as the electrical and thermal stresses that they are expected to endure. To evaluate the reliability in a short period of time, accelerated aging tests are essential. Thermal aging tests for concentrator photovoltaic solar cells and systems under illumination are not available because no technical solution to the problem of reaching the working concentration inside a climatic chamber has been available. This work presents an automatic instrumentation system that overcomes the aforementioned limitation. Working conditions have been simulated by forward biasing the solar cells to the current they would handle at the working concentration (in this case, 700 and 1050 times the irradiance at one standard sun). The instrumentation system has been deployed for more than 10?000 h in a thermal aging test for III-V concentrator solar cells, in which the generated power evolution at different temperatures has been monitored. As a result of this test, the acceleration factor has been calculated, thus allowing for the degradation evolution at any temperature in addition to normal working conditions to be obtained.     

太阳能水下航行器光伏系统MPPT控制仿真研究

通过光伏电池的简化模型,研究了光伏电池的输出特性,并分析了BUCK斩波电路寻找最大功率点的实现原理.提出了变步长扰动MPPT策略,并在Matlab仿真环境中开发了带有此策略的仿真模型.利用此模型进行计算机仿真,结果表明,太阳能水下航行器光伏系统变步长MPPT控制,能够准确地跟踪太阳能电池的最大功率点,提高了太阳能电池利用效率.     

On-line thermal dependence study of the main solar cell electrical photoconversion parameters using low thermal emission lamps

This paper presents a non-conventional methodology and an instrumental system to measure the effect of temperature on the photovoltaic properties of solar cells. The system enables the direct measurement of the evolution of open-circuit voltage and short-circuit current intensity in relation to a continuously decreasing temperature. The system uses a high-intensity white light-emitting diode light source with low emissions of radiation in the infrared region of the electromagnetic spectrum, resulting in a reduced heating of the photovoltaic devices by the irradiation source itself. To check the goodness of the system and the methodology designed, several measurements were performed with monocrystalline silicon solar cells, dye-sensitized solar cells, and thin-film amorphous silicon solar cells, showing similar tendencies to those reported in the literature.     

Experimental analysis and computer simulation of a methodology for laser focusing in the solar cell characterization by laser beam induced current

This paper presents a quick methodology for focusing a laser beam on a photoactive surface based on performing a single line scan while simultaneously modifying the laser's position over the surface and the distance between the focusing lens and the active surface. The methodology was tested using the computer simulation technique. Several configurations were computer simulated by programming different experimental situations to discover the situations in which this focusing methodology would provide optimum results. The conclusions obtained from computer simulation methodology were checked by means of experimental tests using several solar cells, such as a thin-film amorphous silicon solar cell, a monocrystalline silicon solar cell, and a polycrystalline silicon solar cell. From the tests performed, we concluded that optimum focusing is achieved in systems in which the laser beam induced current signal generated by the photoactive surface has no large heterogeneities (e.g., fingers or grain boundaries), artefacts, or defects. Thus, the best results are achieved in systems where the surface of the photovoltaic device has a certain degree of homogeneity.     

Design of Reflective Concentrator Model with Application for Concentrator Photovoltaic System

The nonuniform irradiation in the standard photovoltaic(PV) cells causes their relatively high series resistance,which results in a considerably lowered efficiency of PV cells.Currently the concentrator of uniform irradiation designed for concentrator photovoltaic is rare in China and lack sufficient theoretical research.In this paper,a systematic research on the solar reflective concentrator is conducted.A novel structure for a solar reflective concentrator is designed with the application of a flat mirror matrix to concentrate the sunlight for concentrator photovoltaic(CPV) systems.Sunlight beams are focused through the reflection of the mirror array on the solar cell to generate electricity.The concentrator is capable of producing much more uniform sunlight with a certain concentration ratio.The design scheme includes laying out the flat mirrors,optimizing the optical pathway and the parameters of each mirror.The prototype of the CPV system was installed at Nanjing,China.In the configuration of the prototype,it is composed of 24 pieces parallelogram flat mirrors,which are arranged into a total reflective array of 5 rows and 5 columns.In comparison with the parabolic trough concentrator,the experimental measurements verify such design has high efficiency.The concentrator model of a flat mirror matrix and the proposed new design method will lay a solid foundation for designing the concentrator of uniform irradiation.     

一种适用于CPV的太阳模拟器的光学结构与分析

太阳模拟器是聚光光伏(CPV)领域内对电池片、组件及系统进行在线检测的一种必不可少的光源设备,其要求辐照度大于800 W/m2,准直角度小,辐照度均匀,光谱接近AM1.5。要同时达到这些指标有一定的难度。通过分析实现既辐照均匀又辐照准直的太阳模拟器需要克服的因素,提出了一种太阳模拟器结构方案以满足上述要求。同时,配比不同焦距的准直透镜还可实现辐照面积可调。利用ZEMAX软件对该结构进行了仿真,验证了该方案的实现效果。     

State-of-the-art Architectures and Technologies of High-Efficiency Solar Cells Based on III–V Heterostructures for Space and Terrestrial Applications

Multi-junction solar cells based on III–V compounds are the most efficient converters of solar energy to electricity and are widely used in space solar arrays and terrestrial photovoltaic modules with sunlight concentrators. All modern high-efficiency III–V solar cells are based on the long-developed triple-junction III–V GaInP/GaInAs/Ge heterostructure and have an almost limiting efficiency for a given architecture — 30 and 41.6% for space and terrestrial concentrated radiations, respectively. Currently, an increase in efficiency is achieved by converting from the 3-junction to the more efficient 4-, 5-, and even 6-junction III–V architectures: growth technologies and methods of post-growth treatment of structures have been developed, new materials with optimal bandgaps have been designed, and crystallographic parameters have been improved. In this review, we consider recent achievements and prospects for the main directions of research and improvement of architectures, technologies, and materials used in laboratories to develop solar cells with the best conversion efficiency: 35.8% for space, 38.8% for terrestrial, and 46.1% for concentrated sunlight. It is supposed that by 2020, the efficiency will approach 40% for direct space radiation and 50% for concentrated terrestrial solar radiation. This review considers the architecture and technologies of solar cells with record-breaking efficiency for terrestrial and space applications. It should be noted that in terrestrial power plants, the use of III–V SCs is economically advantageous in systems with sunlight concentrators.     

封装标准太阳电池性能及其与国际标准一致性的评价

基于国际电工委员会(IEC)国际标准分析了引起标准太阳电池量值传递误差的因素及其与国际标准的一致性。随机选取我国市场上销售的6种封装标准太阳电池,测量了它们的温度特性、光谱响应特性和表面反射特性。结果表明:电池的封装结构影响它们的冷却效果及温度的正确测量,从而导致温度和短路电流的不稳定性,其变异系数最高可达0.12%和0.04%。另外,有、无偏置光条件下的光谱响应特性均反映其光电流的光照强度线性特性,这里定义用光谱拟合度来衡量各封装太阳电池的光谱响应特性。采用改变入射角测量短路电流的方法分析了表面光反射对短路电流的影响,利用余弦函数拟合确定了由表面反射光所引起的短路电流的误差可达0.21%。本文的研究成果对光伏行业正确制造、选择和使用标准太阳电池具有指导作用。     

基于MCS-51的太阳能量板自动追日系统的设计

通过设计一种基于51单片机的高效自动追日控制板,提高了太阳能量板的光伏转化效率,同时实现光伏电池的自动管理和维护,在控制板的设计中加入了RS485和CAN总线,使太阳能发电的阵列化成为了可能,从而提高了转化效率,降低了能耗。