高精度双轴太阳跟踪控制器设计

结合聚光式光伏发电对太阳跟踪装置的应用需求,设计了基于DSP与CPLD的高精度双轴太阳跟踪控制器.设计以太阳位置计算的方法为主要跟踪控制方式,采用CCD传感器对太阳跟踪角度偏差检测自动定位和校准.结合光电定位校准开关,可以消除较大的机械积累误差,跟踪精度高.根据太阳高度自动调整启动返回时闻,可以最大限度地获得更多的光能...     

聚光型光伏发电的太阳能定位和跟踪系统

在资源紧缺的今天,太阳能以它恒定的来源和高强的辐射能量,日渐成为资源利用的首要选择。聚光型光伏发电的基本原理是采用带有菲尼尔透镜的太阳能电池板,利用图像采集传感器,拍摄参照物的太阳影子长度,并以与垂直投影做出的比较测出太阳的偏转角度,通过高速控制芯片,根据对采集信息的分析,控制传动机构调节太阳能电池板的偏转角度,实现对太阳的定位和跟踪,从而实现太阳能的高效采集。     

基于STM32的太阳能双轴跟踪控制系统

利用太阳能跟踪支架,使太阳能电池始终能被太阳光直射以提高发电效率,降低太阳能电池板的尺寸并节省成本。文中设计以STM32F103ZET6为控制核心的太阳支架双轴跟踪控制系统,系统根据支架所在地的经纬度与时间,计算出蜗轮蜗杆与推杆的相应位置,改变支架的高度角与方位角,实现双轴跟踪;并且利用照度传感器与风速传感器,使支架能适应不同天气;加入软件自动修复等技术,降低系统功耗、提高系统稳定性。该产品在实际应用中能较好地满足精度与稳定性要求。     

高精度太阳能跟踪控制器

针对目前采用的传统太阳能跟踪控制器传感器形式单一、抗干扰性差、跟踪精度不高等问题,设计了一种基于可编程逻辑控制器(Programmable Logic Controller,PLC)的太阳能跟踪控制器系统。该系统将固定轨迹粗略跟踪方式与光电传感器精确跟踪方式有效地结合起来,并重点将光电传感器加以改进,从而有效地提高了太阳能利用率。由伺服电机作为执行机构控制太阳能板对太阳位置的跟踪,可以实现对太阳高度角和方位角的双自由度跟踪,使太阳能跟踪装置始终正对着太阳光线位置。通过对比实验表明,该跟踪控制器可以达到较高的跟踪精度。     

关于光伏发电系统跟踪太阳聚光发电优化控制

针对跟踪太阳聚光发电对跟踪太阳精度要求高、机械惯性大、动力传导存在死区,改进设计一种适用于复杂环境的高精度太阳传感器,通过差分形式对太阳位置进行粗略和精密检测,建立了跟踪太阳聚光发电系统动力部分的数学模型,提出基于模糊控制的跟踪太阳聚光发电优化控制策略,通过仿真和现场应用结果表明,设计的太阳传感器能够适应强光和弱光环境,检测精度优于 0.3°,提出的控制策略能够实现连续高精度跟踪太阳,提升了发电效率。     

关于光伏发电系统跟踪太阳聚光发电优化控制

针对跟踪太阳聚光发电对跟踪太阳精度要求高、机械惯性大、动力传导存在死区，改进设计一种适用于复杂环境的高精度太阳传感器，通过差分形式对太阳位置进行粗略和精密检测，建立了跟踪太阳聚光发电系统动力部分的数学模型，提出基于模糊控制的跟踪太阳聚光发电优化控制策略。通过仿真和现场应用结果表明，设计的太阳传感器能够适应强光和弱光环境，检测精度优于 0.3°，提出的控制策略能够实现连续高精度跟踪太阳，提升了发电效率。     

聚光太阳能系统与项目开发管理工具

介绍了聚光太阳能系统的应用前景、系统组成、关键技术和项目的开发管理工具。供从事光伏项目管理工作时参考。     

基于PLC的太阳能跟踪控制系统的设计

提出了基于可编程逻辑控制器PLC(Programmable Logic Controller)的太阳能跟踪系统,使太阳能模块能实时跟踪太阳光照,将太阳能利用到最大限度。系统包括硬件和软件两部分,硬件有PLC输入输出端口,信号处理模块,光敏电阻光强法比较电路以及开关电源的设计,软件包括PLC控制程序和监控程序。基于PLC的太阳能跟踪系统可以独立应用于太阳能发电设备,也可以应用于串并联的大型光伏发电系统现场的总线控制,具有非常广阔的前景。     

S7-200PLC在太阳能跟踪控制系统中的应用

太阳能跟踪控制系统是光伏发电实训系统的重要组成部分,阐述了全太阳能跟踪控制系统的组成,以西门子S7-200PLC为核心配置了系统,以STEP 7 MicroWin为开发环境完成了光伏系统中的"逐日"用户程序的开发,并配有监控界面。结果表明,该系统能够实现光伏发电实训系统中太阳能的采集,提高太阳能发电系统的效率。     

基于FPGA的光电跟踪控制系统设计

为了提高光电跟踪控制系统可靠性和实时性,设计了一种基于FPGA的控制系统.该控制系统以一块FPGA芯片为核心,主要完成传感器信号处理,控制算法实现,脉宽调制方波生成,与上位机通信等任务.采用Xilinx公司的ISE7.0平台进行开发,并用层次化和模块化的方式进行设计.实验结果表明这种设计方法使系统以比较低的成本获得了很高的处理速度,从而提高了系统的性能.     

基于单片机的太阳追踪系统的设计

针对固定式太阳能利用装置的光能利用率低,设计一种太阳追踪系统。此系统由单片机智能控制,采用光电传感器检测太阳照射下遮光器的阴影,从而精确定位太阳与太阳能利用装置相对位置,实现太阳能利用装置的全程太阳追踪,使太阳光能最大限度地得到利用。     

Thermal analysis and test for single concentrator solar cells

A thermal model for concentrator solar cells based on energy conservation principles was designed.Under 400X concentration with no cooling aid,the cell temperature would get up to about 1200℃.Metal plates were used as heat sinks for cooling the system,which remarkably reduce the cell temperature.For a fixed concentration ratio,the cell temperature reduced as the heat sink area increased.In order to keep the cell at a constant temperature,the heat sink area needs to increase linearly as a function of the concentration ratio.GaInP/GaAs/Ge triple-junction solar cells were fabricated to verify the model.A cell temperature of 37℃ was measured when using a heat sink at 400X concentratration.     

单体聚光太阳电池的热分析和温度测试

A thermal model for concentrator solar cells based on energy conservation principles was designed. Under 400X concentration with no cooling aid, the cell temperature would get up to about 1200 ？C. Metal plates were used as heat sinks for cooling the system, which remarkably reduce the cell temperature. For a fixed concentration ratio, the cell temperature reduced as the heat sink area increased. In order to keep the cell at a constant temperature, the heat sink area needs to increase linearly as a function of the concentration ratio. GaInP/GaAs/Ge triple-junction solar cells were fabricated to verify the model. A cell temperature of 37 ？C was measured when using a heat sink at 400X concentration.     

空间激光通信单探测器复合跟踪控制技术研究

空间激光通信终端伺服系统是一种高精度的跟踪机构,在扰动条件下,通信系统对跟踪系统的稳定性及精度提出了较高的要求。本文主要介绍了激光通信伺服系统的复合跟踪技术,详细论述了单探测器复合跟踪方式的选择以及激光通信伺服系统的控制流程。最后,在振动平台上进行了粗精复合的激光跟踪实验。实验结果显示,当通信终端系统跟踪最大振动加速度为0.22°/s2的振动平台时,跟踪目标平稳性较好,单独采用粗跟踪时误差为60 μrad,采用粗精复合跟踪时位置误差可以达到2 μrad。实验结果表明,空间激光通信系统中单探测器复合跟踪技术的设计满足了系统跟踪精度的要求,为激光通信控制系统的设计提供了一定的参考。     

High‐irradiance degradation tests on concentrator GaAs solar cells

The present work summarises the results of an experiment of light‐soaking high‐concentrator MOVPE‐grown GaAs solar cells under monochromatic light (808 nm). The irradiance level was set so that the short‐circuit current obtained was 1100 times that produced with the AM1ċ5D spectrum at 1 kW/m². This test caused no morphological changes in the devices. The main phenomenon discovered has been a slight increase with time of the reverse current I₀₂. This increase is analogous to that observed in similar degradation experiments based on high forward currents. In general, the results of these tests show that the drop in performance is very limited, supporting the idea that concentrator GaAs solar cells are rugged devices, capable of achieving long lifetimes in field operation. Copyright © 2003 John Wiley & Sons, Ltd.     

Design and realization of transparent solar modules based on luminescent solar concentrators integrating nanostructured photonic crystals

Herein, we present a prototype of a photovoltaic module that combines a luminescent solar concentrator integrating one‐dimensional photonic crystals and in‐plane CuInGaSe₂ (CIGS) solar cells. Highly uniform and wide‐area nanostructured multilayers with photonic crystal properties were deposited by a cost‐efficient and scalable liquid processing amenable to large‐scale fabrication. Their role is to both maximize light absorption in the targeted spectral range, determined by the fluorophore employed, and minimize losses caused by emission at angles within the escape cone of the planar concentrator. From a structural perspective, the porous nature of the layers facilitates the integration with the thermoplastic polymers typically used to encapsulate and seal these modules. Judicious design of the module geometry, as well as of the optical properties of the dielectric mirrors employed, allows optimizing light guiding and hence photovoltaic performance while preserving a great deal of transparency. Optimized in‐plane designs like the one herein proposed are of relevance for building integrated photovoltaics, as ease of fabrication, long‐term stability and improved performance are simultaneously achieved. © 2015 The Authors. Progress in Photovoltaics: Research and Applications published by John Wiley & Sons Ltd.     

晶体硅聚光太阳能电池的发射极和前电极优化

The optimizations of the emitter region and the metal grid of a concentrator silicon solar cell are illustrated. The optimizations are done under 1 sun,100 suns and 200 suns using the 2D numerical simulation tool TCAD software.The optimum finger spacing and its range decrease with the increase in sheet resistance and concentration ratio.The processes of the diffusion and oxidization in the manufacture flow of the silicon solar cells were simulated to get a series of typical emitter dopant profiles to optimize.The efficiency of the solar cell under 100 suns and 200 suns increased with the decrease in diffusion temperature and the increase in oxidation temperature and time when the diffusion temperature is lower than or equal to 865℃.The effect of sheet resistance of the emitter on series resistance and the conversion efficiency of the solar cell under concentration was discussed.     

Development of concentrator modules with dome‐shaped Fresnel lenses and triple‐junction concentrator cells

The status of the development of a new concentrator module in Japan is discussed based on three arguments, performance, reliability and cost. We have achieved a 26·6% peak uncorrected efficiency from a 7056 cm² 400 × module with 36 solar cells connected in series, measured in house. The peak uncorrected efficiencies of the same type of the module with 6 solar cells connected in series and 1176 cm² area measured by Fraunhofer ISE and NREL are reported as 27·4% and 24·8% respectively. The peak uncorrected efficiency for a 550× and 5445 cm² module with 20 solar cells connected in series was 28·9% in house. The temperature‐corrected efficiency of the 550 × module under optimal solar irradiation condition was 31·5 ± 1·7%. In terms of performance, the annual power generation is discussed based on a side‐by‐side evaluation against a 14% commercial multicrystalline silicon module. For reliability, some new degradation modes inherent to high concentration III‐V solar cell system are discussed and a 20‐year lifetime under concentrated flux exposure proven. The fail‐safe issues concerning the concentrated sunlight are also discussed. Moreover, the overall scenario for the reduction of material cost is discussed. Copyright © 2005 John Wiley & Sons, Ltd.     

基于单片机的双轴太阳能跟踪系统的设计

为了解决太阳能工程项目中光伏效率不高的问题,设计了双轴太阳能跟踪装置,该系统采用视日轨迹跟踪方案。文中着重分析了双轴跟踪的原理及其系统组成,利用光伏元件和STC89C52单片机实现大范围太阳跟踪,液晶显示屏实时显示最佳接收方位角及温湿度。在光线充足的天气条件下,跟踪装置自动旋转并始终保持太阳光垂直照射在太阳能电池的表面。在阴雨天或夜间等光线不足的条件下系统停止跟踪太阳转动。整个系统不需要任何外部电源供电,实现对太阳的高精度跟踪,并且使系统具有较强的抗干扰和运算能力。     

Thermo-electronic solar power conversion with a parabolic concentrator

We consider the energy dynamics of the power generation from the sun when the solar energy is concentrated on to the emitter of a thermo-electronic converter with the help of a parabolic mirror. We use the modified Richardson-Dushman equation. The emitter cross section is assumed to be exactly equal to the focused area at a height h from the base of the mirror to prevent loss of efficiency. We report the variation of output power with solar insolation, height h, reflectivity of the mirror, and anode temperature, initially assuming that there is no space charge effect. Our methodology allows us to predict the temperature at which the anode must be cooled in order to prevent loss of efficiency of power conversion. Novel ways of tackling the space charge problem have been discussed. The space charge effect is modeled through the introduction of a parameter f (0 < f < 1) in the thermos-electron emission equation. We find that the efficiency of the power conversion depends on solar insolation, height h, apart from radii R of the concentrator aperture and emitter, and the collector material properties. We have also considered solar thermos electronic power conversion by using single atom-layer graphene as an emitter.