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微型投影机自由曲面LED聚光器的设计 总被引:2,自引:1,他引:1
为提高LED微型投影机中光学引擎的效率和结构紧凑性,研究了自由曲面LED聚光器结构和工作原理,设计了含有折射和反射自由曲面的LED聚光器。采用非成像理论和同时多表面设计方法,计算并获得了聚光器折射和反射两个自由曲面在子午截面内的各点坐标,利用聚光器的旋转对称性得到了其在三维空间内的面形数据。设计结果的光学建模仿真分析表明:所得聚光器能够有效地收集大功率LED光源的能量,并将光束发散角控制在12°内,其光能收集率达到71%。与采用反射式聚光器的设计方案相比,光能收集率提高了20%,而体积则下降了70%,有效地提高了光学引擎的效率和紧凑性。本项设计对LED微型投影仪的小型化具有指导和借鉴作用。 相似文献
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本文描述了一种采用全息反射元件的分段谱光伏打聚光器,系统的转换效率可高于26%。分析了聚光器的特性并给出了全息元件的设计参数和制作方法。 相似文献
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《机械科学与技术》2014,(11):1665-1671
以25 kW碟式光热太阳能发电系统聚光器为对象,建立其有限元模型,基于谐波叠加理论编制Matlab程序得到的脉动风载荷时程开展聚光器风振响应研究。得到了聚光器不同工况下关键节点的统计特征和位移风振系数,给出了部分节点的响应时程数据且对位移时程进行了功率谱分析。结果表明:聚光器在极限风载荷的作用下以强迫振动为主,且在基频处有轻微的共振;聚光器最不利的工况为90°-60°,安全避风工况为-90°-90°,最不利工况下各关键节点的整体位移风振系数为2.4;聚光器结构在极限风载荷作用下处于弹性变形阶段,但曲面固镜壳振动强烈,对于反射镜面的安全性有待于进一步的研究。 相似文献
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多截面形状要求的广义旋转曲面 总被引:1,自引:0,他引:1
旋转曲面在计算机辅助设计中有比较重要的作用 ,很多种类的曲面可以看作由曲线旋转而成 ,传统的旋转曲面在生成的过程中 ,母线的形状不发生变形 ,这样就大大地限制了旋转曲面的应用范围。因此 ,本文对旋转曲面的概念做了进一步的拓宽 ,使母线在旋转运动的过程中能够按照设计的要求发生一定的变形 ,这样就拓宽了其应用范围。曲线在发生变形前后一般要求其形状变化不大 ,本文根据自由曲线能量的概念 ,提出了变形应该使位移曲线的能量最小的假设 ,根据该假设 ,推出了相应的计算公式 ,经过实际计算表明该假设是比较合理的。最后 ,根据本文提出的方法 ,给出了一个有多个截面形状要求的广义旋转曲面造型的例子。 相似文献
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Design of Reflective Concentrator Model with Application for Concentrator Photovoltaic System 总被引:2,自引:0,他引:2
SU Zhongyuan ZHANG Yaoming JIA Minping SUN Liguo XU Feiyun WANG Jun School of Energy & Environment Southeast University Nanjing China School of Mechanical Engineering China Received February revised January accepted June published electronically November 《机械工程学报(英文版)》2011,(6):1007-1012
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. 相似文献
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可横向分光的大接收角非成像式聚光系统 总被引:3,自引:2,他引:1
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,会浪费很多能量.针对这种弊病,对横向非成像光学系统进行了研究,设计了两套接收角分别为6°和10°,聚光比分别为30和20,电池接收面积均为1 cm×1 cm,并能分光的聚光光学系统.设计结果表明,这些系统的光学效率在接收角范围内均大于90%.该类系统拓宽了太阳光谱的吸收范围,降低了对跟踪系统的要求,与高效太阳电池相结合,可制成高效、便携式、非跟踪太阳电池组件,为野外或战场上应用的技术装备提供电源,从而改善它们的灵活性、耐受性和有效性. 相似文献
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文章以乾安县气象局太阳能发电示范基地为例,介绍了太阳能光伏发电的总体设计思想和系统组成;阐述了采用多晶硅、单晶硅等多种材料,并以固定式、单跟踪式、全跟踪式多种发电方式的太阳能光伏发电试验,分析了光伏发电的社会效益和经济效益。 相似文献
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Navas J Alcántara R Fernández-Lorenzo C Martiín-Calleja J 《The Review of scientific instruments》2012,83(4):043102
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. 相似文献
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通过对LD31铝合金钎焊性的分析 ,着重研究了LD31铝合金三维冷凝器钎焊材料的选择。试验结果表明 ,LD31铝合金三维冷凝器采用气保护炉中钎焊 ,在适配的钎焊材料和合理的钎焊工艺下 ,可获得致密、良好的钎焊接头 相似文献
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秦天像 《工业仪表与自动化装置》2014,(4):83-86
由于太阳位置随时间而变化,使光伏发电系统的太阳能电池阵列受光照强度不稳定,从而降低了光伏电池的效率,因此,设计太阳自动跟踪器是提高光伏发电系统工作效率的有效措施。该文针对已有的光伏跟踪控制方法的缺陷与不足,考虑到执行电机在转动时间内对太阳位置角度的变化与跟踪误差范围的预测与控制,提出了一种采用PLC的跟踪控制方法,并通过理论分析与Matlab/Simulink仿真结果验证了其可行性,具有很高的推广应用价值。 相似文献
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N. A. Pakhanov V. M. Andreev M. Z. Shvarts O. P. Pchelyakov 《Optoelectronics, Instrumentation and Data Processing》2018,54(2):187-202
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. 相似文献
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太阳光线与光伏电板垂直时,光伏电板发电效率最高.设计光伏跟踪系统,能有效提高光伏电板发电效率.本文对现有的光伏跟踪系统进行对比研究,从经济性角度分析现有光伏跟踪系统可行性,为先伏产业化中跟踪系统选择提供参考. 相似文献