太阳能制冷技术的特点与现状

太阳能制冷具有环保节能的优点．介绍了各种太阳能制冷技术的原理、特点及存在问题,指出提高太阳能的利用效率和降低成本是其实用化的关键所在。     

主动式太阳房的应用技术

太阳能建筑是当前人居环境科学领域的研究热点之一，本文阐述了太阳能采暖和供家用热水系统的循环原理，给出了系统各部件的理论计算公式，介绍了国外主动式太阳房的应用实例，并分析了主动式太阳房在我国应用的可能性。     

太阳能集中热水系统组合最优化研究

对太阳能热水系统热水成本的组成进行分析,并以呼和浩特市一座小区为例,基于流量计量法与太阳能保证率,计算了系统热水成本费用;对比了不同系统组合的热水单价,使其辅助热源的选定更趋于合理化、人性化,从而推动太阳能集中热水系统组合在呼和浩特市乃至内蒙古地区的优化应用。     

Net-Zero Energy Building Enhancement for a Leadership in Energy and Environmental Design Platinum Educational Facility

In the United States, university buildings use 17% of total non-residential building energy per year. According to the NREL （National Renewable Energy Laboratory）, the average lifecycle of a building in a university is 42 years with an EUI （energy use intensity） of 23 kWh/m^2/y. Current building and energy codes limit the EUI to 16 kWh/m^2/y for new school buildings; this benchmark can vary depending on climate, occupancy, and other contextual factors. Although the LEED （leadership in energy and environmental design） system provides a set of guidelines to rate sustainable buildings, studies have shown that 28%-35% of the educational LEED-rated buildings use more energy than their conventional counterparts. This paper examines the issues specific to a LEED-rated design addition to an existing university building. The forum, a lecture hall expansion of to an existing building at the University of Kansas, has been proposed as environmentally friendly and energy-efficient building addition. Comfort and health aspects have been considered in the design in order to obtain LEED platinum certificate. The forum＇s energy performance strategies include a double-skin facade to reduce energy consumption and PV （photovoltaic） panels to generate onsite energy. This study considers various scenarios to meet NZEB （net-zero energy building） criteria and maximize energy savings. The feasibility of NZE criteria is evaluated for： （a） seasonal comparison; （b） facility occupancy; （c） PV panels＇ addition in relation to double skin facade. The results of NZEB approach are compared to LEED platinum requirements, based on Rol （return on investment） and PV panel＇s efficiency for this specific educational building.     

An analytical and experimental comparison of orthotropic sandwich panels using the Hydromat Test System

A new two-dimensional test system, called the Hydromat Test System, simulates the hydrostatic and hydrodynamic loading conditions which are often present in actual sandwich structures, such as marine hulls. The test fixture uses a square 24 inch×24 inch panel sample which is simply supported all around and has a distributed load provided by a water-filled bladder.

In this study, the Hydromat Test System has been used to obtain data on sandwich panels with orthotropic face sheets and isotropic cores. This data has been compared to analytical expressions for the deflection and the in-plane strains based on small deflection sandwich panel theory. The engineering constants needed for the analytical solution were obtained from characterization tests of the face sheet materials. Core shear properties were obtained experimentally using two different ASTM standards. Four panels, with two different core materials and two different face sheets, were tested. Face sheet properties varied from slightly orthotropic (plane weave) to highly orthotropic (unidirectional), with an axial to transverse tensile moduli ratio of 1.2 and 3.9, respectively. The cores were closed cell foams with both a low and a high shear stiffness.

The analytically obtained center panel deflection varied from 1 to 10% of that obtained by experiment. Most of the analytical tensile strains were less than 10% different from the measured ones. Both experimental deflection and strain data are in excellent agreement with the small deflection theory. It was concluded that the Hydromat Test System provides predictable and repeatable boundary conditions and loading mechanism and is a suitable method for testing soft cored, highly orthotropic sandwich panels.     

GaAs太阳电池帽层腐蚀研究--GaAs/AlGaAs薄膜体系的选择性腐蚀

由ｐ＋－ＧａＡｓ帽层和ｐ－ＡｌｘＧａ１－ｘＡｓ（ｘ＝０·８—０．９）窗口层构成的异质薄膜体系是ＧａＡｓ太阳电池器件中的常规结构。对该异质结构的只腐蚀ＧａＡｓ而不腐蚀ＡｌＧａＡｓ的选择性腐蚀工艺是ＧａＡｓ太阳电池制备过程中的一道关键工序。针对传统腐蚀工艺中出现的腐蚀后露出的ＡｌＧａＡｓ表面呈现彩色的问题,从改进腐蚀液配方角度,围绕通常采用的氨水－双氧水（ＮＨ４ＯＨ－Ｈ２Ｏ２）腐蚀液体系,对该问题作了深入细致的专门研究,并与柠檬酸－双氧水（Ｃ６Ｈ８Ｏ７－Ｈ２Ｏ２）和柠檬酸－柠檬酸钾－双氧水（Ｃ６Ｈ８Ｏ７－Ｋ３Ｃ６Ｈ５Ｏ７－Ｈ２Ｏ２）腐蚀液体系作对比,最终得到了较满意的氨水－双氧水－磷酸（ＮＨ４ＯＨ－Ｈ２Ｏ２－Ｈ３ＰＯ４）新腐蚀液体系。这种腐蚀液体系不仅可在较宽的溶液浓度范围内实现对高Ａｌ组分ＧａＡｓ／ＡｌＧａＡｓ异质结构的选择性腐蚀,而且也不会对露出的ＡｌＧａＡｓ外观产生明显影响     

太阳能电动车碳纤维车身成型方法

在1/5太阳能电动车碳纤维车身模具与模型已经制作成功的基础上,总结了碳纤维车身成型的经验和方法,研究了车身成型模具的设计、制作工艺及其碳纤维车身的成型过程。针对车体模型的质量控制、模具切片方法选择等关键问题进行分析讨论,完成了车身模具与模型的设计和制作。     

Understanding of the annealing temperature impact on ion implanted bifacial n‐type solar cells to reach 20.3% efficiency

Ion implantation has the advantage of being a unidirectional doping technique. Unlike gaseous diffusion, this characteristic highlights strong possibilities to simplify solar cell process flows. The use of ion implantation doping for n‐type PERT bifacial solar cells is a promising process, but mainly if it goes with a unique co‐annealing step to activate both dopants and to grow a SiO₂ passivation layer. To develop this process and our SONIA cells, we studied the impact of the annealing temperature and that of the passivation layers on the electrical quality of the implanted B‐emitter and P‐BSF. A high annealing temperature (above 1000 °C) was necessary to fully activate the boron atoms and to anneal the implantation damages. Low J_0BSF (BSF contribution to the saturation current density) of 180 fA/cm² was reached at this high temperature with the best SiO₂ passivation layer. An average efficiency of 19.7% was reached using this simplified process flow (“co‐anneal process”) on large area (239 cm²) Cz solar cells. The efficiency was limited by a low FF, probably due to contaminations by metallization pastes. Improved performances were achieved in the case of a “separated anneals” process where the P‐BSF is activated at a lower temperature range. An average efficiency of 20.2% was obtained in this case, with a 20.3% certified cell. Copyright © 2014 John Wiley & Sons, Ltd.     

基于ADAMS的太阳电池阵动力学模拟参数化建模系统

根据太阳电池阵的特点和ADAMS软件二次开发功能,制定了太阳电池阵动力学特性模拟系统的程序构架.太阳电池阵由驱动机构、摇臂架、帆板、连接铰、锁定机构和同步机构组成.编制了相应的软件模块,包括主界面、初始化模块、间隙铰模块、构件模块和机构模块,初步实现了对太阳能帆板动力学模拟的参数化建模,采用编制的模拟系统对帆板展开机构...     

一种基于ON/OFF控制的太阳能电池MPPT控制器

在太阳能光伏发电系统中,为了降低系统造价并提高对太阳能的利用率,一般需要实现最大功率点跟踪.本文通过分析太阳能电池的功率-电流(P-I)特性曲线,提出了一种新的利用硬件电路来实现最大功率点跟踪的方法.与以往跟踪方法不同,该方法简单实用,仅需采样太阳能电池的输出电流和电压,通过比较其输出电流的变化率和输出功率的变化率,基于ON/OFF控制太阳能电池输出端电容的充放电,使其输出电流(或电压)达到最大功率点电流(或电压),实现了真正意义上的MPPT.以Buck DC/DC变换器为例,通过仿真和实验验证了理论分析的正确性.