太阳能电池工作特性户外监测系统研究

根据对光伏系统户外监测的需求,本文提出了结合恒定电压法与基于电阻矩阵增量导纳法的I-V曲线扫描算法,并阐述了样条插值曲线的重构方案。对上述算法的误差来源及复原曲线进行了分析,并根据具体的应用环境给出了该算法的具体实现。在此基础上给出了监测系统的架构设计及应用方法。依据该算法对实际监测的太阳能电池参数的准确性进行了仿真与实验。结果表明,本方案简便易行、扩展性好且具有较高的测量精度,可为户外光伏系统工作特性监测领域的设计提供一种较有竞争力的技术方案。     

分布式大规模交通网络实时模拟系统

大规模交通网络的研究目前已经成为一个热点研究领域,大规模交通网络的实时模拟为交通规划和交通控制提供了一个研究的平台和基础,因此模拟系统的设计与实现具有相当重要的意义。由于网络规模以及汽车数量的原因,使用单台计算机不可能满足模拟整个城市规模交通网络的需求,必须采用分布式模拟系统。文章研究并设计了分布式大规模交通网络模拟系统,具体试验表明完全可以满足实时模拟的需要。     

Managing Risks in Distributed Software Projects: An Integrative Framework

Software projects are increasingly geographically distributed with limited face-to-face interaction between participants. These projects face particular challenges that need careful managerial attention. While risk management has been adopted with success to address other challenges within software development, there are currently no frameworks available for managing risks related to geographical distribution. On this background, we systematically review the literature on geographically distributed software projects. Based on the review, we synthesize what we know about risks and risk resolution techniques into an integrative framework for managing risks in distributed contexts. Subsequent implementation of a Web-based tool helped us refine the framework based on empirical evaluation of its practical usefulness. We conclude by discussing implications for both research and practice.     

光伏产业面临的研发挑战

尽管晶体硅太阳能电池继续主宰着全球光伏市场,但由于不断增加的价格压力,要获得持续性的成长,它们还面临许多挑战.研发人员正努力开发创新的方法应对这些挑战.     

光风能混合双动力智能小车设计说明

本文着重分析探讨研究微型风力-太阳能光伏互补发电系统.风能和太阳能具有天然互补性,因此风能与光伏混合双动力,给智能小车供电,可靠性高,同时合理的配置储能装置的容量,效率高.我们希望通过深入研究,为实现新能源综合利用提供一种研究思路与设计方法,以期能为以后的实际工作起到一定的借鉴作用.     

分布式系统中的冲突算法

分布式系统是为解决单个问题而紧密结合在一起工作的多处理机的集合。这些处理机连接在一起以实现对不同资源的共享。为了保证所共享资源的正确性和安全性，合适的冲突算法的设计在系统架构中起着至关紧要的作用。本文将分析常见冲突算法，并给出一些关键的实现步骤。     

The Solarex approach to expanding the PV business

Solarex was founded in 1973 to develop photovoltaic products for terrestrial applications. Over the last 24 years, the company has moved from single-crystal silicon technology to polycrystalline silicon and has also developed both single-junction and multi-junction amorphous silicon solar cell technology. Solarex is now starting to produce 8-ft² amorphous silicon tandem modules in a new plant in Virginia and has initiated new programs to develop the grid-connected markets in the USA and overseas. However, the current USA lead in photovoltaics is in jeopardy as government programs in both Japan and Germany are aggressively supporting the development of building integrated photovoltaic systems in those countries. In order to maintain its leadership in photovoltaics, the USA needs to implement a new national initiative to support the development of building integrated photovoltaics. © 1997 John Wiley & Sons, Ltd.     

PV home opens in Boston

The first new Energy Star Homes development to incorporate a PV system has opened in the Boston, Massachusetts suburb of Wrentham. A dozen Evergreen Solar PV panels on the each home’s roof are expected to generate 1250 kWh per year, based on New England’s climate.Visit www.re-focus.net for the latest renewable energy industry news     

光伏锑化铟红外探测器的电容效应

在调制信号下工作的光伏锑化铟红外探测器的探测率和响应率受探测器的交流特性的影响，减小探测器的电容有利于提高其电压响应率和探测率。     

Electrical PV Array Reconfiguration Strategy for Energy Extraction Improvement in Grid-Connected PV Systems

This paper applies a dynamical electrical array reconfiguration (EAR) strategy on the photovoltaic (PV) generator of a grid-connected PV system based on a plant-oriented configuration, in order to improve its energy production when the operating conditions of the solar panels are different. The EAR strategy is carried out by inserting a controllable switching matrix between the PV generator and the central inverter, which allows the electrical reconnection of the available PV modules. As a result, the PV system exhibits a self-capacity for real-time adaptation to the PV generator external operating conditions and improves the energy extraction of the system. Experimental results are provided to validate the proposed approach.     

The Distributed Flight Array

The Distributed Flight Array is a multi-rotor vehicle that is being developed at ETH Zurich. This vehicle consists of autonomous single-rotor modules that are able to drive, dock with its peers, and fly in a coordinated fashion. These modules are organized as distributed computational units with minimal sensory input. Experimental demonstrations in docking, driving, and flying have proven its feasibility as a research platform for investigating techniques in distributed estimation and control.     

On the necessity of joint adoption of both Distributed Maximum Power Point Tracking and Central Maximum Power Point Tracking in PV systems

In this paper, the main causes that are able to limit the efficiency of Distributed Maximum Power Point Tracking (DMPPT) are analyzed in detail. It will be shown that, to get full profit from DMPPT, it is necessary that the bulk inverter voltage belongs to an optimal range whose position and amplitude are functions of the following factors: the number of PV modules and dedicated DC/DC converters in a string, the atmospheric operating conditions characterizing each PV module (irradiance and temperature values), the voltage and current ratings of the physical devices the DC/DC converters are made of, and the adopted DC/DC converter topology. Moreover, it will be given proof of the necessity to couple the DMPPT function with a suitable centralized MPPT function carried out by the inverter through the proper control of its own DC input voltage. Copyright © 2012 John Wiley & Sons, Ltd.     

The role of silicon solar cell fabrication in intermediate-level PV training

Appropriate regionally-based training is of major importance for improving the market penetration of basic PV systems in developing countries. This communication describes an initiative at a Brazilian university where science and engineering undergraduates are encouraged to fabricate, test, and package crystalline silicon solar cells.     

AOI在PCB检测过程中的有效应用方案

随着电子产品对信号传输速度的要求越来越快,相对的对PCB图形的完整性和一致性要求也越来越高,有效地控制PCB图形的完整性与一致性,提升产品质量,作为PCB的重要检测设备AOI(Automatic Optical Inspection)自动光学检测设备是必不可少的。由于AOI设备价格成本较高,如果不能根据不同PCB加工工艺的实际情况,根据不同AOI的优缺点,有效地配置AOI,利用AOI,使AOI的能效发挥到最大,无疑是一个巨大的资源浪费。这就需要我们根据不同产品状况,分析产品结构及加工工艺的特点,分析不同工艺缺陷的规律性,合理配置AOI,加强产品控制力度,提升AOI检测效果,以使有效的资源产生更大的效益。本文通过分析不同类型AOI的优缺点,以及不同PCB加工工艺产生缺陷的差异,合理配置、应用AOI,以发挥AOI在PCB检测过程中的最大能效,降低成本,提高产品品质。     

光伏阵列低能耗趋光性研究

针对太阳能光伏阵列转换效率低这一问题,提出了一种简单可行并且能耗低的光伏阵列趋光性控制方法,来提高光伏系统的转换效率。这里采用双轴追踪模式,利用天文学的计算公式,结合当地地理经纬度信息,测算出不同时刻的太阳的方位角和高度倾角,以此作为基准,进行粗略定位,并根据实时光照强度数据,对光伏阵列的位置进行精确调节。系统的全部控制均由DSP及外围电路来实现。通过实验所得到的数据验证了此方法的实用价值。     

LSPMIS系统分布式数据库设计

本文论述基于网络的MIS系统中分布式数据的特点、功能和设计与实施技术，并结合LSPMIS系统中分布式数据库的具体设计与实施给出了设计过程、步骤、方法和结果。     

CORBA分布式系统的面向对象分析

ＣＯＲＢＡ是一种新兴的面向对象分布式计算技术,为建立大型复杂的分布式应用提供了一条新的思路。产生简洁合理的接口文件是实现ＣＯＲＢＡ应用中的一个关键问题。对传统的面向对象分析方法加以改进,将其应用于ＣＯＲＢＡ分布式系统的分析中,以充分利用ＣＯＲＢＡ系统的新特点,简化整个系统的分析过程,便于软件的设计和实现。     

基于XC164CM的光伏并网发电系统

并网发电系统是太阳能利用的主流趋势,而高性能数字信号处理器的发展也使得一些先进复杂的控制策略应用于光伏并网系统成为可能。文中对系统的控制方案进行了分析,并采用英飞凌公司生产的XC164CM作为系统的控制芯片,通过软件编程完成了系统的并网控制,并解决了最大功率点跟踪、锁相环等关键问题。实验表明文中设计的光伏并网发电系统能够较好地实现逆变并网功能。     

Photovoltaics in architecture in The Netherlands: an architect's view

The Netherlands has a programme for the integration of photovoltaic (PV) modules in the built environment. The aim of this programme is to realize 250 MWp in PV systems by the year 2010. Within this programme the integration of PV modules in architecture has an important role, presenting opportunities for architects. New Technology and materials are an invitation for new design. BEAR Architecten is involved in several low-energy, bio-climatic building projects, amongst them are a few PV projects: De Kleine Aarde, an Environmental Education Centre with transparent PV panels in the glass roof; roof retrofit with PV modules in five houses in Leiden; facade integration with PV shading in 22 houses in Dordrecht; roof integration in row houses in Enschede; roof integration in a utility building in Geldermalsen. Information about these projects is given, but also the possibilities and the problems are discussed here. A general conclusion is that custom-made modules are often necessary to make well-designed buildings.     

光伏锑化铟红外探测器的老化现象与处理

光伏锑化铟红外探测器在长期使用过程中会逐渐老化,出现一些如等效阻抗降低、噪声增大等现象。本文叙述了闪光处理对于降低这类老化的探测器的噪声特别有效,加上一些清洁措施,已使一个工作了6年多的探测器基本上恢复了性能。