MEMS微型燃料电池及其基于压电风扇的换气方法

介绍了基于MEMS的微型燃料电池的国内外研究动态,对其技术关键进行了阐述.在此基础上,对微型燃料电池的换气方法进行了研究.提出一种低功耗、体积小的压电风扇,对其力学模型进行了分析,并进行了风速、振幅、功耗等方面的实验研究,初步证明其应用于微型燃料电池换气的可行性.     

MEMS微型燃料电池及其基于压电风扇的换气方法

介绍了基于MEMS的微型燃料电池的国内外研究动态，对其技术关键进行了阐述。在此基础上，对微型燃料电池的换气方法进行了研究。提出一种低功耗、体积小的压电风扇，对其力学模型进行了分析，并进行了风速、振幅、功耗等方面的实验研究，初步证明其应用于微型燃料电池换气的可行性。     

压电驱动膜片式微型气泵

提出一种结构新颖的压电驱动膜片式微型气泵，对其输出流量、膜片的振幅等参数进行了理论分析，在此基础上设计、制作了微型气泵样机，并进行了测试实验。这种气泵在结构上充分利用了双压电梁端部位移大的优点，并利用两根双压电梁将膜片悬起，增加了容积变化率和输出流量，并具有结构简单，功耗低，厚度小，无电磁噪音，可靠性高等优点，在微型电子器件的冷却、微型燃料电池换气等方面显示出良好的应用前景。根据实验，微型气泵的一阶固有频率约为120Hz，在谐振状态下，当驱动电压为50V时，其输出流量为192mL／min，功耗小于23mW。     

一种高效的微型能源系统——微型燃料电池

本文介绍了微型燃料电池系统的优点．分类．应用前景以及国内外研究现状。还分析了应用微型燃料电池市场化所必须解决的一些问题。最后并对微型燃料电池的前景作了初步展望。     

基于硅的微型燃料电池的研究

介绍了基于硅的微型燃料电池的国内外研究动态，总结了微型燃料电池的研究成果，并对其制作方法中的关键技术进行了阐述。在此基础上，根据微通道的特性，分析了电极板上各种不同截面形状的气道对微型燃料电池性能的影响。当由气道决定的水力直径Dh由大变小时，在同样的实验条件下，电池性能开始逐渐变好，达到一个最佳值后，性能又逐渐下降。     

微型燃料电池将会取代充电电池？

近年来，很多企业和研究机构在进行燃料电池技术方面的研发，最近有了新的进展。前不久，几家公司宣布他们已经具备了制造微型燃料电池的技术。其中日本的东芝和NEC特地展示了几台内置有他们自己开发的燃料电池的笔记本电脑原型机。NEC公司计划在2004年年底把这种内置有燃料电池的笔记本电脑投放市场，并打算在2005年年底前制造出能持续工作40小时的燃料电池。日本的东芝和索尼公司也同时加入到了研制微型燃料电池的竞争行列，而且这两家公司把目标定位在生产更小的燃料电池上，从而去取代目前正用于掌上电脑、     

新固体氧化物燃料电池研制成功

日本产业技术综合研究所日前宣布,该所研究人员和美国同行研制出一种微型固体氧化物燃料电池,这种燃料电池添加了特殊的催化剂层,可大大降低电池的工作温度。     

微型燃料电池将取代手机电池

根据著名的芯片制造商意法半导体(ST)的最新研究成果,将来,人们无需再给手机、笔记本等便携终端的电池定期充电。ST已经在微型燃料电池开发上取得了新的进展,这种能够装进手机内的微型燃料电池,利用价格低廉、货源充足的有机燃料,为手机提供工作所需的全部能量。虽然在燃料电池技术的新兴应用领域,主要是以汽车应用为目标,但是,ST的研究人员一直在进行采用小型燃料电池取代手机的充电电池的研究,这种小型燃料电池可以随时补充燃料,就像可以充气的打火机。通过开发新技术,ST在克服这个问题上取得了重大进步,新的燃料电池可以设计成3D结构…     

基于MEMS技术的自呼吸式微型直接甲醇燃料电池

报道了一种利用MEMS技术制作的微型直接甲醇燃料电池.其特点在于,利用KOH体硅腐蚀和双面光刻工艺制作了一种独特的三维自吸氧阴极结构.分析了MEMS制作工艺的改进.实验结果表明,该电池室温下产生了2.52mW/cm2的最大功率.此性能好于国外报道的同类基于MEMS技术制作的被动式微型直接甲醇燃料电池,并同本课题组之前报道的需使用外部泵的主动式微型直接甲醇燃料电池性能相当,证明了文中提出的新结构的可行性.     

An Air-Breathing Micro Direct Methanol Fuel Cell with 3D KOH-Etched Cathode Structure

报道了一种利用MEMS技术制作的微型直接甲醇燃料电池.其特点在于,利用KOH体硅腐蚀和双面光刻工艺制作了一种独特的三维自吸氧阴极结构.分析了MEMS制作工艺的改进.实验结果表明,该电池室温下产生了2.52mW/cm2的最大功率.此性能好于国外报道的同类基于MEMS技术制作的被动式微型直接甲醇燃料电池,并同本课题组之前报道的需使用外部泵的主动式微型直接甲醇燃料电池性能相当,证明了文中提出的新结构的可行性.     

Minimum Fuel Consumption Strategy for PEM Fuel Cells

This paper proposes a proton exchange membrane fuel cell control strategy to produce the power requested by an electrical load, minimizing the fuel consumption and also providing a regulated dc bus voltage to the load. The power system consists of a hybrid fuel cell/capacitor topology, and the control objective is to follow the minimum fuel consumption points for a given load power profile. This is done by controlling the air pump voltage and regulating the fuel cell current through a dc/dc switching converter. Moreover, the design and control parameters of the output dc bus are discussed, and the calculations are adjusted to a Ballard 1.2-kW Nexa power module. Finally, the control results, fuel consumption, and fuel cell protection against oxygen starvation phenomenon are analyzed and experimentally validated, contrasting its performance with the Nexa power module internal control system.      

建设节能型电信运营网络

在供电方式改革基础上选择可靠节能高效网元设备,可减少耗电和电热转换,从而降低供电设备配置和空调耗电.利用监控等手段达到精细化管理,控制和有效管理资源消耗.最终使运营商达到降低CAPEX和OPEX目的.     

Design and evaluation of a micro-fuel-cell-based power system for a mobile robot

A mobile robot being used for an undergraduate course in mechatronics engineering was converted from a conventional lead acid battery to a hydrogen fuelled polymer electrolyte membrane (PEM) micro fuel cell as the power source. The application of the robot is first outlined. Next, the design of the fuel-cell-based power supply system as assembled from the commercial components is described. Finally, the performance of the fuel cell is documented. The performance was found to match that of the conventional battery. An operational problem associated with the purging of water had to be solved. Although the cost of the fuel cell was 50 times that of the battery, the exercise did serve to demonstrate the potential of the technology.     

An Integrated Power Supply System for Low Power 3.3 V Electronics Using On-Chip Polymer Electrolyte Membrane (PEM) Fuel Cells

A stabilized power supply realized by chip-integrated micro fuel cells within an extended CMOS process is presented in this paper. The fuel cell system delivers a maximum power output of 450 ? W/cm². The electronic control circuitry consists of an LDO, an on-chip oscillator and a programmable timing network. The core system consumes an average power of 620 nW. The system reaches a current efficiency of up to 92% and provides a constant output voltage of 3.3 V.     

光杠杆式nm级微位移激光测量系统的研究

提出了一种全新的nm级微位移测量方法，改进了传统光杠杆测微位移的原理，研究开发了一种激光微位移测量系统。该方法可以将微位移量放大10^2量级以上，测量系统的理论分辨率为4nm、实测分辨率小于10nm，实验验证了该系统的可行性和可靠性。该系统适用范围广、灵敏度高、重复性好和结构简单，便于构成微电机系统（MEMS），实现系统微型化及自动化。     

基于DSP和FPGA的通用图像处理平台设计

设计一种基于DSP和FPGA架构的通用图像处理平台,运用FPGA实现微处理器接口设计,并对图像数据进行简单预处理,利用DSP进行复杂图像处理算法和逻辑控制,实现图像数据的高速传输与实时处理。系统可应用于贴片机芯片检测中,并进行性能评估实验。实验表明该系统满足实时性和功耗的设计需求,易于维护和升级,具备较强的通用性。     

非热式微流量传感器

基于微机械加工技术的微流量传感器是微传感器中重要的一种,目前,对微流体测量的研究主要集中在对流体流量和流速的测量上,按照测量方式的不同,微流量传感器可分为加热式和非加热式两种。本文概述了可以用来实现非热式微流量传感器的物理原理,并以此分类,综述了已有的非热式微流量传感器,对它们的优缺点进行了分析。通过对这些传感器进行的比较可以发现,虽然它们采取的原理和实现方法以及性能各不相同,但是它们有同样的优点就是功耗小。目前,阻碍非热式微流量传感器应用的最大障碍就是难以实现二维或三维方向的测量以及难以和标准CMOS工艺兼容。     

Fuel cell systems: efficient, flexible energy conversion for the21st century

At the beginning of the 21st century, fuel cells appear poised to meet the power needs of a variety of applications. Fuel cells are electrochemical devices that convert chemical energy to electricity and thermal energy. Fuel cell systems are available to meet the needs of applications ranging from portable electronics to utility power plants. In addition to the fuel cell stack itself, a fuel cell system includes a fuel processor and subsystems to manage air, water thermal energy, and power. The overall system is efficient at full and part-load, scaleable to a wide range of sizes, environmentally friendly, and potentially competitive with conventional technology in first cost. Promising applications for fuel cells include portable power, transportation, building cogeneration, and distributed power for utilities. For portable power a fuel cell coupled with a fuel container can offer a higher energy storage density and more convenience than conventional battery systems. In transportation applications, fuel cells offer higher efficiency and better part-load performance than conventional engines. In stationary power applications, low emissions permit fuel cells to be located in high power density areas where they can supplement the existing utility grid. Furthermore, fuel cell systems can be directly connected to a building to provide both power and heat with cogeneration efficiencies as high as 80%     

A Compact Digitally Controlled Fuel Cell/Battery Hybrid Power Source

A compact digitally controlled fuel cell/battery hybrid power source is presented in this paper. The hybrid power source composed of fuel cells and batteries provides a much higher peak power than each component alone while preserving high energy density, which is important and desirable for many modern electronic devices, through an appropriately controlled dc/dc power converter that handles the power flow shared by the fuel cell and the battery. Rather than being controlled to serve only as a voltage or current regulator, the power converter is regulated to balance the power flow to satisfy the load requirements while ensuring the various limitations of electrochemical components such as battery overcharge, fuel cell current limit (FCCL), etc. Digital technology is applied in the control of power electronics due to many advantages over analog technology such as programmability, less susceptibility to environmental variations, and low parts count. The user can set the FCCL, battery current limit, and battery voltage limit in the digital controller. A control algorithm that is suitable for regulating the multiple variables in the hybrid system is described by using a state-machine-based model; the issues about embedded control implementation are addressed; and the large-signal behavior of the hybrid system is analyzed on a voltage–current plane. The hybrid power source is then tested through simulation and validated on real hardware. This paper also discusses some important issues of the hybrid power source, such as operation under complex load profiles, power enhancement, and optimization of the hybrid system. The design presented here can not only be scaled to larger or smaller power capacities for a variety of applications but also be used for many other hybrid power sources.