燃料电池中机电一体化系统英文及翻译毕业论文.doc

Mechatronics in fuel cell systemsAnna G. Stefanopoulou Kyung-Won SuhMechanical Engineering Department, University of Michigan, 1231 Beal Avenue, Ann Arbor, MI 48109, USA燃料电池中机电一体化系统Anna G. Stefanopoulou Kyung-Won Suh美国MI48109安阿伯市比尔大街1231号密歇根大学机械工程系AbstractPower generation from fuel cells (FCs) requires the integration of chemical, fluid, mechanical, thermal, electrical, and electronic subsystems. This integration presents many challenges and opportunities in the mechatronics field. This paper highlights important design issues and poses problems that require mechatronics solutions. The paper begins by describing the process of designing a toy school bus powered by hydrogen for an undergraduate student project. The project was an effective and rewarding educational activity that revealed complex systems issues associated with FC technology.摘要燃料电池(FCs)的发电,需要整合化学、流体、机械、热、电和电子子系统。这种综合系统在机电一体化领域提出了许多挑战和机遇。本文重点强调设计问题,提出了该问题需要用机电一体化方案来解决。本文首先描述了本科学生项目为一个玩具校车设计采用氢为燃料的燃料电池的流程。该项目是一个有效和有益的教育活动,揭示复杂系统与FC技术相关的问题。KeywordsFuel cell;Power;Multivariable;Feedback control;Mechatronics关键词燃料电池;权力;多变量;反馈控制;机电一体化1. IntroductionThe fuel cell (FC) principle dates back to the early 1800s (Schnbein, 1839). Only recently, however, have FCs become a promising alternative to internal combustion engines (ICEs) and thus are considered for transportation (automotive, marine and aerospace) applications and distributed power generation. FCs are very efficient because they rely on electrochemistry rather than combustion. Specifically, water, electrical energy, and heat are created through the combination of hydrogen and oxygen. The major breakthroughs that have recently brought FCs to the fore-front include the development of low resistance membranes, highly diffusive electrodes, and reduced use of noble metal catalysts. Moreover, efficient power electronics and electric motors can now effectively utilize and distribute the electricity generated from the FC. All these advances have led to many experimental demonstrations. It is the application of mechatronics concepts, however, that will allow the FCs to move from laboratories to streets, powering automobiles, or to our basements, heating and cooling our houses.1.介绍燃料电池(FC)原理可以追溯到1800年代初(Schnbein,1839)。直到最近,然而,已经成为一个有望替代内燃机,因此被认为在运输(汽车、海洋和航空航天)应用和分布式发电方面很有价值,因为他们依靠电化学而不是燃烧。具体来说,通过氢和氧的结合产生水、电能和热。主要的突破在于最近FCs带来的最前沿包括研发低电阻膜、高扩散电极,并减少使用贵金属催化剂。此外,现在FC可以使动力电子设备和电动机有效利用和分配电能。这一切进展都使得许多实验可以进行。它是应用机电一体化的概念,然而,这将允许FCs从实验室到街道电动汽车,或者我们的地下室,为我们的房子供热制冷。Our ability to precisely control the reactant flow and pressure, stack temperature, and membrane humidity is critical for the efficiency and robustness of the FC stack system in real world conditions. These critical FC parameters need to be controlled for a wide range of operating conditions by a series of actuators such as relays, valves, pumps, compressor motors, expander vanes, fan motors, humidifiers and condensers. Precise control with low parasitic losses is the challenging goal of the FC auxiliary system. Moreover, estimation and real time diagnostics should be developed to augment the limited sensing capability in FCs. Finally, a snapshot into the FC industrial arena, namely, partnerships and joint ventures among automotive companies, component suppliers, and development laboratories indicates that there is a strong need for modular control architectures. FC vehicles, for example, have an FC stack controller, vehicle (e.g. chassis, cooling) controllers, and an electric traction motor (TM) controller. Guidelines for the hierarchy and the coordination of all these controllers will allow their independent development and ensure a minimum level of integration.在实际情况下我们能够利用FC堆栈系统精确地控制流动反应物的和压力,温度,湿度和反应稳定性是至关重要的。关键的FC参数需要控制大量的操作条件和一系列执行机构如继电器、阀门、泵、压缩机、膨胀机叶片马达,风扇电机,增湿器和冷凝器。精确的控制这些对于FC辅助系统是具有挑战性。此外,在FCs估计和实时诊断必须增加有限的传感能力。最后,一个简单的FC应用到工业领域,需要合伙企业和合资企业在汽车公司、零部件供应商和实验室发表说明,模块化控制架构。例如,FC车辆,有一个FC堆栈控制器、车辆(如底盘、冷却)控制器,电动牵引电动机(TM)控制器。指导层次结构和协调所有这些控制器将允许他们独立发展和确保最低级别的集成。The interactions among many thermal, chemical, electrical, and psychrometric subsystems require complicated models that are neither easy to compile nor simple to use in model-based controllers. This paper presents various FC subsystems, their models, and their integration from a controls and mechatronics perspective. The paper starts with a containable FC design project that was undertaken within one semester by a team of undergraduate students. The FC design is described in detail to familiarize the reader with the FC dimensions and parameter values. Despite the simplicity of the design project, it presents a concrete case study where design and control iterations are needed. The sections that follow the design project provide a comprehensive discussion of the FC system.需要许多热、化学、电气、湿度子系统间的相互作用的复杂模型,基于模型的控制器既不容易编译也不容易使用。本文从一个学期的学生团队在一个俱乐部进行可控制的设计项目开始,从控制和机电一体化视角介绍了各种FC子系统,其模型,及其集成。FC设计是详细描述以熟悉读者与FC尺寸和参数值。尽管是简单的设计项目,但它提出了设计和迭代控制的是一个具体的案例研究必要的。接下来的设计项目小节提供的全面讨论FC系统。2. The FC toy school busA team1of four senior undergraduate students in the Mechanical Engineering Department at the University of Michigan designed and built a toy hydrogen powered bus that runs at constant speed around a hilly route emitting only water. The road grades were modeled after a popular university bus route, which is currently served every 15min by buses powered with diesel fuel or natural gas. The semester-long project allowed us to understand the mechatronics and design issues surrounding hydrogen-powered vehicles. The project and its pedagogical aspects stressed cross-disciplinary involvement and combined control and design concepts for the analysis and synthesis of technologies important to our environment.Fig. 1shows three of the team members on the day the project was exhibited to the public and the jurors.2.FC玩具校车在密歇根大学一个由四个高级本科学生组成机械工程小组设计并制作了一个玩具氢动力汽车,在一个仿照普通的陡坡路上以恒定速度运行大学洒水车路线的,每15分钟由柴油或天然气提供公共汽车动力。这个学期的项目让我们了解机电一体化和氢环境动力汽车的设计问题。这个项目和它的教学方面强调综合分析跨学科联系联合控制和设计理念的的技术我们的环境的重要。图1是三个团队成员的向公众和陪审员展出当天项目。Fig.1.Tim, Sarah, and Dave (from left) putting the final touches to their FC toy bus.图1 蒂姆,莎拉,戴夫(左起)启动他们的FC玩具公共汽车。2.1. The FC toy bus propulsionThe design goals included a small size (less than) and light weight toy bus that can run for 3h on 15% road grades at 10cm/s velocity. The total project budget was less than $1500. The selection and sizing of the toy FC bus components was challenging because there were few benchmark examples that could provide initial data. Moreover, linear scaling did not apply to the power, volume, and weight of FC vehicles so published data from experimental full-size FC vehicles could not be used. A further challenge was that commercially available FC components in the desired range of size and weight considerably narrowed the design parameter space.A FC stack of three (3) proton exchange membrane (PEM) cells with maximum power 3W was found in a FC store (Fuel Cell Store, n.d.). It was fortunate that a FC at this lower power range was available, but it was quickly realized that the FC toy bus would have a very low specific power when compared to full size experimental FC vehicles which have reached 200W/kg (Friedlmeier, Friedrich, & Panik, 2001). The 3W FC stack weighed 1kg with dimensions. Therefore, the FC stack occupied a fifth of the total bus volume. Moreover, a quick calculation showed that the FC stack weight alone would be 25% of the total weight that the fuel cell could drive uphill at a 15% grade at 10cm/s speed assuming 20% powertrain efficiency (9.810.15 0.1/0.2).2.1. FC玩具公共汽车牵引力设计目标包括在15%道路等级10 cm / s的速度体积小和重量轻的玩具公共汽车可以运行3 h 。总项目预算还不到1500美元。玩具公共汽车组件的选择和涂料是具有挑战性的,因为俱乐部只有很少可以提供最初的基准数据的例子,。此外,实验FC车辆的电力、体积和重量数据并不适用于线性扩展所以无法使用到现实的FC车辆。另外一项挑战是,市面上的FC组件参数范围的大小和重量限制了设计空间。在北达科他州一个燃料电池店俱乐部发现了三个质子交换膜(PEM)单元堆叠的FC最大功率可达3 W。这是幸运的,一个FC俱乐部在这个低功率范围是可用的,FC玩具公共汽车将会有一个非常低的功率系数,实验FC车辆达到200 W /公斤。3 W FC重1公斤。因此,FC占据总线体积的五分之一。此外,计算表明,假设20%动力系统效率( 9.81 0.15 0.1/0.2 )FC需要占25%的重量,燃料电池可以开车上山15%品位在10厘米/秒速度。More technical details were obtained from the FC manufacturer. The nominal FC stack voltageVstwas specified as 2.4V at 1A of current. The FC stack relied on convection for air (oxygen) feed and cooling without the need for a blower. A low pressure hydrogen feed with minimum supply of 2.2l/h of hydrogen was required. The specified supply corresponded to hydrogen excess ratiobased on the H2reacted to support 1A of current. Specifically, electrochemistry principles were used to calculate the rate of hydrogen consumption in the FC reaction based on the stack current, the number of cellsn=3, the hydrogen molar mass, the hydrogen densityatand 100kPa, and the Faraday numberF=96485从FC制造商可获得更多的技术细节。名义FC堆栈电压设定为2.4 V在1 A的电流。FC堆栈依靠空气对流提供氧气和冷却而不需要一个吹风机。另一个提供低压氢气供应最少的需要的氢流量2.2 l / h。供应过量空气和确定的与氢气反应来产生1 A的电流。具体来说,通过FC反应的堆栈电流用电化学原理来计算氢的速度消耗,单元的数量n = 3,氢气摩尔质量、在氢密度和压强100 kPa,法拉系数F = 96485equation(1)方程(1)TurnMathJaxonThe next step was the identification and sizing of the on-board hydrogen storage. As was the case with the FC selection, the commercially available hydrogen storage options were very limited for the desired power and volume range. A metal hydride storage bottle was found in a FC store. Metal hydride tanks were chosen as alternatives to the liquefied cryogenic or compressed hydrogen storage. Metal hydride absorbs hydrogen and releases heat as the tank is filled with hydrogen. Conversely, the hydrogen is released by reducing the pressure and generating heat (Jeong & Oh, 2002).下一步是识别和分级的车载储氢。的情况也是FC选择、商用氢存储选项非常有限,所需的功率和体积范围。俱乐部在一个商店发现金属氢化物存储瓶。金属氢化物被选为替代液化气低温或压缩储氢。充满了氢气槽金属氢化吸收氢和释放热量。相反,氢释放通过减少压力和生成热(Jeong & Oh, 2002)。The metal hydride bottle was specified as absorbing and releasing 20l of hydrogen in a volume of 0.74l and weighed 366g. The bottle could provide nine continuous hours of run time, based on a supply rate of 2.2l/h required by the 3W FC. The manufacturer suggested operating the FC stack without restricting the anode exit and thus maximizing the supply rate. This mode of operation is also known as “open-ended anode”. The actual running time that was finally achieved by the FC toy bus was 3.6 times lower than expected, indicating high hydrogen losses or lower stored H2volume.瓶金属氢化物重366 g设定为20 l的吸收和释放氢的体积的0.74 l。瓶子可以提供9个连续数小时的运行时,基于供应率的2.2 l / h所需要的3 W FC。制造商建议的操作FC堆栈没有限制出口,从而最大化阳极供应率。这种方式的操作也称为“开放式阳极”。通过FC玩具公共汽车实际的运行时间,是低于预期的3.6倍,表明提高氢损失或降低存储H2体积。The chassis was designed and laser cut out of0.25thick plexiglass. Several layers were stacked and fused with methylene chloride solvent to support the weight of the FC and electronics and prevent excessive bending. The FC stack was placed in the front of the vehicle to allow unobstructed air flow. To accommodate the rear-wheel drive and achieve a good weight balance the electric drive and the hydrogen tank was placed with all the electronics in the rear, as shown in Fig.2. Two supports were manufactured so that the bottle could slide in and out easily for refilling. Finally, the roof of the bus could be removed to allow for easy access to the components.底盘设计和激光切割出0.25英寸厚的有机玻璃。几层堆放和熔融与二氯甲烷溶剂支持FC的重量和电子产品和防止过度弯曲。FC堆栈被放置在前面的车辆允许气流通畅。为了容纳后轮驱动,实现良好的重量平衡电力驱动和氢槽放置所有的电子在后面,见图2。两个支持生产,这样瓶子可以很容易拆装。最后,公共汽车的顶可以去掉,以便轻松拆卸组件。Fig.2.The components arranged in their final position in the chassis.图2.底盘上安装组件的最终位置。The track was designed as a figure-eight manufactured of plywood and plaster. The middle of the track was grooved to guide the front steering mechanism of the bus, which was a simple hinge attached to the front pivoting axle of the toy bus.轨道设计为一个数字八型石膏胶合板。中间的轨道槽导前转向机构的公共汽车,这是一个简单的铰链固定在前转动轴的玩具汽车。2.2. The electric powertrain2.2. 电动动力系统Having specified the FC power (voltage and current) and ensuring adequate hydrogen supply the powertrain was designed as follows. The 2.4V and 1A was sent to the DC/DC converter where it is stepped up to the output voltage required for the TM. A schematic of the overall powertrain is shown inFig. 3.有指定的FC功率(电压和电流)和确保足够的氢供应汽车动力系统设计如下。2.4 V和1一个被送到了直流/直流转换器,它加大了输出电压所需的TM。整体传动系统的示意图显示在图3。Fig.3.The information (dashed line) or energy (solid line) flow for the powertrain components along with specifications.图3.信息(虚线)或能量(实线)流的动力以及传动部件规格。In selecting a motor, several requirements had to be met. These included the power necessary to drive the toy bus, as well as low power consumption, integrated encoder feedback, and a small size. The power requirements were satisfied by the Micromo 1524SR DC motor with an integrated 16 line magnetic encoder. The motor achieves a range of 1.73W maximum power output with 0.45% efficiency (requires 3.84W of input power) or 0.76W output power with the maximum efficiency 0.76% (requires 1.0W of input power). The DC motor operates at an input voltage range of 56.5V with the optimum being equal to 6V.在选择电动机,几个需求必须得到满足。这些包括必须的力量驱动的玩具汽车,以及低功耗、集成编码器反馈,和一个小的尺寸。电力的需求都被满足的Micromo 1524 sr直流电机集成16线磁编码器。电机达到一系列1.73 W的最大输出功率与效率0.45%(要求3.84 W的输入功率)或0.76 W输出功率与最大效率0.76%(要求1.0 W的输入功率)。直流电机的操作在一个输入电压范围的5 - 6.5 V与最佳等于6 V。Anticipating some voltage drop from the FC, a DC/DC converter was chosen to step-up the quoted FC stack voltage 2.46.5V in the DC/DC output. The DC/DC converter was implemented using a LM2578A switching regulator manufactured by National Semiconductor. The output of the DC/DC converter was sent to a BASIC stamp controller and a transistor-switching module for current control to the DC motor. The BASIC stamp controller drewat 6.5V, and output 4000 instructions per second. The encoder, drawing, measured the angular velocity of the motor and provided the information to the BASIC stamp controller. The inputs to the transistor-switching module were the DC/DC converter power output and the output of the BASIC stamp controller. The heart of this switching module was a TO-92 type transistor made by Zetex that drew.预期电压降从FC、直流/直流转换器被选为升压的引用FC堆栈电压2.4 - -6.5 V的直流/直流输出。直流/直流转换器是实现使用一个LM2578A开关调节器采用美国国家半导体公司。输出的直流/直流转换器被送到了一个基本的邮票控制器和一个晶体管开关模块电流控制的直流电机。基本的邮票控制器德鲁在6.5 V,输出每秒4000条指令。编码器,图纸,测量角速度的电动机和提供信息的基本邮票控制器。输入到晶体管开关模块的直流/直流转换器输出功率和输出的基本邮票控制器。这个开关模块的核心是一个到- 92型晶体管由Zetex,画了。The motor drew the current from the transistor-switching module, and used it to mechanically rotate the shaft at a speed that depends on the current delivered. The maximum current that was delivered to the motor was汽车引起了电流的晶体管开关模块,并使用它来机械转动轴速度,取决于当前的交付。的最大电流, 送到了电动机The transistor-switching module then regulated its electrical output and consequently controlled the motor speed up to a maximum of 6V and 250mA for the bus to go uphill. A current of 0.250A corresponds to motor output of 1.113W with 71.6% efficiency and 7700rpm based on the manufacturer map. A 152:1 planetary gear results in an axle rotation speed of 53rpm. The axles rotational speed was then geared up with 3.8cm diameter wheels, giving the toy bus a speed of 10cm/s around the track.这个晶体管开关模块然后输出电,从而调节其控制电机速度最高达到6 V和250毫安公共汽车去上山。一个电流的0.250一个对应于电动机输出1.113 W效率为71.6%和7700 rpm基于制造商地图。一个152:1行星齿轮的结果在一个轴旋转速度53 rpm。轴的转速是然后作好准备与3.8厘米直径的车轮,让玩具公共汽车的速度10 cm / s周围的轨道。The BASIC stamp controller processed the measured rotational speed of the motor by counting the encoder pulses within 4ms. The controller then sent a high or low voltage signal to the transistor that in turn controlled the current to the motor. Aresistor was sized and used to match the highlow voltage from the BASIC stamp controller to the onoff voltage inputs to the transistor.Since the motor was, in effect, turning on and off very rapidly, some safeguards to protect both the motor and the electronics were necessary. Due to the motors inherent inertia, when no voltage was being applied, the motor continued to spin, forcing current through the line. This could have easily shorted out the transistor if not accounted for. To protect against this, a fly-back diode was placed in parallel with the motor as a safety valve. Also, to eliminate voltage spikes due to the transistor switching a small capacitor (100pF) was added in parallel.基本的标识控制器处理测量转速的电动机通过计算脉冲编码器在4控制器然后发送女士高或低电压信号到晶体管,从而控制电机的电流。一个电阻是大小和用于匹配高低压从基本的邮票的开关电压控制器的输入晶体管。直接作用马达,事实上,打开并关闭非常迅速,一些保障措施既可以保护电机和电子是必要的。由于电动机的固有的惯性,当没有电压被应用,电机继续旋转,迫使电流通过线路。这可能很容易短路的晶体管如果不占。来防止这一点,一个回程二极管放置在平行与电动机作为一个安全阀。同时,消除电压峰值由于晶体管开关小电容器(100 pF)添加于并行。In summary, the toy FC bus had the following sub-systems shown inFig. 3: metal hydride storage bottle, 3W fuel cell, DC/DC converter, BASIC stamp controller, transistor-switching module, 6V DC motor, digital encoder, planetary geartrain, wheels/chassis, steering, and track.总之,玩具FC总线有以下子系统显示在图3:金属氢化物存储瓶,3 W燃料电池,直流/直流转换器,基本标识控制器,晶体管开关模块、6 V直流电机、数字编码器,行星轮/底盘、转向,并跟踪。2.3. Hybrid FC+battery power2.3. 混合FC 电池供电After frantic preparation and multiple inspections of the individual components the students connected all the parts except the H2supply. The toy bus and its track were taken to a space with adequate ventilation in case of a potential H2leak. The fully charged metal hydride tank was connected to the FC anode inlet and FC toy bus started spinning its wheels.经过紧张的准备和多个检查单个组件连接的所有部分的学生除了H2供应。玩具汽车和它的轨道被带到一个空间有足够通风以防潜在H2泄漏。完全充电的金属氢化物坦克被连接到FC阳极入口和FC玩具公共汽车开始旋转的轮子。In its initial run, the toy bus ran through the flat part of the track but was unable to negotiate the 15% grade. Further investigation showed us that the FC voltage dropped to 1.8V at 1A current which prevented the FC toy bus from being pulled up the specified grade. In hindsight the low voltage (0.6V per cell) was more realistic given other published data, so it was not possible to complain to the manufacturer except to ask for a FC with larger active area that would allow higher current at 0.6V per cell, or the integration of one more cell into the stack. Requesting a new FC stack was not, however, an option because a new FC volume and weight would require substantial re-des