PEMFC性能研究与仿真

质子交换膜燃料电池(proton exchange membrane fuel cell,PEMFC)具有能量转换效率高、相对于传统发动机振动低和噪声低及使用可靠等优点,逐渐成为研究的重点。燃料电池的系统建模需要掌握电学、电化学、热力学、流体力学等知识,提高了系统研究的门槛和复杂度。为了研究质子交换膜燃料电池系统特性,借助AMESIM建立一种燃料电池模型,在此基础上,分析燃料电池的电学特性。发现质子交换膜的厚度、气体扩散层和空气流速对电池性能有影响。     

RuO_2·nH_2O对质子交换膜燃料电池动态响应的影响

为了改善质子交换膜燃料电池在作为移动动力源时的动态响应,提出一种在质子交换膜燃料电池中引入RuO2·nH2O的方法,使质子交换膜燃料电池具备了超级电容器功能.首先以溶胶-凝胶法合成了RuO2·nH2O水溶胶,以提拉法将Nafion膜表面附上一层RuO2·nH2O;将此膜制成膜电极,通过对电极的循环伏安测试和对电池的稳态性能测试的结果证明了RuO2·nH2O的加入没有影响Pt的活性,对电池的稳态性能没有负面影响;通过对电极作多电位电势阶跃计时电流测试和脉冲电流下的电压响应测试,结果显示了RuO2·nH2O作为电容材料加入到质子交换膜燃料电池的膜电极中,在电池瞬间加载时可以缓冲电池电压大幅度衰减的现象,起到了改善电池动态响应的作用.     

燃料电池发动机水热管理仿真分析综述

质子交换膜燃料电池作为燃料电池中重要的一种类型,可应用于汽车及小规模的发电站与便携式移动能源,是当前新能源领域的研究热点。主要针对质子交换膜燃料电池不同维度的水热管理仿真模型的研究现状进行了论述。     

直接氢气质子交换膜燃料电池发动机管理系统研究现状与进展

直接氢气质子交换膜燃料电池发动机是一个复杂的综合系统,各个子系统之间存在强烈的耦合。从水管理机理模型、电堆经验模型、电堆和空气系统优化和包括系统级水热管理系统的发动机综合系统优化与控制等层次上论述了发动机管理系统的重要性、研究现状和进展,并提出了将电池水热管理模型、系统优化和智能控制相结合的开发思路。     

燃料电池空气供应系统条件敏感性研究

质子交换膜燃料电池的性能受运行条件参数影响较大,其中燃料电池发动机空气系统包含零部件多,电堆性能受空气路运行条件的影响较大,空气系统的标定工作任务繁重;针对质子交换膜燃料电池性能特性受空气路多参数影响大、标定任务繁重的问题,进行燃料电池空气系统的条件敏感性测试,研究燃料电池性能与空气温度、湿度、压力、流量的变化关系,分析空气路相关参数对燃料电池性能的影响机理。     

车用质子交换膜燃料电池仿真技术路线

质子交换膜燃料电池作为燃料电池中重要的一种类型,可应用于汽车及小规模的发电站与便携式移动能源,是当前新能源领域的研究热点。主要针对车用质子交换膜燃料电池的三种仿真参数模型就当前国内外研究进展进行论述。     

质子交换膜燃料电池-四温位吸收式制冷机混合系统性能分析

建立质子交换膜燃料电池-四温位吸收式制冷机混合系统模型,该模型考虑包括燃料电池热力学和电化学不可逆性、吸收式制冷循环不可逆性在内的主要损失,导出系统总的输出功率和效率表达式,以及吸收式制冷循环的制冷量及制冷系数关系式。通过数值计算探讨混合电池系统的整体性能,分析不同运行工况参数对混合系统性能的影响规律,得出电流密度、输出功率、效率等重要参数的优化工作区间。系统对质子膜燃料电池的余热进行合理利用,使质子膜燃料电池混合系统总的输出功率以及效率都有了较大的提高。     

质子交换膜燃料电池的一维气体扩散模型研究

目前对质子交换膜燃料电池(PEMFC)的系统性能进行分析时,多采用集总参数模型。它无法体现电池内部结构对系统性能的影响。本文建立了PEMFC沿膜厚方向的一维结构模型,通过分析在电池阴、阳极的气体扩散规律,研究气源压力、温度对电池输出电压的影响。通过与不同条件下的实验结果以及集总参数模型进行比较,本文的仿真结果更加符合实验结果,适用范围更广,可为车用燃料电池的优化和控制提供可靠依据。     

锁紧螺栓数目及位置对PEMFC双极板变形影响

质子交换膜燃料电池的组装设计及方法对电池性能的优劣,有着非常重要的影响。燃料电池在组装时,由于受到螺栓锁紧时外力的作用,各组件之间容易产生变形。针对锁紧螺栓个数及位置,采用有限元ANSYS/WORKBENCH分析软件建立单质子交换膜燃料电池模型,对螺栓锁紧所造成的双极板内部位移变化情况进行数值模拟,获得双极板沿给定路径的位移变形分布和翘曲度情况,对比分析了锁紧螺栓数目及位置对双极板翘曲变形的影响,得出了最佳锁紧螺栓个数及位置,并提出了一种能提高质子交换膜燃料电池性能的封装方案。     

基于自抗扰原理的燃料电池阳极压力控制研究

车用燃料电池在实际工况中容易产生供气波动、内部温度分布不均等问题导致阳极内部压力不稳定,严重影响了其市场化推广。通过控制方式的设计可以优化上述问题,针对质子交换膜燃料电池(PEMFC)阳极压力的仿真、跟随和控制等问题,论述了基于自抗扰原理的质子交换膜燃料电池死端模式阳极的建模过程,并在Simulink环境下通过仿真证明了基于自抗扰原理控制方式的有效性。仿真结果验证了该仿真系统的实用性和有效性,该仿真系统能够使质子交换膜燃料电池阳极压力有效跟随阴极压力,能够对温度、压力变化等扰动具有抵抗效果,跟随速度快,准确度高,超调极少。     

Influence of thermal management and integration with turbomachinery on the performance of polymer electrolyte membrane fuel cell systems

Polymer electrolyte membrane fuel cells (PEMFCs) have many good characteristics for small power sources such as low operating temperature and high power density. In this study, the effects of thermal management on the performance of PEMFC systems using natural gas fuel, and the effects of integrating PEMFC systems with turbomachines, were investigated. Firstly, performance of various system configurations differing in the thermal management of reforming and stack cooling processes was comparatively analyzed. Then, various integrated system combinations with turbomachines (compressors and turbines) were analyzed. We performed a parametric analysis of the influence of turbine inlet temperature and compressor pressure ratio on system performance, and a 10% difference in efficiency among four simple PEMFC systems was predicted. Pressurization of the PEMFC with adequate thermal management may improve system efficiency, while efficiency enhancement from corresponding simple PEMFC systems was hard to achieve in the ambient pressure integrated systems.     

不同参数对质子交换膜燃料电池输出特性的影响

针对质子交换膜燃料电池(Proton Exchange Membrane Fuel Cell,PEMFC)的性能主要受到物理参数影响的问题,通过FLUENT软件建立燃料电池动力学模型,以对物理参数进行研究,得到了直行多流道单体质子交换膜燃料电池的极化曲线并对输出性能进行对比.结果表明:升高工作温度、升高运行压力以及降低...     

Dynamic behavior modeling of a polymer electrolyte membrane fuel cell power generation system

This paper presents models for simulating the operation of a polymer electrolyte membrane fuel cell (PEMFC) system and the results of the dynamic simulations. The entire system included a PEMFC stack and balance-of-plant components such as an air supply blower, a membrane humidifier, a fuel supply unit, and a heat management unit. Mathematical modeling for the computation of power generation and heat transfer of the PEMFC stack, the heat and mass transfer of the humidifier, and the energy transfer of the cooling system was set up. Theoretical and experiential data such as the voltage-current density relationship of the cell stack and the performance maps of blowers and pumps, together with semi-theoretical heat and mass transfer equations, were used to represent the characteristics of all the components. The effect of the thermal inertia of solid parts was considered in the fuel cell stack, the membrane humidifier, and the radiator. System dynamic behaviors under various operating conditions due to changes in stack current and ambient temperature were predicted. The sudden abnormal operations of the cooling water circulation pump and the radiator fan were also simulated as an example of component malfunctions.     

The effect of channel flow pattern on internal properties distribution of a proton exchange membrane fuel cell for cathode starvation conditions

The effect of channel flow pattern on the internal properties distribution of a proton exchange membrane fuel cell (PEMFC) for cathode starvation conditions in a unit cell was investigated through numerical studies and experiments. The polarization curves of a lab-scale mixed serpentine PEMFC were measured with increasing current loads for different cell temperatures (40, 50, and 60°C) at a relative humidity of 100%. To study the local temperature on the membrane, the water content in the MEA, and the gas velocity in terms of the channel type of the PEMFC with operating characteristics, numerical studies using the es-pemfc module of STAR-CD, which have been matched to the experimental data, were conducted in detail. The water content and velocity at the cathode channel bend of the mixed serpentine channel were relatively higher than those at the single and double channels. Conversely, the local temperature and mean temperature on the membrane of a single serpentine channel were the highest among all channels. These results can be used to design the PEMFC system, the channel flow field, and the cooling device.     

Analysis of operating characteristics of a polymer electrolyte membrane fuel cell coupled with an air supply system

Balance-of-plant components, especially the air supply system, have a critical impact on the operating condition, performance, and reliability of polymer electrolyte fuel cells (PEMFCs). Thus, we investigated the performance and operating characteristics of a coupled system integrating a PEMFC and an air supply unit. The performance characteristics of the fuel cell stack were modeled using a semi-experimental correlation, and the operating characteristics of a shell-and-tube type membrane humidifier was modeled using heat and mass transfer principles. The models of both components were validated. A turbo-blower determined the condition of the air supplied to the humidifier and its characteristics were modeled using a performance map. A program was developed to simulate the operation of a PEMFC system consisting of the fuel cell stack and the air supply unit, and its operating characteristics at various conditions were investigated. In particular, the effects of operating conditions (ambient temperature and load) on the performance of both the humidifier and the fuel cell stack were examined, and the variations of critical operating parameters were analyzed.     

基于模糊对向传播网络的PEMFC建模

质子交换膜燃料电池是由一种质子导体聚合电解膜构成的燃料电池,作为21世纪的绿色环保能源,对质子交换膜燃料电池进行输出特性研究有助于改善其性能,提高其工作效率。对于这种离散非线性系统,文章将神经网络和模糊控制技术相结合,设计出了一种以模糊神经网络自适应控制系统为核心的建模方法,它是由模糊对向传播（FCP）网络辨识器构成,仿真结果表明该模型可行,而且模型精度较高,从而为设计PEMFC实时控制系统奠定了一定的基础。     

质子交换膜燃料电池密封系统热力耦合仿真研究

温度影响质子交换膜燃料电池（PEMFC）的密封性能和力学行为,因而影响其使用寿命和可靠性。为研究PEMFC在热力耦合下的密封性能和力学行为,建立PEMFC单电池和多电池结构的二维模型,研究密封系统在不同工作温度下的应力-应变分布,讨论橡胶密封圈压缩比、双极板错位和密封垫尺寸对PEMFC密封性能和力学性能的影响。结果表明：温度对密封圈的Mises应力和膜电极组件（MEA）框架接触压力有很大影响;在不同工作温度下单电池和多电池结构的密封性能相似,应力和接触压力分布差别也不大,因此单电池结构的研究结论可以推广到多电池结构;随着橡胶密封圈压缩比和密封圈尺寸的增加,燃料电池密封性能得到改善;而双极板错位会加剧MEA框架的变形;高应力区出现在橡胶密封圈的横截面内部,容易导致局部应力集中和密封失效。     

车用质子交换膜燃料电池动态建模与仿真分析

基于质子交换膜燃料电池（PEMFC）工作机理的分析,考察工作过程中影响其输出特性的5个主要因素（包括理想电动势、欧姆极化电压、活化极化电压、浓度差极化电压和辅助系统电压）,建立了PEMFC的动态数学模型,利用Matlab/Simulink仿真平台对该模型进行了仿真,结果表明,模型输出能有效反映PEMFC的电压输出特性,为PEMFC控制系统的开发奠定了基础。     

Influence of PTFE on electrode structure for performance of PEMFC and 10-cells stack

Water plays a critical role on the performance, stability and lifetime of proton exchange membrane fuel cells(PEMFCs). The addition of poly tetrafluoroethylene(PTFE) to the gas diffusion layer, especially, the cathode side, would optimize the transportation of water, electron and gas and thus improve the performance of the fuel cell. But until now, the studies about directly applying the PTFE to the catalyst layer are rarely reported. In this paper, the membrane electrode is fabricated by using directly coating catalyst to the membrane method(CCM) and applying PTFE directly to the cathode electrode catalyst layer. The performance of the single cell is determined by polarization curves and durability tests. Electrochemical impedance spectroscopy(EIS) and scanning electron microscopy(SEM) techniques are used to characterize the electrochemical properties of PEMFC. Also the performance of a 10-cells stack is detected. Combining the performance and the physical-chemistry characterization of PEMFC shows that addition of appropriate content of PTFE to the electrode enhances the performance of the fuel cell, which may be due to the improved water management. Addition of appropriate content of PTFE enhances the interaction between the membrane and the catalyst layer, and bigger pores and highly textured structure form in the MEA, which favors the oxygen mass transfer and protons transfer in the fuel cell. While superfluous addition of PTFE covers the surface of catalysts and hindered the contact of catalyst with Nafion, which leads to the reduction of electrochemical active area and the decay of the fuel cell performance. The proposed research would optimize the water management of the fuel cell and thus improve the performance of the fuel cell.     

基于磁场的质子交换膜燃料电池故障诊断方法

故障诊断作为解决质子交换膜燃料电池（Proton exchange membrane fuel cell,PEMFC）的安全和寿命问题的重要途径之一,备受研究人员关注。然而在当前PEMFC诊断中,对其早期故障诊断的研究较少,而在亟需早期故障诊断以便及时进行维护控制的PEMFC应用领域,如燃料电池汽车等,在故障发生早期对其进行精确诊断极其重要。该文针对现有PEMFC早期故障诊断方法匮乏问题,提出一种基于磁场的PEMFC故障诊断方法。首先建立PEMFC三维仿真模型,研究燃料电池性能变化与其外部磁场间关联机制,在此基础上搭建燃料电池磁场检测系统,并构建卷积神经网络（Convolutional neural network,CNN）对采集的磁场数据进行分析,验证其在包括水淹、膜干等不同PEMFC故障中的早期诊断效果。结果表明,采用基于磁场数据和卷积神经网络的故障诊断方法,可实现燃料电池不同程度、不同类型故障的在线识别和早期诊断。研究结果验证了磁场数据用于PEMFC故障诊断的可行性,对促进PEMFC故障诊断方法进一步发展、提升PEMFC系统可靠性和耐久性具有重要意义。