Modeling and simulation of dynamic characteristics, a membrane fuel cell for proton exchange

In order to investigate the output characteristic of a proton exchange membrane fuel cell (PEMFC) based on the electrical empirical model, a novel dynamic model of the PEMFC has been developed with MATLAB/Simulink, which is distinct from the models that have been published previously. By using a fuel cell test system of the Fuel Cell Application Centre (FAC) at Temasek Polytechnic, the transient electrical responses of PEMFC were conducted and analyzed under various operating conditions. A good match is found between simulation results and experimental data.This model will be very useful to optimize the structure design, improve the operation performance, and develop the real-time control system of PEMFC.WITH the world facing the global warming problem, fuel cells are one of the promising energy technologies for sustainable future due to their high energy efficiency and environment friendliness. Compared with the other types of fuel cells, a proton exchange membrane fuel cell (PEMFC) shows promising results with its advantages such as low temperature, high power density, fast response, and zero emission if it is run with pure hydrogen. For a better understanding of the characteristics and evaluation of the performance of PEMFCs, and therefore, optimization of a fuel cell system, numerous authors have developed various models [۱]–[۸]. The earlier works stem from Bernadi and Verbrugge [۱], who developed ۱-D, isothermal models of the membrane electrode assembly (MEA). Fuller and Newman [۲] published a quasi-۲-D model based on concentration theory. Amphlett et al. [۳] developed an electrochemical model for a Ballard Mark V ۳۵-cell ۵-kW PEMFC stack by performing mass and energy balances on the stack. Baschuk and Li [۴] formulated a mathematical model for the performance and operation of a single polymer electrolyte membrane fuel cell, which incorporates all the essential fundamental physical and electrochemical processes occurring in themembrane electrolyte, cathode catalyst layer, electrode backing, and flow channel. Maggio et al. [۵] proposed a mathematical simulation model to describe the water transport in proton conductive membranes.The novel modeling work was started by Yerramalla et al. [۶], who developed a mathematical model for investigating the dynamic performance of a PEMFC; this model is based on physical laws having clear significance in replicating the fuel cell system and can easily be used to set up different operational strategies. From the empirical point of view, Busquet et al. [۷] formulated a model that enables simulation of the V –I curve (cell voltage versus current density) of both fuel cells and electrolyzers in typical conditions. Different from the normal PEMFC model. are not verified by experimental data. In this paper, the MATLAB/ Simulink tools based on the obvious mathematical model of PEMFC are used to establish a simple and effective dynamic PEMFC model through which the behaviors of the transient voltage, power, and efficiency of the PEMFC with changing load are analyzed. Meanwhile, the dynamic electrical response of the PEMFC was tested by fuel cell test system ۸۹۰ CL incorporating.The comparison of the test results and the modeling simulation results show that the model can effectively predict and evaluate the characteristics of the fuel cell, and it can be helpful for the system analysis, design optimization, and real-time control of the PEMFCs.PEMFC is a nonlinear, multiple-input and -output, strongly coupled, and large-delay dynamic system, the working process of which is accompanied with liquid/vapor/gas mixed flow trans portation, heat conduction, and electrochemical dynamical reaction. Hydrogen The work process and reaction principle are shown in Fig. ۱. Platinum catalyst is used to speed up the electrochemical reaction on both anode and cathode. Hydrogen atoms are stripped of their electrons, or “ionized,” at the anode. At the cathode, the electrons, hydrogenprotons, and oxygen from the air combine to form water [۷]–[۸].Fig ۲. Module diagram of the PEMFC dynamic model by Simulink.In this paper, a dynamic model of PEMFC, which has been implemented in MATLAB/Simulinkenvironment, is proposed. A series of simulation and analyses is carried out, which includes the voltage,power, and efficiency of the PEMFC with changing load. The comparison between the experimental dataand simulation results shows that the model developed is valid and operable, and reflects the dynamicoutput characteristic of the PEMFC. The analyses demonstrate that the dynamic interaction effects withinPEMFC are significant and necessary. It can also effectively predict and evaluate the performance of thefuel cell. Further improvement of the model would be helpful for the performance analysis, designoptimization, and real-time control

کلیدواژه ها:

Dynamic model ، dynamic simulation ، proton exchange membrane fuel cell (PEMFC) ، transient electrical response