| Along with the rapid development of global economy, we are facing the increasingly serious energy crisis and environmental pollution problems. It has become one of the important topics to develop a new environmental-friendly energy utilization technology for countries in the world. As a new mobile and fixed power generation technology, the proton exchange membrane fuel cell (PEMFC) has received worldwide attention. PEMFC is a device that can directly convert the chemical energy contained in the fuels and oxidant to electrical energy. It has been widely used as vehicle power and distributed power household source because of its low working temperature, low noise, high efficiency and zero emission.It is necessary to develop a PEMFC system model and conduct simulation analysis in order to provide theoretical guidance and technical support for its practical applications; on the other hand, it is a key issue to develop a more accurate mathematical model, because the accuracy of mathematical model directly affects the application value of simulation results.The characteristics and classifications of the fuel cells are briefly summarized, the prospects of the future development are mentioned, and the working principle of PEMFC is briefly introduced. The research direction is oriented based on the mathematical model for PEMFC.A steady, lumped-parameter mathematical model for single cell is established by empirical modeling method. The three-dimensional relationship diagram of working temperature, current density and the output parameter is also investigated. According to the diagram, the influence that working parameters (such as reaction temperature, gas pressure and current density) made on PEMFC performance is further analyzed.A PEMFC model considering the unsteady water transmission is established based on the steady-state lumped-parameter model, electrochemical model and water transport model according to principle of conservation of energy, mass and momentum. The effects of load step change on output voltage, power and efficiency are also investigated under the uniform pressure and temperature. From the simulation results, we found that the power output range was more appropriate and stable when PEMFC worked in ohm polarization area.Considering some factors of cell temperature, gas pressure and the flow, dynamic response of the various output parameters such as the output voltage, temperature, pressure and flux of reaction is analyzed. We found that it is necessary to cool PEMFC in order to make the best performance and improve the service life.The impact of pressure, flow, membrane water transmission speed, quality and the relative humidity on the dynamic response is described, and the reason of relative humidity on the dynamic response under load step condition is analyzed. Because of the instruction of the water transmission model, our model developed in this dissertation has more accuracy compared to other unsteady and only considering reaction gas heat and mass transfer models. And it is a very powerful tool to the real-time control and optimization design of PEMFC.
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