Proton Exchange Membrane (PEM) fuel cells offer high efficiency and low emissions and have become popular as an alternate power source for various applications. Researchers in various countries have focused on improving the performance and reducing the cost of PEM fuel cell stacks for many years. But with the improvement of the performance and extension of the market of PEM fuel cells, research on highly effective control methods has become an urgent task. The flow control system is very important to the PEM fuel cell and extensive research on it is of great significance in both theory and practice. Main work and contributions in this dissertation are described as follows. Firstly, a practical PEM fuel cell power system is established, which consists of fuel cell stack, gas supply subsystem, temperature and humidity subsystem, power management subsystem and control subsystem. It provides a PEM fuel cell test bench for our research. Secondly, a system level dynamic model of a PEM fuel cell is established by combing the experimental data with the principal laws of correlative subjects. The model includes the fuel cell stack model, compressor model, cathode and anode flow system model, humidity subsystem model and power management subsystem model. The dynamics included in the model are PEM fuel cell current and stack volt dynamics and flow and pressure dynamics of the cathode and anode gas manifold. Thirdly, we integrate and validate the model established with the experimental data. With the MATLAB tools, we make the simulation experiments and compare the simulation results with experimental results, which validate the model. Fourthly, according to the established flow system dynamic model, a controller is designed to realize different flow and pressure control objectives of the startup and working stage of the PEM fuel cell. The control results are satisfactory. Finally, a novel NetCon controller based on an ARM microprocessor and visual supervisory and control configuration software is applied to the data collection and control of the fuel cell system. The experimental results shows that the controller is applicable for the control of the fuel cell system.
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