| Fuel Cells (FCs) are electrochemical devices that convert a fuel's chemical energy directly to electrical energy plus heat with high efficiency. With no internal moving parts, fuel cells operate similar to batteries. An important difference is that batteries store energy, while fuel cells can produce electricity continuously as long as fuel and air are supplied.The application of fuel cell technologies to advanced power generation systems implies the most significant advancement in energy conservation and environmental protection for the next decades.In this thesis, a dynamic PEM fuel cell model is constructed using electrical circuits in PSCAD/EMTDC simulator. In this model, the double-layer charging effect and the thermodynamic characteristic inside the fuel cell are both integrated into the model. This fuel cell model is a very important part of the whole fuel cell DG model. It also shows the potential to be useful in other related studies. In order to interface the fuel cell with AC loads and/or the electric grid, a novel DC/DC boost converter with a 1-phase 3-winding high frequency transformer is designed. This novel DC/DC topology provides the fuel cell DG systems with several distinguished advantages. In addition, one 3-phase 4-wire DC/AC SPWM inverter is also designed in order to connect the fuel cell DG to the AC loads and/or the utility grid. Moreover, proper control strategies are also designed for interface operations and different DG operation modes. The DG is simulated both as a stand-alone DG and as a grid connected DG in PSCAD/EMTDC simulator.Furthermore, the PEM fuel cell DG is also economically evaluated under deregulated electricity market. The cost of electricity of the PEM fuel cell DG is calculated. Different operation scenarios are studied and analyzed. Moreover, fuel cell DG as a demand-side management alternative is studied, and the economic benefits are also analyzed.Fuel cells are appealing because they offer high efficiency, excellent part-load performance, low emissions of regulated pollutants, and a wide rate range. Researchers, manufacturers, energy companies, and regulatory agencies are currently working to develop a variety of fuel cell types and to design the infrastructure that will support this important new technology. These efforts involve development of new materials, economical manufacturing processes, advanced equipment for supplying fuel and air, advanced power electronics for controlling the power output, and comprehensive approaches for system analysis and optimization. |
