Operation and control of direct reforming fuel cell power plant

Computer simulation is used to analyze the operation and efficiency of a carbonate fuel cell power plant under load perturbations. The plant model is based on a 2 MW system design used in the Santa Clara Demonstration Project and includes: internal reforming carbonate fuel cell stack, cathode gas preparation system, heat recovery unit and fuel processing system. Model development for various processes is based on thermochemical principles and conservation of mass and energy. Overall plant efficiency is determined by net fuel consumption based on calculated gas compositions and auxiliary power consumption. During load maneuvering, several key operational constraints must be maintained. Among these are: allowable stack temperature deviation, baseline fuel utilization, steam/carbon ratio, and pressure difference between anode and cathode. Actual plant control schemes are used in the simulation and are evaluated for performance under load changes. The results of these simulations will be used as a benchmark and development tool for advanced intelligent controllers for autonomous and efficient operation of fuel cell systems