Global self-optimizing control of a solid oxide fuel cell

The implementation of a well-designed control structure is crucial for efficient and optimal functionality of solid oxide fuel cells (SOFCs). In this work, we propose a self-optimizing control (SOC) solution for a direct internal reforming SOFC, with the objective of maximizing the power generation profit after deducting carbon tax. Based on the SOC methodology, we identify optimal controlled variables (CVs) for the SOFC, which are maintained at constant setpoints to optimize the efficiency, regardless of changes in interference and uncertain parameters. Studies show that the stack temperature is the active constraint which is constrained at the upper bound. Besides, we configure the linear combination of outlet hydrogen fraction, carbon dioxide fraction and voltage as an additional CV to achieve acceptable efficiency loss. The effectiveness of the novel SOC scheme is verified through both steady state and dynamic simulations.