Model-based predictive control strategy for a solid oxide fuel cell system integrated with a turbocharger

This paper describes a model-based control design for a solid oxide fuel cell and gas turbine (SOFC/GT) combined cycle system. One-step ahead predictive control is formulated to (1) meet the power demand effectively, (2) handle the multiple constraints of the hybrid system, and (3) minimize the fuel consumption. An SOFC/GT control strategy with two sequential optimization loops is proposed. The primary controller is designed to achieve the system net power, the targeted fuel utilization, and high fuel economy by manipulating the fuel cell current and the anode fuel flow rate. The secondary controller minimizes the fuel cell temperature variation during transients by adjusting the generator load. Simulation results show that the control strategy is capable of achieving fast load transitions while maintaining the fuel utilization within the feasible range. The one-step ahead prediction control is shown to provide the benefits of on-line optimization without incurring large computation burden.