Dynamic modelling and control of planar anode-supported solid oxide fuel cell

Most solid oxide fuel cell (SOFC) modelling efforts emphasize steady-state cell operation. However, understanding the dynamic behaviour is essential to predict the performance and limitations of SOFC power systems. This article presents the development of a SOFC dynamic model and a feedback control scheme that can maintain output voltage despite load changes. Dynamic responses are determined as the solutions of coupled partial differential equations derived from conservation laws of charges, mass, momentum and energy. To obtain the performance curve, the dynamic model is subjected to varying load current for different fuel specifications. From such a model, the voltage responses to step changes in the fuel concentration and load current are determined. Low-order dynamic models that are sufficient for feedback control design are derived from the step responses. The development of the partial differential equation model is outlined and the limitations of the control system are discussed.