Carbon deposition model of solid oxide fuel cell system for fuel reforming fault prediction

Solid Oxide Fuel Cell (SOFC) is one of the most promising energy conversion technologies due to its high efficiency, low emission, and fuel adaptability. When using natural gas as fuel, a reformer is required to generate hydrogen, which is prone to suffer carbon deposition and even system breakdown due to the operating condition degradation. The phenomenon of carbon deposition process in a SOFC system is subtle and difficult to identify, especially at early stage. Therefore, the analysis and prediction of the carbon deposition fault evolution process are critical for the safe and high-performance operation of SOFC system. In this work, a dynamic SOFC system model that can describe the evolving process of carbon deposition to system fault is established and verified. Firstly, based on a verified high-fidelity Steam Reforming SOFC (SR-SOFC) system model, a dual-process model of the reformer under carbon deposition is incorporated: the first process is to calculate the theoretical maximum output of the reformer based on Gibbs free energy minimization, and the second is to calculate the actual output of the reformer based on the influence of the current carbon deposition. Then, the reformer model is verified with experimental data under the operating conditions of carbon deposition and no carbon deposition. This work lays a foundation for the following system fault prediction research.