University of Genoa has been involved in the development of modelling tools for Rolls-Royce Fuel Cell Systems Ltd in the last few years. On-design, off-design and time-dependent models have been generated for several system components (e.g.: turbomachinery, ejector, fuel cell, reformer, etc.).This work presents the development of generic time-dependent simulation tools of SOFC gas turbine hybrid systems, for control and monitoring purposes. The applications are fourfold:1) to develop, optimise and tune the control system2) to test the control system in software-in-the-loop configuration3) to test the actual controlling hardware in hardware-in-the-loop configuration4) to monitor and diagnose the actual system during operationThe third and fourth applications also require outcoding and real-time capabilities. In fact, the newly developed models of the whole hybrid system can run several time faster than real-time on a modern laptop. Real-time modelling is a recognised approach to monitor advanced systems and to improve control capabilities: applications of real-time models are commonly used in the automotive and aircraft fields.With regard to such existing applications, SOFC hybrid system presents a number of challenging aspects:-they retain a very high degree of complexity, being composed of a variety of chemical, mechanical and electrical devices, all deeply interconnected: from a mathematical point of view, the modelling problem is highly stiff and non-linear.-they are subject to long lasting transients, which are due to the large thermal capacitance of the fuel cell stack and auxiliary components (reformer, heat exchanger, vessel and insulation, etc.); this fact requires the model to be able to simulate several hours in, possibly, just a few minutes. This is a major difference when compared to simple cycle gas turbines.-chemical composition of flows changes significantly along the reformer and fuel cell paths, thus requiring detailed chemical modelling, with just a few simplifications possible. For comparison, in conventional combustion systems, the change in thermo-physical properties of the exhausts, when compared to combustion air, is often negligible from a thermal balance and mechanical points of view.In this work it is show how, starting from existing TRANSEO components and models, a new approach to fit hybrid system application has been developed. Original C-based models have been translated into embedded Matlab functions for direct use into Matlab-Simulink. Calculation time has been dramatically improved, still retaining acceptable accuracy of the results, as demonstrated by comparison with original TRANSEO model and experimental validation.In the short-term, the generic time-dependent models are being employed for control system development of hybrid system pilot plants (point 1 above), and for verification of the actual control hardware (point 3 above). In the medium-term, the availability of such tools will contribute to the monitoring and diagnostics of pilot plants, and to the optimisation of controllability and load-following capability of SOFC hybrid systems, allowing for significant time and cost savings.
