Simulation und Analyse des dynamischen Verhaltens von Kraftwerken mit oxidkeramischer Brennstoffzelle (SOFC)

Finkenrath, Matthias

Dissertation / PhD Thesis/Book

Simulation und Analyse des dynamischen Verhaltens von Kraftwerken mit oxidkeramischer Brennstoffzelle (SOFC)

Finkenrath, M. (Corresponding author)FZJ*

2005
Forschungszentrum Jülich Gmbh Zentralbibliothek, Verlag Jülich
ISBN: 3-89336-414-5

Jülich : Forschungszentrum Jülich Gmbh Zentralbibliothek, Verlag, Schriften des Forschungszentrums Jülich. Reihe Energietechnik / Energy Technology 44, IV, 156 S. (2005) = RWTH Aachen, Diss., 2005

This record in other databases:

Please use a persistent id in citations: http://hdl.handle.net/2128/544

Abstract: Solid oxide fuel cell (SOFC) systems are especially advantageous for a highly efficient and lowemission energy supply. Due to the very limited operating experience with this fuel cell type, the aim of this work is the development of a generalized dynamic system simulation for SOFC power plants. In this way, interactions between subsystems can be analysed before system operation, and resource-saving operating strategies can be developed. The system simulations presented in this work are based on a common generic modelling concept for all process units. The modelling details are derived from the existing components of a 20 kW fuel cell system, which is currently under construction at Forschungszentrum JÜlich. Numerous measurement data are therefore available, and are used to thoroughly validate all component models. This work is focused on dynamic simulation results for all operating conditions such as heat-up, start-up, nominal and part-load operation as weil as shutdown. Operating strategies are thus optimized regarding energy and time requirements. For the SOFC system analysed, simulated heat-up times from room temperature to 600°C are ab out five hours under the given constraints. Subsequent electrochemical start-up to nominal load takes an additional hour. As the analysis shows, both load reduction as weil as load increase can be performed rapidly if the system is close to its operating temperature. Stable SOFC system operation is possible even at low current densities. Heat input to keep the system on temperature is only required in the case of several hours of pure stand-by operation. During shutdown, all system components can be brought back to room temperature within a day if a high cooling flow is used. The simulations are carried out for an SOFC system with separate steam production for the reforming unit. Simulation of an additional system configuration, where anode off-gas is recycled, shows the possibility of a further increase in overall system efficiency.

Classification: