Part-load, startup, and shutdown strategies of a solid oxide fuel cell-gas turbine hybrid system

Abstract

Current work on the performance of a solid oxide fuel cell (SOFC) and gas turbine hybrid system is presented. Each component model developed and applied is mathematically defined. The electrochemical performance of single SOFC with different fuels is tested. Experimental results are used to validate the SOFC mathematical model. Based on the simulation model, a safe operation regime of the hybrid system is accurately plotted first. Three different part-load strategies are introduced and used to analyze the part-load performance of the hybrid system using the safe regime. Another major objective of this paper is to introduce a suitable startup and shutdown strategy for the hybrid system. The sequences for the startup and shutdown are proposed in detail, and the system responses are acquired with the simulation model. Hydrogen is used instead of methane during the startup and shutdown process. Thus, the supply of externally generated steam is not needed for the reforming reaction. The gas turbine is driven by complementary fuel and supplies compressed air to heat up or cool down the SOFC stack operating temperature. The dynamic simulation results show that smooth cooling and heating of the cell stack can be accomplished without external electrical power.

Keywords

solid oxide fuel cell (SOFC) / hybrid system / part-load strategy / startup / shutdown

References

[1] US DOE. Fuel Cell Handbook. 7th ed. DOE/NETL., Morgantown, WV, 2004

[2] Park S K, Kim T S. Comparison between pressurized design and ambient pressure design of hybrid solid oxide fuel cell–gas turbine systems. Journal of Power Sources, 2006, 163(1): 490–499

[3] Palsson J, Selimovic A, Sjunnesson L. Combined solid oxide fuel cell and gas turbine systems for efficient power and heat generation. Journal Power source, 2000, 86(1,2): 442–448

[4] Laxmidhar Besra, Charles Compson, Meilin Liu. Electrophoretic deposition on non-conducting substrates: the case of YSZ film on NiO–YSZ composite substrates for solid oxide fuel cell application. Journal Power Souce, 2007, 173(1): 130–136

[5] Aguiar P, Adjiman C S, Brandon N P. Anode-supported intermediate temperature direct internal reforming solid oxide fuel cell. I: model-based steady-state performance. Journal of Power Sources, 2004, 138(1, 2): 120–136

[6] Campanari S, Iora P. Definition and sensitivity analysis of a finite volume SOFC model for a tubular cell geometry. Journal of Power Sources, 2004, 132(1,2): 113–126

[7] Augiar P, Adjiman C S, Brandon N P. Anode-supported intermediate temperature direct internal reforming solid oxide fuel cell. I: model-based steady-state performance. Journal of Power Sources, 2004, 138(1,2): 120–136

[8] Achenbach E. Three-dimensional and time-dependent simulation of a planar solid oxide fuel cell stack. Journal of Power Sources, 1994, 49(1-3): 338–348

[9] Kays W M, London A L. Compact Heat Exchanger. 3rd ed. New York: McGraw Hill Book Company, Inc, 1998

[10] Palsson J, Selimovic A, Sjunnesson L. Combined solid oxide fuel cell and gas turbine systems for efficient power and heat generation. Journal of Power Sources, 2000, 86(1-2): 442–448

[11] Park S K, Kim T S. Comparison between pressurized design and ambient pressure design of hybrid solid oxide fuel cell–gas turbine systems. Journal of Power Sources, 2006, 163(1): 490–499

[12] Chan S H, Low C F, Ding O L. Energy and exergy analysis of simple solid-oxide fuel-cell power systems. Journal of Power Sources, 2002, 103(2): 188–200

[13] Stiller C, Thorud B, Bolland O, Kandepu R, Imsland L. Control strategy for a solid oxide fuel cell and gas turbine hybrid system. Journal of Power Sources, 2006, 158(1): 303–315

[14] Liu A, Weng Y. Performance analysis of a pressurized molten carbonate fuel cell/micro-gas turbine hybrid system. Journal of Power Sources, 2010, 195(1): 204–213

[15] Calise F, Dentice d’Accadia M, Vanoli L, von Spakovsky M R. Single-level optimization of a hybrid SOFC–GT power plant. Journal of Power Sources, 2006, 159(2): 1106–1185

[16] Kandepu R, Imsland L, Foss B A, Stiller C, Thorud B, Bolland O. Modeling and control of a SOFC-GT-based autonomous power system. Energy, 2007, 32(4): 406–417

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Higher Education Press and Springer-Verlag Berlin Heidelberg