Thermal modeling of a solar steam turbine with a focus on start-up time reduction
2012 (English)In: Proceedings of the ASME Turbo Expo 2011, Vol 3, 2012, 1021-1030 p.Conference paper (Refereed)
Steam turbines in solar thermal power plants experience a much greater number of starts than those operating in base-load plants. In order to preserve the lifetime of the turbine whilst still allowing fast starts, it is of great interest to find ways to maintain the turbine temperature during idle periods. A dynamic model of a solar steam turbine has been elaborated, simulating both the heat conduction within the body and the heat exchange with the gland steam, main steam and the environment, allowing prediction of the temperatures within the turbine during off-design operation and standby. The model has been validated against 96h of measured data from the Andasol 1 power plant, giving an average error of 1.2% for key temperature measurements. The validated model was then used to evaluate a number of modifications that can be made to maintain the turbine temperature during idle periods. Heat blankets were shown to be the most effective measure for keeping the turbine casing warm, whereas increasing the gland steam temperature was most effective in maintaining the temperature of the rotor. By applying a combination of these measures the dispatchability of the turbine can be improved significantly: electrical output can be increased by up to 9.5% after a long cool-down and up to 9.8% after a short cool-down.
Place, publisher, year, edition, pages
2012. 1021-1030 p.
Average errors, Dispatchability, Effective measures, Electrical output, Heat exchange, Solar thermal power plants, Startup time, Steam temperature, Thermal modeling, Turbine casing
IdentifiersURN: urn:nbn:se:kth:diva-35272DOI: 10.1115/GT2011-45686ISI: 000320967100101ScopusID: 2-s2.0-84855880509ISBN: 978-0-7918-5463-1OAI: oai:DiVA.org:kth-35272DiVA: diva2:426484
ASME 2011 Turbo Expo: Turbine Technical Conference and Exposition, GT2011; Vancouver, BC; Canada; 6 June 2011 through 10 June 2011
QC 201106282011-06-282011-06-232014-09-01Bibliographically approved