Gas turbine combined cycle start-up and stress evaluation: A simplified dynamic approach

Abstract The main topic of this work is the development and validation of a simplified approach for the dynamic analysis of a Gas Turbine Combined Cycle (GTCC), with a particular focus on start-up procedure and associated mechanical stresses on the steam turbine (ST). The currently deregulated energy market led GTCC to undergo frequent startups, a condition often not considered during plant design. Moreover, the time required for the start-up is crucial under an economical viewpoint, though it is constrained by mechanical stresses imposed to thick components by thermal gradients. The framework proposed in this work aims to improve the accessibility to simulation software by applying commonly used office suite – Microsoft Excel/Visual Basic – with acceptable reduction in accuracy. Simplicity of model allow fast computation and its exploitation can be pursued by non-qualified plant operators. The obtained tool can be than adopted to support decision process during plant operations. The developed tool has been validated for a hot start-up against field measurements supplied by Tirreno Power S.p.A. Italy. Data are recorded through control and monitoring sensors of a 390 MW multi-shaft combined cycle based on the GT AEN94.3 A4 frame, but the results can be easily generalized to other layouts. Simulation result and stress evaluations around the steam turbine (ST) rotor show good agreement with experimental data.

[1]  Fast cycling and rapid start-up : new generation of plants achieves impressive results , 2022 .

[2]  Bandar Jubran Alqahtani,et al.  Integrated Solar Combined Cycle Power Plants: Paving the Way for Thermal Solar , 2016 .

[3]  Jochen Ströhle,et al.  Modeling and investigation start-up procedures of a combined cycle power plant , 2008 .

[4]  Francesco Casella,et al.  Fast Start-up of a Combined-Cycle Power Plant: a Simulation Study with Modelica , 2006 .

[5]  Daniel Bouskela,et al.  Dynamic modelling of a combined cycle power plant with ThermoSysPro , 2011 .

[6]  S. Can Gülen,et al.  Second Law Efficiency of the Rankine Bottoming Cycle of a Combined Cycle Power Plant , 2008 .

[7]  Alberto Mirandola,et al.  Dynamic behaviour analysis of a three pressure level heat recovery steam generator during transient operation , 2015 .

[8]  Jochen Ströhle,et al.  Dynamic simulation of a supercritical once-through heat recovery steam generator during load changes and start-up procedures , 2009 .

[9]  Alberto Traverso,et al.  FIELD MEASUREMENT RECONCILIATION FOR COMBINED CYCLE HEAT RECOVERY STEAM GENERATOR MONITORING , 2014 .

[10]  Didier Dumur,et al.  An optimization procedure of the start-up of Combined Cycle Power Plants , 2011 .

[11]  Machteld van den Broek,et al.  Operational flexibility and economics of power plants in future low-carbon power systems , 2015 .

[12]  Roberto P. Razzoli,et al.  Influence of Start-up Management on the Residual Life of a Large Steam Turbine Shaft , 2016 .

[13]  Ashok Rao,et al.  An evaluation of advanced combined cycles , 2013 .

[14]  Afshin Ebrahimi,et al.  Exergoeconomic analysis and optimization of a triple-pressure combined cycle plant using evolutionary algorithm , 2015 .

[15]  Mohsen Assadi,et al.  An EU initiative for future generation of IGCC power plants using hydrogen-rich syngas: Simulation results for the baseline configuration , 2012 .

[16]  Didier Dumur,et al.  Design of a combined cycle power plant model for optimization , 2012 .

[17]  Shankar Narasimhan,et al.  Data reconciliation & gross error detection: an intelligent use of process data , 1999 .

[18]  Ali Ghaffari,et al.  Thermodynamic modeling based optimization for thermal systems in heat recovery steam generator during cold start-up operation , 2014 .

[19]  S. Can Gülen,et al.  Gas Turbine Combined Cycle Dynamic Simulation: A Physics Based Simple Approach , 2013 .

[20]  R. Kehlhofer,et al.  Combined-cycle gas and steam turbine power plants. 2. edition , 1991 .

[21]  Alberto Traverso,et al.  Heat Recovery Steam Generator Health Assessment Basing on Reconciled Measurement , 2014 .

[22]  Didier Dumur,et al.  Optimization of the combined cycle power plants start-up , 2011 .

[23]  F. Carl Knopf,et al.  Enhanced turbine monitoring using emissions measurements and data reconciliation , 2016 .

[24]  P J Dechamps,et al.  Modelling the Transient Behaviour of Heat Recovery Steam Generators , 1995 .

[25]  Dejan M. Mitrović,et al.  Computation of Working Life Consumption of a Steam Turbine Rotor , 2010 .

[26]  J. Warner,et al.  Combined - Cycle Gas & Steam Turbine Power Plants , 1999 .

[27]  Janusz Kotowicz,et al.  The characteristics of ultramodern combined cycle power plants , 2015 .

[28]  Igor Bulatov,et al.  Application of optimal design methodologies in retrofitting natural gas combined cycle power plants with CO2 capture , 2016 .

[29]  Stefano Bracco,et al.  Dynamic simulation of combined cycle power plant cycling in the electricity market , 2016 .

[30]  Bernd Epple,et al.  Comparative investigation of drum-type and once-through heat recovery steam generator during start-up , 2015 .

[31]  Bernd Epple,et al.  Numerical and experimental study of a heat recovery steam generator during start-up procedure , 2014 .

[32]  Alberto Traverso,et al.  A Simplified Hybrid Approach to Dynamic Model a Real HRSG , 2015 .