ASPEN dynamics simulation for combined cycle power plant – Validation with hot start-up measurement

Since the beginning of energy market liberalization, shutdown and start-up phases of thermal power plants have acquired greater importance. Dynamic simulation is a helpful tool due to its possibility of predicting the behaviour of the power plant with a good degree of accuracy. This paper goes into the details of the hot start-up phase of a combined cycle power plant with three-pressure level heat recovery steam generator, analysing the capability of the software ASPEN Plus Dynamic through a dynamic comparison between the numerical results and the real operation data. The developed model is built according to the design data of an actual plant including heat exchangers, pipes, turbines, valves, pumps and so on. Good agreements between measurement and simulation results, with some discrepancies in the first phase of the start-up, have been found and then discussed. Best deviation values are obtained for the temperature where the maximum relative error is 3.62% in the re-heater section. Worst deviation values are obtained for the pressure where the maximum relative error shown is 10.8%. Further possible improvements of the model and future applications are suggested.