A DYNAMIC MODEL OF THE TURBINE CYCLE OF A POWER PLANT FOR STARTUP (SIMULATION)

A dynamic model of the turbine cycle of a power plant is developed for the study of power plant startup. The model scope is limited to the turbine and feedwater heating systems. Detailed models of heat exchangers are developed that include the effects of energy and mass storage, heat transfer, flooding, incondensable gases and reverse flows. A detailed steam turbine model computes turbine flows based on steam properties and characterized turbine losses. The model is validated with power plant data from startup to fully loaded conditions. Analysis is performed using the model to determine the steady state effects of bypassing feedwater heaters and the transient effects of closing the turbine extractions.; Model validation indicates that the model predicts feedwater heater operation within 10% throughout the load range. The model predicts turbine flows to within 2% at high load levels and 20% at zero load (startup). Steady state analysis indicates that the effects of bypassing individual feedwater heaters are small. Transient analysis indicates that turbine power increases quickly (about 4%) when a high pressure extraction is suddenly closed.