| A sixty-fifth order, nonlinear dynamic model of a 235 MW natural gas fired power plant was developed. Twenty states describe the thermal-fluid processes and forty five states describe the control systems. The model includes all the major process components and the control system loops required for the normal operation of the plant. The process' governing equations are derived from physical conservation laws with process parameters computed from construction drawings, material properties, and plant data. The control system models are derived from circuit diagrams with control parameters computed from resistive and capacitive values of the components. The model is validated with actual plant data from a Linear Operation Test run in September, 1980. The model is intended to help the plant engineer predict plant behavior under steady state and transient operations and to be used in control system and operational optimization studies. The model was used to investigate the irreversible losses caused by small amplitude oscillations of load demand when the plant is in cycling duty. It was also used to investigate the irreversible losses in the daily load cycle from minimum overnight to maximum load during the day. Other applications included a study of the effect of fluid transport time delays in the plant simulation, a study of the tuning of the load dispatch control system, and a study to validate and interpret results of a previous study on the plant fuel optimization. |
