Model Development and Simulation of Transient Behavior of Heavy Duty Gas Turbines

This paper describes models for a transient analysis of heavy duty gas turbines, and presents dynamic simulation results of a modern electricity generation engine. Basic governing equations are derived from integral forms of unsteady conservation equations. Mathematical models of each component are described with the aid of unsteady one-dimensional governing equations and steady state component characteristics. Special efforts have been made to predict the compressor characteristics including the effect of movable vanes, which govern the running behavior of the whole engine. The derived equation sets are solved numerically by a fully implicit method. A controller model that maintains constant rotational speed and target temperature (turbine inlet or exhaust temperature) is used to simulate real engine operations. Component models, especially those of the compressor, are validated through a comparison with test data. Simulated is the dynamic behavior of a 150MW class engine. The simulated time-dependent variations of engine parameters such as power, rotational speed, fuel, temperatures and guide vane angles are compared with field data. Simulated results are fairly close to the operation data.