Validated combined cycle power plant model for system and station performance studies

Validated simulation models of power plants are now frequently requested as part of the requirement for grid code compliance. This paper presents the development of a simulation model of a new 650 MW multishaft combined cycle power plant, located in Malaysia as part of the abovementioned compliance issue. The power plant model comprises of detailed simulation models of the major equipment enabling system and plant dynamic performance studies to be carried out. These models can provide detailed electrical as well as physical information related to the generator, excitation system, gas turbine, steam turbine, heat recovery steam generator and associated controls. In order to access the physical information of the gas turbine such as outlet temperature, fuel mass flows etc., a physical model of the gas turbine and a replica of the relevant gas turbine control system have been developed. The simulation platform for these models is a dynamic simulation program for power systems, widely used by electrical utilities. Site tests and measurements were used to obtain the correct parameters and further validate these models. Validation of these models through comparison of the simulated results with recorded measurements of site tests provides added confidence when using these models to investigate the response of the combined cycle power plant during system disturbances, such as severe frequency variations.