Abstract:

This paper describes the thermodynamic analysis concerned with demonstration how the available range of the capacities of a 370 MW power unit operating in the power and frequency regulation system is affected by the repowering with a gas turbine and a heat recovery steam generator. When the system is not repowered, the capacity of the power unit varies over the entire regulation range, i.e. from 180 to 380 MW, which corresponds to the capacities from the technical minimum determined by the steam boiler to the maximum sustained capacity. The operation of the unit is characterized by the peak load fluctuations, with the lowest load during a night corresponding to the base load demand in accordance with the PPS regulation chart, and the highest load during a day is designed to meet the conditions of the peak demand.