Analysis of Variation in Steam Turbine Time Constant on Dynamic Frequency Regulation of a Deregulated Power System

At present, increase in renewable penetration has paved the way for the shutdown of existing thermal power plants. This forced system operator, to operate remaining thermal power plants mostly around 70 % to 90 % of its generation schedule. In this paper, effect of varying steam turbine time constant on a re-heater based two-area thermal power system under deregulated environment is analysed. The analysis has been carried out for different scheduled power output of the plant, such as 100 %, 90 %, 70 % and 50 %. The steam turbine time constants for each generation schedule is determined and simulations were carried out for three scenarios, such as unilateral, bilateral and a case of contract violation. In each case, four generation schedule mentioned earlier is taken into account. A comprehensive study was done by analysing all the aspects of a deregulated two area reheater based thermal power system, considering various generation schedules.