Aiming at adapting to the load fluctuation in power grid

the unit coordinated control(UCC)system frequently regulates the power of each generation unit to ensure the equilibrium and stability of power grid.Thus

the UCC system of a supercritical unit was taken as the research object to conduct investigation on its dynamic characteristics.Through simulation experiment

the response characteristics of two typical UCC strategies to primary frequency regulation and automatic generation control(AGC)were compared.The results showed that

with two different combinations of boiler master control system and turbine master control system

when the dead band and speed drop were constant

the continuous variation of main steam pressure mainly depended on the boiler master control system;when small disturbance occurred

the main factor was the turbine master control system;while in large disturbance condition

the fluctuations of different boiler master control systems' parameters may exceeded the pressure control dead band

causing change of the turbine master control system's outputs

which will affect the system output seriously.