Abstract: Dynamic model of the condensate flow and load of ultra supercritical units was given. Reasonable inference and simplified were made by the conservation of volume, conservation of mass and conservation of energy and dynamic model of the condensate flow and load of supercritical units was offered, which could provide theoretical basis for the implement of the power plant condensate throttling and load control. Taking a 1000 MW ultra supercritical unit as an example, simulation of the model was made and compared. Results show that the gain coefficient and the time constant of the transfer function of the condensate flow and load can be regulated by changing different amount of condensate flow at the rated working condition; in different working condition, the gain coefficient is larger with the increase of load, but the time constant is shorter.

Key words: ultra supercritical, condensate throttling, dynamic model, thermal balance diagram, simulation