The design scheme and structure of automatic power plant start-up and shut-down control system(APS)for an ultra supercritical 1 000 MW unit with double-reheat cycle in Taizhou Power Plant was presented.The basic points and attentions during the accomplishment of the APS were introduced

which includes the design of the DCS hardware

device driver level logic

sequence control standard logic and human interface.It pointed out that the key points during the APS design are the superheated steam temperature control

the primary reheate stem temperature control

the secondary reheat steam temperature control and the third bypass control during the start-up and shut-down process of the unit.Moreover

the automatic scheme for the whole process of steam temperature control and bypass control were given.It indicated that the application of the APS reduces the start time and the power consumption rate

improves the economic efficiency

and its design and the function of the break-point

steam temperature and bypass full automatic control have a certain value to other ultra-supercritical units with double-reheat cycle.