In order to enhance the deep peak-regulating capacity of ultra-supercritical thermal power units and solve the problem of large capacity units with low efficiency at low load section

the 1 000 MW unit with high efficiency and wide regulation load demonstration project was put forward and constructed. The burner and water wall of the boiler and steam turbine parameters were applied to the optimization design. The model and operation mode of water supply pumps

condensate pumps

circulating pumps and other auxiliary equipment were optimized. By adding a supplementary steam valve

an external cooler

No.0 high pressure heater

low temperature economizer and other equipment

the unit still maintain a relatively high efficiency in a wide range of target load. The thermal calculation results show that the efficiency of the demonstration unit is 3% higher than the existing unit at 50% load

and the operation flexibility of the demonstration unit has been significantly enhanced

which has made obvious economic and social benefits. The related experience has a reference value for the subsequent similar units to enhance their flexibility.