Due to large delay and inertia of unit control system at the boiler side

the load response time of the conventional coordinated control strategy is usually long and the load change speed is below 2% of the full load in one minute. To solve this problem

this paper proposes a novel load control strategy based on back pressure regulation. On the premise of safe back pressure

this control strategy takes the condenser cooling water flow as a new control variable for the steam turbine load. When the steam turbine load order is changed

the back pressure will be changed immediately to decrease the variance. And when the steam turbine load is close to the load order

the back pressure will be recovered to its normal value to ensure energy-saving and prepare for the next load dispatch. Tests on the simulator show that the condenser back pressure and steam turbine power would arrive at another steady values in 30 seconds after the cooling water flow changed. The static and dynamic models between the cooling water flow and the turbine power were set up based on the mechanism analysis and identification. A novel load-change strategy based on continuous back-pressure regulation was firstly proposed: the back pressure regulation is activated mainly in the initial control period

and the coordinated control is mainly used at the end of the control. Simulation were conducted on a 300 MW coal-fired unit and the results prove that this control strategy shortens the responding time and accelerates the load change speed.