The actual power generating units are often running under variable operating conditions. When the operating condition of the unit changes

the control effect of PID controller parameters set before the working condition changes cannot meet the control requirements under the current working condition

and the regulation ability of the control system is becoming weak. To improve the control quality of the unit under variable working conditions

this paper proposes a PID proportional adaptive active optimization technology in wide load interval. Through zero-crossing judgment logic and selecting and maintaining the maximum/minimum value logic

selfidentifying variable parameters to dynamically modify the proportional parameters of the PID controller

the proportional function of the PID controller is adjusted and optimized online

real-time and dynamically

and the optimal control parameters are automatically searched. This technique is applied to the proportion of boiler master control PID

and the application result shows that

this PID proportion adaptive active optimization technology in wide load range can better adjust the change of main steam pressure

dynamically regulate the proportional parameters

and realize good control of main steam pressure. It can improve the control quality of the controller and enhance the automatic control level of the unit under variable working conditions.