The Research And Application Of Coordinated Control Strategy For 350MW Supercritical Unit

During the operation of thermal power units,safety and stability are very important.As the most widely used unit at present,the control technology of supercritical units is very important.In order to solve the problem of energy supply and demand balance between the unit and the power grid,the coordinated control system of the unit is worth studying.The control core of the whole unit is the coordination control system.The idea of coordinated control is to control the boiler and steam turbine as a whole,not only to meet the load change requirements of the power network,but also to ensure that the operating parameters of the unit do not produce large fluctuations.It plays a vital role in the safe and stable operation of the unit.To improve the performance of coordinated control system,we can start from improving the controller parameters.PID control is a common controller in power plants.To improve the control quality of PID controller,it is necessary to set the appropriate PID parameters to make its control effect reach the standard.Therefore,the study of PID controller parameter tuning technology has great practical significance.In this paper,the coordinated control system of 350 mw supercritical unit as control object is discussed,the composition and function of the control system of supercritical unit,control mode of coordinated control system are discussed in this paper,in combination with SAMA graph analysis,of a 350 mw supercritical unit coordinated control system of load command loop,turbine master,master,subsystems and the main boiler and steam boiler temperature control system control strategy are analyzed in detail.According to the transfer function of the 350 MW supercritical unit coordinated control system identified in the literature,the control system was simulated by MATLAB software,and on the basis of the establishment of the system simulation model,the influence of the change of the parameters of the controlled object and the change of the regulator parameters on the stability of the system was analyzed.Combined with the simulation results,the tuning results are analyzed,and it is verified that the expert self-tuning PID tuning method has a certain practical application significance in the thermal control system of thermal power plant.