Research On Practical Predictive Control Strategy Of Superheated Steam Temperature System

The overheating steam temperature system is a highly inertia,a large delayed time-variable system,and in practice,it is more complicated to make the system more complicated,and it is often difficult to obtain a good control effect,so the superheated steam temperature controlled object characteristics is of great significance.The prediction control has been favored by the field of industrial process control since the emergence of industrial process control.It has a unique algorithm advantage,and it can achieve very excellent control effect in some complex control systems,one of which is widely used in the dynamic matrix control(DMC)algorithm.The Siemens S7-300 series PLC is the mainstream small and medium-sized PLC of the industrial application,which has many advantages such as strong versatility,simple programming and convenience of removing maintenance.These advantages make PLC occupy an important position in industrial control.In response to the above,this paper uses an overheating steam thermal system as the research object,and the application technology of predictive control strategies.(1)By studying the characteristics of overheating steam temperature,system identification is performed,identifying data by adjusting the amount of disturbance experiment and set value disturbance experiment,the algorithm is highly recognized;(2)The modified particle group algorithm is used to perform the string PID parameters,compared with the routine empirical method,under the action of the controller parameters obtained by the algorithm,and the system has achieved good control.(3)Basic research on the DMC algorithm,and is applied to the overheating steam temperature stringage control system to achieve a good control effect.In order to further enhance the adaptability of the DMC algorithm on load changes,this paper proposes a DMC improvement algorithm based on parameter optimization scheduling.The algorithm is introduced into a typical model group,according to the degree of matching of the actual output of the typical model,select the corresponding DMC parameter.As the actual DMC controller parameter,the simulation results show that the algorithm can achieve better control effect compared to the conventional DMC algorithm and the cascade PID;(4)Compute the DMC algorithm block in the PLC,built overheating steam temperature virtual objects in DCS Ovation;PLC and DCS implement signal transmission through the Modbus and OPC communication protocols.Constructing a PLC-DCS control algorithm verification platform,and the co-adjustment experiment proves that the DMC algorithm is successfully implemented in the PLC and can achieve satisfactory control.