Research And Implementation Of PID And MPC Controller Performance Evaluation And Optimization Method

Controller performance evaluation and parameter optimization are the basic means of controller health maintenance.When the controller cannot meet the benchmark requirements,it is necessary to apply the optimization method to the controller to restore the control system to a stable,safe,and efficient state.At present,there is still no integrated software or system with universal appraisal methods and optimization algorithms in the project.Based on this,considering the wide application of DCS in industrial sites and the convenience of MATLAB in analysis,identification and optimization,this research combines the performance evaluation and optimization methods of the controller with the system technology implementation,and the PID is developed under this framework And MPC-based controller performance evaluation and parameter optimization research,and implemented through the interaction of DCS and MATLAB,the main work is as follows:1)Research on PID controller performance evaluation and optimization methodFor the PID loop in the actual industry,the performance of the PID controller is first evaluated based on the minimum variance evaluation method.The output variance under the minimum variance controller of the system is compared with the actual output variance to determine the actual operating state of the controller;then,For PID controllers with poor performance,an alternating generalized least squares method is used to identify the parameters of the model of the controlled object of the current system to confirm that the model parameters caused by the dynamic characteristics change due to long-term operation are perturbed,and then based on The improved bird swarm optimization algorithm is proposed to optimize the parameters of the current controller,and the controller after parameter optimization is again evaluated using the minimum method evaluation method to ensure that the performance of the controller lacking real-time adjustment is improved;finally,pass Simulation cases verify the feasibility and effectiveness of the proposed algorithm,and provide a more realistic theoretical basis for the implementation of PID controller performance evaluation and optimization technology in actual DCS.2)Research on MPC controller performance evaluation and optimization methodAfter the PID controller runs stably,the MPC controller is then considered.In this paper,the minimum entropy control and minimum variance control methods are analyzed in detail,and a double benchmark evaluation method is proposed;then theQDMC algorithm based on the improved bird swarm algorithm is proposed in this paper.Optimize the control rate of the controller.When the controller is perturbed due to the parameters,which leads to a large drop in performance,first identify the system parameters,and secondly,based on the DMC method based on improved bird swarm,from the perspective of the operator and engineer Carry out optimization,change the controller parameters by changing the softening coefficient,prediction step and control step,and finally verify the effectiveness of each algorithm through secondary evaluation,which provides real-time performance evaluation and optimization of MPC controller in actual DCS A more reasonable theoretical method.3)Controller performance evaluation and optimization platform design and developmentOn the basis of verifying the above research methods at the theoretical level,first of all,a brief introduction to the controlled object,and second,a detailed demonstration of the system plan;then the DCS comes with software to discuss how DCS interacts with Matlab and how the data To achieve interoperability,then design and implement the human-computer interaction interface of the PID controller and MPC controller,and finally encapsulate the GUI interface,independently into software,in order to facilitate the actual project.