基于误差性能最优的史密斯预估器

Smith Predictor based on optimal error performance

在解决工业流程领域大滞后问题中,传统史密斯预估器PID参数整定不精确,而且传统史密斯预估器无法消除含积分对象稳态误差。为此,提出一种基于误差性能最优PID与史密斯预估控制器结合的策略。首先利用最优控制理论以误差性能为基准设计目标函数、设计提高控制要求的辅助约束条件。其次,在Simulink平台搭建仿真结构,利用线性规划自动计算PID最优参数。为解决含积分对象无法消除误差的问题,使用了一种改进的史密斯预估器结构并且结合误差性能最优PID自整定控制器参数。最后,做了MATLAB仿真实验,获得了较好的控制结果,提高了对滞后的处理效果。

In solving the problem of large lag in the field of industrial process,the PID parameters of the traditional Smith predictor are inaccurate,and the traditional Smith predictor can’t eliminate the steady-state error of the object with integral.Therefore,a strategy based on error performance optimal PID and Smith predictive controller is proposed.Firstly,the optimal control theory is used to design the objective function and auxiliary constraints to improve the control requirements based on the error performance.Secondly,the simulation structure is built on Simulink platform,and the optimal PID parameters are automatically calculated by linear programming.In order to solve the problem that the error of the object with integral can’t be eliminated,an improved Smith predictor structure is introduced,and the PID self-tuning controller parameters are optimized combined with the error performance.Finally,MATLAB simulation experiment is done to obtain better control results and improve the processing effect of lag.