串级不稳定时滞过程的改进内模控制方法

An Improved Internal Model Control Method for Cascade Unstable Time-Delay Processes

针对串级不稳定时滞过程提出了一种改进的内模控制方法。该方法副回路采用内模控制结构,快速消除副回路干扰对系统的影响;主回路采用基于内模的二自由度控制结构,避免了系统设定值跟随特性和干扰抑制特性折中问题,通过设计PID控制器串联一个超前滞后补偿器来加强干扰抑制特性,利用设定值滤波器来改善系统的设定值跟随特性。仿真结果表明,该方法可使系统同时具有较好的动态响应、干扰抑制特性以及鲁棒性。

An improved internal model control method is proposed for cascade unstable time-delay processes.The internal model control structure is adopted in the secondary loop to eliminate the influence of the disturbance in the inner loop on the system.The two-degree-of-freedom control structure based on the internal model is adopted in the primary loop to avoid the compromise between the set-point tracking characteristic and the disturbance rejection characteristics.A PID controller with an additional Leading-Lag compensator is designed,which can enhance the disturbance rejection characteristics.In addition,the set-point filter is used to improve the set-point tracking characteristics of the system.The simulation results show that this method can make the system have good dynamic response,disturbance rejection characteristics and robustness at the same time.