针对大时滞过程下的改进内模控制方法研究

Research on Improved Internal Model Control Method for Large Time-delay Process

针对工业过程中较难控制的大滞后系统,提出了一种改进内模控制方法。该方法首先引入滞后时间削弱环节来降低滞后对系统的影响,然后在设定值之后增加导引过渡过程解决系统快速性与超调之间的矛盾,最后再基于内模控制的原理设计控制器。该方法解决了传统Smith预估控制等方法在被控对象模型预估不准确的情况下很难取得较好控制效果的问题,并且在大时滞过程下较双口内模控制等改进内模具有更好的控制效果。最后将该方法与PID-Smith预估控制以及双口内模控制的控制效果进行对比。仿真结果表明,该控制方法可以有效地改善大滞后对象的控制效果,提高了系统的鲁棒性和抗干扰特性。

For large time-delay systems that are difficult to control in the industrial process,an improved internal model control method is proposed.The influence of time-delay on the system is reduced by introducing a time-delay weakening link,and the guidance transition process is added after the set value to resolve the contradiction between the rapidity and overshoot of the system,and then the controller is designed based on the principle of internal model control.This method solves the problem that the traditional Smith predictive control and other methods are difficult to obtain better control effect when the controlled object model is not accurate.And in the process of large time-delay,the improved internal model has better control effect than the double-port internal model control.In the end,the control effect of this method is compared with that of PID-Smith predictive control and the double-port internal model control.The simulation results show that the method can effectively improve the control effect of large time-delay objects,and improve the robustness and anti-interference characteristics of the system.