一种积分时滞过程的内模PID鲁棒整定方法

IMC-PID robust tuning method for integrated process with time-delay

针对工业系统中普遍存在的积分时滞过程,提出了一种内模PID(比例-积分-微分)控制器设计及鲁棒整定方法.利用一阶环节逼近积分环节,改善了内模控制系统的稳态特性,在此基础上利用一阶泰勒表达式逼近过程模型中的时滞项,得出了内模PID控制器的设计方法,并根据最大灵敏度Ms指标,导出了对控制器可调参数进行鲁棒整定的解析表达式,克服了常规方法中参数整定的盲目性.仿真结果表明该方法可使系统同时获得良好的动态响应性能和鲁棒性.

For the integrated plus time delay in industrial system,a design and parameters tuning approach of internal model control-proportional integral derivative（IMC-PID） controller was proposed.Replacing the integrator in the model by a first-order lag,the steady-state performance of the system was improved.On this basis,the time-delay term in the model was approached with the first-order Taylor expansion.So,the design method of IMC-PID controller was founded.In addition,the analytical expression for robust tuning the adjustable parameter of the IMC-PID controller was derived by the maximum sensitivity specification Ms,and the blindness of conventional method for controller parameter tuning was overcome.The simulation results show that the proposed method can provide a better dynamic performance and robustness against parameters perturbation.