执行器饱和下的最优IMC-PI控制器设计

为了准确评价系统在出现执行器饱和时的跟踪性能,本文研究了饱和条件下基于内模法(Internal Model Control, IMC)的最优PI控制器的设计问题。 当被控对象可近似为一阶带滞后(First Order Plus Dead Time, FOPDT)模型,并选取绝对误差积分(Integral Absolute Error, IAE)为控制器性能指标时, 给出了IAE指标与控制器参数的关系。通过分析闭环传递函数的时域特性,建立控制器输出最大值与控制器参数的解析关系,提出饱和情形下最优IMC-PI控制器的参数的选取方法,并将结果应用于对已有控制器的性能评价。

Optimal IMC-PI Controller Design with Actuator Saturation Constraint

In order to assess the system step tracking performance under actuator saturation accurately, the tuning method of optimal IMC-PI controller has been studied. With the plant approximated by a first order plus time delay (FOPDT) model, and the integral absolute error (IAE) used as the control performance index, the relationship between IAE index and controller tuning parameter is analyzed. By analyzing the closed loop time-response, the analytic relationship between the maximum controller output and the controller tuning parameter has been established. Based on this relationship, the setting of the optimal IMC-PI controller under actuator saturation constraint can be calculated and achieved IAE index can be used to access the controller performance.