约束Hammerstein系统构造性预测控制及其在聚丙烯牌号切换控制中的应用

针对具有状态、输入和中间变量约束的连续时间Hammerstein系统，提出了一种多变量构造性模型预测控制策略。首先，基于Hammerstein系统的特殊结构，利用Raccati方程构造线性环节的控制Lyapunov函数，进而设计其一族可调控制律（即稳定控制类）。其次，对约束Hammerstein系统定义一个有限时域滚动优化控制问题，通过在线优化计算实际预测控制量。利用Lyapunov稳定性定理建立闭环系统渐近稳定的充分条件。最后，以工业聚丙烯装置牌号切换控制为例，仿真验证本文结果的有效性。

Constructive predictive control of constrained Hammerstein systems and its application to grade transition control of polypropylene

One multi-variables constructive model predictive control strategy is developed for continuous-time Hammerstein systems with constraints on the state,input and intermediate variable.Firstly,based on the special structure of Hammerstein systems,one control Lyapunov function is constructed for the linear subpart via the Raccati equation.This leads to a class of adjustable control law(i.e.stable control class)of the linear subpart.Secondly,a finite receding horizon optimal control problem is defined for the constrained Hammerstein system,which is computed on-line to derive the actual predictive control actions.The sufficient condition for asymptotically stability of the closed-loop system is obtained by the Lyapunov’s theorem.Finally,the simulation example of the grade transition control of industrial polypropylene plants is used to illustrate the effectiveness of the results obtained here.