Robust model-predictive-control for a constrained nonlinear system with bounded disturbance

DOI编号  10.7641/j.issn.1000-8152.2011.5.CCTA091554
2011,28(5):709-714

 作者 单位 E-mail 秦伟伟 国防科技大学 机电工程与自动化学院 第二炮兵工程学院 自动控制工程系 qww_1982@163.com 马建军 国防科技大学 机电工程与自动化学院 刘刚 第二炮兵工程学院 自动控制工程系 郑志强 国防科技大学 机电工程与自动化学院

针对一类干扰有界约束非线性系统设计了基于控制不变集切换策略的鲁棒模型预测控制算法. 针对非线性系统线性化之后的结果, 给出了平衡点的非线性标称系统控制不变集的计算方法. 然后在考虑线性化误差和加性有界干扰影响的基础上, 构造了平衡点附近最小鲁棒正不变集. 结合不变集切换策略和Tube不变集控制方法, 提出了干扰有界约束非线性系统的不变集切换策略. 最后将该算法应用到一类典型的非线性化工过程连续搅拌反应釜(CSTR)中, 仿真结果验证了算法的有效性.

For a constrained nonlinear system with bounded disturbance, we develop a new robust model predictive controller(MPC) based on the switching strategy of control-invariant set. Firstly, we propose for the nominal nonlinear system an algorithm for calculating the control-invariant set through linearizing the nonlinear system around the equilibrium point. Secondly, considering the effect of linearization errors and additive bounded disturbances, we determine the minimal robust positively invariant set around the equilibrium point. The robust MPC algorithm is then developed for the constrained nonlinear system with bounded disturbances, based on the switching strategy of the control-invariant set and the control strategy of the Tube-invariant set. The method is tested in a typical nonlinear continuously stirring tank reactor(CSTR); the results show the feasibility of the proposed method.