一种多变量预测控制的分程控制策略实现方法

An implementation of split control strategy for multi-variable predictive control

针对包含分程控制回路的控制系统具有非线性特征,提出一种适用于多变量模型预测控制的分程控制实现方法.在分程控制的各线性区间内根据各分程阀的不同动作组合建立预测模型,通过在线比较控制器输出信号值与相应定义的中间阈值选择模型,模型发生切换时保留切换前模型中的输出预测值作为当前模型下的初始输出预测值;解决了控制过程存在分程控制需求时,多变量预测控制器的设计问题,提高了线性预测控制器的适用范围.仿真结果验证了所提出方法的有效性.

The control system with the split control loop always has nonlinear characteristics,therefore,a method of split control implementation is proposed for multi-variable model predictive control.In each linear interval of the split control loop,the predictive models are established respectively according to different combination of the split valves.The control models are chosen by comparing the controller signal output values with the predefined middle threshold.After the control models being switched,the predicted output values of the old control model are regarded as the original output predicted values of the proposed model.The design problems of the multi-variable model predictive controller are solved when the process is needed to be split-range control,which enhances the applicability of the linear MPC.Finally,the simulation examples are given to verify the effectiveness of the proposed method.