本文给出一种双层结构预测控制的整体解决方案.该方案分为开环预测、稳态目标计算和动态控制三个模块.开环预测基于实测被控变量值和过去的操作变量值,在假设未来操作变量不再变化的情况下,估计未来的被控变量值.稳态目标计算根据开环预测结果和外部目标等要求,计算操作变量、被控变量的稳态目标值以及软约束的放松量.动态控制根据开环预测结果和稳态目标输出结果,计算未来的控制作用增量序列,采用经典的动态矩阵控制策略.这个整体解决方案保证了三个模块在模型、约束、目标上的一致性.该算法是在已有文献的基础上,将三个模块统一处理得到的.仿真与应用例子证实了该算法的有效性.
This paper gives an overall solution to the double-layered model predictive control(MPC). This scheme includes three modules, i. e., the open-loop prediction, the steady-state target calculation(SSTC), and the dynamic control. Based on real-time output measurement and past inputs, the open-loop prediction module estimates the future outputs by assuming that the future inputs keep unchanged. Based on the open-loop predictions and the external targets,the SSTC module calculates the steady-state targets and the slacking values of the soft constraints. Then according to the open-loop predictions and SSTC results, the dynamic control module calculates the future control increments, which applies the classical dynamic matrix control(DMC). This overall solution guarantees the consistency of the three modules with respect to model, constraints and targets. Simulation and application examples have verified the effectiveness of the proposed algorithm.