Abstract Since the characteristics of the industrial heat exchange system (HES) are drastically affected by variations of the steam pressure, ambient temperature and water quality, it is difficult for the classical cascade PI control system to meet the desirable control objectives. Therefore, in this paper, a deterministic linear model with unmodeled dynamics is used to describe the dynamic characteristics of the HES. It should be noted that the unmodeled dynamics at the previously sampled instant can be calculated using actual measurements and that the tracking error, which includes effects of the rate of changes of unmodeled dynamics on the controlled model, can be accurately determined. An additional compensating signal is obtained with the feedforward control together with a one-step optimal control law. Consequently, the cascade PI control strategy with the signal compensation is established. The simulation and industrial application show that the proposed method can effectively improve the performance of the cascade PI control system, especially when the unmodeled dynamics is subjected to unknown variations.

中文翻译：

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基于信号补偿的工业换热系统级联PI控制

摘要 由于工业热交换系统（HES）的特性受蒸汽压力、环境温度和水质变化的影响很大，经典的串级PI控制系统难以满足理想的控制目标。因此，在本文中，使用具有未建模动力学的确定性线性模型来描述 HES 的动态特性。应该注意的是，可以使用实际测量来计算先前采样时刻的未建模动态，并且可以准确地确定跟踪误差，包括未建模动态变化率对受控模型的影响。通过前馈控制和一步优化控制法则获得额外的补偿信号。最后，建立了带信号补偿的级联PI控制策略。仿真和工业应用表明，所提出的方法可以有效提高串级PI控制系统的性能，尤其是在未建模动力学受到未知变化的情况下。