In this paper, a modified output–feedback multivariable model reference adaptive control (MRAC) scheme is proposed for a valve-actuated quadruple-tank process with actuator faults. First, a controller parametric model with unknown plant parameters is established, and actuator parameters are determined using a unified actuator fault model. Second, some existing proper modifications that allow MRAC to gain the ability of actuator fault compensation are given. Then final adaptive fault compensation controller is constructed by utilizing existing results and a new adaptation law that is based on a method first used for optimization purposes. The resulting controller allows increasing the learning rate of the adaptation algorithm without causing high-frequency oscillation in control signal and eventually leads to a faster smooth postfault transient response and less reference model tracking error. The stability of the proposed controller is proved such that all closed-loop signals are bounded and tracking error asymptotically converges to zero. Finally, process simulation results are given to exhibit the effectiveness of the proposed scheme.

中文翻译：

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带有执行器故障的四缸过程的改进的自适应容错控制

在本文中，针对具有执行器故障的阀驱动四缸工艺，提出了一种改进的输出-反馈多变量模型参考自适应控制（MRAC）方案。首先，建立具有未知工厂参数的控制器参数模型，并使用统一的执行器故障模型确定执行器参数。其次，给出了一些现有的适当修改，这些修改允许MRAC获得执行器故障补偿的能力。然后，利用现有结果和基于最初用于优化目的的方法的新适应律，构造最终的自适应故障补偿控制器。最终的控制器可以提高自适应算法的学习速度，而不会引起控制信号中的高频振荡，并最终导致更快的平滑故障后瞬态响应和更少的参考模型跟踪误差。证明了所提出控制器的稳定性，从而使所有闭环信号都受到限制，并且跟踪误差渐近收敛于零。最后，给出了过程仿真结果，以证明所提方案的有效性。