Abstract This paper presents a controller design method for the open-loop unstable process in the primary loop and the open-loop unstable, integrating and stable processes in the secondary loop of the simple cascade control configuration. The controller of the secondary loop and the primary loop is designed through a direct synthesis (DS) approach in the frequency domain for load disturbance rejection and set-point tracking, respectively. Moreover, a set-point filter is used to reduce unnecessary overshoot in servo tracking. The proposed method is applicable to a wide range of processes having unstable, integrating and stable dynamics in a unified way. It avoids the complexity of order reduction and dead time approximation of the plant. The simulation study illustrates that the present approach provides enhanced closed-loop performance as compared to the approaches recently reported in the literature.

中文翻译：

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使用直接综合方法增强对不稳定级联系统的控制

摘要 本文提出了一种简单级联控制配置的初级回路开环不稳定过程和次级回路开环不稳定、积分和稳定过程的控制器设计方法。次级回路和初级回路的控制器是通过频域中的直接合成 (DS) 方法设计的，分别用于负载干扰抑制和设定点跟踪。此外，设置点滤波器用于减少伺服跟踪中不必要的过冲。所提出的方法以统一的方式适用于具有不稳定、积分和稳定动力学的广泛过程。它避免了设备降阶和死区时间逼近的复杂性。