This paper deals with the control of a multistage continuous fermenter (MSCF) used for the study of wine fermentation. The control design is facing three main difficulties: 1) system nonlinearity; 2) lack of online measurement of the controlled variable (sugar concentration); and 3) positive constraints on the control inputs (inlet flow rates of each tank) coming from the cascade structure of the system. A control strategy has been proposed, which accounts for these specificities. It is based on an input–output linearization control law coupled with an antiwindup technique and a state observer (the Kalman filter). The strategy has been tested and validated first on numerical simulations and then applied to the real process. The experiments gave satisfactory results that open up new perspectives on the use of the MSCF.

中文翻译：

---

具有输入约束的多级连续发酵罐控制的抗饱和输入-输出线性化策略

本文涉及用于葡萄酒发酵研究的多级连续发酵罐（MSCF）的控制。控制设计面临三个主要困难：1）系统非线性；2）缺乏在线测量控制变量（糖浓度）的方法；3）来自系统级联结构的控制输入（每个水箱的入口流量）受到正约束。已经提出了控制策略，其考虑了这些特异性。它基于输入输出线性化控制定律，结合了抗饱和技术和状态观察器（卡尔曼滤波器）。该策略已首先通过数值模拟进行了测试和验证，然后应用于实际过程。实验给出了令人满意的结果，为MSCF的使用开辟了新的前景。