الفهرس 
An Overview of Binary Distillation ColumnsOnly 14 pages are availabe for public view
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Abstract
This thesis presents a comparative study of different decoupling control schemes for a class of MIMO chemical processes via PI controller. The design of Smith predictor to compensate the time delay problem also presented. Chemical processes consist of several measurement and control signals, and there are often complicated couplings with time delay between them, which can cause difficulties in feedback controller design. The main advantage of the Smith predictor is that the time delay is eliminated from the characteristic equation of the closed loop system. Decoupling control has emerged as one of the most popular techniques in chemical industrial process. The basic idea of decoupling control is to weaken, or even eliminate, the interactions between different input and output signals by decoupling methods. Then, the advanced control methods could be applied to the separated SISO subsystems. The key idea of this thesis is designing a fuzzy decoupling schemes depending on human knowledge, instead of conventional decoupling schemes that depend on system mathematical model. Based on conventional decoupling, fuzzy decoupling scheme is developed, also based on inverted decoupling, inverted fuzzy decoupling scheme is developed. The control effect is compared using simulation results for the proposed two schemes with conventional decoupling and inverted decoupling. The proposed schemes are easy to realize and simple to design, besides they have a good decoupling capability. The determination of the main PI controller parameters for each controlled loop is simplified and facilitated. The problem of stability is formulated including the proposed decoupling schemes. The Wood and Berry model of a binary distillation column is used to illustrate the applicability of the proposed schemes.