Fractional Transformation-Based Decentralized Robust Control of a Coupled-Tank System for Industrial Applications

Abstract

Petrochemical and dairy industries, waste management, and paper manufacturing fall under the category of process industries where flow and liquid control are essential. Even when liquids are mixed or chemically treated in interconnected tanks, the fluid and flow should constantly be observed and controlled, especially when dealing with nonlinearity and imperfect plant models. In this study, we propose a nonlinear dynamic multiple-input multiple-output (MIMO) plant model. This model is then transformed through linearization, a technique frequently utilized in the analysis and modeling of fractional processes, and decoupling for decentralized fixed-structure H-infinity robust control design. Simulation tests based on MATLAB and SIMULINK are subsequently executed. Numerous assessments are conducted to evaluate tracking performance, external disturbance rejection, and plant parameter fluctuations to gauge the effectiveness of the proposed model. The objective of this work is to provide a framework that anticipates potential outcomes, paving the way for implementing a reliable controller synthesis for MIMO-connected tanks in real-world scenarios.

Optimized design and analysis of cable-based parallel manipulators for enhanced subsea operations

“…Optimizing cable tensions in response to external forces is a crucial area of research (Wahba and Honig, 2023), with recent studies exploring fractional transformation-based control methods to enhance the manipulator responsiveness and robustness (Rahman et al, 2022a,b). The integration of fractional transformation in this area is a promising direction for future research, as it could improve the control and robustness of such systems (Rahman et al, 2023b).…”

Sliding-Mode Control of Horizontal Coupled-Tank Systems using Variable-Speed Pump

“…In [17], a robust nonlinear approach for the control of liquid levels in a quadruple tank system (QTS) is developed based on the design of an integrator backstepping super-twisting controller. Decentralized algorithms were designed to regulate the coupled tank system level [18] and [19]. In [20] and [21], a fractional-order proportional integral (FOPI) control for coupled tank systems was built.…”