Selection of Decoupling Control Methods Suited for Automated Design for Uncertain TITO Processes

This paper evaluates different decoupling control methods for uncertain TITO processes with respect to automated design: Static and Dynamic Simplified Decoupling Control, Centralized Inverted Decoupling Control and Centralized PID Control by Decoupling. Each decoupling control method requires different approximation steps. High approximation accuracies are crucial for the control performance but cannot be achieved for every combination of decoupling control method and system specific characteristics. Thus, the goal of this paper is to support the selection of the most appropriate decoupling control method. For this purpose new quantitative criteria are developed. They allow selecting the method directly based on the most relevant system characteristics. A good selection allows an automated and repeatable design procedure and good control performances for uncertain, time variant and nonlinear systems. The applicability and the best selection of the decoupling control method is illustrated for three examples and results are compared to decentralized PI control. For practical reasons, all evaluations are restricted to Two-input Two-output systems whose transfer functions can be approximated with First-order time delay elements.