Design and parameter tuning of active disturbance rejection control for uncertain multivariable systems via quantitative feedback theory☆

This paper proposes a new parameter tuning approach for active disturbance rejection control (ADRC) of multi-input multi-output (MIMO) uncertain systems. Firstly, decentralized ADRC (DADRC), dynamic decoupling ADRC (DD-ADRC), and inverted decoupling ADRC (ID-ADRC) are introduced. Three control schemes are uniformly transformed into a two-degree-of-freedom (2DOF) equivalent structure for analysis. Then, a parameter tuning approach based on multivariable quantitative feedback theory (QFT) is proposed to achieve the desired performance. Considering the coupling effects, the QFT performance specifications are reformulated to reduce the conservatism in design, and the closed-loop stability conditions are studied to establish the robust stability performance specification. Finally, the control schemes and the proposed tuning approach are applied to a heat integrated distillation column (HIDiC) process. The effectiveness of the parameter tuning approach is verified, and the respective advantages of the ADRC control schemes are analyzed in parameter tuning and simulations. (c) 2023 ISA. Published by Elsevier Ltd. All rights reserved.