Robust IMC PID Controller Desig uin VRFT: Theoretical and

The controller design in the data-driven Virtual Reference Feedback Tuning (VRFT) method mainly depends on the selection of the closed-loop (M(z)) reference model, so the choice of M(z) is always an open problem. In addition, controllers designed for industrial applications must balance performance and robustness. In the literature, the choice of M(z) means a selection of parameters (order and delay) that are chosen at random and based on closed-loop performance but not on robustness. We propose a new robust PID controller design using VRFT based on the IMC scheme to improve the performance and robustness. The benefits of an integrated IMC scheme with VRFT are flexibility in tuning, improved robustness, and reduced control effort. The proposed approach identifies optimal parameters of M(z) and 2(nd) order IMC filter (G(f)(z)) according to the specific Maximum Sensitivity (M-s) with the minimum VRFT objective function (J(VR)). The effectiveness of the proposed approach is confirmed by numerical examples and validated experimentally through the temperature control process. Furthermore, the fragility and robustness analysis are probed with perturbations in the controller and plant parameters. Simulation and experimental results show that the proposed method provides improved performance and robustness. Copyright (c) 2022 The Authors. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/) .