Tracking control and disturbance rejection for nonlinear switched control systems with saturation effects

Abstract

This article focuses on the concerns of a tracking control and active disturbance rejection for nonlinear switched systems described by Takagi–Sugeno fuzzy framework with state‐dependent nonlinear perturbations, actuator saturations and disturbances. Especially, a nonlinear equivalent‐input‐disturbance technique is employed to guarantee that only the external disturbances are rejected while retaining the beneficial nonlinearity of the system. Notably, with the aid of the lifting technique, the modified repetitive control are accurately described by a continuous‐discrete two‐dimensional model is designed to improve the tracking precision. The fuzzy‐membership‐function‐dependent piecewise Lyapunov–Krasovskii functional (LKF) by exploiting the knowledge of the membership functions are built to assure the exponential stability of the investigated system. Moreover, the controller and observer gains can be obtained as solutions to a set of strict linear matrix inequalities. Finally, an application example based on the cognitive radio model is given to verify the efficacy of the proposed control protocol.

Robust compensation for active disturbance rejection control of a class of high‐order systems with large time delay: Simulation and experimental studies

“…The extended state observer (ESO), which is used in ADRC, estimates all uncertainties as “unknown disturbances,” which are then corrected in the loop. The development of linear ADRC 13 substantially aided the industrial use of ADRC 14‐17 . ADRC has been used for a long time to study the control of large inertial systems, 18 such as chemical production process, 19 fully distributed automatic generation control, 20 distributed parameter system, 21‐24 main steam temperature control 25 .…”

“…The development of linear ADRC 13 substantially aided the industrial use of ADRC. [14][15][16][17] ADRC has been used for a long time to study the control of large inertial systems, 18 such as chemical production process, 19 fully distributed automatic generation control, 20 distributed parameter system, [21][22][23][24] main steam temperature control. 25 In their work, 26 the authors achieved almost feedback-linearization by employing a low-power extended observer.…”