Disturbance Attenuation and Rejection for a Class of Switched Nonlinear Systems Subject to Input and Sensor Saturations

Abstract

This paper investigates the problem of disturbance attenuation and rejection for a class of switched nonlinear systems subject to input and sensor saturations, in which exosystem generated disturbances and H2-norm bounded disturbances are considered. The full-order and reduced-order observers are designed according to whether the system states are available or not. Based on the estimating values of the system states and exosystem generated disturbances, the design schemes for the composite controllers are put forward based on the full-order and reduced-order observers, respectively. For a switched system, the input and sensor saturations would influence the effective synthesis of observer and controller. By sector nonlinearity technology, the stability of the augmented closed-loop systems under the proposed composite controllers are analyzed, and the conditions of synthesis of the observers and controllers are further presented to ensure the augmented systems to be robustly asymptotically stable with a weighted H∞ performance level. An example is given to guarantee the effectiveness of the proposed control schemes.

Robust H∞output feedback control of uncertain fractional-order systems subject to input saturation

“…The PID frequency response is plotted in Figure 2. The PID control system's equation (23) develops to (24)…”

“…In equation (24) as Laplace transform of the PID controller's output, P 2 , P 1 , P 0 2 R n y 3 n u are matrices described by P 2 = K D + tK P , P 1 = K P + tK I and P 0 = K I . We would like to develop the PID controller by using linear system theory in Chen and Shafai 41 and through the state-space realization as long as the ith topic of PFOLM at below…”

“…Of course, the requirements for the configuration of the observers and controllers were addressed to guarantee that the augmented systems were also robustly asymptotically stable with a weighted output level. 24 In a different work, Nguyen and Jabbari 25 investigated output feedback controllers for linear systems with input constraints through the disturbance attenuation approach. The constraints include a restricted actuator size as well as rate limitations.…”

Robust Asynchronous H∞ Observer-Based Control Design for Discrete-Time Switched Singular Systems with Time-Varying Delay and Sensor Saturation: An Average Dwell Time Approach

“…Hence, in the analysis and implantation of the controller, the effect of non-linearity cannot be neglected [33][34][35][36]. Due to its theoretical and practical importance, some representative results regarding sensor saturation for switched systems have been considered [37][38][39]. However, the sensor saturation effect has not been investigated when dealing with the problem of asynchronous ADT observer-based control for discrete-time switched singular systems with time-varying delay.…”