Fault-Tolerant Control Based on Virtual Actuator and Sensor for Discrete-Time Descriptor Systems

Abstract

This article proposes a fault-tolerant control (FTC) strategy based on virtual actuator and sensor for discrete-time descriptor systems subject to actuator and sensor faults. The fault-tolerant closed-loop system, which includes the nominal controller and observer, as well as the virtual actuator and the virtual sensor, hides the effects of faults. When an observer-based state-feedback law is considered, the existence of algebraic loop may prevent the practical implementation due to the current algebraic states depending on the current control input, that affects also the implementation of the virtual actuator/sensor. To deal with this issue, an observer-based delayed feedback controller and a delayed virtual actuator are proposed for discrete-time descriptor systems. Furthermore, the satisfaction of the separation principle is shown, and an improved admissibility condition is developed for the design of the controller and virtual actuator/sensor. Finally, some simulation results including an electrical circuit are used to demonstrate the applicability of the proposed methods.

Virtual Sensors Design for Nonlinear Dynamic Systems

“…Consider Lyapunov candidate function 𝑉(𝑡) = 𝑒 𝑇 (𝑡)𝑃𝑒(𝑡) and take its derivative using ( 23) and ( 24) so obtain a new form (25). Clearly, if as in (26).…”

“…𝑉 ̇(𝑡) = (𝐹 * 𝑒(𝑡) − 𝛥𝜙(𝑡)) 𝑇 𝑃𝑒(𝑡) + 𝑒 𝑇 (𝑡)𝑃(𝐹 * 𝑒(𝑡) − 𝛥𝜙(𝑡)) = 𝑒 𝑇 (𝑡)(𝐹 * 𝑇 𝑃 + 𝑃𝐹 * )𝑒(𝑡) + 2𝑒 𝑇 (𝑡)𝑃𝛥𝜙(𝑡) = −𝑒 𝑇 (𝑡)𝑊𝑒(𝑡) + 2𝑒 𝑇 (𝑡)𝑃𝛥𝜙(𝑡) ≤ −||𝑒(𝑡)|| 2 (𝜆 * 𝑚𝑎𝑥 𝑚𝑖𝑛(25) …”

A predictive fault tolerant control method for qLPV systems subject to input faults and constraints

“…Real instrumented control systems are naturally subject to possible faults, failures and component malfunctions [1]. Accordingly, over the last couple of years, a considerable amount of attention has been given to the synthesis of Fault Tolerant Control (FTC) schemes [2,3,4]. These algorithms are able to offer increased process availability by avoiding breakdowns and maintaining performances despite faults.…”

Virtual Sensor Design for Linear and Nonlinear Dynamic Systems

“…A new architectural paradigm for remotely deployed sensors whereby a sensor's software is separated from the hardware are presented in [18]. In [2,13], different theoretical aspects of using virtual sensors in linear systems are considers; in [19], virtual sensors are used for fault tolerant control in linear descriptor systems. Detailed procedure to design virtual sensors of full dimension for linear systems is suggested in [4].…”