Robust Adaptive Switching Fault-Tolerant Control of a Class of Uncertain Systems against Actuator Faults

Xiao-Zheng Jin

doi:10.1155/2013/852502

Abstract

This paper deals with the fault-tolerant control (FTC) problem for a class of linear time-invariant systems with time-varying actuator faults and uncertainties. For more general consideration, the faults and uncertainties are supposed to depend on the states of systems and unknown constant bounds. For the sake of eliminating the effects of such state-dependent faults and uncertainties automatically, a switching control strategy which is formulated by a sign function is designed to configure controller based on system’s states. And some adjustable control parameters are updated via designing adaptive laws. Based on the information from switching function and the adaptive estimation mechanism, the robust adaptive controllers are constructed to compensate for the effects of faults and uncertainties. Through Lyapunov functions and adaptive schemes, the asymptotic stability of the resulting adaptive FTC uncertain system can be achieved. The effectiveness of the proposed design is illustrated via a rocket fairing structural-acoustic model.

Highlights

In recent years, the safety, reliability, and validity of practical systems have attracted growing attention
In the event of an actuator fault, the traditional feedback control design may result in unsatisfactory performance of systems or even cause other catastrophic consequence
The active fault-tolerant control (FTC) methods based on fault detection and isolation (FDI) technique can reconfigure or reconstruct controllers by using the real-time fault information provided by the fault diagnosis mechanism [16,17,18]

Summary

Introduction

The safety, reliability, and validity of practical systems have attracted growing attention. Motivated by the effectiveness and real-timely of eliminating a variety of actuator faults, we design a novel active FTC methodology based on adaptive technique to automatically accommodate faults in this paper. The papers [8, 9] utilized Hamilton-Jacobi-inequality-based approach and adaptive diagnostic-based approach to solve the FTC problem, respectively In those studies, the uncertainties were always considered as norm bounded, sector-bounded, and polytopic-type uncertainties. A novel switching adaptive method is proposed to solve the robust fault-tolerant control compensation problem of a class of uncertain linear systems. Similar to the adaptive controllers designed in [25, 26], the proposed adaptive approach can be used for the general actuator fault model, which covers the cases of normal operation, loss of effectiveness, outage, and unparameterizable bias/stuck faults.

Preliminaries and Problem Statement

Switching Robust Adaptive FTC System Design

Numerical Example

Conclusion