Physics Procedia 33 ( 2012 ) 1753 – 1761
1875-3892 © 2012 Published by Elsevier B.V. Selection and/or peer review under responsibility of ICMPBE International Committee.
doi: 10.1016/j.phpro.2012.05.281
2012 International Conference on Medical Physics and Biomedical Engineering
Adaptive Variable Structure Control for Linear Systems with
Time-varying Multi-delays and Mismatching Uncertainties
*
MENG Bo
1
,GAO Cunchen
2
TANG Shuhong
3
,LIU yunlong
3
1
School of Information Science and Engineering
2
School of Mathematics Sciences Ocean University of China Qingdao, 266100, China
3
School of Information Science and Engineering Ocean University of China Qingdao, 266100, China
oucmengbo@gmail.com
1
, ccgao@ouc.edu.cn
2
, {wfxytang, fhylren}@163.com
3
Abstract.
This paper discusses the control problems of linear systems with time-varying multi-delays and mismatching
uncertainties. A new adaptive variable structure control strategy is given by Lyapunov stability theory. The full
invariance of sliding mode with time-varying multi-delays and mismatching uncertainties is proved in the
circumstances sliding surface coefficient matrix C to satisfy certain matching conditions. The control strategy ensures
that the closed-loop system is globally stable. Simulation results further show that the strategy is feasible and
effective.
© 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of [name organizer]
Keywords: Time-varying multi-delays, Linear systems, Adaptive variable structure control, Mismatching uncertainties.
1. Introduction
Time-delay commonly exists in various engineering systems, for example, the turbojet engine, aircraft
systems, microwave oscillator, nuclear reactor, rolling mill, chemical process, manual control, and long
transmission line in pneumatic, hydraulic systems [1-3, 4, 6]. The existence of time delay in a system
frequently becomes a source of instability. Since the time-varying uncertainties (structured or unstructured)
are inevitable in many practical linear systems, the control of the linear systems with time-varying
uncertainties has been an important research topic in the engineering area. The variable structure control
*
This work was supported by the National Natural Science Foundation of China (No.60974025).
Available online at www.sciencedirect.com
© 2012 Published by Elsevier B.V. Selection and/or peer review under responsibility of ICMPBE International Committee.