Universal adaptive control for a class of nonlinear time-varying delay systems with unknown output function.
1Key Laboratory of Measurement and Control of CSE, Ministry of Education, School of Automation, Southeast University, Nanjing, Jiangsu 210096, China.
ISA Transactions
|March 1, 2021
Summary
This study addresses stabilization for nonlinear time-varying delay systems with unknown parameters. An adaptive observer and controller are developed for global system stabilization, verified by examples.
Area of Science:
- Control Systems Engineering
- Nonlinear Dynamics
- Adaptive Control Theory
Background:
- Nonlinear time-varying delay systems present significant control challenges due to uncertainties.
- Stabilization is crucial for the reliable operation of these complex systems.
Purpose of the Study:
- To develop a robust control strategy for nonlinear time-varying delay systems with unknown growth rates and output functions.
- To design an adaptive observer and controller for global stabilization.
Main Methods:
- Introduction of dynamic gain for adaptive observer design.
- Utilization of Lyapunov-Krasovskii functional for adaptive controller synthesis.
- Analysis of closed-loop system stability.
Main Results:
- An adaptive observer is successfully designed to estimate system states.
- A globally stabilizing adaptive controller is proposed.
- The controller's effectiveness is demonstrated through two illustrative examples.
Conclusions:
- The proposed adaptive observer and controller effectively achieve global stabilization for the considered class of systems.
- The dynamic gain approach offers a viable solution for handling unknown parameters in nonlinear delay systems.
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