L∞-gain adaptive fuzzy fault accommodation control design for nonlinear time-delay systems
Huai-Ning Wu1, Xiao-Hong Qiang, Lei Guo
1School of Automation Science and Electrical Engineering, Beihang University, Beijing, China. whn@buaa.edu.cn
Summary
This study introduces adaptive fuzzy fault accommodation (FA) control for nonlinear time-delay systems. The developed controllers ensure system stability and performance despite faults and disturbances.
Area of Science:
- Control Engineering
- Nonlinear Systems
- Fuzzy Logic
Background:
- Nonlinear time-delay systems are susceptible to faults and disturbances, impacting performance.
- Existing fault accommodation (FA) methods may struggle with unknown fault functions and system nonlinearities.
Purpose of the Study:
- To develop an adaptive fuzzy fault accommodation (FA) control design for nonlinear time-delay systems.
- To guarantee L(∞)-gain performance under persistent bounded disturbances and unknown faults.
Main Methods:
- Utilized Lyapunov techniques and Razumikhin-type lemma for stability analysis.
- Employed fuzzy logic systems to approximate unknown fault functions.
- Formulated controller existence conditions using linear matrix inequalities (LMIs).
Main Results:
- Developed adaptive fuzzy FA controllers with guaranteed L(∞)-gain performance.
- Ensured uniform ultimate boundedness of closed-loop system responses in the presence of faults.
- Obtained suboptimal controllers by minimizing L(∞)-gain upper bounds via LMI optimization.
Conclusions:
- The proposed adaptive fuzzy FA control scheme effectively handles nonlinear time-delay systems with faults and disturbances.
- Simulation results on a continuous stirred tank reactor (CSTR) validate the controller's effectiveness.
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