Analysis And Control Of A Class Of Switched T-S Fuzzy Systems

In the past 20 years, fuzzy control technique has developped quickly and was applied to many fields successfully. Currently, fuzzy control combined with other technologies becomes a hot point. In this thesis, switched system theory is introduced to T-S fuzzy systems and stability issue is addressed. The main contributions are as follows:Hybrid control is studied for T-S fuzzy systems. These T-S fuzzy systems are controlled by multiple controllers, and any single controller can not stabilize the system. Multiple Lyapunov functions method is introduced to design the switching law between controllers, the system is asymptotically stable under the switching law. At the same time, sufficient conditions are derived for stabilization and are formulated in the format of LMIs. On this basis, the same method is adopted for hybrid control stabilization problem is solved for fuzzy time-delay systems with uncertainty, and get corresponding conclusion.Stability under arbitrary switching is studied for a class of switched T-S fuzzy systems including stability of switched T-S fuzzy time-delay system without control, stability of switched T-S fuzzy time-delay system under PDC controllers and stability of switched T-S fuzzy system with time-delay in input and state. Common Lyapunov functions are applied to derive the conditions for stabilization under arbitrary switching.