Sliding Mode Control Of Singularly Perturbed Systems Based On T-S Fuzzy Model

Advanced control of nonlinear uncertain systems is one of the hot topics in modern control theory,and has attracted widespread attention from many experts and scholars.However,the existing methods are difficult to be applied to dynamic systems with comprehensive and complex characteristics such as in engineering fields such as aerospace,chemical process,and power electronics which with nonlinearities,uncertainties,multi-source disturbances and multi-time scales.In view of this,this thesis combines T-S fuzzy model,sliding mode control and singular perturbation theory to study the sliding mode control method of singularly perturbed systems based on T-S fuzzy model,which aims to solve the system control problems of nonlinearities,uncertainties,multi-source disturbances and multi-time scales characteristics.The main results are summarized as follows:1.A fuzzy sliding mode stabilization control method for singularly perturbed systems based on disturbance observer(DOB)is proposed.First,a DOB is designed to estimate the disturbances according to the structural characteristics of the T-S fuzzy systems.Next,an observer-based sliding mode stabilization controller is designed and the controller satisfy the reaching condition is proved.Then,the parameters of the sliding mode controller are determined by solving the linear matrix inequalities(LMIs),and the stability of the closed-loop system is proved by using the Lyapunov stability theory.Finally,simulation results are used to demonstrated the effectiveness and superiority of the control method.2.A model reference fuzzy sliding mode tracking control method for singularly perturbed systems is proposed.First,for the singularly perturbed systems based on the T-S fuzzy model,combined with reference signal model,the augmented singularly perturbed systems are obtained.Secondly,the overall integral sliding mode surface is designed.The tracking controller gain matrix is designed by using LMIs method and the stability of closed-loop system is proved.Finally,the effectiveness of the method is demonstrated by using non-linear circuit simulation experiment.3.A fuzzy sliding mode tracking control method with discount factor for singularly perturbed systems is proposed.First,for the singularly perturbed systems based on the T-S fuzzy model,the augmented singularly perturbed systems are constructed by combining reference signal model.Then,the H? performance index with a discount factor is proposed to deal with the bounded reference tracking signal,the gain matrix of the sliding mode tracking controller is determined by solving the LMIs,and the states of the closed-loop system are bounded.Finally,the simulation experiment on the motor system are used to illustrate the practicability and effectiveness of the method.