Fuzzy Adaptive Control Design And Its Application In Mechanical And Electrical Systems

Under the framework of fuzzy adaptive backstepping control theory and robust control theory,in order to achieve the high performance control system,this thesis proposes the adaptive fuzzy control design scheme for mechanical and electrical systems.The main research work of this thesis is as follows:(1)For a simplifying single-link robotic manipulator coupled to a brushed direct current(DC)motor system with actuator saturation and unmeasured states,an adaptive fuzzy output feedback control method is proposed.The fuzzy logic systems are used to modeling for the simplified model.To address output constraint and input constraint,a barrier Lyapunov function and an auxiliary design system are employed,respectively.Fuzzy logic systems are used to approximate the unknown nonlinear functions.Stability proof of the overall closed-loop system is given via the Lyapunov method.The control method can guarantee that all the signals in the closed-loop system are bounded and the system output can follow the given bounded reference signal.(2)For a single-link robotic manipulator coupled to a brushed direct current(DC)motor system with actuator saturation,an tracking control design method is designed.Fuzzy logic systems are used to model the controlled object.The filtered signals are introduced to eliminate the interference of high frequency signals.The virtual/actual control inputs are derived from the solutions of a series of dynamical equations.Under the framework of the backstepping control design,an observer-based output feedback control design scheme is proposed.It is proved that the control approach can guarantee that all the signals in the closed-loop system are bounded.(3)By combining the command-filter technique with the backstepping design algorithm,for a single-link robotic manipulator system with the unknown nonlinear function and the actuator saturation,a new adaptive fuzzy tracking backstepping control method is developed.In the control design,fuzzy logic systems are used to model the controlled object,and a smooth function is used to approximate the actuator saturation,then It is proved that adaptive fuzzy control scheme can guarantee that all the variables in the closed-loop system are bounded,and also that the system output can track a given reference signal as closely as possible.The simulation is provided to illustrate the effectiveness of the proposed approach.(4)For a permanent magnet synchronous motors(PMSM)system,an adaptive fuzzy output feedback tracking control design method is studied.Fuzzy logic systems are used to model the controlled object.For the cases of the immeasurable states and senseless,a state observer is proposed to solve the immeasurable states problem.In the unified framework of adaptive backstepping control design and utilizing the Barrier Lyapunov Function method,the output constraint problem is studied.The simulation results are given to illustrate the effectiveness of the proposed control method for the PMSM.(5)For a induction motor system with dead-zone compensation,an adaptive fuzzy output feedback control method is designed.Fuzzy logic systems are used to model the controlled object,fuzzy state observer is designed for the unknown parameters,the Nussbaum function are used to solve the unknown control direction problem,under the framework of the adaptive fuzzy backstepping control design,the controller are proposed,the controller and parameter adaptive laws can not only overcome the change of motor system parameters and load disturbance but also ensure the stability of the closed-loop system.Simulation results are presented to illustrate the effectiveness of the proposed control method.