基于观测器的非线性时滞系统的自适应模糊控制

Observer-Based Adaptive Fuzzy Control for a Class of Nonlinear Delayed Systems

针对非线性严格反馈时滞系统的自适应模糊控制问题,给出了基于观测器的输出反馈模糊自适应控制方案,利用系统界函数的单调递增性质和模糊逻辑系统的性质,解决非线性严格反馈系统所产生的问题,并设计状态观测器估计系统中不可测的状态变量,用模糊逻辑系统逼近系统中未知的非线性函数,将自适应技术、Backstepping方法与模糊逻辑系统相结合构造自适应模糊控制器,并采用数值例子进行仿真验证。仿真结果表明,系统的所有状态都收敛到原点一个充分小的邻域内,而且在本文所提出的控制率的作用下,闭环系统是稳定的,保证所有信号在闭环系统有界。

This paper considers the problem of observer-based adaptive fuzzy control for a class of nonlinear time-delay systems in strict-feedback form. The monotonicity of system bounding functions and fuzzy logic systems are used overcome the difficulties that arise from strict-feedback systems. A state observer is constructed to estimate the immeasurable state variables. Fuzzy logic systems are used to approximate the un- known nonlinear functions. Adaptive technique and fuzzy logic systems are utilized to construct controller by backstepping approach. The proposed adaptive fuzzy output feedback controller guarantees that all the signals in adaptive closed-loop system are semi-globally uniformly ultimately bounded. And the numerical example is used for simulation experiment. The simulation results show that the proposed control law can guarantee the closed-loop system are stable and the closed-loop system are bounded.