未知非线性时滞系统自适应模糊控制

Adaptive fuzzy control for unknown nonlinear time-delay systems

针对一类含有未知函数的非线性时滞系统,提出了一种自适应模糊控制方案.在自适应Backstepping设计方法的基础上,采用模糊逻辑系统辨识非线性未知函数,采用自适应边界技术估计辨识误差上界.通过Domination方法和构造合适的Lyapunov-Krasoviskii泛函相结合,抵消了非线性时滞项对系统的影响.证明了闭环系统为半全局一致本质有界,通过调节设计参数可以实现任意的跟踪精度.实例仿真说明了该方案的可行性.

An adaptive fuzzy control design approach is proposed for a class of nonlinear time-delay systems that include unknown functions. Based on the backstepping design technique, unknown functions are approximated by fuzzy logic systems （FLS）, and the adaptive bounding technique is employed to estimate the upper bound of the approximation errors. The appropriate Lyapunov-Krasovskii functional, combining with the domination technique, is constructed to compensate for the time delays. The closed- loop systems are proven to be semi-globally uniformly ultimately bounded, and the arbitrary output tracking accuracy is guaranteed by tuning the design parameters. Simulation result is presented to show the effectiveness of the approach.