基于高增益观测器的SISO非线性系统模糊自适应输出反馈控制

Adaptive Fuzzy Backstepping Output-feedback Control for SISO Nonlinear Systems Based On High-gain Observer

针对一类状态不可测的SISO非线性不确定系统,提出一种新的模糊自适应Backstepping输出反馈控制,利用模糊逻辑系统逼近未知非线性函数,设计模糊自适应高增益观测器对系统未知状态进行观测,利用模糊自适应Backstepping控制方法设计模糊自适应输出反馈控制器。通过理论分析证明了闭环系统是半全局一致最终有界的;观测误差和跟踪误差都分别收敛到零的一个小邻域内。

An adaptive fuzzy backstepping output-feedback control approach was proposed for a class of SISO nonlinear systems with completely unknown functions and without the measurements of states. Fuzzy logic systems were employed to approximate the unknown nonlinear functions, and an adaptive high-gain observer was developed to estimate the unmeasured states. Using the designed high-gain observer, and combining the fuzzy adaptive control theory with backstepping approach, a novel adaptive fuzzy backstepping output-feedback control scheme was designed. It is proved that the proposed control approach can guarantee all the signals of the closed-loop system which are semi-globally, uniformly and ultimately bounded （SUUB）, the observer errors and the tracking errors converge to a small neighborhood of the origin by appropriate choice of the design parameters. Finally, a simulation example is provided to show the effectiveness of the proposed approach.