輔以觀測器針對未知非線性系統使用不確定性邊界估測的適應模糊控制器設計

OBSERVER-BASED ADAPTIVE FUZZY CONTROLLER DESIGN FOR UNKNOWN NONLINEAR SYSTEM USING ESTIMATION OF BOUNDS FOR UNCERTAINTY

汪睿榮(Ruei-Rung Wang)

指導教授 ： 呂虹慶

大同大學/電機資訊學院/電機工程學系所/碩士(2005年)

摘要

本論文針對不確定的單輸入單輸出未知非線性系統，提出一個以觀測器為基礎的適應模糊控制方法。這些未知非線性項可由一模糊邏輯系統近似，且模糊邏輯系統中的參數可透過適應法則做即時調整，並達到控制非線性系統之輸出去追蹤預設之運行軌跡。所提方法不需要假設狀態變數完全可觀察，而且不需預先知道包含此近似誤差和外部干擾之不確定項的上界。其中狀態變數由設計的觀測器所估測。應用李亞普諾夫 (Lyapunov) 穩定定理，以保證閉迴路系統中的狀態估測誤差和追蹤誤差以及其它信號皆為均勻最終有界(uniformly ultimately bounded)。最後，將所提出的方法應用於一些非線性系統，模擬的結果可以證明提出控制方法的有效性。

關鍵字

模糊邏輯系統 ； 李亞普諾夫穩定定理 ； 均勻最終有界

並列摘要

In this thesis, an observer-based adaptive fuzzy control method for uncertain single-input single-output nonlinear dynamical systems with unknown nonlinearities is proposed. The unknown nonlinearities are approximated by the fuzzy logic system whose parameters can be adjusted on-line according to some adaptive laws for the purpose of controlling the output of the nonlinear system to track a given trajectory. The proposed method need not the assumption that the state variables full observability, and does also not require any priori knowledge of the upper bounds on the uncertainties including approximations errors and external disturbances. And the state variables can be estimated by designing the observer. The Lyapunov stability theory is used to guarantee a uniformly ultimately bounded for the state estimation error and tracking error as well as all other signals in the closed-loop system. Finally, the proposed method is applied to control some examples of nonlinear systems and simulation results demonstrate the effectiveness of the control scheme.

並列關鍵字

fuzzy logic system ； Lyapunov stability theory ； uniformly ultimately bounded

參考文獻

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