具有未知截止區之不確定非線性時間延遲系統之強健適應模糊控制器設計

DESIGN OF ROBUST ADAPTIVE FUZZY CONTROLLER FOR UNCERTAIN NONLINEAR TIME-DELAY PLANTS WITH UNKNOWN DEAD-ZONE

張凱翔(Kai-Hsiang Chang)

指導教授 ： 江江盛

大同大學/電機資訊學院/電機工程學系所/碩士(2008年)

摘要

本論文針對某一類具有未知截止區的不確定非線性時間延遲系統提出一個強健適應模糊控制器設計。截止區及時間延遲特性在許多工程系統上是眾所皆知的，例如：伺服控制系統、微定位系統等。 對於上述這些系統，存在於致動器內部的截止區特性限制了系統的性能。一般而言，截止區特性是知之甚微並且隨時間變化。另外，時間延遲特性通常是系統不穩定的根源。因此，具有時間延遲特性系統之穩定度分析的癥結已經成為控制設計工程師最重要的課題。其次，利用具有適應法則之模糊邏輯系統方法去近似一個未知非線性函數的受控系統，基於李亞普諾夫穩定定理，所提出強健適應模糊模式控制方法能夠確保致動器在具有未知截止區之整個閉迴路非線性時間延遲系統中可以獲得良好追蹤成果。最後，對於所提出之控制器設計方法，本論文將以例題和電腦模擬結果來說明並驗證其有效性。

關鍵字

非線性系統 ； 模糊控制 ； 適應控制 ； 強健控制 ； 截止區 ； 時間延遲

並列摘要

A robust adaptive fuzzy control framework is proposed in this thesis for a class of uncertain nonlinear time-delay systems containing an unknown dead-zone. It is well known that dead-zone characteristics and time-delay are frequently encountered in various engineering systems such as servo control system and micro positioning systems. For many of these systems, the performance is limited by dead-zone in the actuator. Generally, the dead-zone characteristics are usually poorly known and time-variant. Moreover, the existence of time-delay is frequently a source of instability in the real systems. Hence, the problem of stability analysis of time delay nonlinear systems with a dead zone has been one of the most important topic for the control design engineer. According to some adaptive laws, the unknown nonlinear functions of the plant are approximated by the fuzzy logic system. Based on Lyapunov stability theorem, the presented robust adaptive fuzzy control framework can not only guarantee the robust stability of the overall closed-loop nonlinear time-delay system containing an unknown dead-zone in the actuator but also obtain good tracking performance as well. Eventually, some illustrative examples are given to verify the validity of the developed controller.

並列關鍵字

Nonlinear System ； Fuzzy Control ； Adaptive Control ； Robust Control ； Dead-Zone ； Time-Delay

參考文獻

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