針對不確定非線性離散時間系統之強健適應模糊控制器設計

ROBUST ADAPTIVE FUZZY CONTROLLER DESIGN FOR UNCERTAIN NONLINEAR DISCRETE-TIME SYSTEMS

張志榮(Chih-Jung 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(2006年)

摘要

一般來說，強健的特性以及不確定系統的穩定性大部分被注意在連續時間的系統。本論文針對具有一些不確定非線性離散時間系統，提出一個離散時間的強健適應模糊控制方法。藉由適應模糊的方法去近似受控系統中未知的非線性函數，除此之外，本文還利用在一個扇形區域中的可變結構控制去補償近似誤差。李亞普諾夫分析的方法是被用來發展適應法則去調整參數，並且根據李亞普諾夫穩定定理及可變結構控制，本論文將提出強健適應模糊滑動模式控制器，不僅可以讓追蹤誤差可以漸進的收斂到零，同時可以確保整個系統之穩定性。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可行性。

關鍵字

離散時間 ； 強健 ； 模糊

並列摘要

Generally, the robust characteristics and the stability of the uncertain systems mostly put emphasis on the continuous-time systems. In this thesis, a discrete-time robust adaptive fuzzy control scheme is proposed for a class of uncertain nonlinear discrete-time systems. The unknown nonlinear functions of the plant are approximated by the fuzzy logic system by means of some adaptive laws. In addition, in order to compensate for approximate errors, this thesis utilizes the variable structure control (VSC) with a sector. The Lyapunov synthesis approach is used to develop the adaptive laws to adjust parameters in the system. According to Lyapunov stability theorem and variable structure control (VSC), the proposed adaptive fuzzy sliding mode controller can not only guarantee tracking error, which is between outputs and desired values, to be asymptotically in decay, but also obtain the stability of the system. Finally, some examples and simulation results are provided to illustrate the feasibility of the proposed method.

並列關鍵字

discrete-time ； robust ； fuzzy

參考文獻

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