強健設計的一些實用方法研究

Robust Design by Some Practical Methods

楊忠山(Jong-Shang Yang)

指導教授 ： 韓光渭 ； 林志民 ； 韓國璋

元智大學/工程學院/電機與資訊工程研究所/碩士(1997年)

摘要

H∞ 最佳控制理論和QFT是兩種非常有用的強健控制設計方法，本文中，我們對這兩種方法作了一些探討，以期能以較簡單的設計程序，設計出儘可能低階的控制器，以利控制器的實現。
首先，我們改進了Besson和Shenton兩位先生在1997年提出的 "以混合H∞ 與參數空間法之互動式控制系統設計(Interactive Control System Design by a Mixed H∞ - Parameter Space Method)"，使得求解控制器的過程中，可減少試誤的次數，使這套方法更為實用。
其次，大家都知道QFT是很實用的一種強健設計方法，但設計過程即使對一個有經驗的工程師來說還是太煩瑣，所以，我們提出不管相位資訊只在意大小的QFT設計方法，雖較傳統的QFT方法保守，但過程實在是簡單太多了。
最後，我們介紹了在前幾年，許多前輩所做的將QFT的問題轉變成混合H∞ 的設計問題，以得到一個數學解，但所得的控制器階數可能會高過我們所能接受的程度，所以我們用前面所提的方法來得到一個較低階，且能滿足原QFT規格的控制器。
文中，我們就實際的一些例子，以前述的方法設計，模擬結果顯示這些設計方法是有效而可行的。

關鍵字

H∞最小化問題 ； 量化迴授理論 ； 參數空間設計法

並列摘要

H∞ optimal control theory and QFT provide two powerful as well as practical robust design techniques. In this thesis, we apply these theories to design controllers of lower order. In addition, the design procedures proposed here are simpler.
Firstly, we improve the design method in the paper, "Interactive Control System Design by a Mixed H∞ - Parameter Space Method", proposed by Besson and Shenton in 1997, by reducing the adjustment cycles in the design procedures. For doing so, it becomes easier and more efficient to design a robust controller by this method.
Secondly, it is well known that the design procedures of conventional QFT method are somewhat tedious even for a control engineer with QFT design experiences. Here we propose a modified QFT design method where the phase information is not considered. It is simpler, however more conservative, than that of conventional QFT approach.
Finally, we present a method of transforming QFT problem into an H∞ formula for possible execution of a QFT design, and thus obtain a mathematical solution, which is discussed in recent years. However, the order of the controller obtained may be too high to be accepted, thus we will apply the above mentioned design methods to obtain a lower order controller which the QFT specifications are met.
Illustrative examples are given to show that the design results can meet the specifications by the above proposed methods.

並列關鍵字

mixed H∞ sensitivity optimization ； QFT ； parameter space design method

參考文獻

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