使用頻域方法設計量化強健控制系統

Design of Quantitative Robust Control Systems Using Frequency Domain Approaches

應誠霖(Chen-Ling Ying)

指導教授 ： 林志民

元智大學/工程學院/電機工程學系/博士(2002年)

摘要

本論文介紹等效擾動抑制設計方法，使系統達到量化強健控制性能。此方法是將受控體參數最大變動量轉換成擾動量，並將系統最大容忍變動量轉換成具體的輸出響應。輸出量化設計規格定出後，利用靈敏度的觀念在反尼可士圖上計算出特定頻率之邊界函數值。並將前人所提出等效擾動抑制設計方法擴展至可以處理穩定和不穩定加上極小相和非極小相之多變數系統。經由在反尼可士圖上做迴路函數整形，最後可以得到一個使系統量化強健控制器。
本論文亦提出在不確定性多變數回授系統強健解耦演算方法，對二自由度控制系統而言，應用量化回授理論設計回授控制器以達到量化強健性，再利用解耦模式匹配方法設計前置濾波器以達到輸出入解耦性能。
另一方面，提出多變數量化強健線性二次最佳控制的合成方法，結合線性二次最佳化控制與量化回授理論 來設計量化強健性最佳控制系統。
最後本論文提出四自由度架構之控制和診斷統合設計方法以同時達成控制性能及故障診斷能力，其中二自由度控制器是由回授控制器和前置濾波器組成，另外二自由度之故障診斷器用於故障偵測。設計過程中利用伴隨理論技巧決定閥值以符合診斷性能。

關鍵字

量化強健控制 ； 等效擾動抑制 ； 量化回授理論 ； 解耦特性

並列摘要

In this dissertation, the equivalent disturbance rejection (EDR) design method is introduced to achieve quantitative robust control performance. Using this design method, the maximum variations of the uncertain plant can be transferred to an equivalent disturbance, and the maximum variations of the system tolerance can be transferred to a specified output response. The quantitative specification is then formulated in the inverse Nichols chart by calculating the values of bound functions at some specified frequencies using the sensitivity concept. Previous EDR design method is extended to handle stable and unstable systems plus both minimum and non-minimum phase multivariable systems in this dissertation. Finally, by loop shaping in the inverse Nichols chart, a robust controller can be designed to achieve quantitative robust performance.
This dissertation also presents a design algorithm of involving robust decoupled control of uncertain multivariable feedback systems. For two-degree-of-freedom (2-DOF) system, quantitative feedback theory (QFT) is applied for feedback compensator design to achieve quantitative robustness. A decoupled model matching approach is employed for prefilter design to achieve input-output decoupling performance.
On the other hand, the synthesis methodology of multivariable quantitative robust linear quadratic optimal control system is developed. Wiener-Hopf linear quadratic optimal control is introduced and is then incorporated with quantitative feedback theory robust control design technique to achieve the quantitative robust optimal control.
Finally, an integrated control and diagnostic design method is proposed which uses the four-degree-of-freedom scheme. The robust controller presents a two-degree-of-freedom structure including the feedback controller and the prefilter. For failure diagnosis, the diagnostic filters are chosen to perform the fault detection. The adjoint technique is applied for threshold value determination to meet the diagnostic performance.

並列關鍵字

Quantitative robust control ； Equivalent disturbance rejection ； Quantitaive feedback theory ； Decoupled performance

參考文獻

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