結合QFT/H∞控制理論設計光學循軌伺服系統控制器之研究

Abstract

本論文中的重點在原有光碟機系統的基本架構之下，結合QFT以及H∞最佳強韌控制理論來設計循軌伺服系統控制器。目的就是針對一個具有參數變動的受控體，先利用QFT控制理論針對我們制定的系統輸出規格來定義上邊界函數、下邊界函數以及前置濾波器，之後再藉由 H∞強韌控制理論，將制定的系統輸出規格轉換成權重函數，並利用由K.Glover和J.C.Doyle等人所提出的李卡提方程式(Riccati Equation)的解法來找出控制器，最後再藉由前置濾波器讓整個光碟機循軌伺服系統的輸出響應能落在上下邊界的範圍內，以完成整個設計的過程。

This dissertation studied the tracking servo control design of optical pickup using QFT/H∞ robust control theorem. For a SISO plant with parameter variations, we first used QFT control theorem to define upperbound function, lowerbound function and Prefilter based on system output specifications. Secondly, we transferred system output specifications to the weighting functions by using H∞ robust control theorem. According to solve the Riccati Equation, we can obtain the controller to meet system output specifications. Finally, a prefilter is designed to fit the output response of tracking servo control in optical pickup settling between the range of designed upperbound and lowerbound.