數位式直流伺服馬達模糊PID位置控制器之研製

Abstract

本論文利用模糊PID控制器來進行伺服系統的位置控制，順利解決PID控制 器和模糊邏輯控制器應用於直流伺服馬達位置控制上所衍生的問題，進而 提昇系統整體的控制品質。研究的重點，將著重於模糊邏輯與PID控制器 的結合方法和設計程序，並分析模糊PID 控制器的性能。模糊PID控制器 是由模糊決策系統和PID控制器所結合而成，因此控制器設計的方法來自 於兩個部份：一是為傳統控制理論的設計方法與技巧；另一是來自專家經 驗和知識。其中專家的經驗法則是用來建立知識庫；至於歸屬函數的定義 和設計則是以PID 控制器的設計方法作為依據而逐步建立。由於控制器是 根據系統響應採行區段設計，並以模糊邏輯結合之，不僅可使控制器的性 能大為提昇,而且使得控制器的設計過程變得十分簡便。本論文所進行的 模擬與實作，著重於模糊PID 控制器的性能分析並與在工業界最被廣泛使 用的PID 控制器相比較。在線性及非線性的工作環境中針對直流伺服馬達 的位置控制進行系統響應和穩健性測試，以驗證出模糊PID控制器的性能 。 This thesis applies a fuzzy PID controller to realize the position control of a dc-motor position servo system. It solves the problems of the individual PID controller and the Fuzzy logic controller applied on position control of a dc motor and furthermore increases the performance of the whole system. The design methods and procedures of the combination of fuzzy logic and PID controller are emphaseized. Also, the performance of fuzzy PID controller is studied. The fuzzy PID controller consists of a fuzzy decison system and a PID controller. Therefore, the controller design method comes from two parts: one is the conventional control theory and design technique, the other is the experience and knowledge of the experts. The knowledge base is formed from the expert's experience and definition of membership function is based on PID controller design method. Since the controller design depends on the system response, it uses block design method and links these blocks by fuzzy logic. Not only it increases the performance of controller drastically, but also simplifies the process of the controller design. Simulation and implementation are focused on the performance analysis of the fuzzy PID controller and the comparison of the fuzzy PID controller with the conventional PID controller which is widely used in industry. The response and robustness tests of a dc motor position servo system are also performed with respect to linear and nonlinear enviroments to demonstrate the performance of fuzzy PID controller.