- 學位論文
繼電器回授系統鑑別之即時IMC-PID控制器應用於滿液式變頻冰水主機
Real-Time IMC-PID Controller of Relay Feedback System Identification Applied in Flooded VSD Chiller
摘要
本研究目的是發展出一有系統鑑別功能的PID控制器。期望研究成果能有效地推廣於工業界，並應用於各種工業系統。整個流程分為系統鑑別和PID控制兩部分。系統鑑別採用的是繼電器回授測試。本次研究是透過解析程序的輸出波形，對程序建立模型。其價值在於，整個過程只需要使用一次繼電器測試，又可以獲取最多的資訊。PID控制採用的是IMC-PID。其價值所在是，IMC-PID設計以強健控制和抑制擾動為出發點。只要選擇適合的IMC濾波器，就能達到設計控制系統的兩大目標，設定點追蹤與抑制擾動。實驗於滿液式變頻冰水主機結果發現，採用波形解析建立的模型會較傳統利用極限資訊建立的模型來得更準確；IMC-PID控制抗擾動性佳；且僅需花760秒就能達到目標值7℃，比Ziegler-Nichols PID調節法的1800秒更快追到設定點並達穩定。
並列摘要
This study aims to develop an advanced PID controller that provides a system identification function. The proposed PID controller can be applied to a wide variety of industrial implements. The controller can be separated into two parts: system identification and PID control. The identification method uses the relay feedback test to create a model. Here, model parameters are determined by analyzing process curves. The identification method only takes one test to obtain the most useful information. This PID controller uses an internal-model controller PID (IMC-PID). This IMC-PID controller’s value lies in the fact that it was designed with robust control and disturbance rejection as its main focuses. An appropriate filter is chosen to achieve goals of control system design: set-point tracking and disturbance rejection. The experiment was conducted on a flooded variable speed drive chiller. The results show that the proposed method identifies a model more accurately than the conventional identification method. This proposed IMC-PID controller also has better load disturbance ability than conventional IMC-PID controllers. This study compares the IMC-PID control method and the Ziegler-Nichols PID tuning method. The proposed IMC-PID method takes only 760 seconds to meet set-point 7℃, while the Ziegler-Nichols PID tuning method takes 1800 seconds, showing that the IMC-PID is faster and more stable than the Ziegler-Nichols PID.