本篇研究利用一簡單的數據驅動模型，提出在實際工廠中操作冷卻水塔變頻風扇策略。藉由工廠所提供的數據，建立一統計分析的模型來預測冷卻水塔的出口水溫，在基於此一出口水溫預測模型的建議風扇運轉模式，自動控制冷卻水塔的變頻風扇。
　　根據本篇提出的方法，可以使冷卻水塔的變頻風扇自動操作且維持出口水溫在一穩定的溫度。本篇研究利用虛擬的工廠數據模擬，來估算利用本方法比較原本工廠的操作可以節省多少能源，其結果顯示尚有很大的節能空間。在本篇研究中也提出了於現場利用此一出口水溫預測模型來實際操作冷卻水塔變頻風扇的實驗，以驗證模型的準確性與基於模型操作冷卻水塔變頻風扇的實用性。在未來，此一方法將上線於工廠中的冷卻水塔變頻風扇做為實際應用。
　　在本篇研究結果中，利用本篇研究提出的方法操作冷卻水塔變頻風扇，可有效地長時間維持水溫在一設定溫度，而且模型預測與實際出口水溫的誤差小於0.2°C。在本篇研究提出的基於模型操作方法，相較於原來實際工廠中的操作模式，約可節省50%-90%的能源消耗。預期未來將可推廣應用在類似的工業用冷卻水塔變頻風扇上，增進能源的使用效益。

　　This study presents a strategy to operate the variable frequency drives (VFDs) fans on cooling towers in industry, by a simple data-driven model. The operation data of cooling tower is provided by a practical plant. Using the data, a statistical analysis model can be built to predict the outlet water temperature of the cooling tower.
　　According to the model prediction, it is available to control the VFDs fans automatically and maintain the outlet cooling water at a steady temperature. The model-based operation of the virtual plant simulation is used to estimate how much energy can be saved, different from the original operation in the plant. The results of simulation show that there is large room for energy conservation. In order to check the reality of the statistical analysis model, the experiments of the model-based operation are also presented in this study. In a final target, the method would be applied to operate the industrial cooling tower fans in practical plant.
　　The results show that the outlet water temperature will reach the set point and the error of model prediction is less than 0.2°C. According to preliminary estimates, compared with original operating mode, it can save 50%-90% energy by the method presented in this study.

ABSTRACT i
Tables of Contents ii
List of Figures iii
List of Tables iv
CHAPTER 1 INTRODUCTION 1
1.1 MOTIVATION 1
1.2 PAPER REVIEW 3
CHAPTER 2 THE COOLING TOWER 7
2.1 THE CONTROL PROCESS 7
2.2 INTRODUCTION OF THE COOLING TOWER 8
2.3 MEASURING POINTS OF THE COOLING TOWER 11
CHAPTER 3 MODELS AND METHODS 14
3.1 PHYSICAL MODEL 14
3.2 OUTLET WATER TEMPERATURE PREDICTIVE MODEL 16
3.3 MODEL-BASED OPERATION METHOD 20
CHAPTER 4 RESULTS AND DISCUSSIONS 23
4.1 COOLING TOWER OUTLET WATER TEMPERATURE MODELING 23
4.2 THE VIRTUAL PLANT SIMULATION OF MODEL-BASED OPERATION 25
4.3 EXPERIMENTS OF MODEL-BASED OPERATION 30
CHAPTER 5 CONCLUSIONS 35
REFERENCE 36

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