變頻離心式冰水機節能效益之研究

A Study on Energy Saving Performance of Variable Frequency Drive Centrifugal Chiller

徐金輝(King-Huei Hsu)

指導教授 ： 卓清松

國立臺北科技大學/機電學院/冷凍空調工程系所/碩士(2006年)

摘要

由於離心式冰水機是中央空調系統中單一設備耗電最大的項目，對於建築物節能具有關鍵性的影響。本論文說明以變頻驅動的離心機式冰水機在台灣的氣候條件下操作，其COP值遠優於傳統的定頻機組。本研究過程中使用經ARI認證合格的電腦程式，對350冷凍噸的定頻和變頻離心機組各一台，分別在各種可能的負載、冷卻水進水溫度和冰水出水溫度條件下模擬冰水機的運轉數據，以分析、比較這兩種機型的COP值。研究結果顯示，若供應冰水機的冷卻水溫度從30℃降至20℃時，變頻機組在100%至40%負載之間操作的COP值與定頻機組的差異幅度達到70%。若配合能源管理手段，在低負載且空調空間無需顧慮相對濕度過高的情況，適度提高冰水出水溫度設定點，可更進一步提升冰水機的COP值。本論文的研究結果可提供這些專業人士在選擇離心式冰水機時重要的參考，以期更普遍應用變頻機組作為空調系統有效節能的手段。

關鍵字

離心式冰水機 ； 變頻 ； 節能

並列摘要

Centrifugal chiller is the single largest electrical load in central air-conditioning system. Energy efficiency of a chiller is critical to energy saving performance for a building. This thesis presents that the COP of a variable frequency drive (VFD) centrifugal chiller at operating conditions here in Taiwan is far better than a constant speed drive (CSD) chiller. An ARI certified computer program is used to simulate operation of two 350 tons centrifugal chillers, one is VFD and the other one is constant speed. Analyzed results show that COP of a VFD chiller operates between 100% and 40% load is up to 70% higher than that of the CSD chiller if ECWT drops to 20 ℃ from 30 ℃. COP can be further improved by resetting leaving chilled water temperature if relative humidity is not a concern. The conclusion of this thesis may provide some guidelines for those professionals when they make a selection of centrifugal chillers. Then VFD chillers may be more popularly applied in air-conditioning system design as an effective measure to achieve energy saving requirements.

並列關鍵字

centrifugal chiller ； VFD ； energy saving

參考文獻

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