中央空調系統運轉耗能模擬與控制策略最佳化之研究

Abstract

本文以模擬計算方式，探討中央空調系統於不同運轉策略下，對系統總耗能的影響，並提出實務運轉可應用之方法。本文先以五個通用數學問題比較四種粒子群最佳化演算法的效能，以求解穩定性為主要考量，歸納得線性遞減慣性權重法較適合本研究應用，並使用此法解決後續之空調系統最佳化運轉策略問題。接著對中央空調系統運轉策略問題進行研究，將問題分為四項子題，分別為：冰水主機群負載分配、冰水主機與冷卻水塔聯合運轉、冰水主機與空調箱聯合運轉、以及完整之中央空調系統運轉，其中驗證了空調設備的耗電計算模式，建立並驗證冷卻水塔與空調箱濕盤管的性能簡化計算模式。本文所提出之冷卻水塔與空調箱濕盤管性能簡化計算模式，經驗證均優於前人所提之計算模式，可於較大操作條件範圍求得較準確的熱傳數據。而在系統運轉策略方面，獲得冰水供水溫度最佳化調整是最有效方案的結論，在本研究案例分析中，系統全年的用電量可減少862.3 MW•hr，節能率達14.85%，二氧化碳排放量亦可降低548.4 ton。此最佳冰水溫度與系統負載率呈線性關係，如此便可依據系統運轉的負載率，即時且容易地調整冰水供水溫度。

This thesis numerically investigates the power consumption of the centralized air-conditioning system under several operation strategies and then concludes a method to implement in practice. First, this study compares the performances of four updating rules of the particle swarm optimization through applying five mathematic problems. The linear-decayed inertia weight method is favorable for this study because of the stability of solutions searching. Then, four subjects, which are chiller-loading distribution, chillers and cooling towers cooperation, chilled-water and air-handler system cooperation and integrated centralized air-conditioning system operation, are specified to investigate the control strategies. The validations of the power consumption models of the air-conditioning components are accomplished. The simplified heat transfer models of cooling towers and wet finned-tube heat exchangers are also proposed and validated. The proposed simplified models can be implemented with a wide range and the predicting results are better than present models. The proposed operation strategy is optimal chilled-water supply temperature. In one sample case, the system operated under the proposed strategy can save the energy of 862.3 MW•hr and reduce the carbon-dioxide emission of 548.4 tons. The energy-saving rate can reach 14.85% compared with the energy consumption of the traditional operation strategy. The optimal chilled-water supply temperature can be correlated as a linear function of cooling load rate. Therefore, the chilled-water supply temperature can be adjusted easily and rapidly according to the system cooling load rate.