冰水主機與冷卻水塔控制策略之耗能分析

The Energy Analysis for Control Strategy of Chiller and Cooling Tower

李奕軒(Yi-Hsuan Li)

指導教授 ： 李文興

國立臺北科技大學/機電學院/能源與冷凍空調工程系碩士班/碩士(2009年)

摘要

目前現行的空調系統中，冷卻水塔的控制方式大多是定頻或變頻來搭配不同的控制模式，較常見的運轉模式為固定趨近溫度以及固定水塔出水溫度，而許多廠商無法在不同的負載模式下做出正確的參數設定，往往都以經驗做為各項參數的設定依據，因此參數對耗能的影響便成為本研究的重要目的。 　　主要將分別針對冰水主機與冷卻水塔的數學模型進行模擬分析，將實務上所使用到的控制策略以模擬的方式呈現，將對固定趨近溫度以及固定水塔出水溫度做比較，將中央空調各元件的運轉特性搭配廠商之資料作為依據，以控制及數值模擬分析等相關學理，建立理論計算模式，進行系統分析；而藉由各項分析模擬結果，並分析在不同的環境條件下，各種模式的參數設定，以達到降低空調耗電及節約能源的目的。 　　對於夏季系統佳化之最小耗電與控制策略的比較，將由單台主機水塔運轉的兩種案例的八個不同策略設定值之模擬結果可得知，系統的佳化較其它策略大約可節省系統總耗電量的0.05%~2.13%，而多台主機水塔聯合運轉的部份則約可節省整體系統總耗能的0.3~2.32%，而在此外氣條件及負載條件之下，固定出水口溫度策略設定值為31℃時較為節能，而固定趨近溫度設為3℃時亦可得到較佳的節能效果，在春季的單台運轉系統的系統佳化較其它控制策略大約可節省系統總耗能的0.09%~10.17%，秋季的單台運轉系統的系統佳化較其它策略大約可節省系統總耗能0.27%~4.97%，由上述所分析的結果可得知，若在不同的環境等條件之下，若可以將策略設定值設定於適當值，則必定可以達到節能之目的。

關鍵字

控制策略 ； 冷卻水塔 ； 冰水主機

並列摘要

In current air condition system, the chiller control by fixed frequency or variable frequency. However, many manufacturers difficulty to make the correct parameter enactment under the different load mode, and usually take experience as various parameters on basis. In this research, the influence in parameter to consumes energy is the important purpose.
　　At first, we aim at the mathematics model of chiller and cooling tower to carry on emulation analysis respectively, and actual situation up the control strategy used is presented with the way of emulation, then fixed the tower approach temperatures and fixed the tower outlet water temperatures to compare. Second, to stand on the operation characteristic of each component of central air condition and the function data that manufacturer provide, and build up the model of the theories calculation based on control and the number imitates analysis. Third, carry on system analysis also concert to physically revolve a case to inquire into the theoretical calculation pattern. Finally, the various analysis imitate a result and inquire into an energy efficiency, and analyze under the different environment condition, the parameter enactment of various mode, to reach the purpose that to reduce the consumption of an air condition and energy saving.
　　To compare with the system of optimization methodology and control strategy in summer, the results of eight control value of the two case in chiller and cooling tower operated, to the system optimization methodology can save 0.05 to 2.13% total system power compared with the other control strategy. In a multiple chiller and cooling tower system operated, the system optimization methodology can save 0.3 to 2.32% total system power compared with the other control strategy. In this climatic conditions and system cooling load, when fixed the tower outlet water temperatures control value on 31℃ will to reduce the energy consumption as well, and when fixed the tower approach temperatures control value on 3℃ will to reduce the energy consumption as well. The chiller and cooling tower system operated that the system optimization methodology can save 0.09 to 10.17% total system power compared with the other control strategy in springtime, and the system optimization methodology can save 0.27 to 4.97% total system power compared with the other control strategy in fall. By the analysis, in the different environmental condition, we can use the suitable for control values, and will certainly to reduce the energy consumption as well.

並列關鍵字

Control Strategy ； Cooling Tower ； Chiller

參考文獻

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