- 學位論文
機櫃冷卻系統之多變量溫濕度控制研究
Multivariable Control of Temperature and Humidity for Rack Cooling System
摘要
本研究發展一個多輸入多輸出(MIMO)之控制策略，可以同時控制兩輸入(風扇轉速與壓縮機轉速)和兩輸出(溫度與濕度)之控制系統，應用在資料中心密閉式機櫃冷卻系統。使用線性二次型高斯(LQG)技術設計出MIMO控制器，實驗測試結果，此控制器具有良好的追蹤目標值與抗干擾能力。 研究中利用可程式控制器(PLC)監控冷卻系統之狀態點，並根據出風條件與實際出風狀態之變化，以電腦進行多變量控制運算，同時控制壓縮機與風扇轉速，使系統運行於適合之壓縮機頻率與風機轉速下，有效地維持溫度與濕度並達到節能效果。而出風條件則以ASHRAE TC 2011年機房環境定義中規範之建議值內，並以PUE、RCI與RTI等指標進行評估。 由實驗結果得知，於最大負載時PUE值為1.46，此結果與國內機房實際量測PUE平均值為1.9，和美國ASHRAE之300RT等級之標準PUE值為1.52相較之下，其機櫃冷卻系統之電能使用效率皆優於國內外之案例，且RCI可穩定於100%，RTI則因機櫃設計方式因而可達到100%為理想等級。
並列摘要
This study developed a multi-input multi-output (MIMO) control strategy for simultaneously control two inputs (fan speed and compressor speed) and two outputs (temperature and humidity) control systems, applications in the rack cooling system. The linear quadratic Gaussian (LQG) technique was used in designing the MIMO controller. The test results demonstrated that the MIMO controller has a good command following and disturbance rejection. The rack supply air temperature and humidity are according to 2011 ASHRAE thermal guidelines for data processing environments. The results show that the PUE can reach 1.46 at maximum cooling load point and the RCI stable in 100%. RTI also stable in 100% by closed (In-Row) system. This maximum PUE is much better than the average PUE 1.9 of the surveyed data in Taiwan also better than the PUE1.52 of baseline case per ASHRAE Std.-90.1 for a 300RT cooling system.