- 學位論文
利用太陽電池驅動壓縮機之空氣取水技術研究
Capturing water from air using solar PV-powered DC Compressor
摘要
本研究旨在開發空氣中取水的機制，藉由系統識別後的取水系統，控制其適當蒸發器凝結面溫度與通過凝結面風速，來達到最高的取水效率。除探討影響取水量的因素，亦進行戶外實測。本研究首先設計取水系統機構與熱泵系統，除設計可調角度以利太陽能板發電外，並將取水系統所排出之冷風吹至太陽能板。利用實驗進行取水系統動態模型識別，並以此模型進行控制系統的設計與分析，來控制蒸發器凝結面溫度接近露點。由模擬與實驗結果，在大氣溫度範圍25℃~35℃、相對溼度40%~80%、蒸發器風扇風速1.0m/s~3.5m/s間，控制效果良好，在三分鐘內皆可使凝結面溫度之控制誤差值小於0.5℃。本研究並進一步來探討蒸發器凝結面溫度與蒸發器風扇風速對取水量的影響。在實驗條件溫度範圍25℃~35℃、相對溼度40%~80%、蒸發器風扇風速1.0m/s~3.5m/s、dTset=2℃~6℃時，發現在凝結面溫度設在露點下4℃，風速設於2m/s時，取水的效率最高，達相對省電與高熱機效率。最後進行戶外實驗，結合太陽能發電能量管理系統與取水系統進行實測，結果發現，不論在晴天或雨天時，取水系統都能精確控制蒸發器凝結面溫度。在白天高溫與傍晚低溫時，比較兩者間COP、取水所需時間與耗電量，發現傍晚時取水系統有較佳表現。
並列摘要
This research is to develop water-capturing technique. Through system identification of water-capturing device, the condensed surface temperature of evaporator and the windspeed of the evaporator fan can be controlled to make the optimum water-capturing efficiency. First, the water-capturing device mechanisms and heat-pump system are designed for optimum operation. Second, by system identification, the system dynamic model can be obtained to design control parameters. From simulation results, the control can work well during the Ta=25℃~35℃, RH=40%~80%, wind speed of evaporator fan=1.0m/s~3.0m/s. And the error is less than 0.5℃ in 3 minutes.Third, within the Ta=25℃~35℃, RH=40%~80%, the system can reach the high water-capturing efficiency, power-saving and high COP when it operate at wind speed of evaporator fan 2.0m/s and the dTset=4℃.Finally, the outdoor experiments of the combination of PV power system and water-capturing system is done to verify its feasibility. From the experiment results, the whole system including PV power system and water-capturing system can work well day and night. And the whole system has the best performance when it works at night.