高功率LED之主動式散熱控制技術研究

Abstract

本研究旨在開發LED主動式散熱技術，提供高功率LED在特殊高溫環境下(高頂建築、礦坑、工廠等)散熱所需。本研究利用DC 12V(48W)變頻壓縮機作為主動製冷元件，配合LED燈具設計，將冷凝器、膨脹閥及蒸發器等元件，和燈具硬體做結合，將LED照明時所產生的熱量散發至環境中。蒸發器固定於150W LED鋁基板上，透過銅管內冷媒循環傳遞熱量，將熱量從150W LED鋁基板傳導至冷凝器。冷凝器固定於燈具外殼的內壁，熱量從冷凝器傳導至燈具外殼，最後透過自然對流方式來散熱。另外，我們將量測到的LED鋁基板溫度進行回授控制，利用壓縮機變頻控制技術改變壓縮機的轉速，達到控制LED鋁基板溫度且節省壓縮機運轉耗能之目的。在25℃的環境下，壓縮機平均耗能為26W，可將LED鋁基板溫度維持在50℃，壓縮機的COP達5.77，LED燈泡發光效率為85.2 lm/W；而在高溫40℃的環境下，壓縮機平均耗能為48W，LED鋁基板溫度維持在50℃，壓縮機的COP達3.13，LED燈泡發光效率為77 lm/W。

The main objective of this study is to develop LED with active-cooling technique, designing an interior droplight, which can provide high power LED for the purpose of heat dissipation in high temperature environment (e.g. mines, factories and desert areas). This study uses DC 12V compressor as active-cooling component, with the interior droplight design, integrating the condenser, expansion valve, and evaporator into a system. The aim of applying this system is to dissipate the heat from the 150W LED into the environment. In addition, the temperature measured by the aluminum PCB is then processed for feedback control. The inverter technology is used to change the rotating speed of the compressor, to control the temperature of aluminum PCB, and to save power while the compressor is in operation. The LED aluminum PCB is controlled at around 50oC under ambient temperature 25℃, and the average power consumption of the compressor is 26W.The COP is 5.77, and the overall LED efficacy is about 85.2 lm/W. At 40℃, the average power consumption of the compressor is 48W.The COP is 3.13, and the overall LED efficacy will be reduced to about 77 lm/W.