金屬芯印刷電路板設計對高功率發光二極體的散熱影響

吳昆財(Kun-Tsai Wu)

指導教授 ： 蕭述三

國立中央大學/工學院/機械工程研究所碩士在職專班/碩士(2015年)

摘要

目前發光二極體在固態照明上的應用越來越廣，可以應用在室內照明、戶外照明、背光源、汽車照明、交通號誌燈及其它產業等。當LED的應用趨勢愈普及化，意味著LED的效率正在逐步提升當中。由於LED的輸入功率只有30%轉換成光，70%轉換成熱，因此，LED熱管理的問題更受到重視。若想要降低LED的接面溫度與熱阻值，其中最重要的一項是電路板的導熱銅箔層設計。
本研究最主要的目的是設計一款最佳化的金屬芯印刷電路板，可以降低來自於晶片的熱。使用散熱模擬分析、散熱實驗，對金屬芯印刷電路板散熱性能做探討。透過SolidWorks Flow Simulation軟體的分析與實驗結果的比對，要先確認分析的合理性，再尋找散熱解決對策。
比較六款不同金屬芯印刷電路板的導熱銅箔層設計，並藉由接面溫度及熱阻來評估在高功率LED模組上的散熱效能。從散熱模擬分析及散熱實驗結果顯示，由於Type-3導熱銅箔層的熱電耦合設計和具延伸面積設計，LED模組呈現出大約最低的接面溫度65.73°C與熱阻值17.21°C/W。依據模擬結果與散熱量測可以確認基板的幾何型式直接影響到LED的接面溫度及熱阻。

關鍵字

發光二極體 ； 接面溫度 ； 熱阻值 ； 電路板的導熱銅箔層設計 ； 熱電耦合設計 ； 延伸面積設計

並列摘要

The light-emitting diodes (LED) in the application of solid-state lighting is interested. LEDs one can be used as indoor lighting, outdoor lighting, backlighting, daytime running light, traffic light and the other industries, etc.. When the trend of the increasing popularity of LED applications, the efficiency of LED has also been increased gradually. Due to only 30% of the input power been converted to light and nearly 70% been converted to heat. The thermal management issue of the LEDs become important and crucial. To reduce the junction temperature and thermal resistance, one important issue is copper foil layer design of Printed Circuit Board.
The main purpose of this study is to design an optimizing Metal Core Printed Circuit Board in order to reduce the heat from the chipset. This work investigates the cooling ability of the MCPCB by thermal simulation analysis and thermal experiments of LED. This study uses commercial software, SolidWorks Flow Simulation, to analyze the temperature field and the results are compared with experimental data to verify the simulation analysis.
Six different copper foil design of MCPCB were compared. The junction temperature and thermal resistance, were used to evaluate the thermal performance on high power LED module in this study. From the thermal simulation analysis and thermal experiments results, the LED module showed a minimum junction temperature and thermal resistance at about 65.73°C and 17.21°C/W due to the thermoelectric coupling design and extended area design of the copper foil layer in Type-3. According to the simulation results and temperature measurement, we can make sure that the substrate geometry has directly effects on the junction temperature and thermal resistance of an LED.

並列關鍵字

light-emitting diodes ； junction temperature ； thermal resistance ； copper foil layer design of Printed Circuit Board ； thermoelectric coupling design ； extended area design

參考文獻

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