在採用田口實驗計畫法前，本研究參數設計必須採用五個合適的設計參數，分別是鰭片的數目、鰭片的厚度、鰭片的高度、散熱鰭片基底厚度、表面輻射材質等5個可控制因子，每個因子分別有4個水準做參數設計，以降低LED路燈之最高溫度。
　選用田口實驗計畫法中的Ｌ16(45) 直交表來設定各組參數值，並利用COMSOL Multiphysics模擬軟體實際模擬，將會取得16組模擬結果，再將模擬結果放入直交表中，利用直交表的設計和變異數的分析，找出實驗中主要效應因子為何，以及各個控制因子對回應值的關係，將1024次模擬簡化為16次，讓設計者在較短的時間內即可獲得較佳的設計參數。
　 初始設計之模擬可得狀況之最高溫度為48.817℃；利用田口實驗計畫之望小特性分析計算後，所得預測最佳設計參數利用COMSOL Multiphysics模擬，可得預測最佳設計參數狀況之最高溫度為37.321℃，鰭片最高溫度獲得明顯下降。本研究確實減少散熱鰭片的開發時間與設計成本，希望對LED路燈散熱設計有所幫助。

Before executing Taguchi method, we must estab¬lish the five parameters such as the number of fins and the fin thickness, the fin height, the fin thickness of substrate, the radiation material on surface. First, the above five parameters must be determined. Next, these parameters are divided into four levels separately in order to reduce the maximum temperature of LED street light .
This research using Taguchi Method makes the optimization of LED street light heat sink easier whereas the simulation times of the 5 parameters and the 4 levels of each parameter will be in total 1024 times. We establish a product that can effectively re¬duce simulation times to 16. The maximum temperature of LED street light is lower than all of probable combination exactly.
The original design of heat sink without optimization by Taguchi method, the maximum temperature of heat sink is 48.817℃. With the optimal optimization design we can reach the maximum temperature is 37.321℃,the temperature of sink is significantly decreased. Moreover the optimization by Taguchi method design can get the best construction in a short time. Therefore, this research for the cooling components decreases development time and the cost of production. We believe this research will be helpful for thermal design of LED street light.

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