本研究以手機無線充電器之線圈為對象，使用田口法搜尋最佳化線圈的參數，包含發射端線圈外直徑(D_o^Tx)、發射端線圈線材粗細(D_w^Tx)、接收端線圈外直徑(D_o^Rx)以及接收端線圈線材粗細(D_w^Rx)，所得D_o^Tx、D_w^Tx、D_o^Rx與D_w^Rx等參數之最佳值分別為75 mm、1 mm、55 mm與1 mm。為驗證田口法所設計之最佳化線圈尺寸，吾人再以基因演算法進行線圈參數的搜尋，所得D_o^Tx、D_w^Tx、D_o^Rx與D_w^Rx等參數之最佳值分別為80 mm、1.3 mm、55 mm與0.8 mm。由結果得知，雖然兩種方法之D_o^Rx維持不變，但田口法所得D_o^Tx與D_w^Tx可分別縮小5 mm與0.3 mm，且系統傳輸效率增加3.7%，唯D_w^Rx需增加0.2 mm。因此，吾人選擇以田口法所得線圈參數製作無線充電系統，並對容量2200 mAh鋰電池進行充電測試，再與Magsafe無線充電器進行實驗比較。雖然所完成之手機無線充電實驗的整體系統效率僅61.75%，且感應線圈尺寸比Magsafe充電器增加20 mm，但該線圈可增加傳輸效率14.47%且傳輸距離可增加2.5 mm，以及充飽電可節省約10分鐘。

The purpose of this study is to investigate wireless charging coils for mobile phones based on Taguchi method for searching optimal parameters of charging coils including outside diameter of transmitting coil (D_o^Tx), width of transmitting coil (D_w^Tx), outside diameter of receiving coil (D_o^Rx), and width of receiving coil (D_w^Rx). The obtained results of D_o^Tx, D_w^Tx, D_o^Rx and D_w^Rx with Taguchi method are 75 mm, 1 mm, 55 mm, and 1 mm, respectively. To verify those values obtained by Taguchi method, genetic algorithm is then applied to search for the optimum design of coils. The obtained results of D_o^Tx, D_w^Tx, D_o^Rx and D_w^Rx with genetic algorithm are 80 mm, 1.3 mm, 55 mm, and 0.8 mm, respectively. It is found that the Taguchi method yields smaller outer diameter and width of the transmitter coil than the Taguchi-GA method, and the outer diameter and width of the transmitter coil decreases by 5 mm and 0.3 mm, respectively. However, the genetic algorithm is able to shorten the receiving coil width by 0.2 mm compared to the Taguchi method, but the receiving coil outer diameter remains the same. Nonetheless, the system efficiency increases by 3.7%. Therefore, the optimal parameters obtained from the Taguchi method are used to design coils for wireless charging mobile phones with a rated lithium battery of 2200 mAh. The system capabilities of the designed wireless charger are tested, and the obtained data are compared to Magsafe charger. The efficiency of the designed wireless charging system for mobile phones is only 61.75%, and the coil dimension is 20 mm larger than that of Magsafe charger. Nevertheless, the transmission efficiency of the designed coils increases by 14.47 %, the distance of the wireless transmission increases by 2.5 mm, and the amount of time needed for a full charge with the designed coil reduced by 10 minutes

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