本研究使用彰濱外海兩座海測塔從2015年至2018年風速資料與颱風資料，並參考彭佳嶼測站之風向資料選取東北季風案子，利用小波轉換做為主要分析方式，並與總體經驗模態分解法、紊流強度等相做比較，試圖找尋因地形阻隔而造成之大氣紊流特性。
將收集後之風速資料挑選十一段東北季風選取頻率上下限為5×〖10〗^(-3)Hz至1×〖10〗^(-3)Hz做小波轉換一次分析後將其大氣紊流較強時間選取出來做頻率上下限為5×〖10〗^(-3)Hz至3.33×〖10〗^(-3)Hz之小波轉換二次分析，並將其所得到之頻率能量做無因次化得到後之結果相加平均，由結果可以得知山脈地形對於如東北季風等大氣紊流有造成直接的影響進而導致特徵頻率的出現以及類似於周期性尾流的出現，並且因為地形效應之因素導致台灣海峽之風速與台灣東部之風向有直接性的關聯。
關 鍵 字：大氣紊流特性、小波轉換、總體經驗模態分解法、頻譜圖

In recent years, countries have emphasized the importance to the wind energy industry. Wind turbine blades are strongly influenced by turbulence structure. Small scale turbulence fluctuation are the main cause of structure damage. This heightens the importance of understanding the characteristics of wind turbulence to prevent wind turbines from damages. This study uses wind speed data and typhoon data from 2015 to 2018, and refers to wind direction data from Pengjiayu Station in Northern Taiwan to predict the northeast monsoon case.
Wavelet transform can provide the relationship between time domain and frequency domain. The upper and lower limit frequency can be adjusted according to needs. This study attempts to find the characteristics of atmospheric turbulence caused by terrain obstruction. Therefore, the height of the mountain is used to normalize the northeast monsoon frequency obtained by the wavelet transform. The result of the wavelet transformation is compared with the turbulence intensity and EEMD. The results also point out that the wind direction at Pengjiayu Station is directly related to the wind speed in the Taiwan Strait due to terrain obstruction. Because of the terrain obstruction, the atmospheric turbulence flowing through the obstruction has a characteristic frequency.
Keywords: Offshore wind power, Atmospheric turbulence, Wavelet transform, EEMD, turbulence intensity

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