此篇論文進行了風洞實驗量測的研究，研究目的為在不同的非穩態入流條件下，模型風力發電機的發電效率和尾流特性的分析比較。過去幾年在風洞實驗上，大多數學者使用不變的振盪入流條件，而本篇論文相較於以往不同，本實驗研究強調在有正弦波變化的入流速度條件下（例如:風速為5至8.2 m/s）的測量值（包括電流，葉片轉速和尾流的速度分量），估算了五個電阻，其電阻值分別為15、17.9、19.7、23.4和25.1歐姆下的功率係數，並且得到瞬時的最大機械功率係數為0.47。使用週期為30秒的正弦入流(週期性變化入流)的速度，量測電流，葉片轉速，葉片尖端速度比和功率係數變化分佈，發現電流和葉片轉速的變化幅度（也與葉片尖端速度比相關）隨電阻值的增加而減小，這項實驗結果表明當電阻值越大，入流速度變化對於風力發電機的運行影響較小。而關於尾流特性測量的結果歸納出二項重點。第一點為由於週期性變化入流的風速從上到下變化，其尾流的湍流強度（TI = 0.055）大於振盪性入流的湍流強度（TI = 0.025）。第二點為通過在±4波數處進行傅立葉轉換，其目的為了濾除每個測量點上120秒瞬時速度分量的週期性變化的入流特性，濾波後的尾流具有類似於振盪性入流條件下的特徵。

This study conducted wind tunnel experiments to study the power generation efficiency and wake characteristics of the model wind turbine under different unsteady inflow conditions. Unlike most previous wind tunnel experiments with non-varying oscillatory inflow conditions, this study emphasized measurements (including electrical current, blade rotating speed, and turbulent wake velocity components) under the inflow velocity with a sinusoidal variation (e.g., 5 to 8.2 m/s). The power coefficient under five resistances of 15, 17.9, 19.7, 23.4, and 25.1 ohms is estimated, with the instantaneous maximum mechanical power coefficient of 0.47. The electrical current, blade rotating speed, tip speed ration, and power coefficient have varying distributions strongly associated with the sinusoidal inflow(periodic inflow)velocity variation that has a period of 30 seconds. The magnitude of the variation in the electrical current and blade rotating speed (also associated with tip speed ratio) is found to decrease with an increase of the resistances, which indicates that the inflow velocity variation causes a small effect on the turbine operation connected with a larger resistance. The statistics of the wake measurements summarized two important points. The first point is that the wind velocity of the periodic inflow changes from top to bottom, so the turbulence intensity of its wake (TI = 0.055) is greater than twice that of the oscillating inflow (TI = 0.025). The second point is that the periodic inflow characteristics from 120-second instantaneous velocity components at each measurement point can be filtered out through Fourier transform at ±4 wavenumbers. The filtered wake has characteristics similar to that under the oscillatory inflow condition.

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