隨著智慧監測技術的發展，低功耗感測器在風能設備、旋轉機械與離岸結構中逐漸普及。為降低電池維護成本並提升系統自足性，發展具備低頻能量擷取能力的壓電能量獵能器成為一項重要研究課題。本研究針對低速旋轉環境（如離岸風機）設計一具雙自由度之壓電能量獵能系統，透過非接觸式磁力激發與機械升頻轉換結構，使其具備寬頻響應特性與高功率輸出潛力。
本研究採用折回式懸臂樑架構，結合偏心擺裝置進行週期性激發。理論方面以能量法推導系統動態方程，包含偏心擺旋轉運動、磁力作用模型與壓電耦合項，建立完整耦合模型。為提升模擬效率與可解釋性，進一步提出傅立葉餘弦展開之解析解法，並同時建構數值模擬流程。模型可輸出壓電片電壓與功率預測結果，並能依磁力倍頻分量分析模態貢獻。
實驗部分搭建實體系統，量測末端質量、剛性、阻尼、耦合係數與內電容等參數。使用雷射位移計與高速攝影進行動態紀錄，並搭配全橋整流與電容儲能設計，量測不同轉速下之穩態電壓響應與平均功率。實驗結果整體趨勢與模擬預測相符，但在峰值頻率與功率大小上仍存在一定程度差異，顯示模型雖可捕捉主要動態行為，仍有待進一步修正以提升準確性。另觀察到高轉速下，因慣性力影響導致壓電樑等效剛性增加，進而產生自然頻率偏移。此外，激發訊號中亦出現奇數倍頻分量，顯示實際偏心擺之擺盪行為與理論假設（對稱、單一頻率激發）有所出入，進而影響模態激發結果。
本研究亦探討模態分離設計策略，發現透過調整內外側樑之剛性與質量比例，可提升模態響應分離度與功率平衡表現。整體而言，本研究成功建立結合理論、數值與實驗之完整分析流程，並證實雙模態升頻磁力激發系統具備於低速旋轉環境中擷取機械能並轉換為穩定電能之可行性，具潛力應用於離岸風場感測節點與其他分散式能源系統中。

This study develops a two-degree-of-freedom (2DOF) piezoelectric energy harvester for low-speed rotating systems (<3.5 Hz), like offshore wind turbines, using non-contact magnetic frequency-up conversion to enhance broadband response and power output. The system integrates a folded cantilever beam with an eccentric pendulum, employing macro-fiber composite (MFC) materials. A dynamic model was derived via energy methods, using a point-dipole magnetic model and Fourier cosine expansion for power prediction. By using numerical simulations (MATLAB, Simulink), the dynamic behaviors were analyzed at 100–200 rpm, with experiments simulating low-speed conditions to measure voltage and power. Results show consistent voltage and power trends with simulations, though inertial effects and asymmetric pendulum motion caused deviations. The methodology combines theoretical modeling, simulation, and experimental validation. Future work includes optimizing models and circuits for enhanced efficiency and stability in distributed energy systems.

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