隨著物聯網與可攜式電子設備日益普及，對於低功耗、自供能系統的需求日漸增加。本研究旨在開發一種具備升頻轉換機制的壓電式能量獵取裝置，透過磁吸碰撞與滑動結構實現低頻激發下的高頻輸出，以提升能量轉換效率。在分析方法上，本研究採用懸臂樑變形理論與拉格朗日方法推導多自由度與單自由度動態模型，考慮壓電耦合效應與磁力非線性影響；並進行能量法速度推導與等效參數估算，建立理論模型。實驗方法則包含實體原型製作、磁場與彈簧常數量測、壓電耦合係數與阻尼比量測，並透過高速攝影與示波器進行動態響應記錄與電壓分析。研究結果顯示本裝置可透過單次低頻激發產生連續高頻振動，成功延長振動持續時間並提升壓電輸出效率。多自由度模型與實驗結果相符，誤差低於10%，驗證了模型準確性。此外，透過參數優化，本系統於最佳阻抗與結構配置下可達到最大電壓輸出與功率轉換。整體而言，本研究提出之機構具備低頻啟動、高頻響應與模組化調整等優勢，具實際應用潛力，未來可進一步朝向多模組整合與自供電感測器應用發展。

With the rapid growth of the Internet of Things (IoT) and portable electronics, the demand for low-power self-sustaining systems such as energy harvester devices is increasing. This study presents a piezoelectric energy harvester with a frequency up-conversion mechanism, which utilizes magnetic attraction, impact, and sliding structures to achieve high-frequency output under low-frequency excitation, thereby improving energy conversion efficiency. A theoretical framework is developed using cantilever beam deformation theory and the Lagrangian method to derive both multi-degree- and single-degree-of-freedom dynamic models, incorporating piezoelectric coupling and nonlinear magnetic effects, while the energy method and equivalent parameter estimation are employed for model formulation. Experimental investigations include prototype fabrication, measurement of magnetic fields, spring constants, piezoelectric coupling coefficients, and damping ratios, as well as dynamic response and voltage characterization via high-speed imaging and oscilloscope analysis. Results show that a single low-frequency excitation can induce sustained high-frequency vibrations, extending vibration duration and enhancing output efficiency, with the multi-degree-of-freedom model agreeing well with experimental results (error <10%). Furthermore, parameter optimization demonstrates that maximum voltage and power conversion can be achieved under optimal impedance and structural configurations. Overall, the proposed mechanism offers advantages of low-frequency activation, high-frequency response, and modular adjustability, highlighting its potential for practical applications in multi-module integration and self-powered sensing.

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