振動獵能器為透過換能器將結構振動能量轉換為電能之綠色能源系統，為近年振動及能源領域之熱門研究主題。傳統的振動獵能系統因採用線性系統進行設計，因此僅有在操作於系統的自然頻率時才可發揮獵能效能。為了增廣獵能頻寬，過去已有許多研究使用非線性系統進行獵能器開發。然而，由於非線性系統具有多個穩態振動週期解，現有的非線性獵能器僅有在受到向上掃頻(frequency sweep-up)的激振條件時可發揮良好的發電效益，當系統受到向下掃頻激振時，獵能器的系統動態將收斂至振幅較小的週期解而使有效頻寬大幅縮小，因而降低非線性獵能器的實務應用價值。為了使振動獵能系統於各種掃頻條件下皆可保有增廣的獵能頻寬，本論文提出一種新型的非線性振動獵能系統，此新設計能使獵能器於向下掃頻(frequency sweep-down)時觸發非線性跳躍現象，並強迫系統動態收斂至大振幅的非線性週期解，使非線性振動獵能器能同時適應向上掃頻及向下掃頻的激振環境。本研究對此新型非線性振動獵能器進行數值模擬和實驗驗證，並提供振動獵能器的參數設計指南。

Vibration energy harvesters are green energy systems that convert structural vibration energy into electrical energy through transducers. It has become a hot research topic in the field of vibration and energy in recent years. Traditional vibration energy harvesting systems are designed with a linear system, so energy harvest performance can only be achieved when operating at the natural frequency of the system. In order to extend the energy harvesting bandwidth, there have been many studies in the past using nonlinear systems for the development of energy harvesting devices. However, since the nonlinear system has more than one stable attractors, the existing nonlinear energy harvesters can only exert good power generation efficiency when they are subjected to up-sweep excitation conditions. When the system is subjected to down-sweep excitation conditions, the system dynamics of the energy harvesting device will converge to an attractor with a smaller amplitude, which will greatly reduce the effective bandwidth, thus reducing the practical application value of the nonlinear energy harvesting device. In order to make the vibration energy harvesting system maintain an extended energy harvesting bandwidth under various frequency sweep conditions, this paper proposes a new type of nonlinear vibration energy harvesting system. This new design enables the broadband energy harvesting in both the up-sweep and down-sweep excitation conditions by using a trigger mechanism that forces the system to jump to the large-amplitude vibration at a specific excitation frequency. In this study, the numerical simulation and experimental verification of this new nonlinear vibration energy harvesting device are carried out, and the parameter design guideline of the vibration energy harvesting device is provided.

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