應用於低轉速旋轉環境中之微型壓電能量擷取器

A miniatured piezoelectric energy harvester applied in a low-speed rotational environment

劉家亘(Chia-Hsuan Liu)

指導教授 ： 吳文中

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202101856

摘要

在本研究中，透過金屬微機電製程及氣膠沉積技術，製作出應用於低轉速之旋轉環境的微型壓電能量擷取器。在理論模型部分，則是採用透過旋轉過程中所產生的離心力，改變壓電元件的勁度大小，來達到被動調頻的效果。而在實驗部分，則包含了垂直震盪與旋轉環境兩部分，首先透過垂直震盪方式將壓電元件操作在其共振頻上並量測輸出，此目的為為之後將引入離心力的旋轉環境實驗建立出模型，而在旋轉環境實驗部分，可以預先透過MATLAB軟體來預測共振頻可能的位置，接著進行手動掃頻、找出最佳阻抗、量測元件在不同轉速下之輸出，並探討不同架設方式下的輸出結果。最後則是將此實驗與日常生活相結合，將在日常生活中通勤情況下的速度變化透過腳踏車測速器記錄下來，將之轉換成轉速，輸入至實驗用旋轉平台，來模擬在真實情況下所能擷取到的能量。

關鍵字

壓電能量擷取器 ； 氣膠沉積製程 ； 旋轉環境 ； 離心力

並列摘要

In this research, through the metal micro-electromechanical process and aerosol deposition technology, a miniature piezoelectric energy harvester (PEH) used in a low-speed rotating environment was fabricated. In the theoretical model section, the centrifugal force generated during the rotation is used to change the stiffness of the piezoelectric device to achieve the effect of passive tuning in order to adapt to the environment. In the experimental section, it includes two parts which are vertical oscillation and rotational excitation. First, the PEH was operated at its resonant frequency under the vertical oscillation and the output power was measured. This was done for the subsequent rotating environment experiment where the centrifugal force was considered. In the rotational excitation section, MATLAB software was used to predict the possible value of the resonant frequency in advance. Afterwards, the frequency sweep was conducted manually, then the optimum load impedance was found, the power output of the PEH at different speeds was measured, and results under different mounting methods were discussed. Finally, the experiment was applied to daily life where the speed under commuting time was recorded through a speed sensor, then converted to frequency, and then imported into the experiment's rotating platform to simulate the energy that can be harvested under the real environment.

並列關鍵字

Piezoelectric energy harvester ； aerosol deposition ； rotational environment ； centrifugal force

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