具可調頻功能之微型壓電能量擷取器真空封裝設計開發

A Vacuum Package Design with Frequency Tuning Mechanism for Micro Piezoelectric Energy Harvesters

柯冠宇(Guan-Yu Ke)

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/NTU202100642

摘要

隨著物聯網（Internet of Things, IoT）的來臨，越來越多智慧裝置充斥在我們日常生活中。然而隨著IoT裝置數量呈現爆炸式的成長趨勢，能源的消耗是一個嚴重的議題。傳統上我們一般使用電池作為裝置之能量來源，但傳統電池得回收對環境造成不小的環境汙染影響。近年隨著微機電技術的發展，致力於尋找能夠有效代替傳統電池的使用。
在我們生活環境中，環境振動源充斥在我們日常使用的儀器，本研究中分析振動源的組成以設計元件及封裝。使用氣膠沉積設備及微機電製程，製作微型壓電能量擷取器。利用滑軌機構使元件能調整懸臂梁之有效長度，藉此調整共振頻率以擷取最大能量，並將其真空封裝，真空環境下更加提升元件之輸出表現，最後安裝在實際振動源中擷取能量。
實驗結果顯示，將元件懸臂梁之有效長度調整至9.79 mm，共振頻率為102.9 Hz，雖然振動頻率未達共振頻率，但仍擁有一定的輸出表現，輸出電壓為1.45 V，輸出功率為1.10 μW。將其完成真空封裝後安裝在風扇上，元件輸出功率為輸出電壓為1.70 V輸出功率為1.51 μW。

關鍵字

微型壓電能量擷取器 ； 共振頻率調整 ； 真空封裝 ； 壓電材料 ； 氣膠沉積法

並列摘要

With the booming of Internet of Things (IoTs) devices, there are more and more smart devices implemented into our daily life. However, the more ended devices implemented also imply the need of the power solution became much severe. Traditionally, the button batteries are the easiest power solution for remote devices. However, this solution would directly cause the amount of battery replacement and charging inconvenience. Fortunately, the power consumption of electronic devices is decreasing continuously with the improvement of semi-conductor process technique.
The ambient vibration sources are easily accessible. In this study, the vibration frequency and acceleration level from each machine should be measured and analyzed for later design. Micro piezoelectric energy harvester (MPEH) is fabricated by aerosol deposition equipment and microelectromechanical systems. With rail-like trough mechanism, effective beam length can be adjusted to change resonant frequency of MPEH. The output power of vacuum packaged device is further improved.
In this study, package is set up on fan which provides acceleration level of 0.21g. When the length of cantilever beam is adjusted to 9.79 mm, the resonant frequency is 102.9 Hz. Although vibration frequency doesn’t reach resonant frequency of MPEH, the output voltage and output power still have considerable value. The MPEH generates the output voltage of 1.45 V and max output power of 1.10 µW. With vacuum package process, the output performance of MPEH is further improved. The MPEH generates the output voltage of 1.70 V and max output power of 1.51 µW.

並列關鍵字

micro piezoelectric energy harvester ； frequency tuning ； vacuum package ； piezoelectric material ； aerosol deposition method

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