壓電與磁式智慧材料結構所建構之獵能與感測技術

Abstract

本論文中研究了三軸壓電式振動獵能器與磁力式磁感測器，元件使用了智慧材料結構來建構出機械-壓電-磁的多重耦合。針對振動獵能，當對獵能器施加X軸向(或Y軸向)平面內環境振動或Z軸向出平面環境振動時，獵能器能藉由智慧材料結構將這些振動轉換為壓電輸出。結果顯示，在任何三軸環境振動下，我們的理論公式推導、有限元素分析與實驗得到的電壓輸出皆互相匹配(此結果表明了理論公式推導與有限元素分析皆可以精準預測實驗結果)。亦即是我們的獵能器可以成功的擷取三軸環境振動能。而針對磁場感測，磁感測器使用智慧材料結構將X軸向(或Y軸向)平面內磁場與Z軸向出平面磁場轉換為壓電輸出。結果顯示，在任何三軸交流與直流磁場下，磁場測器可以產生具備相當靈敏度的相應電壓輸出。這表明了磁感測器能夠成功的感測三軸環境磁場。此外，由於磁感測器使用了具壓電效應的智慧材料結構，它也能夠擷取三軸環境振動能。總而言之，根據上述之特典與優勢，我們的獵能器與磁感測器將成為今後開發三軸獵能器與三軸交流/直流磁感測器的核心技術之一，特別是某些特定之工業應用上(例如智能車輛、流程監控、安全監控系統等等)。

In the dissertation, I study a three-axis piezoelectric-based vibrational energy harvester and a magnetic-force-based magnetic sensor, which use smart material-structures capable of conducting mechanical-piezoelectric-magnetic multiple conversion. For vibrational energy harvesting, when x-axis (or y-axis) or z-axis ambient vibrations are applied to the energy harvester, the energy harvester uses the smart material-structure with the piezoelectric effect to convert these vibrations to piezoelectric voltage outputs. Results show that under any of the three-axis vibrations, our modeled, finite-element analyzed (FEA), and experimental voltage outputs are in consist (this indicates either modeling or FEA can accurately predict experimental results). That is, our harvester can successfully harvest three-axis ambient vibrations. For magnetic-field sensing, the magnetic sensor uses the smart material-structure to convert x-axis (or y-axis) and z-axis magnetic fields to piezoelectric voltage outputs. Results show that under any of the three-axis AC and DC magnetic fields, the magnetic sensor can produce corresponding experimental voltage-outputs with decent sensitivities. This indicates the magnetic sensor is able to successfully sense three-axis magnetic fields. Moreover, due to the smart material-structure with the piezoelectric effect, the magnetic sensor is capable of harnessing three-axis ambient vibrations. In conclusion, according to above features and advantages, our energy harvester and magnetic sensor will be one of core technologies for developing three-axis energy harvesters and AC/DC magnetic sensors in the future, especially for certain industrial applications (e.g., smart vehicle-monitoring, process-monitoring, security-monitoring systems, etc).