Performance of Energy Harvester Using Iron–Gallium Alloy in Free Vibration
Performance of Energy Harvester Using Iron–Gallium Alloy in Free Vibration
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DOI：
10.1109/tmag.2011.2158303
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发表时间：
2011-09
影响因子：
2.1
通讯作者：
Toshiyuki Ueno;Sotoshi Yamada
中科院分区：
文献类型：
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作者：
Toshiyuki Ueno;Sotoshi Yamada
我们提出了一种微型能量收集装置，使用铁镓合金（Galfenol），能够从环境振动中产生电能。Galfenol是一种韧性磁致伸缩材料，具有高压磁常数、良好的机械加工性和大的逆磁致伸缩效应，通过该逆磁致伸缩效应，磁化可以通过机械应力而变化。该装置由两束Galfenol与铁轭、线圈和偏置磁体组合而成。施加在悬臂梁尖端的弯曲力在一个梁中产生由拉伸应力引起的通量增加，而在另一个梁中产生由压缩引起的通量减少。通量的时间变化在缠绕线圈上产生电压。这种能量采集器在尺寸和效率方面优于传统类型的设备，例如使用压电材料的设备，并且它具有高鲁棒性和低电阻抗。此外，该结构只需要很低的机械力就能发电。本文对有效蓄能的自振特性进行了研究。从实验结果来看，振动中的能量转换效率与谐振频率成正比。
We propose a micro energy-harvesting device, using an iron-gallium alloy (Galfenol), capable of generating electrical energy from ambient vibrations. Galfenol is a ductile magnetostrictive material with a high piezomagnetic constant, good machinability, and a large inverse magnetostrictive effect by which magnetization can be varied by mechanical stress. The device consists of two beams of Galfenol combined with iron yokes, coils, and a bias magnet. A bending force applied at the tip of the cantilever yields a flux increase by tensile stress in one beam, and a flux decreases in the other by compression. The time variation of the flux generates a voltage on the wound coils. This energy harvester has advantages over conventional types of device, such as those using piezoelectric materials, with respect to size, and efficiency, and it has high robustness and low electrical impedance. In addition, the structure needs only a low mechanical force to generate electricity. In this paper, the free vibration characteristic to accrue electric energy effectively is examined. From the experimental results, the energy conversion efficiency in the vibration is inverse proportional to the resonant frequency.