Liu Huifang, Cong Chen, Zhao Qiang, Ma Kai
School of Mechanical Engineering, Shenyang University of Technology, Shenyang 110870, China.
Sensors (Basel). 2019 Aug 3;19(15):3412. doi: 10.3390/s19153412.
Vibration energy harvesting attempts to generate electricity through recycling the discarded vibration energy that is usually lost or dissipated, and represents an alternative to traditional batteries and may even lead to reliable self-powered autonomous electronic devices. Energy harvesting based on magnetostrictive materials, which takes advantage of the coupling characteristics of the Villari effect and the Faraday electromagnetic induction effect, is a recent research field of great interest. Aiming to develop a new type of magnetostrictive energy harvester using Fe-Ga alloy, which is suitable for harvesting the vibration energy from base excitations and free excitations, a Fe-Ga based cantilever harvester was proposed. The energy harvesting performance of the harvester prototype, including its resonance characteristics, open-circuit output voltage-frequency response and amplitude characteristic under base excitation, influence of external resistance, energy harvesting performance under free excitation, the function of pre-magnetization and so on was studied systematically and carefully by experiments. In terms of the volume power density, the harvester prototype without pre-magnetized magnet when in series with the optimal resistor load displays a value of 2.653 mW/cm. The average conversion efficiency without a pre-magnetic field is about 17.7% when it is in series with a 200 resistance. The energy harvesting and converting capability can therefore be improved greatly once the Fe-Ga beam is highly pre-magnetized. The prototype successfully lit up multi-LEDs and digital display tubes, which validates the sustainable power generation capacity of the fabricated prototype.
振动能量收集试图通过回收通常会损失或耗散的废弃振动能量来发电，是传统电池的一种替代方案，甚至可能催生可靠的自供电自主电子设备。基于磁致伸缩材料的能量收集利用了维拉里效应和法拉第电磁感应效应的耦合特性，是一个近期备受关注的研究领域。旨在开发一种适用于收集基础激励和自由激励振动能量的新型铁镓合金磁致伸缩能量收集器，提出了一种基于铁镓的悬臂式收集器。通过实验系统且仔细地研究了收集器原型的能量收集性能，包括其共振特性、基础激励下的开路输出电压 - 频率响应和幅度特性、外部电阻的影响、自由激励下的能量收集性能、预磁化的作用等。在体积功率密度方面，未预磁化磁体的收集器原型与最佳电阻负载串联时显示的值为2.653 mW/cm³。当与200Ω电阻串联时，无预磁场时的平均转换效率约为17.7%。因此，一旦铁镓梁被高度预磁化，能量收集和转换能力可大幅提高。该原型成功点亮了多个发光二极管和数码显示管，验证了所制造原型的可持续发电能力。
