Acoustic holograms in contactless ultrasonic power transfer systems: Modeling and experiment
Acoustic holograms in contactless ultrasonic power transfer systems: Modeling and experiment
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DOI：
10.1063/1.5048601
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发表时间：
2018-12
影响因子：
3.2
通讯作者：
Marjan Bakhtiari-Nejad;A. Elnahhas;M. Hajj;S. Shahab
中科院分区：
文献类型：
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作者：
Marjan Bakhtiari-Nejad;A. Elnahhas;M. Hajj;S. Shahab
非接触式超声波声波能量转移(UAET)是一种新技术，它消除了与需要定期更换的有线电气连接或电池相关的风险或不切实际之处。这项技术基于压电接收器接收超声波频率的声波，可以用来对低功率电子产品进行无线充电。这项技术的实施和效率可以通过对空间中传输的声能进行图案化和聚焦来同时为分布式传感器或设备供电来显著提高。这项工作研究了使用声全息图在目标接收器位于特定焦点或区域的平面上创建多焦点压力图案。首先，利用迭代角谱方法设计了相移全息图。然后，结合全息图，建立了用于为多个压电接收器供电的轴向振动圆柱形发射机的多物理声电弹性模型。还进行了实验，以展示声全息图选择性地为接收器阵列供电的能力。分析和实验结果都表明，暴露在全息图产生的多焦点压力图案下的接收器的功率传输显著增强。作为一个案例研究，研究了一个接收器为目标的双焦点接收器设置。UAET仿真预测到目标接收器的功率传输将增加一倍，并通过概念验证实验进行了验证。文中还报道了系统参数如输入频率和全息孔径大小的影响。
Contactless ultrasonic acoustic energy transfer (UAET) is a new technology that eliminates risks or impracticalities associated with wired electrical connections or batteries that need to be replaced on a regular basis. This technology, which is based on the reception of acoustic waves at ultrasonic frequencies by piezoelectric receivers, can be used to wirelessly charge low-power electronics. The execution and efficiency of this technology can be significantly enhanced through patterning and focusing of the transmitted acoustic energy in space to simultaneously power distributed sensors or devices. This work investigates the use of an acoustic hologram to create a multifocal pressure pattern in a plane where target receivers are located at specific focal points or regions. First, a phase-shifting hologram is designed using an iterative angular spectrum approach. Then, a multi-physics acoustic-electro-elastic model is presented for an axially vibrating cylindrical transmitter used to power multiple piezoelectric receivers, in conjunction with the hologram. Experiments are also performed to show the capability of an acoustic hologram to selectively power an array of the receivers. Both analytical and experimental results show a dramatic enhancement of power transfer to receivers exposed to a multi-focal pressure pattern created by the hologram. As a case study, a bi-focal receiver setup is investigated where one receiver is targeted. The UAET simulation predicts a doubling of the power transfer to the targeted receiver, which is verified by the proof-of-concept experiment. The effects of system parameters such as input frequency and hologram aperture size are also reported.