The piezoelectric energy harvesters can be an integral part of self-powered sensor system due to its compatibility with semiconductor technology. In this paper, a modified structural geometry has been proposed in order to improve the performance of energy harvesters with classical cantilever topology by incorporating through holes. A detail mathematical analysis has been carried out to manifest the effect of through hole on resonant frequency of piezo harvester using Rayleigh–Ritz method. The theoretical analysis is validated through simulation studies as well as experimental results. Accordingly, an in-house low cost experimental set-up has been developed using Polyvinylidinefluoride (PVDF) based macro-level energy harvester and loud speaker based vibration set-up. It has been observed that the resonant frequency is reduced from 26.23 Hz to 21.94 Hz due to incorporation of hole to classical cantilever for a given dimension. With input acceleration of 3.7 g, the developed macro-harvester set-up resonates at 23 Hz and is capable of producing power of 59.93 $$\mu$$ μ W with hole based structure whereas power of 14.60 $$\mu$$ μ W is obtained in case of without hole based structure. The macro-scale energy harvester with modified geometry has been also designed and simulated in finite element analysis method to validate the mathematical analysis and it is found that lower the resonant frequency higher the power obtained with the hole based topology. It is verified from the experimental, simulation and theoretical studies, that there is a dominant effect of through hole in the performance improvement of piezoelectric energy harvester.

中文翻译：

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结合内部实验装置的孔的低频压电能量收集器的性能改进

由于与半导体技术兼容，压电能量收集器可以成为自供电传感器系统的一个组成部分。在本文中，提出了一种改进的结构几何形状，以通过引入通孔来提高具有经典悬臂拓扑结构的能量收集器的性能。使用Rayleigh-Ritz方法进行了详细的数学分析，以证明通孔对压电采集器谐振频率的影响。通过模拟研究和实验结果验证了理论分析。因此，使用基于聚偏氟乙烯 (PVDF) 的宏观能量收集器和基于扬声器的振动装置开发了内部低成本实验装置。据观察，谐振频率从 26.23 Hz 降低到 21 Hz。94 Hz 由于在给定尺寸下将孔与经典悬臂结合。输入加速度为 3.7 g，开发的宏收集器设置在 23 Hz 共振，能够产生 59.93 $$\mu$$ μ W 的功率，具有基于孔的结构，而功率为 14.60 $$\mu$$ μ W 是在没有基于孔的结构的情况下获得的。还通过有限元分析方法设计和模拟了具有修改几何形状的宏观能量收集器，以验证数学分析，发现谐振频率越低，孔基拓扑获得的功率越高。实验、仿真和理论研究均验证了通孔对压电能量采集器性能提升的主导作用。