A piezoelectric cantilever with novel large mass for harvesting energy from low frequency vibrations

Lu Wang,Chen Jia,Yumeng Wu,Yulong Zhao,Xiangyang Zhou,Zhuangde Jiang,Dejiang Lu,Libo Zhao

doi:10.1063/1.5044558

Lu Wang, Chen Jia + Show 6 more

Open Access

https://doi.org/10.1063/1.5044558

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Journal: AIP Advances	Publication Date: Nov 1, 2018
Citations: 11	License type: cc-by

Affiliation: Xi'an Jiaotong University, Beihang University

Abstract

The piezoelectric cantilever with a large proof mass is a classic vibration energy harvesting structure. In this study, in order to harvest much more energy from low frequency vibration in the finite volume, a novel L type mass block is proposed and compared with a traditional rectangular mass block for the piezoelectric cantilever. A theoretical modeling of lumped parameter system is carried out considering the effect of mass block length on mass, stiffness and damping. A series of PZT bimorph cantilevers with brass proof mass prototypes are fabricated for the experimental verification. Their eigenfrequency and maximum piezoelectric power output are analyzed by the experiment and simulation. The piezoelectric cantilever with L type mass block avoids the weakness of decreasing the effective length of piezoelectric cantilever, and has lower eigenfrequency and larger piezoelectric power output than that with rectangular mass block. Its piezoelectric power output of 192 mW/(g2) can be obtained at the low resonant frequency of 18.1 Hz and the optimal load impedance of 5kΩ, and the unit volume power density is as high as 24.6 mW/(cm3×g2).

Highlights

With the rapid development of the internet of things (IoT), the problems of limited energy supply for electronic devices such as wireless sensors are urgently to be solved
The piezoelectric vibration energy harvesting is realized with the piezoelectric effect of the piezoelectric materials.[4]
According to the related reports,[8,9,10,11,12,13] the resonant frequency of the piezoelectric vibration energy harvester (PVEH) with traditional rectangular mass block is generally above 50 Hz, which is unsuitable for low frequency ambient vibration energy harvesting

Summary

INTRODUCTION

With the rapid development of the internet of things (IoT), the problems of limited energy supply for electronic devices such as wireless sensors are urgently to be solved. A large mass by much increases the lm will reduce the effective length of the piezoelectric cantilever, which will increase resonant frequency[7] and necessarily reduce the length (L- lm) of the highly deformed beam portion, which thereby will reduce the energy harvesting capabilities of the device. According to the related reports,[8,9,10,11,12,13] the resonant frequency of the PVEH with traditional rectangular mass block is generally above 50 Hz, which is unsuitable for low frequency ambient vibration energy harvesting. Without reducing the length of the piezoelectric cantilever, the PVEH of this structure increases the proof mass and has low resonant frequency and high power output

THEORETICAL ANALYSIS

CONTRAST

APPLICATION

CONCLUSION