一种回折梁结构低频压电能量采集器

A Low-frequency Piezoelectric Energy Harvester with Folded Beam Structure

为满足振动频率在一定范围内变动,且在空间有限的环境下无线传感器系统的自供能需求,设计了一种具有3个自由度的回折梁振动压电能量采集器。基于系统结构和工作原理,进行了理论分析及建立了回折梁结构有限元模型,并对该模型进行了有限元分析和模态仿真。制作回折梁压电能量采集器的原理样机,搭建试验平台,在振动台上进行试验。试验结果表明,理论分析、有限元模拟结果与实验结果吻合,在3.5~8.5 Hz低频振动下能产生大于5 V的电压,最高输出电压约为17.5 V,是传统单梁结构的1.4倍,且具有3个输出电压峰,工作带宽为传统单梁结构的4.5倍,实现了宽频效果。所提出的回折梁结构压电能量采集器在低频、振动频率变化的环境中有效且自适应。

In order to meet the self-powered requirements of wireless sensor systems with vibration frequency varying in a certain range and limited space,a three degree-of-freedom vibration beam piezoelectric energy harvester with folded beam structure is designed.Based on the system structure and working principle,the theoretical analysis was carried out,and the finite element model of the folded beam structure was established.The finite element analysis and modal simulation are carried out.A prototype of the piezoelectric energy harvester with folded beam is fabricated,and the test platform was built and tested on the vibration table.The experimental results show that the theoretical analysis and finite element simulation results are basically consistent with the experimental results.Under the low frequency vibration of 3.5~8.5 Hz,the voltage greater than 5 V can be generated,and the maximum output voltage is about 17.5 V,which is 1.4 times that of the traditional single beam structure.Furthermore,it has three output voltage peaks and the working bandwidth is 4.5 times that of the traditional single beam structure.The effect of wide frequency is realized.The proposed piezoelectric energy harvester with folded beam structure can be effectively and adaptively used in low frequency and vibration frequency changing environments.