旋磁激励式预弯梁压电俘能器建模仿真与试验  

Prebending-cantilever Piezo-harvester Excited by Rotary Magnet

作　　者：王淑云[1] 朱雅娜[1] 阚君武[1] 富佳伟 张忠华[1] 张肖逸 WANG Shuyun;ZHU Yana;KAN Junwu;FU Jiawei;ZHANG Zhonghua;ZHANG Xiaoyi(Institute of Precision Machinery and Intelligent Structure,Zhejiang Normal University,Jinhua 321004;MicroPort UroCare Medical Technology(Jiaxing)Co.,Ltd.,Jiaxing 314000;Zhejiang Dafeng Industry Co.,Ltd.,Hangzhou 310000)

机构地区：[1]浙江师范大学精密机械与智能结构研究所,金华321004 [2]微创优通医疗科技(嘉兴)有限公司,嘉兴314000 [3]浙江大丰舞台设计有限公司,杭州310000

出　　处：《机械工程学报》2020年第14期224-230,共7页Journal of Mechanical Engineering

基　　金：国家自然科学基金(51877199,61574128,51577173,51377147);浙江省自然科学基金(LY17F010004,LY16F010003)资助项目。

摘　　要：针对现有旋转式压电俘能器存在的问题以及旋转机械监测系统的自供电需求,提出一种旋磁激励式预弯梁压电俘能器。建立了俘能器动态响应模型,通过数值仿真和试验方法获得了转速、磁铁数量比、压缩比及负载电阻对其输出性能的影响规律。结果表明,磁铁数量比对激振力作用形式、最佳转速、谐振峰数及输出电压(振幅放大比)均有影响;激振力形式随磁铁数量比增大由脉冲激励逐渐变为正偏置的三角波激励;随着磁铁数量比的增加,谐振峰数量及最佳转速减小,存在最佳磁铁数量比使得输出电压(振幅放大比)最大;压电振子预弯装配后俘能器可实现等应变发电,适当增大压电振子的压缩比可降低俘能器轴向刚度提高俘能器在低转速域内的输出能力,最佳转速随压缩比的增加而减小,且相邻谐振峰的间距随着压缩比的增加而减小。压缩比为0.17时的最大输出电压是压缩比为0.02时的1.5倍;当磁铁数量比为0.26,压缩比为0.08,转速为448r/min时输出功率可达1.55mW。To reduce the problems of existing rotary piezoelectric energy harvester and meet the demands of the rotating mechanical monitoring system for self-powered,a prebending-cantilever piezo-harvester(PCPH)excited by rotary magnet is presented.To obtain the influence of magnet ratio,compression ratio,and rotating speed on the output performance,a dynamic response model for the PCPH is established and simulated.The analytical results show that the number of the magnet has effect on the optimal speed,the number of resonant peaks,the peak voltage and the exciting force.With the increase of the magnet ratio,the number of resonant peaks and the optimal speed decrease,there is optimum magnet ratio to achieve the maximum of peak voltage and the amplitude ratio;The form of the exciting force is changed from the pulse excitation to the simple harmonic excitation and then to the forward biased harmonic excitation along with the increasing magnet ratio.The PCPH can achieve equal strain power generation using piezoelectric vibrator pre-bending assembly.Appropriate increase of the compression ratio can reduce the axial stiffness of the PCPH to improve its capacity in the low rotating speed.The maximum peak voltage of the compression ratio of 0.17 is 1.5 times that of the compression ratio of 0.02;when magnet ratio is 0.26,compression ratio is 0.08,rotating speed is 448 r/min,and the output power is up to 1.55 mW.

关 键 词：旋磁激励 预弯梁 压电俘能器 

分 类 号：TN384[电子电信—物理电子学] TM619[电气工程—电力系统及自动化]