压电悬臂梁俘能器多模态俘能效果研究  

Multi-Mode Vibration with Piezoelectric Cantilever for Energy Harvesting

作　　者：王红艳[1,2] 谢涛[1] 单小彪[1] 袁江波[1] 

机构地区：[1]哈尔滨工业大学机电工程学院,哈尔滨150001 [2]齐齐哈尔大学计算机与控制工程学院,黑龙江齐齐哈尔161006

出　　处：《西安交通大学学报》2010年第6期114-119,共6页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(50875057)

摘　　要：研究了一种带质量块的压电悬臂梁俘能器,推导得到俘能器振型函数,并进行数值计算,分析不同质量比时系统振型特点,以及系统各阶固有频率与质量比的关系.数值计算结果表明:质量比小于0.5时,对系统各阶固有频率影响较大;质量比趋于无穷大时,自由边界条件会转化为夹持边界条件;俘能器二阶及二阶以上模态时在梁长度方向上存在应变节点,节点两侧应变符号相反.为提高俘能效率,避免压电晶片电极上电荷抵消现象的发生,可在悬臂梁上应变节点两侧分段粘贴压电晶片,提取多个谐振频率时的振动能,实验结果表明分段电极法可以产生更多的电能.Piezoelectric cantilever energy harvester with seismic mass is investigated.The vibration mode function is deduced,and the numerical calculation reveals the vibration mode characteristics with different mass ratio and the effects of mass ratio on the structure natural frequency.It is demonstrated that the mass ratio M^0 remarkably reduces the structure natural frequencies in the range of M^00.5,and infinite M^0 leads to a clamp end boundary condition.Vibration modes of a cantilevered piezoelectric energy harvester other than the fundamental mode have certain strain nodes where the dynamic strain distribution changes sign in the longitudinal direction of beam.Covering the strain nodes of the vibration modes with continuous electrodes results in strong cancellations of the electrical outputs,and energy harvesting efficiency is declined.And how to avoid the cancellation in energy harvesting by segmented electrode pairs is discussed.The experiment results show that segmented electrodes facilitate generating higher energy.

关 键 词：压电俘能器 悬臂梁 分段电极 应变节点 

分 类 号：TN384[电子电信—物理电子学] TP211[自动化与计算机技术—检测技术与自动化装置]