复合压电水平悬臂梁振动俘能特性试验及机电耦合模型研究  

Experimental and modelling studies on mechanical-electric energy conversion of a horizontal composite piezoelectric cantilever

作　　者：薛晓敏[1] 马强力 王佳佳 XUE Xiaomin;MA Qiangli;WANG Jiajia(School of Human Settlements and Civil Engnineering,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]西安交通大学人居环境与建筑工程学院,西安710049

出　　处：《振动与冲击》2022年第24期167-175,共9页Journal of Vibration and Shock

基　　金：国家自然科学基金(11502188)。

摘　　要：压电悬臂梁具有较好的振动俘能特性,然而其复杂力电特性及模型相关研究的不充分性导致实际应用受到制约。鉴于此,开展复合压电水平悬臂梁振动俘能特性试验及模型研究:首先,基于电路和结构基础设计搭建压电悬臂梁振动能量转换电能的试验系统,试验结果显示,压电悬臂梁俘能系统能量转换能力受外部激励频率、内部电路负载以及结构设计配重等条件的影响,其机电转换特性复杂,电压/电流-应变关系曲线呈近似椭圆形,功率-应变关系曲线呈近似蝴蝶形,还观测到由于结构自身及其配重的重力效应导致特性曲线形状呈现偏置现象;然后,提出力电耦合数学模型用于复合压电水平悬臂梁系统俘能的力电特性描述,通过与试验数据比较,验证该模型不但可以精确预测振动回收的电能(功率),还可有效模拟电压/电流-应变和功率-应变的复杂力电特性,且对试验特性曲线存在的偏置现象也能较好的模拟。试验和模型研究成果将对压电悬臂俘能系统在工程领域的进一步应用提供必要的理论基础。A piezoelectric cantilever beam harvester is the most popular type due to its simple structure and easy installation.However it is figured out to collect very low electric power resulting in very limited potential applications.In view of this,we carry out a series of studies on mechanical-electric energy conversion of a laminated composited piezoelectricy(PZT)cantilever in terms of characteristic experiment and modeling.We set up the experiment of energy conversion based on a circuit and structural design.The test data reveal the harvesting capability significantly affected by three factors that are external excitation,internal resistance load and tip mass.The test data also reveal the mechanical-electric relationship of the harvester demonstrating complicated characteristics,in which voltage/current-strain curves are oval-shaped and power-strain curves are butterfly-shaped.Furthermore,those curves demonstrate bias and even more obvious while tip mass gains more weight,which should attribute to gravity effect of the horizontal cantilever harvester.On the basis,a coupled electromechanical model was proposed by taking gravity effect in consideration to simulate the aforementioned electromechanical behavior of the cantilever harvester.Through comparison with the test data,the model was verified that it can not only precisely predict the harvested electric power,but also effectively describe complex characteristic and its bias deterioration aroused by gravity effect.Overall,the studies have an in-depth exploration of vibration-based energy conversion of PZT harvester.It is believed to have a promising application prospect in this kind of PZT harvesters.

关 键 词：振动能量收集 复合压电悬臂水平梁 力电耦合建模 重力效应 特性曲线偏置 

分 类 号：TN384[电子电信—物理电子学] O343[理学—固体力学]