三稳态压电振动能量采集器的动力学建模、仿真与实验研究

Dynamic Modeling,Simulation and Experiment Validation of a Tri-Stable Piezoelectric Vibration Energy Harvester

为探究磁-机-压电耦合型三稳态压电能量采集器的非线性动力学行为,利用磁偶极子点荷方法计算得到了能量采集器末端受到的非线性磁力,基于欧拉-伯努利梁理论和拉格朗日方程建立了三稳态压电振动能量采集器的分布参数机电耦合动力学模型,仿真分析了系统参数(d、dg)对能量采集器的势能、磁力以及非线性动力学输出特性的影响。研制了磁-机-压电耦合型三稳态振动能量采集器原理样机,搭建了样机实验平台,实验验证了理论模型与仿真结果的正确性。研究结果表明:适当调整d和dg可使压电振动能量采集器分别作单稳态、双稳态和三稳态运动,其中三稳态运动存在3个势能阱,势能阱的深度和宽度均小于双稳态压电振动能量采集器的势能阱深度和宽度,这有利于提升振动能量采集器的工作频带和采集输出效率。

In order to explore the nonlinear dynamic behaviors of a tri-stable piezoelectric vibration energy harvester(TPVEH)with magnetic-mechanical-piezoelectric coupling. The magnetic dipole model is used to establish the nonlinear potential energy and magnetic force model of the TPVEH. Based on this model,the distributed parameter electromechanical coupling dynamic model of the TPVEH is established by using Euler-Bernoulli beam theory and Lagrange equation. Then the dynamic model is used to simulate and analyze the influences of the parameters on the potential energy,magnetic force and nonlinear dynamic output characteristics of the TPVEH. Subsequently,a prototype of the TPVEH is developed,and an experimental platform is setup to test and validate the results obtained from the theoretical model. The research results show that there are three potential wells in the TPVEH. The depth and width of the potential wells are less than those of the bi-stable piezoelectric vibration energy harvester(BPVEH). This is helpful to expand the working frequency band and improve the output efficiency of the TPVEH.