基于驰振的压电能量采集器建模与实验研究

Modeling and Experimental Study of Galloping-Based Piezoelectric Energy Harvester

在压电能量采集器分布参数模型的基础上,对驰振作用下悬臂式压电能量采集器的振动和能量采集情况作进一步理论分析,得到质量块起振风速以及从起振到驰振过程中所采集到功率的解析解。利用直流式闭口低速风洞分别对正三棱柱、正四棱柱悬臂式压电能量采集器进行实验测试,结果表明,正四棱柱能量采集器和正三棱柱能量采集器的采集功率分别达到0.248 5mW和0.125 9mW。通过对采集功率和电压时程曲线进行对比,其理论解和实验值吻合程度较高,理论模型具有较高精度。通过理论模型分析发现:风速越大,质量块质量越小,能量采集器采集功率越高;对于不同条件下的能量采集器均存在最优外载阻值,低风速下还会出现双最优外载阻值。

Based on the distributed parameter model of piezoelectric energy harvester,the vibration and power of cantilever piezoelectric energy harvester under galloping are further theoretically analyzed,meanwhile the analytical solution of tip′s onset speed and harvested power from onset to galloping are obtained in this paper.The cantilever piezoelectric energy harvesters with a regular tri-prism tip and a regular quadprism tip are tested in a closed direct-flow low-speed wind tunnel.The experimental results show that their harvested power reaches 0.1259 mW and 0.2485 mW,respectively.Comparing the harvested power and its history curve,it is found that the theoretical solutions are in good agreement with the experimental ones,showing a high accuracy of the theoretical model.Thought the theoretical model analysis,the larger the wind speed and the smaller the tips mass are,the higher the power of energyharvester will be.For the energy harvester at different conditions,there are optimal external load resistance values,and there are also two optimal external load resistance values at low wind speed.