基于多模态扩频理论的压电振动能量采集系统

Piezoelectric Vibration-Energy Acquisition System Based on Multimodal-Spread-Spectrum Theory

以同时提升多模态采集和增加带宽为研究方向,结合多模态扩频理论,建立了一套多模态宽频且能多方向工作的压电振动能量采集系统。该系统包含能量采集器和电源管理电路两个模块。其中,采集器包括4种谐振频率,组成了较宽的工作频带,保证了该采集器在低频振动工作环境下高效率地收集振动能量;电源管理电路将采集到的交流电转换为稳定的直流电,再对电容或电池等储能元件充电以供微电子器件使用。经过模态和谐响应分析后,搭建了实验平台并对采集系统进行实验测试。实验结果表明,在加速度6 m/s^(2)简谐力激励下,工作频带为16.1~27.8 Hz,输出电压最高可达35.75 V,阻抗匹配后最优阻值为200 kΩ,此时输出功率为115.85μW。

In this study,multimodal acquisition and bandwidth broadening are enhanced by employing multimodal spread spectrum theory to establish a versatile piezoelectric vibration-energy acquisition system.The system comprises two modules-an energy collector and a power-management circuit.The collector operates across four resonant frequencies,thus ensuring efficient energy harvesting in low-frequency vibration settings.The power-management circuit converts AC power into stable DC power for charging energy-storage components.Following modalharmony response analysis,an experimental platform is constructed for system testing.Experimental results indicate an operational frequency band of 16.1 to 27.8 Hz,with a peak output voltage of 33.75 V under a simple harmonic force and an acceleration of 6 m/s2.Upon impedance matching,the optimal resistance value is shown to be 200 kΩ,which results in an output power of 115.85μW.