基于惯性旋转结构的低频振动能量采集器研究

Research on Energy Harvester for Low Frequency Vibration Based on Inertial Rotary Structure

对周围环境一些常见振动源进行采样与频谱分析,结果表明,低频振动源分布广泛且通常具有较大的振动加速度,是振动能量采集的理想来源。针对低频振动源,提出一种基于惯性旋转结构的能量采集器,可以将直线运动转换为高速惯性旋转运动,并对其工作原理与动力学模型进行详细分析。试验结果表明,该能量采集器可以从成年人的一次踩踏中收集到85.2 mJ能量,瞬时输出功率最高可达32.2 mW。通过持续收集人体行走产生的能量,该能量采集器能够成功驱动一个无线传感健康监测系统正常工作。此外,通过优化器件的尺寸及结构,该能量采集器还可以被用于采集海洋波浪能量,其平均输出功率可达112.2 mW,功率密度为58.87μW/cm~3,并探究了器件结构参数、外界激励条件等因素对输出的影响。

Some common vibration sources in our ambient environment are sampled and their spectrum are analyzed.The results show that low-frequency vibration sources are widely distributed and typically have large vibration acceleration,which means they are an ideal energy source for vibration energy harvesting.For low-frequency vibration sources,an energy harvester based on an inertial rotary structure is proposed,which can transfer linear motion to high-speed inertial rotary movement,and its operating principle and dynamic model are also analyzed in detail.The experimental results indicate that the energy harvester can collect 85.2 mJ of energy from one step of an adult,and the instantaneous output power can reach up to 32.2 mW.Through continuously collecting the energy generated by human walking,the energy harvester can successfully drive a wireless sensor health monitoring system to operate normally.Furthermore,by optimizing the device size and structure,the energy harvester can also be applied to collect ocean wave energy with 112.2 mW of average output power and 58.87μW/cm~3 of power density.The effects of device structure parameters and external excitation conditions on the output are also explored.