非谐振式低频电磁-摩擦电复合振动能收集器

Non-resonant and low-frequency triboelectric-electromagnetic hybridized nanogenerator for vibration energy

针对低频复杂的环境振动能量,本文提出一种非谐振式低频电磁-摩擦电复合能量收集器件.该能量收集器以旋转陀螺为核心部件,具有结构简单、俘能灵敏、鲁棒性强、可360°全方位俘能等优点.通过理论分析与软件仿真,阐述了器件的工作原理;基于线性电机平台,系统研究了振荡频率、振荡幅度对器件输出性能的影响,较好地证明了器件收集振动能量的能力.在2 Hz的振动环境下,摩擦发电单元在20 MΩ负载下的峰值功率约为0.084 mW,电磁发电单元在800Ω负载下峰值功率约为4.61 mW,系统机电转换效率为0.45%.最后结合人体运动能收集,成功验证了该复合能量收集器对低频复杂机械能的收集能力,并通过能量存储单元,实现了计步器自供能的正常工作.本项研究不仅为低频振动能量的高效采集与转换提供了一个崭新的思路,而且在自供电传感网络节点方面具有潜在应用价值.

As the age of the internet of everything begins,the demand for various sensors to communicate with each other is soaring.As the lifeblood of the sensing system,reliable energy supply is the key consideration.Environmental mechanical energy harvesting has been a key technology for self-powering sensing system,which can convert mechanical energy into electric energy.Here,we present a non-resonant triboelectricelectromagnetic hybridized nanogenerator,which can scavenge low-frequency vibration energy from environmental vibration.In the device a rotating gyro is used as a core component.An embedded magnet and four coils arranged evenly around at the bottom of the shell form an electromagnetic generator(EMG),and a piece of triboelectric film pasted on the outer surface of the gyro together with a bottom electrode constitutes a triboelectric nanogenerator,(TENG).With the design of rotating gyro,a high sensitive energy capture can be realized under low frequency and irregular vibration.Under the rotation and revolution of the gyro,the triboelectric and electromagnetic energy will be generated.Through theoretical analysis and software simulation,the working principle of the device is expounded.Based on a linear motor platform,the influences of oscillation frequency and amplitude are systematically studied,and the maximum power of 0.084 mW under a loading resistance of 20 MΩ and 4.61 mW under 800 Ω are obtained at a driving frequency of 2 Hz by the TENG and EMG,respectively.The energy conversion efficiency of the system is 0.45%.Moreover,by placing the devices on the legs and arms of the human body respectively,the ability of the hybridized nanogenerator to capture the simple movement energy of the human body is further verified.After that,a self-powering pedometer module is successfully integrated with the energy storage unit.Under the excitation provided by running a body,the hybridized nanogenerator can provide a 20-s pedometer normal operation after charging a capacitance of 100μF to 3.2 V.This research not only provides a new idea for the efficient acquisition of vibration energy,but also has potential applications in the energy supply of self-powered sensors.