Design and performance analysis of internal resonance based frequency up-converting piezoelectric oscillator applied in ultra-low-frequency vibration energy harvesting
摘要自然环境中的低频、超低频振动能分布十分广泛,但如何高效俘获依然是一个技术难题。本文主要研究了一种基于摆锤、内嵌式双悬臂梁、一对永磁铁和限位器的升频式超低频振动能量收集器,并对其进行了理论建模、仿真分析和实验验证。该振子结构可以利用1:2:6升频转换机制将初始激励的超低频率升高至6倍频的电压输出,有效地增大了压电元件的换能效率,提高了振子结构输出功率。该原型装置可以在频率2 Hz、幅值0.2 m/s 的激励下达到1.4 mW的能量收集水平,展现出了较高的能量俘获和转换潜力。
Abstract:Low frequency and ultra-low frequency vibration energy exists widely, but how to efficiently harvest it is still a technical problem. The paper presents an ultra-low-frequency vibration energy harvester based on the pendulum, the embedded double-cantilever beams,a pair of magnets and two mechanical stoppers by theoretical modeling, simulation analysis and experimental verification. The oscillating structure can convert the initial low-frequency excitation to 6-time-frequency voltage output based on 1:2:6 frequency-up-conversion mechanism, effectively improve the energy conversion efficiency of piezoelectric elements, and increase the output power of the oscillating structure. The prototype can reach the energy harvesting level of 1.4 mW at the excitation of 2 Hz and 0.2 m/s, presenting great potential for application.