基于双环永磁体结构的多稳态能量采集器建模及性能分析

Modeling and Analysis of Multi-stable Energy Harvesters Based on Double-ring Permanent Magnets

宽频带能量采集已经成为当前国际上振动能量采集的研究热点之一。提出基于双环永磁体结构的非线性多稳态能量采集器。采用库伦模型建立双环永磁体磁力数学模型,分析外环永磁体结构参数对能量采集装置势能函数的影响规律,确定能量采集器在单稳态、双稳态到三稳态之间变化时外环永磁体结构参数范围。通过数值仿真分析能量采集器处于双稳态和三稳态状态时在不同激励加速度幅值和不同激励频率下的动力学响应特性及其电压输出特性。结果表明可以通过调整外环永磁体参数对所提出基于双环永磁体结构的多稳态能量采集器多稳态的状态进行调节,同时三稳态状态下的能量采集带宽显著优于双稳态状态下的采集带宽,电压输出幅值也优于双稳态状态下的能量采集器。最后对比能量采集器处于不同稳态状态时的吸振效果,结果表明能量采集装置处于三稳态状态时吸振性能最好。

Broadband energy harvesting has become one of the international research hotspots of vibration energy harvesting.A multi-stable energy harvester based on double-ring permanent magnets is proposed.A mathematical model of magnetic force of the double-ring permanent magnets is established by using the Coulomb model.The influence of the parameters of the outer ring on the potential energy function is analyzed.The parameter range of the outer ring when the energy harvester changes from single stable,bi-stable to tri-stable state is determined.The dynamic response and voltage output characteristics of the energy harvester under different excitation acceleration amplitudes and frequencies in the bistable and tri-stable states are analyzed through numerical simulation.The result shows that the states of the multi-stable energy harvester based on the double-ring permanent magnets can be adjusted by changing outer ring parameters.The energy harvesting bandwidth in the tri-stable state is much better than that in the bi-stable state,and the voltage output amplitude of the energy harvest in the tri-stable state is also better than that of the energy harvester in the bi-stable state.Finally,the vibration suppression efficiencies of different steady-state energy harvesters are compared.The results show that the energy harvester has the best vibration absorption effect when it is in the tri-stable state.