双稳态电磁式振动能量捕获器超谐波响应研究

超谐波响应是非线性振动系统在较大激励下表现的特性,在某种条件下双稳态振动能量捕获系统的超谐波响应可使系统产生优越的输出功率。本文将质量-非线性弹簧-阻尼系统与双稳态振动能量捕获器相结合,提出了附加非线性振子的双稳态电磁式振动能量捕获器,建立系统的力学模型及控制方程。采用两项式谐波平衡法,获得了双稳态系统在简谐激励下产生大幅运动的基谐波和超谐波响应的解析解,借助数值仿真分析了质量比和调频比对双稳态振动能量捕获器产生大幅运动的影响规律,获得了双稳态系统的结构参数的最佳配置范围,且当外部激励频率处于低频段时,系统发电主要表现为超谐波发电,随着激励频率的增大,振动发电系统主要呈现基谐波发电。上述研究,为双稳态能量捕获装置的理论研究提供了参考。

Research on the superharmonic effects of bistable electromagnetic vibration energy harvester

Superharmonic effects are characteristic of many nonlinear vibration systems undergoing high levels of excitation.As far as bistable vibration energy harvester are concerned,superharmonic effects can make the vibration energy harvester yield superior electrical power.The bistable electromagnetic vibration energy harvester with auxiliary nonlinear oscillator is put forward by combining the mass-nonlinear spring-damper system and the bistable vibration energy harvester system.The mechanical model and governing equations of the bistable electromagnetic vibration energy harvester are obtained.The analytical solutions of the fundamental and superharmonic effects of the harvester are obtained by means of the harmonic balance method with two-term solution formulation.The effects law of mass ratio and tuning ratio on the large amplitude motion of bistable vibration energy harvester are obtained by simulation.The optimum ranges of structural parameters are determined.Furthermore,superharmonic power generation is prominent when the harvester is excited by the external excitation signal with lower frequency while fundamental power generation become prominent when the excitation frequency increases.The above research results can provide a basis for the study of the bistable electromagnetic vibration energy harvester.