非对称势阱对三稳态压电俘能器性能的影响分析

为了探讨具有非对称势能函数的三稳态压电俘能器的优点,提出了一种具有不对称势能函数的三稳态结构。基于广义Hamilton变分原理,考虑梁端磁铁偏心距和转动惯量的影响,建立了非对称三稳态压电悬臂梁俘能系统的动力学方程,利用龙格-库塔法和多尺度法分析了初始振动点、外界激励等对存在非对称势阱的磁力式三稳态压电俘能系统响应的影响。结果表明:合适的起振位置和外部激励频率能使系统进入高能轨道,产生大幅阱间运动,提高系统的俘能效率。相比于忽略梁端磁铁偏心距和转动惯量的传统模型,修正模型的系统阱间运动频带宽度及输出功率峰值的计算结果均明显增大。

Influence of asymmetric potential wells on the performance of triple-stable piezoelectric energy harvesters

In order to explore the advantages of a triple-stable piezoelectric trap with asymmetric potential energy function, a triple-stable structure with asymmetric potential energy function is proposed. Based on the generalized Hamilton variational principle and considering the influence of the eccentricity and the rotary inertia of the end magnet at the end of the beam, the differential equation of motion for an asymmetric triple-stable piezoelectric cantilever beam energy capture system is established. The effects of the starting position and excitation conditions on the triple-stable piezoelectric energy harvesting system with asymmetric potential function are studied by Runge-Kutta method and multi-scale method. The results show that the appropriate starting position and external excitation frequency can make the system enter high-energy orbit and then generate large inter-well motion, so improve the energy harvesting efficiency of the system. Compared with the traditional model, which neglects the eccentricity and the rotary inertia of the end magnet, the frequency bandwidth and the peak power of the modified model system have significantly increased.