Purpose

Integrating a piezoelectric nonlinear energy sink (NES) to a host structure has recently been used to realize simultaneous vibration control and energy harvesting. This paper investigates a piezoelectric NES system connected with a resistive load, revealing the influence of the electromechanical coupling on the nonlinear dynamic phenomena and the consequent energy harvesting performance under impulsive and harmonic excitations.

Methods

For impulsive excitation, the periodic orbits of the electromechanical system are analysed based on the complexification-averaging method and validated by the wavelet transform of the damped response from numerical simulations. For harmonic excitation, the steady-state response of the displacement and power output can be obtained by the utilization of the Newton-enabled harmonic balance method (NHBM) and numerical simulations.

Results

The frequency–energy plot shows the evolution of the backbone branches due to the equivalent electrical stiffness induced by the piezoelectric transducer. Furthermore, for the steady-state response, the influence of the electromechanical coupling on the vibration suppression performance, the harvested power as well as the operational bandwidth are illustrated.

Conclusion

In addition to the direct effect on the energy conversion efficiency, the results indicate that the increase of electromechanical coupling will eventually deactivate energy localization phenomenon in the NES for both impulsive and harmonic excitation, which will also affect the energy harvesting performance.

中文翻译：

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机电耦合对压电非线性能量吸收器系统动态特性的影响

目的

最近，将压电非线性能量吸收器（NES）集成到主体结构中已实现了同时的振动控制和能量收集。本文研究了与电阻负载连接的压电NES系统，揭示了机电耦合对非线性动力现象的影响以及在脉冲和谐波激励下的能量收集性能。

方法

对于脉冲激励，基于复数平均法分析了机电系统的周期轨道，并通过数值模拟的阻尼响应的小波变换对其进行了验证。对于谐波激励，可以通过使用牛顿启用的谐波平衡方法（NHBM）和数值模拟来获得位移和功率输出的稳态响应。

结果

频率-能量图显示了由于压电换能器感应的等效电刚度而导致的主干分支的演变。此外，对于稳态响应，还说明了机电耦合对减振性能，所收集的功率以及工作带宽的影响。

结论

结果表明，除了直接影响能量转换效率外，机电耦合的增加还将最终使NES中的能量局部化现象（无论是脉冲激发还是谐波激发）失活，这也将影响能量采集性能。