Dual-function quasi-zero-stiffness dynamic vibration absorber: Low-frequency vibration mitigation and energy harvesting

Abstract

The dynamic vibration absorber (DVA) can effectively suppress undesirable vibration of a host structure, and the energy harvester is also proven to be a feasible way to collect vibration energy from the host structure. However, it is almost impossible to achieve high-efficiency vibration attenuation and energy harvesting at ultra-low frequency by conventional methods. In this paper, a dual-function quasi-zero-stiffness (QZS) energy harvesting dynamic vibration absorber (EHDVA) is proposed to mitigate vibration and harvest energy simultaneously. The proposed device mainly composed of a QZS absorber and an electromagnetic transducer. The quasi-zero stiffness is realized using a vertical spring connecting with two oblique springs in parallel. The electromagnetic transducer consists of permanent magnets and coils, and any relative motion between the permanent magnets and coils brings flux linkage variation and generate induced voltage. Firstly, the theoretical model of the QZS EHDVA is established and the statics analysis of QZS absorber is carried out. Then, the Harmonic Balance Method (HBM) along with numerical path continuation is applied to solve the electromechanical coupled equations of the QZS EHDVA. Moreover, both numerical and analytical methods are used to evaluate the influence of mechanical and electrical parameters on performances of vibration absorption and energy harvesting. Finally, the H∞ optimization on system parameters of the QZS EHDVA are conducted with the aid of perturbation method. It indicates that the optimized QZS EHDVA can considerably reduce resonance peaks of the host oscillator at ultra-low frequency and effectively enhance energy harvesting at the same time.