Enhanced frequency synchronization for concurrent aeroelastic and base vibratory energy harvesting using a softening nonlinear galloping energy harvester

Abstract

This paper proposes a softening nonlinear aeroelastic galloping energy harvester for enhanced energy harvesting from concurrent wind flow and base vibration. Traditional linear aeroelastic energy harvesters have poor performance with quasi-periodic oscillations when the base vibration frequency deviates from the aeroelastic frequency. The softening nonlinearity in the proposed harvester alters the self-excited galloping frequency and simultaneously extends the large-amplitude base-excited oscillation to a wider frequency range, achieving frequency synchronization over a remarkably broadened bandwidth with periodic oscillations for efficient energy conversion from dual sources. A fully coupled aero-electro-mechanical model is built and validated with measurements on a devised prototype. At a wind speed of 5.5 m/s and base acceleration of 0.1 g, the proposed harvester improves the performance by widening the effective bandwidth by 300% compared to the linear counterpart without sacrificing the voltage level. The influences of nonlinearity configuration, excitation magnitude, and electromechanical coupling strength on the mechanical and electrical behavior are examined. The results of this paper form a baseline for future efficiency enhancement of energy harvesting from concurrent wind and base vibration utilizing monostable stiffness nonlinearities.

Piezoelectric vibration energy harvester: Operating mode, excitation type and dynamics

“…When the wind speed exceeds the critical wind speed, the piezoelectric and electromagnetic modules will work together. Chen et al 176 proposed a softened nonlinear aeroelastic dance energy harvester that harvests energy from wind and foundation vibrations. Karami et al 177 developed a new compact nonlinear piezoelectric wind harvester, a structure that stabilizes a piezoelectric biaxial by repelling magnetic forces.…”

A broadband zigzag-shaped energy harvester for both wind energy and vibration energy: modeling and experimental verification

“…The experimental results demonstrated that the amplitude of voltage output increased by 53%, and the bandwidth achieved was ten times wider compared with the linear galloping harvester. Chen et al [34] presented a softening nonlinear aeroelastic galloping energy harvester for enhanced energy harvesting from concurrent wind flow and base vibration. The softening nonlinearity of the proposed harvester modulated the selfexcited galloping frequency and simultaneously enlarged the frequency range of the large-amplitude base-excited oscillation.…”