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

In this work, a novel zigzag-shaped energy harvester is proposed to harvest wind energy and vibration energy simultaneously in a practical environment. The harvester is constituted of an inclined beam and a horizontal beam with a bluff body fixed at the free end. The inclined beam is covered by a piezoelectric patch. The vibration induced by the wind flow and base excitation produces electric energy through the piezoelectric material and realizes energy harvesting. In particular, the softening characteristic created by the magnetic interaction can extend the working bandwidth. Dynamical coupling equations are derived, and the corresponding simulations are carried out. The results show that the cubic bluff body can help increase the wind-induced energy harvesting. The responses obtained under base excitation combined with wind flow demonstrate that the hybrid excitation can provide a significant enhancement to the non-resonance region. Related validation experiments are carried out. The experimental results are in good agreement with the numerical results. Compared with the conventional base excitation or wind flow excitation, the output power obtained under hybrid excitation increases by 106% and 206%, respectively.