Enhancing Aeroelastic Wind Energy Harvesting Using Quasi-Zero Stiffness

A quasi-zero stiffness (QZS) two degree-of-freedom (DOF) galloping piezoelectric energy harvester (GPEH) is proposed for efficient energy harvesting in the ultra-low wind speed range. At low wind speeds, traditional 1DOF and 2DOF linear harvesters are not capable of generating enough voltage to power microelectronics; moreover, the bistable harvester tends to be trapped in intrawell motion, which is unfavorable for wind energy harvesting. With the feature of a low dynamic frequency, the QZS nonlinear mechanism is applied to remarkably decrease the onset galloping wind speed and boost the power generation. A coupled aero-electro-mechanical model is built to evaluate the characteristics of the harvester. The simulation result shows that the 2DOF QZS-GPEH has the best output performance at low wind speeds, outperforming its 1DOF linear, 2DOF linear, and 2DOF bistable counterparts. This work opens new opportunities for efficiently harvesting wind energy at the ultra-low wind speed region.