A piezoelectric energy harvester with a hybrid nonlinearity of bluff body and magnet repulsion in low threshold wind speed for power supply

The environment contains several substantial energies, such as low-speed wind, which can be harvested to power sensors for environment monitoring, data collection, etc. As a promising solution, a piezoelectric energy harvester with hybrid nonlinearity for low threshold wind speed and practical wind speed range is introduced in this paper. Because of the hybrid nonlinearity of bluff body and magnet, the symmetrically shaped bluff body can induce a greater cantilever deformation, and a stronger repulsion generates a higher swing frequency of the cantilever. Moreover, the dual lead zirconate titanate plate enhances the utilization efficiency of the magnet repulsion. The hybrid nonlinearity is studied in theoretical models, numerical simulations, and experiments. The harvester outputs a noticeable voltage at 2.5 m s⁻¹. The highest output peak-to-peak voltage and power came to 33.72 V_P–P, 0.346 mW in 5.5 m s⁻¹, 800 kΩ. The application experiments also demonstrate the feasibility and stability of the harvester by powering LEDs and sensors, which enable sensors to be placed in a wider range with high stability for environment monitoring.