Design and characteristic analysis of a high-performance deformable piezoelectric wind energy harvester based on coupled vibrations

The current vortex-induced vibration piezoelectric wind energy harvesters have a narrow operating wind speed range, while galloping piezoelectric energy harvesters are at risk of damage from excessive amplitude at high wind speeds, a novel high-performance deformable piezoelectric wind energy harvester based on coupled vibrations (DPWEH) has been proposed. The alteration of the compound blunt body shape effectively modifies the shedding characteristics and intensity of vortices, subsequently influencing the vibration mode and output voltage of the system. The vibration mode transitions from galloping to coupled vibration, ultimately to vortex-induced vibration. The rigid wing and long elastic beam suppress galloping at high wind speeds. A thinner flexible wing can extend the duration of coupled vibration. A smaller wing width ratio and larger Y-type base wing width are beneficial for increasing the output voltage. By optimizing the parameters of the compound blunt body, the onset wind speed can be effectively reduced, the effective wind speed bandwidth can be expanded, and the DPWEH can undergo coupled vibration for an extended duration while stably generating electricity. The peak output power is 0.36 mW at a load of 150 kΩ. Moreover, the energy harvester demonstrates the prolonged power generation capability of signal transmitters and 100 LED lights.