Investigation of a Novel Piezoelectric Harvester for Capturing Rotational Motion

Piezoelectric energy harvesting technology has received great research interest in recent years. To harvest energy from rotational motion, this work proposes a cantilevered piezoelectric energy harvester based on an adjustable rigid parallel connection. The baffle was designed as a carrier for the rigid connection of the piezoelectric beams A, B and C. The theoretical model of the device was established, and equations for voltage and power were derived. The calculated intrinsic frequencies of the piezoelectric beams are consistent with the experimental results. The baffle size, the distance from the baffle to the free end, and the number of rotor bumps were used as variables in the experiments. The experimental results show that the proposed piezoelectric energy harvester can harvest energy across multiple frequency bands. The maximum average power of the proposed piezoelectric energy harvester is 110.49 mW at a load resistance of 10 kΩ and a rotational speed of 240 r/min. The maximum average power of the harvester is 36.44 mW at a load resistance of 10 kΩ and a rotational speed of 60 r/min. The rigid parallel connection not only broadens the energy harvesting bandwidth but also enhances the output performance of the harvester.