Rotational Vibration-Based Piezoelectric Energy Harvesting with Bandwidth Enhancement Through Magnetic Oscillators

Energy harvesting technology has seen increasing growth recently with the advancements of low-power wireless devices in remote sensing technologies. The narrowband behavior of traditional energy harvesters becomes a major limitation for a long-term deployment with dynamic inputs. Rotating systems provide a unique nonlinear operating behavior that can be utilized in sensors and automation. This paper proposes a piezoelectric energy harvester fixed on one side of a rotating disk that can be used for rotational energy harvesting applications. The gravitational forces and magnetic couplers attached at the ends of the beam provide broadband behavior and can increase voltage output. An analytical model was derived from Euler–Bernoulli’s beam theory for the magnetically coupled structure with a macro-fiber composite. Finite element analysis was conducted to examine the different mode shapes and approximate the performance output of rotational piezoelectric energy harvesting (RPEH). The results show that adding magnetic couplers introduces bandwidth enhancement properties. The maximum voltage output of coupled models reached up to 1.3 V with an optimal separation distance of up to 3000 rpm.