Analytical model with two degree of freedom of piezo‐magneto‐elastic energy harvester for low‐frequency wide bandwidth applications

Abstract

Vibration-based nonlinear energy harvester has acknowledged great effort to harvest power out of low-frequency wideband applications. The nonlinear analytical model of a cutout two degree of freedom piezo-magneto-elastic energy harvester is developed to obtain electrical responses of wide bandwidth in between first two successive lower-vibration modes. Specifically, the nonlinear static tip displacements, mechanical potential energy, modified nonlinear stiffness and tuned resonant frequencies are analytically obtained as a function of initial distance between two magnets which include spring and damping effects of each joint of cantilever beams. The numerical models of magnetic force interactions and harvester models are developed using finite element methods to validate the solutions of analytical models along with available experimental data from the literature. Finally, the optimised inner beam length is found to avoid the anti-resonant frequency in between the bandwidth region.