Nonlinear Hybrid Bistable Vibration-Energy-Harvester Modeling Considering Magnetostrictive and Piezoelectric Behaviors

Abstract

The present study investigates a novel two degrees of freedom (2DOF) modeling of hybrid-bistable vibration energy harvester (VEH) considering nonlinear magnetic interaction and elastic magnifier to improve the efficiency and expand the action bandwidth. The main part of harvesting mechanism is a composite cantilever beam consists of three layers of magnetostrictive, piezoelectric and a metallic core with internal damping. Such a novel architecture generates more electrical power and operates at larger bandwidth than common piezoelectric or magnetostrictive energy harvesting systems. In the present work, a coupled 2DOF model is developed to investigate the vibration behavior and energy harvesting rate of the harvester. The harmonic balance method is used to obtain the frequency responses and then the Runge-Kutta method is utilized to calculate the dynamic responses. A parametric study is done to investigate the effects of the key features of the harvester such as magnets distances, base acceleration level and excitation frequency on the rate of electricity generation.