A Two-Port Nonlinear Model for Magnetoelastic Energy-Harvesting Devices

The aim of this paper is to present a two-port equivalent circuit that is able to describe the main features of an energy-harvesting device based on magnetoelastic materials. The magnetomechanical model behind the equivalent circuit is nonlinear and fully coupled. Therefore, the most part of the typical real-device behavior, without the limits of linear magnetomechanical modeling, is described. A preliminary validation of the model, by exploiting experimental data, is provided. Moreover, simulation tests and comparisons to the linear model are also carried out to underline the basic features of the proposed nonlinear approach. To this end, numerical results of the harvested power and peak voltage for the two devices in different working conditions are presented and discussed.