Energy harvesting in a nonlinear piezomagnetoelastic beam subjected to random excitation

•Bistable piezomagnetoelastic generator subjected to random excitations is analyzed.•Performance is enhanced when system oscillates around all stable equilibrium points.•Numerical and experimental approaches show good qualitative agreement.•A relationship between the variance of excitation and potential energy is defined.•A desired region, where the performance of bistable system is enhanced, is defined.

This work addresses the influence of nonlinearities in energy harvesting from a piezomagnetoelastic structure subjected to random vibrations. Nonlinear equations of motion that describe the electromechanical system are given along with theoretical simulations. The numerical analysis presents a comparison between the voltage provided from a linear, nonlinear bistable and nonlinear monostable systems due to random vibration. Experimental performance of the generator exhibits qualitative agreement with the theory, showing an enhancement of piezoelectric power generation in a bistable system when it vibrates around both stable equilibrium points. A relationship between variations in the excitation and a bistable system response is established from numerical simulations, defining a region of enhanced power generation when compared to the linear and nonlinear monostable cases.