Numerical Simulations of Energy Harvesting in a Portal Frame Coupled with a Nonlinear Energy Sink

This chapter presents the investigation of energy harvesting in a portal frame coupled with a nonlinear electromagnetic energy sink (NES), excited by an unbalanced DC motor, representing a nonideal excitation source. The energy harvesting is performed by two sources: a piezoelectric material and the energy generated by the electromagnetic energy sink. The coupling of the structure with the piezoelectric material and the electromagnetic energy sink resulted in a nonlinear electromechanical coupling model. The main advantage of nonlinear energy harvesters is the conversion of energy over a wider range of frequencies of vibrations. For dynamics, the analysis of the system considers bifurcation diagrams, phase portraits, power spectral densities, and 0-1 tests. Numerical simulations show the existence of chaotic behavior for some regions of the parameter space. Additionally, to control the vibration amplitudes of the structure and improve energy production, an adjustment of the parameters of the nonlinear electromagnetic energy sink is proposed.