Nonlinear Dynamics and Energy Harvesting of a Two-Degrees-of-Freedom Electromagnetic Energy Harvester near the Primary and Secondary Resonances

Energy harvesting is a useful technique for various kinds of self-powered electronic devices and systems as well Internet Things technology. This study presents two-degrees-of-freedom (2DOF) electromagnetic energy harvester that can use environment vibration provide small devices. The proposed consists cylindrical tube with two moving magnets suspended by magnetic spring mechanism stationary coil. In order to verify the theoretical model, prototype was constructed tested. influence key parameters, including excitation acceleration, response harmonic frequency sweep, electromechanical coupling on generated characteristics harvester, investigated. experimental results showed able increase resonance bandwidth (60–1200 rad/s) output power (0.2 W). However, due strong nonlinearity, an unstable region occurred near main first resonance, which resulted from Neimark–Sacker bifurcation.