Nonlinear Analysis of the Tristable Energy Harvester with a Resonant Circuit for Performance Enhancement

The tristable energy harvesters (TEH) can achieve broadband energy harvesting performance from low frequency and low level excitations. Previous studies mainly focused on the tristable energy harvesting structure that is connected to a pure resistor. This paper presents an enhanced TEH with a series resistor-inductor resonant (RL) circuit connected to the piezoelectric layers. The influence of the resonant frequency of the circuit, the excitation level, and equilibrium positions on dynamic responses is analyzed using modern methods of nonlinear dynamics. The results demonstrate that the proposed TEH undergoes the periodic and chaotic motions alternatively along with the increase of the resonant frequency of the RL circuit. Furthermore, the TEH with a RL circuit dramatically enhances the energy harvesting efficiency, and simultaneously slightly decreases the vibration response. The presented TEH with a RL circuit will open a new page in the nonlinear energy harvesting technology.