Nonlinear Behavior of an Electrostatic Energy Harvester Under Wide- and Narrowband Excitation

This paper investigates an electrostatic vibration energy harvester that displays rich nonlinear behavior including jumps during frequency sweeps and broadening of the spectrum with increasing levels of broadband vibration. We demonstrate that the measured nonlinear phenomena can be adequately described by a lumped model with a nonlinear beam displaying both spring softening and hardening. Our results show that considerable bandwidth enhancements can be achieved by use of nonlinear springs without relying on mechanical stopper impacts, resonance tuning, or large electromechanical coupling.