A piezoelectric energy harvester with a mechanical end stop on one side

Nonlinear effects as severe as proof mass impact on mechanical end stops are potentially useful for energy harvesting. In this paper, we present measurements and modeling of a piezoelectric energy harvester with a mechanical end stop on one side. At high acceleration levels we observe nonlinear effects related to impacts on the end stop such as an enlarged up-sweep bandwidth in frequency sweeps. Based on SPICE simulations of an electrical equivalent circuit for the device, we show that modeling of the end stop as a parallel spring-dashpot system is sufficient to recapture the energy harvester behavior.