Dynamic analysis of a novel two-sided nonlinear MEMS electrostatic energy harvester

Abstract

In this work, we investigate the frequency response of an electrostatic MEMS energy harvester with innovative gap-overlap transducer design. We prove theoretically and experimentally that this design solution gives rise to a strongly nonlinear behaviour in MEMS dynamics. This is the first time that this phenomenon is demonstrated in a gap-overlap electrostatic MEMS along with a theoretical explanation. When increasing the bias voltage, the frequency response shifts towards lower frequencies while bending towards higher ones. The main consequence of this bending is a significant increase of the system bandwidth (+280 % compared to a linear situation with no bias voltage for the same device) when the bias voltage increases up to 30 V. A proposed gap-overlap transducer configuration is demonstrated to be a simple and efficient solution for MEMS energy harvester bandwidth increase.