A Piezoelectric MEMS Harvester Suitable Adopt a New Two-Degree-of-Freedom Structure

Abstract

In this work, we presented a piezoelectric energy harvester adopt a new two-degree-of freedom that can work at both 1st and 2nd resonant frequency. First, the inherent frequency the displacement situation were described through the Finite element simulation software. Subsequently, this device was achieved by bonding the thinned PZT onto a flexible phosphor bronze substrate, and lancing a U-shaped in order to constitute the two degree freedom structure. Two additional tungsten mass were respectively assembled at the tops of the main beam and the second beam to reduce the 1st and 2nd resonant frequency of the harvester. The experimental results show the maximum open-circuit output voltage and output power of the main beam can reach up 18.8 V when it worked at 1st resonant frequency. For the 2nd resonant frequency, the maximum open- circuit output voltage of second beam can reach up 5.44 V.