Design Parameters and Asymmetric Structure for Cantilever-based MEMS Piezoelectric Energy Harvesters

A MEMS Piezoelectric energy harvester has been simulated. The energy harvester is based on a bimorph piezoelectric cantilever beam. The effects of design parameters such as cantilever geometry, piezo layers thicknesses and proof mass material on the maximum output voltage and the resonant frequency have been studied. The output voltage of the MEMS energy harvester has been calculated and its geometry dependence has been discussed. As a new design, the asymmetric structure composed of a piezoelectric layer on top surface and another piezo layer with different thickness on the bottom surface of the cantilever has been proposed and compared to symmetric structure. The results show that the proper definition of geometry parameters has a significant effect on the output voltage and resonant frequency. This paper provides a complete guide for designing MEMS cantilever based energy harvesters for specific applications with determined output voltage and power and resonant frequency

Keywords:

Energy harvesters , Cantilever , MEMS , Piezoelectric