Study of Cantilever Structures Based on Piezoelectric Materials for Energy Harvesting at Low Frequency of Vibration

Abstract

In this work is presented a study of a piezoelectric energy harvesting device used for low power consumption applications operating at relative low frequency. The structure consists of a cantilever beam made by Lead Zirconate Titanate (PZT) layer with two gold electrodes for electrical contacts. The piezoelectric material was selected taking into account its high coupling coefficients. Different structures were analyzed with variations in its dimensions and shape of the cantilever. The devices were designed to operate at the resonance frequency to get maximum electrical power output. The structures were simulated using finite element (FE) software. The analysis of the harvesting devices was performed in order to investigate the influence of the geometric parameters on the output power and the natural frequency. To validate the simulation results, an experiment with a PZT cantilever with brass substrate was carried out. The experimental data was found to be very close to simulation data. The results indicate that large structures, in the order of millimeters, are the ideal for piezoelectric energy harvesting devices providing a maximum output power in the range of mW

Improvements in energy harvesting capabilities by using different shapes of piezoelectric bimorphs

“…To validate the obtained formula in equation ( 54), for the output voltage of a bimorph cantilever energy harvester, a finite element simulation is carried out for different beams, which consists of a brass substrate layer between two PZT-5 A layers with ρ = 8490 Pa, and different geometrical parameters described in table 3 according to [18]. The Poling direction is taken parallel to the Z-axis.…”