A Broadband Vibration-Based Energy Harvester Using an Array of Piezoelectric Beams Connected by Springs

Abstract EN

Piezoelectric cantilevered beams have been widely used asvibration-based energy harvesters.

Nevertheless, these deviceshave a narrow frequency band and if the excitation is slightlydifferent there is a significant drop in the level of powergenerated.

To handle this problem, the present investigationproposes the use of an array of piezoelectric cantilevered beamsconnected by springs as a broadband vibration-based energyharvester.

The equations for the voltage and power output of thesystem are derived based on the analytical solution of thepiezoelectric cantilevered energy harvester with Euler-Bernoulli beam assumptions.

To study the advantages and disadvantages of the proposed system,the results are compared with those of an array of disconnectedbeams (with no springs).

The analytical model is validated withexperimental measurements of three bimorph beams with and withoutsprings.

The results show that connecting the array of beams withsprings allows increasing the frequency band of operation and increasing the amount of power generated.