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Title: Multiple-Scale Analysis of a Tunable Bi-Stable Piezoelectric Energy Harvester
Abstract This paper presents the theoretical modeling and multiple-scale analysis of a novel piezoelectric energy harvester composed of a metal cantilever beam, piezoelectric films, and an axial preload spring at the moveable end. The harvester experiences mono- and bi-stable regimes as the stiffness of preload spring increases. The governing equations are derived with two high-order coupling terms induced by the axial motion. The literature shows that these high-order coupling terms lead to tedious calculations in the stability analysis of solutions. This work introduces an analytical strategy and the implementation of the multiple-scale method for the harvester in either the mono- or bi-stable status. Numerical simulations are performed to verify the analytical solutions. The influence of the electrical resistance, excitation level, and the spring pre-deformation on the voltage outputs and dynamics are investigated. The spring pre-deformation has a slight influence on the energy harvesting performance of the mono-stable system, but a large effect on that of the bi-stable system.  more » « less
Award ID(s):
1935951
PAR ID:
10282543
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
ASME Letters in Dynamic Systems and Control
Volume:
1
Issue:
2
ISSN:
2689-6117
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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