Two-dimensional concentrated-stress low-frequency piezoelectric vibration energy harvesters

Abstract

Vibration-based energy harvesters using piezoelectric materials have long made use of the cantilever beam structure. Surmounting the deficiencies in one-dimensional cantilever-based energy harvesters has been a major focus in the literature. In this work, we demonstrate a strategy of using two-dimensional beam shapes to harvest energy from low frequency excitations. A characteristic Zigzag-shaped beam is created to compare against the two proposed two-dimensional beam shapes, all of which occupy a 25.4 × 25.4 mm2 area. In addition to maintaining the low-resonance bending frequency, the proposed beam shapes are designed with the goal of realizing a concentrated stress structure, whereby stress in the beam is concentrated in a single area where a piezoelectric layer may be placed, rather than being distributed throughout the beam. It is shown analytically, numerically, and experimentally that one of the proposed harvesters is able to provide significant increase in power production, when the base acceleration is set equal to 0.1 g, with only a minimal change in the resonant frequency compared to the current state-of-the-art Zigzag shape. This is accomplished by eliminating torsional effects, producing a more pure bending motion that is necessary for high electromechanical coupling. In addition, the proposed harvesters have a large effective beam tip whereby large tip mass may be placed while retaining a low-profile, resulting in a low volume harvester and subsequently large power density.

Ultralow frequency acoustic bandgap and vibration energy recovery in tetragonal folding beam phononic crystal

“…Model 1 is arranged regularly in plane XY, lattice constant a = 34 mm, the central mass is a square with the side length H of 20 mm, the tetragonal folding beam width b = 1.43 mm, gap length e = 2.14 mm. Model 1 been studied and verified in the field of vibration energy recovery [24][25][26].…”

“…In recent years, fold beam structures have been studied and verified in the field of vibration energy recovery. [24][25][26] In order to solve these problems and expand the application of PCs, the TF-BPC and its complementary structure are introduced in this paper. We investigate the dispersion curve relationships, transmission spectra and eigenmodes of TFBPC firstly.…”

Impacts of stopper type and material on the broadband characteristics and performance of energy harvesters

“…Converting ambient vibrational energy into useful electric power through energy harvesters has been increasingly attracted worldwide attention due to its potential application in realizing self-powered operation of wearable electronics [1][2][3] or replacing traditional batteries which are difficult and expensive to maintain. 4,5 Three transduction mechanisms like electrostatic, [6][7][8] electromagnetic [9][10][11][12][13] and piezoelectric [14][15][16][17][18][19][20] have been widely utilized for energy harvesting from mechanical vibrations.…”

Experimental investigation of fan-folded piezoelectric energy harvesters for powering pacemakers

“…Fan-folded configuration [17–21], elephant [22] and zig-zag [23] structures allow getting low natural frequency in small size devices. However, none of the previous studies has looked into building an MRI compatible energy harvester for leadless pacemakers.…”