Modeling, Simulation and Optimization of Piezoelectric Bimorph Transducer for Broadband Vibration Energy Harvesting in Multi-Beam and Trapezoidal Approach

Abstract

The objective of the research is to design a broadband energy harvester device through the multi-beam approach and non-linear trapezoidal geometry approach. The performance of the composite piezoelectric PZT-PZN polycrystalline ceramic material is simulated using COMSOL Multiphysics, and results are compared using series configuration of a composite bimorph energy harvester which vibrates at its 1st fundamental frequency. We chose a five cantilever multibeam harvester to demonstrate that individual fundamental modes of the beams can achieve a broader frequency band and generate power. Authors also show that composite trapezoidal beam design leads to high power density broadband frequency response. The multibeam approach resulted in broader bandwidth of 18 Hz while generating a power density of 0.0913 mW/cm3 whereas the trapezoidal shape generated 2.3 – 2.5 mW/cm3 with a bandwidth of 4 to 6 Hz. Authors believe that these results could help design broadband energy harvesters to enhance power density as well as bandwidth.

Design, Modeling, and Simulation of Two‐Piece Trapezoidal Piezoelectric Devices for Sensing and Energy Harvesting

“…It is shown that increasing the width W 2 (at free end) lowers the resonance frequency, which agrees with our results. It was also shown that the trapezoidal shape generates higher voltage compared to the simple rectangular cantilever beam bimorph which matches our findings in previous works [6,12]. In this paper, we explore a unique design of 2-piece trapezoidal shaped piezoelectric bimorph to understand its effects on harvested power, power density, and bandwidth.…”

“…Equation (30) is substituted into equation (26). erefore, equation (26) can be rewritten to the integral formula in 6 Advances in Materials Science and Engineering equation 31, where w 1 is the shorter width of the bimorph and w 2 is the longer width of the bimorph:…”

“…Advances in Materials Science and Engineering [6], the two-piece trapezoidal beam design has the potential to increase the energy harvester's power output and the frequency bandwidth. e authors proposed two new twopiece trapezoidal beam designs which are shown in Figure 7.…”

“…is work addresses the goal on designing a two-piece trapezoidal composite bimorph piezoelectric energy harvester operating in the transverse mode with the aim to enhance the maximum real power density in an electric circuit with an optimal resistor, as well as the full-width half-maximum (FWHM) power density-mechanical vibration broadband performance, compared them with the results of the one-piece trapezoidal beam design based on the PZT-PZN-Scheme 4 polycrystalline ceramic piezoelectric material: 0.8 [Pb (Zr 0.52 Ti 0.48 )O 3 ]-0.2 [Pb (Zn 1/3 Nb 2/3 )O 3 ] from our previous work on the one-piece trapezoidal beam model [6,7]. e PZT-PZN-Scheme 4 material was reported because of its superior structural power density (0.1713 mW/cm 3 measured): 20.97% higher than that of PZT-ZNN-Scheme 2 (0.1416 mW/cm 3 ), 15.38% higher (49.5 mW/cm 3 measured) in the electric power output, and 31.13% higher (0.499 mW/cm 3 measured) in the piezoelement power density, as the "two-step sintering" method was used to reduce grain size and increase density, which leads to higher relative dielectric (ε r is 1588, 2.95∼4.23 times higher than those of PZT-ZNNs) and the piezoelectric property of PZN-PZN-Scheme 4 material (the charge constant in the thickness mode d 33 is 400 pC/N, 2.4∼2.6 times higher than that of PZT-ZNNs.…”

“…e two-piece Table 3: FWHM bandwidth, the min./max. real power density of various trapezoidal bimorph beams [6,8]. e one-piece trapezoidal bimorph design has the same dimension of the two-piece trapezoidal bimorph for the comparison.…”