scholarly journals An Exact Analytical Solution to Exponentially Tapered Piezoelectric Energy Harvester

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
H. Salmani ◽  
G. H. Rahimi ◽  
S. A. Hosseini Kordkheili
Keyword(s):  
Analytical Solution ◽  
Energy Harvester ◽  
Exact Analytical Solution ◽  
Mode Shapes ◽  
Electric Resistance ◽  
Coupled Equations ◽  
Piezoelectric Energy ◽  
Piezoelectric Beam ◽  
Parallel Connections ◽  
Tip Mass

It has been proven that tapering the piezoelectric beam through its length optimizes the power extracted from vibration based energy harvesting. This phenomenon has been investigated by some researchers using semianalytical, finite element and experimental methods. In this paper, an exact analytical solution is presented to calculate the power generated from vibration of exponentially tapered unimorph and bimorph with series and parallel connections. The mass normalized mode shapes of the exponentially tapered piezoelectric beam with tip mass are implemented to transfer the proposed electromechanical coupled equations into modal coordinates. The steady states harmonic solution results are verified both numerically and experimentally. Results show that there exist values for tapering parameter and electric resistance in a way that the output power per mass of the energy harvester will be maximized. Moreover it is concluded that the electric resistance must be higher than a specified value for gaining more power by tapering the beam.

Heartbeat Energy Harvesting Using the Fan-Folded Piezoelectric Beam Geometry

2015 ◽  
Author(s):  
M. H. Ansari ◽  
M. Amin Karami
Keyword(s):  
Natural Frequency ◽  
Energy Harvester ◽  
Low Frequency ◽  
Mode Shapes ◽  
Vibration Energy ◽  
Vibration Energy Harvester ◽  
Mechanical Coupling ◽  
Energy Harvesters ◽  
Piezoelectric Energy ◽  
Piezoelectric Beam

A three dimensional piezoelectric vibration energy harvester is designed to generate electricity from heartbeat vibrations. The device consists of several bimorph piezoelectric beams stacked on top of each other. These horizontal bimorph beams are connected to each other by rigid vertical beams making a fan-folded geometry. One end of the design is clamped and the other end is free. One major problem in micro-scale piezoelectric energy harvesters is their high natural frequency. The same challenge is faced in development of a compact vibration energy harvester for the low frequency heartbeat vibrations. One way to decrease the natural frequency is to increase the length of the bimorph beam. This approach is not usually practical due to size limitations. By utilizing the fan-folded geometry, the natural frequency is decreased while the size constraints are observed. The required size limit of the energy harvester is 1 cm by 1 cm by 1 cm. In this paper, the natural frequencies and mode shapes of fan-folded energy harvesters are analytically derived. The electro-mechanical coupling has been included in the model for the piezoelectric beam. The design criteria for the device are discussed.

scholarly journals Modeling and Analysis of Upright Piezoelectric Energy Harvester under Aerodynamic Vortex-induced Vibration

Micromachines ◽  
2018 ◽  
Vol 9 (12) ◽  
pp. 667 ◽  
Author(s):  
Jinda Jia ◽  
Xiaobiao Shan ◽  
Deepesh Upadrashta ◽  
Tao Xie ◽  
Yaowen Yang ◽  
...  
Keyword(s):  
Energy Harvester ◽  
Beam Theory ◽  
Longitudinal Direction ◽  
Load Resistance ◽  
Vortex Induced Vibration ◽  
Modeling And Analysis ◽  
Coupled Equations ◽  
Output Performance ◽  
Piezoelectric Energy ◽  
Tip Mass

This paper presents an upright piezoelectric energy harvester (UPEH) with cylinder extension along its longitudinal direction. The UPEH can generate energy from low-speed wind by bending deformation produced by vortex-induced vibrations (VIVs). The UPEH has the advantages of less working space and ease of setting up an array over conventional vortex-induced vibration harvesters. The nonlinear distributed modeling method is established based on Euler–Bernoulli beam theory and aerodynamic vortex-induced force of the cylinder is obtained by the van der Pol wake oscillator theory. The fluid–solid–electricity governing coupled equations are derived using Lagrange’s equation and solved through Galerkin discretization. The effect of cylinder gravity on the dynamic characteristics of the UPEH is also considered using the energy method. The influences of substrate dimension, piezoelectric dimension, the mass of cylinder extension, and electrical load resistance on the output performance of harvester are studied using the theoretical model. Experiments were carried out and the results were in good agreement with the numerical results. The results showed that a UPEH configuration achieves the maximum power of 635.04 μW at optimum resistance of 250 kΩ when tested at a wind speed of 4.20 m/s. The theoretical results show that the UPEH can get better energy harvesting output performance with a lighter tip mass of cylinder, and thicker and shorter substrate in its synchronization working region. This work will provide the theoretical guidance for studying the array of multiple upright energy harvesters.

Design and Experimental Verification of Torsion-Bending Low-Frequency Piezoelectric Energy Harvesters

2016 ◽  
Author(s):  
Hichem Abdelmoula ◽  
Nathan Sharpes ◽  
Hyeon Lee ◽  
Abdessattar Abdelkefi ◽  
Shashank Priya
Keyword(s):  
System Analysis ◽  
Energy Harvester ◽  
Excitation Frequency ◽  
Low Frequency ◽  
Load Resistance ◽  
Mode Shapes ◽  
Low Frequencies ◽  
Piezoelectric Energy ◽  
The Masses ◽  
Tip Mass

We design and experimentally validate a zigzag piezoelectric energy harvester that can generate energy at low frequencies and which can be used to operate low-power consumption electronic devices. The harvester is composed of metal and piezoelectric layers and is used to harvest energy through direct excitations. A computational model is developed using Abaqus to determine the exact mode shapes and coupled frequencies of the considered energy harvester in order to design a broadband torsion-bending mechanical system. Analysis is then performed to determine the optimal load resistance. The computational results are compared and validated with the experimental measurements. More detailed analysis is then carried out to investigate the effects of the masses on the bending and torsion natural frequencies of the harvester and generated power levels. The results show that due to the coupling between the bending and torsion modes of the zigzag structure, highest levels of the harvested power are obtained when the excitation frequency matches the coupled frequency of torsion type for three different values of the tip mass.

Influence of Nonlinear Effects on a Piezoelectric Energy Harvesting Device

2012 ◽  
Author(s):  
Andreza T. Mineto ◽  
Paulo S. Varoto
Keyword(s):  
Energy Harvester ◽  
Electrical Power ◽  
Nonlinear Effects ◽  
Analytical Investigation ◽  
Frequency Range ◽  
Lumped Mass ◽  
Coupled Equations ◽  
Piezoelectric Energy ◽  
Electrical Power Output ◽  
Tip Mass

In this paper we present an analytical investigation of a nonlinear energy harvester device. The device is composed of a cantilever beam partially covered by piezoelectric ceramics in a bimorph configuration with a magnetic lumped mass attached to the beam’s free end. The model accounts for the nonlinearity coming from the piezoelectric constitutive equations in addition to the nonlinear effect arising from the magnetic field generated by the magnetic properties of the tip mass and additional magnetic sources in the vicinity of the beam. The electromechanical coupled equations are solved numerically through the initial value problems for ordinary differential equations. The electrical power output is calculated by varying the amplitude of the base acceleration, the distance between the magnets and the load resistor. The stability of the system is also investigated. From the numerical results it is found that the influence of the parameters investigated in the frequency range of operation of the device and the nonlinear effects present on the device energy harvester extend the useful frequency range of these.

Energy Harvesting From Heartbeat Using Piezoelectric Beams With Fan-Folded Configuration and Added Tip Mass

2015 ◽  
Author(s):  
M. H. Ansari ◽  
M. Amin Karami
Keyword(s):  
Natural Frequency ◽  
Energy Harvester ◽  
Mode Shapes ◽  
Mechanical Coupling ◽  
Energy Harvesters ◽  
Piezoelectric Energy ◽  
Power Frequency ◽  
Tip Mass ◽  
Multi Mode ◽  
Very High

A fan-folded piezoelectric energy harvester is designed to generate electricity using heartbeat vibrations. This energy harvester consists of several bimorph beams stacked on top of each other making a fan-folded shape. Each beam has a brass substrate and two piezoelectric patches attached on both sides of it. These beams are connected to each other by rigid beams. One end of the device is clamped to the wall and the other end is free to vibrate. A tip mass is placed at the free end to enhance the output power of the device and reduce the natural frequency of the system. High natural frequency is one major concern about the microscaled energy harvesters. The size for this energy harvester is 1 cm by 1 cm by 1 cm, which makes the natural frequency very high. By utilizing the fan-folded geometry and adding tip mass and link mass to the configuration, this natural frequency is reduced to the desired range. The generated electricity can be used to power up a pacemaker. If enough electricity is generated, the pacemaker operates without having a battery and the patient does not need to have a surgery every seven to ten years to have the battery replaced. The power needed for a pacemaker to operate is about 1 microwatt. In this paper, the natural frequencies and mode shapes of fan-folded energy harvesters with added tip mass and link mass are analytically derived. The electro-mechanical coupling has been included in the model and the expression for the multi-mode power frequency response function is calculated.

Study the Effect of Tapering on the Nonlinear Behavior of an Exponentially Varying Width Piezoelectric Energy Harvester

2018 ◽  
Vol 140 (6) ◽  
Author(s):  
H. Salmani ◽  
G. H. Rahimi
Keyword(s):  
Energy Harvester ◽  
Multiple Scales ◽  
Method Of Multiple Scales ◽  
Equations Of Motion ◽  
Nonlinear Behavior ◽  
High Amplitude ◽  
Mode Shapes ◽  
Geometric Nonlinearities ◽  
Coupled Equations ◽  
Piezoelectric Energy

It has been shown that exponentially tapering the width of a vibration-based piezoelectric energy harvester will result in increasing electric power per mass in a specified frequency. In this paper, a nonlinear solution of an exponentially decreasing width piezoelectric energy harvester is presented. Piezoelectric, inertial, and geometric nonlinearities are included in the presented model, while the exponentially tapered piezoelectric beam's mass normalized mode shapes are utilized in Galerkin discretization. The developed nonlinear coupled equations of motion are solved using method of multiple scales (MMS), and the steady states results are verified by experiment in high amplitude excitation. Finally, the exponentially tapering parameter effect is studied, and it is concluded that the voltage per mass of the energy harvester is improved by tapering at high exciting acceleration amplitudes.

scholarly journals Analysis of a Cantilevered Piezoelectric Energy Harvester in Different Orientations for Rotational Motion

Sensors ◽  
2020 ◽  
Vol 20 (4) ◽  
pp. 1206 ◽  
Author(s):  
Wei-Jiun Su ◽  
Jia-Han Lin ◽  
Wei-Chang Li
Keyword(s):  
Theoretical Model ◽  
Resonant Frequency ◽  
Rotational Motion ◽  
Axial Load ◽  
Energy Harvester ◽  
Excitation Frequency ◽  
Experimental Studies ◽  
Piezoelectric Energy ◽  
Piezoelectric Cantilever ◽  
Tip Mass

This paper investigates a piezoelectric energy harvester that consists of a piezoelectric cantilever and a tip mass for horizontal rotational motion. Rotational motion results in centrifugal force, which causes the axial load on the beam and alters the resonant frequency of the system. The piezoelectric energy harvester is installed on a rotational hub in three orientations—inward, outward, and tilted configurations—to examine their influence on the performance of the harvester. The theoretical model of the piezoelectric energy harvester is developed to explain the dynamics of the system and experiments are conducted to validate the model. Theoretical and experimental studies are presented with various tilt angles and distances between the harvester and the rotating center. The results show that the installation distance and the tilt angle can be used to adjust the resonant frequency of the system to match the excitation frequency.

Optimization of energy harvesting based on the uniform deformation of piezoelectric ceramic

2016 ◽  
Vol 09 (05) ◽  
pp. 1650069 ◽  
Author(s):  
Yaoze Liu ◽  
Tongqing Yang ◽  
Fangming Shu
Keyword(s):  
Energy Harvesting ◽  
Power Output ◽  
Piezoelectric Ceramic ◽  
Energy Harvester ◽  
Optimization Method ◽  
Piezoelectric Energy ◽  
Bonding Area ◽  
Almost All ◽  
Matching Load ◽  
Tip Mass

Since the piezoelectric properties were used for energy harvesting, almost all forms of energy harvester needs to be bonded with a mass block to achieve pre-stress. In this article, disc type piezoelectric energy harvester is chosen as the research object and the relationship between mass bonding area and power output is studied. It is found that if the bonding area is changed as curved, which is usually complanate in previous studies, the deformation of the circular piezoelectric ceramic is more uniform and the power output is enhanced. In order to test the change of the deformation, we spray several homocentric annular electrodes on the surface of a piece of bare piezoelectric ceramic and the output of each electrode is tested. Through this optimization method, the power output is enhanced to more than 11[Formula: see text]mW for a matching load about 24[Formula: see text]k[Formula: see text] and a tip mass of 30[Formula: see text]g at its resonant frequency of 139[Formula: see text]Hz.

Dynamics of Vibration Energy Harvester Governed by Gravity and Magnetic Force in a Rotating Wind Turbine Blade

2018 ◽  
Author(s):  
Saman Nezami ◽  
HyunJun Jung ◽  
Myung Kyun Sung ◽  
Soobum Lee
Keyword(s):  
Angular Velocity ◽  
Wind Turbine ◽  
Magnetic Force ◽  
Energy Harvester ◽  
Turbine Blades ◽  
Wind Turbine Blades ◽  
Vibration Energy Harvester ◽  
Coupled Equations ◽  
Piezoelectric Energy ◽  
Gravity And Magnetic

This paper presents mathematical modeling of an energy harvester (EH) for a wireless structure health monitoring (SHM) system in wind turbine blades. The harvester consists of a piezoelectric energy harvester (PEH) beam, a gravity-induced disk, and magnets attached to both the beam and the disk. An electromechanical model of the proposed EH is developed using the energy method with repelling magnetic force considered. The three coupled equations — the motion of the disk, the vibration of the beam, and the voltage output — are derived and solved using ODE45 in MATLAB software. The result showed the blade rotation speed affects the output angular velocity of disk and the output PEH voltage. That is, as the blade speed increases, the disk angular velocity becomes nonlinear and chaotic which is more beneficial to generate larger power.

Nonlinear Piezoelectric Energy Harvester with Ball Tip Mass

2018 ◽  
Vol 277 ◽  
pp. 124-133 ◽  
Author(s):  
Jung Hwan Ahn ◽  
Won Seop Hwang ◽  
Sinwoo Jeong ◽  
Jae Yong Cho ◽  
Seong Do Hong ◽  
...  
Keyword(s):  
Energy Harvester ◽  
Piezoelectric Energy ◽  
Tip Mass
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