scholarly journals A New Method to Perform Direct Efficiency Measurement and Power Flow Analysis in Vibration Energy Harvesters

Sensors ◽  
2021 ◽  
Vol 21 (7) ◽  
pp. 2388
Author(s):  
Jan Kunz ◽  
Jiri Fialka ◽  
Stanislav Pikula ◽  
Petr Benes ◽  
Jakub Krejci ◽  
...  
Keyword(s):  
Lead Zirconate Titanate ◽  
Polyvinylidene Fluoride ◽  
Power Flow ◽  
Flow Analysis ◽  
Lead Zirconate ◽  
Input Power ◽  
Mechanical Power ◽  
Vibration Source ◽  
Energy Harvesters ◽  
The Difference

Measuring the efficiency of piezo energy harvesters (PEHs) according to the definition constitutes a challenging task. The power consumption is often established in a simplified manner, by ignoring the mechanical losses and focusing exclusively on the mechanical power of the PEH. Generally, the input power is calculated from the PEH’s parameters. To improve the procedure, we have designed a method exploiting a measurement system that can directly establish the definition-based efficiency for different vibration amplitudes, frequencies, and resistance loads. Importantly, the parameters of the PEH need not be known. The input power is determined from the vibration source; therefore, the method is suitable for comparing different types of PEHs. The novel system exhibits a combined absolute uncertainty of less than 0.5% and allows quantifying the losses. The approach was tested with two commercially available PEHs, namely, a lead zirconate titanate (PZT) MIDE PPA-1011 and a polyvinylidene fluoride (PVDF) TE LDTM-028K. To facilitate comparison with the proposed efficiency, we calculated and measured the quantity also by using one of the standard options (simplified efficiency). The standard concept yields higher values, especially in PVDFs. The difference arises from the device’s low stiffness, which produces high displacement that is proportional to the losses. Simultaneously, the insufficient stiffness markedly reduces the PEH’s mechanical power. This effect cannot be detected via the standard techniques. We identified the main sources of loss in the damping of the movement by the surrounding air and thermal losses. The latter source is caused by internal and interlayer friction.

Energy Harvesting From PZT Nanofibers

2007 ◽  
Vol 1034 ◽  
Author(s):  
Yong Shi ◽  
Yong Shi
Keyword(s):  
Energy Harvesting ◽  
Dynamic Loading ◽  
Lead Zirconate Titanate ◽  
Output Voltage ◽  
Mechanical Vibration ◽  
Titanium Substrate ◽  
Average Diameter ◽  
Lead Zirconate ◽  
Electrospinning Process ◽  
Vibration Source

AbstractIn this paper, we demonstrated that Lead Zirconate Titanate (PZT) nanofibers can be used to harvest energy from dynamic loading and mechanical vibration. PZT nanofibers were fabricated by electrospinning process. SEM image of PZT nanofibers has shown that the average diameter of these fibers is about 150nm, which can be tuned from 50nm to 200 nm by varying the composition and viscosity of the precursor for electrospining. Titanium substrate with ZrO2 layer was used to collect the PZT nanofibers for the demonstration of energy harvesting from dynamic loading. The largest output voltage is 170mV under 0.5% strain; the frequency of the output voltage is the same as that of the input loading. Silicon substrate with trenches was used to collect the nanofibers for energy harvesting from vibration. The output voltage generated from 150Hz sinusoid vibration source has peak voltages of 64.9mV and -95.9mV. These experimental results suggest that PZT nanofibers have great potentials for energy harvesting from environments and being used as nanogenerators. Further study is under the way to optimize the design and improve the efficiency.

scholarly journals Piezoelectric Properties of Lead Zirconate Titanate Ceramics at Low and High Temperatures

2020 ◽  
Author(s):  
Mitsuhiro Okayasu ◽  
Masakazu Okawa
Keyword(s):  
Thermal Stress ◽  
Lead Zirconate Titanate ◽  
Domain Switching ◽  
Low Voltage ◽  
Lead Zirconate ◽  
Negative Voltage ◽  
Zirconate Titanate ◽  
Positive Voltage ◽  
Warming Rate ◽  
The Difference

Abstract The material properties and damage characteristics of lead zirconate titanate (PZT) ceramics were investigated at various temperatures (–190 °C to 180 °C). A positive voltage was obtained when the sample was cooled from 20 °C to –190 °C, while a negative voltage was obtained when the sample was warmed from –190 °C to 180 °C. The difference between the positive and negative values depended on the thermal stress. Compressive stress generated a more positive voltage in the cooling process, while tensile stress led to a more negative voltage in the warming process). The voltage values also depended on the cooling (or warming) rate of the sample, e.g., the greater the cooling (or warming) rate, the greater the voltage. When cyclic loading was conducted mechanically at –190 °C, the voltage reduced, but it was recovered after warming to 20 °C. Damage of the PZT ceramic (90° domain switching) was detected when the sample was cooled to –190 °C. This was due to the high thermal stress, resulting in a low voltage.

Predicting Effective Electromechanical Properties of Pb-Free Polymer Composite Using Finite Element Method

2020 ◽  
Vol 978 ◽  
pp. 337-343
Author(s):  
Neelam Mishra ◽  
Chaitanya Shah ◽  
Kaushik Das
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Polymer Composite ◽  
Lead Zirconate Titanate ◽  
Polyvinylidene Fluoride ◽  
Volume Fraction ◽  
Lead Zirconate ◽  
Sensors And Actuators ◽  
Micro Particles ◽  
Element Method

Polyvinylidene fluoride (PVDF) – Lead Zirconate Titanate (PZT) is a polymer composite that is becoming increasingly popular in micro-scale sensors and actuators because of its unique properties such as high flexibility, low density and high piezoelectric constants. However, lead-based piezoceramics, despite their superior properties, are toxic and are known to damage the environment, and as such a conscientious effort is being made by the scientific community towards replacing lead-containing piezoceramics with environmentally-friendlier and lead-free piezoceramics. Barium Titanate (BaTiO3) is one such piezoceramics that is widely studied today to be a potential replacement of PZT in many applications. As such, in this work, effort has been made to predict the effective mechanical, dielectric and piezoelectric properties of PVDF-BaTiO3 composite system using Finite Element Method (FEM). Kinematic Uniform Boundary Conditions (Displacement and Voltage) are used for this analysis. For evaluation of the effective material constants of the composite, several types of representative volume elements are considered. The effects of volume fraction, effect of the size of the micro-particles i.e. mono-modal versus multi-modal size distribution, effect of periodic versus quasi-random distribution of microparticles in the matrix, the effect of clustering of the particles, effect of orientation of the microparticles i.e. unidirectional or randomly oriented are discussed. Finally, a comparison of properties between PVDF-PZT and PVDF-BaTiO3 is made, so as to see whether PVDF-BaTiO3 can be a potential replacement for PVDF-PZT composite.

LTCC Piezoelectric Transducer for Energy Harvesting

2015 ◽  
Vol 2015 (CICMT) ◽  
pp. 000105-000111
Author(s):  
Arkadiusz P. Dabrowski ◽  
Slawomir Owczarzak ◽  
Henryk Roguszczak ◽  
Leszek J. Golonka
Keyword(s):  
Energy Harvesting ◽  
Output Power ◽  
Lead Zirconate Titanate ◽  
Piezoelectric Transducer ◽  
Lead Zirconate ◽  
Mean Power ◽  
Optimum Load ◽  
Resonance Frequencies ◽  
The Mean ◽  
The Difference

In this paper, design, technology and properties of multi cantilever transducer for energy harvesting application were described. The piezoelectric transducer was made in LTCC (Low Temperature Cofired Ceramics) technology using PZT (Lead Zirconate-Titanate) based tape. In such devices the highest power can be reached at resonance frequencies of the cantilevers. Eight bimorph transducers with lengths corresponding to 33, 50, 58, 66, 75, 82, 91 and 100 Hz resonant frequency, were designed. The transducers were polarized in serial or parallel configuration. To avoid voltage reduction in the system of a few piezoelectric bimorphs, rectifiers were applied for each cantilever. Transducers had optimum resistance in ranges of 60–140 kΩ and 300–600 kΩ for bimorphs poled in parallel and serial configuration, respectively. The mean output power under sinusoidal excitation with 20 μm vibration amplitude calculated from all maxima at resonant frequencies for optimum load, were equal to 10.3 μW and 12.4μW for parallel and serial configurations with rectifier. Without rectifier the values were equal to 18.2 μW for both the transducers. In case of mean output power, the difference between both the transducers was not really significant, however at higher frequency the maximum power was higher for serial configuration. Besides, the output voltage obtained in serial bimorph was higher than in parallel one. The mean power density for all the resonant peaks measured at 0.41 g was equal to 210 μW/cm3/g and 360 μW/cm3/g with and without rectifier, respectively.

Nonlinear Input Power Flow Analysis of a Plate with a Breathing Crack

2014 ◽  
Vol 638-640 ◽  
pp. 163-167
Author(s):  
Zhong Hao Pang ◽  
Xiang Zhu ◽  
Tian Yun Li ◽  
Ling Zhang
Keyword(s):  
Nonlinear Dynamic ◽  
Power Flow ◽  
Damage Identification ◽  
Flow Analysis ◽  
Nonlinear Dynamic Analysis ◽  
Nonlinear Behavior ◽  
Input Power ◽  
Breathing Crack ◽  
Engineering Structures ◽  
Power Characteristics

Plates are commonly used in engineering structures. However crack is the most common form of damages in the plate structures. The crack in the plate will open and close during vibrational cycle, making the cracked structure with nonlinear dynamic characteristics. Based on vibrational power flow theory, the nonlinear dynamic analysis of a plate structure is carried out. The contact elements are used to simulate the nonlinear behavior of the breathing crack. Aiming to study the input power characteristics and the super harmonic resonance of a breathing cracked plate which is under the resonant excitation. By the finite element calculation, the structural input power curve is analyzed, which provides a theoretical basis for the damage identification of cracked structures.

Vibrational Power Flow Analysis of Stiffened Plate and Shell Structures

2011 ◽  
Vol 66-68 ◽  
pp. 1897-1901 ◽  
Author(s):  
Xiang Zhu ◽  
Gong Yu Xiao ◽  
Tian Yun Li ◽  
Xiao Fang Hu
Keyword(s):  
Cylindrical Shell ◽  
Power Flow ◽  
Flow Analysis ◽  
Flow Characteristics ◽  
Input Power ◽  
Shell Structures ◽  
Stiffened Plate ◽  
Simply Supported ◽  
Plate And Shell ◽  
Flow Vectors

In this paper, the vibration and power flow characteristics of stiffened plate and cylindrical shell structures are investigated by using finite element method. The power flow formulas of basic shell structural elements are given at first. Then a simply supported plate and stiffened plate’s input power flow characteristics and power flow vectors are investigated. The effects of stiffeners in plates are discussed. For a simply supported cylindrical shell, the influence of the structural damping, viscous damper and stiffeners on the cylindrical shell’s input power flow characteristics and propagated power flow characteristics are discussed in detail. The power flow vectors are visualized to reveal the distribution of energy in the shell structures. Some useful conclusions are drown and helpful for the vibration control of plate and shell structures.

Longitudinal Loop Power Flow Analysis on a 4x4 Transmission Vehicle Taking into Consideration the Running Track Type

2013 ◽  
Vol 837 ◽  
pp. 483-488
Author(s):  
Marian Truta ◽  
Marin Marinescu ◽  
Radu Vilau ◽  
Octavian Fieraru
Keyword(s):  
Power Flow ◽  
Positive Impact ◽  
Flow Analysis ◽  
Rolling Process ◽  
Traction Control ◽  
Vehicle Type ◽  
Control Devices ◽  
The Difference ◽  
Set Up ◽  
The Mathematical Model

This paper presents an analysis for the longitudinal loop power flow of a 4x4 driven vehicle type taking into consideration the influence of the running track. The goal set up by this paper is to experimentally verify the existence of a certain dependency between the longitudinal loop power flow and the type of the running track the vehicle is moving on. Such a determination could have a positive impact by optimizing the vehicle exploitation or even its modernization. The loop power-flow is the result of the self-generated torque within the automobiles transmission, which is, at its turn, a consequence of cinematic misfits during the rolling process of the wheels. The mathematical model stated in this paper is confirmed by the means of multiple tests developed in real conditions. In order to carry out experimental research we used an all-driven, wheeled military APC, reconnaissance vehicle. The longitudinal power flow was determined with the vehicle moving in straight motion but having different rolling radius between the axles. The rolling radii of the wheels of the same axle were the same. The difference between the rolling radii was set to 0.03 m then to 0.05 m. The vehicle traveled on tarmac then on grass. The transmission of a vehicle that is susceptible in generating loop power-flow can be updated to decrease and technically eliminate it. Prior to such an update, a thorough analysis of the transmission working regimes should be performed, especially of those regimes that are most probable to generate loop power-flow. The paper presents the equipment used to perform the measurements and the way it was mounted on the vehicle. It also presents the values for the longitudinal power flow, recorded for both rolling radii differences. The results are presented in graphic display. Eventually, the paper presents the longitudinal power flow taking into account the difference between the rolling radii and its dependency towards the running tracks type. This study can be extended to all the 4WD automobiles, which have special traction control devices. The results obtained were processed in order to underline the power loops within the longitudinal transmission. Thus, important and interesting results could be drawn.

Local ferroelectric properties in polyvinylidene fluoride/barium lead zirconate titanate nanocomposites: Interface effect

2013 ◽  
Vol 114 (14) ◽  
pp. 144102 ◽  
Author(s):  
M. V. Silibin ◽  
A. V. Solnyshkin ◽  
D. A. Kiselev ◽  
A. N. Morozovska ◽  
E. A. Eliseev ◽  
...  
Keyword(s):  
Lead Zirconate Titanate ◽  
Polyvinylidene Fluoride ◽  
Ferroelectric Properties ◽  
Lead Zirconate ◽  
Interface Effect ◽  
Zirconate Titanate
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