Piezoelectric energy harvesting solutions

This paper reviews the state of the art in piezoelectric energy harvesting. It presents the basics of piezoelectricity and discusses materials choice. The work places emphasis on material operating modes and device configurations, from resonant to non-resonant devices and also to rotational solutions. The reviewed literature is compared based on power density and bandwidth. Lastly, the question of power conversion is addressed by reviewing various circuit solutions

Conceptual design of harvesting energy system for road application

Energy harvesting becomes more and more important in our life. It refers to the practice of acquiring energy from the environment which would be otherwise wasted and converting it into usable electric energy. For this, every kind of energy can be exploited such as solar, wind or strain and kinetic energy. The idea is to propose a conceptual design that will carry out a suitable energy harvesting conversion to be applied for road application. Harvesting energy using piezoelectric generators has been chosen for this project. The project conduct a simulation analysis using a piezoelectric generator based on a model by S Roundy and P K Wright. The data used from a 15 mm x 3.2 mm x 0.14 mm single layer piezoelectric bending element which produce 0.95mW with a 1.727e6 Nm of input stress. The simulation is done using MATLAB-Simulink-SimPowerSystems which also tested with others value by Luigi Pinna et al.. Piezoelectric generator can be one of the green solutions for sustainable development in energy generation

Transmissive Labyrinthine Acoustic Metamaterial‐Based Holography for Extraordinary Energy Harvesting

Conventional energy sources are continuously depleting, and the world is actively seeking new green and efficient energy solutions. Enormous amounts of acoustic energy are dissipated daily, but the low intensity and limited efficiency of current harvesting techniques are preventing its adoption as a ubiquitous method of power generation. Herein, a strategic solution to increase acoustic energy harvesting efficiency using a specially designed metamaterial is implemented. A scalable transmissive labyrinthine acoustic metamaterial (LAM) is designed, developed, and employed to maximize ultrasound (40 kHz) capture over its large surface area (>27 k mm2), which is focused onto a piezoelectric film (78.6 mm2), thus magnifying incident sound pressure by 13.6 times. Three different piezoelectric films – two commercial and one lab-made nanocomposite film are tested with LAM in the acoustic energy harvesting system. An extraordinary voltage gain of 157–173% and a maximum power gain of 272% using the LAM compared to the case without the LAM are achieved. Multipoint focusing using holographic techniques, showcasing acoustic patterning to allow on-demand simultaneous harvesting in separate locations, is demonstrated. Our versatile approach for high-intensity acoustic energy harvesting opens future opportunities to exploit sound energy as a resource to contribute toward global sustainability

A Piezoelectric Device for Measurement and Power Harvesting Applications

Com o apoio RAADRI.With the fast growth of wireless communications between nodes/sensor units, devices installed in remote places require power energy supply solutions to assure their functionally and data communication capabilities. For these applications energy harvesting takes place as a good solution, to increase the availability of energy, in opposition to the conventional systems of energy supply. Regenerative energy sources like thermoelectric, magnetic, piezoelectric, and/or renewable sources such as photovoltaic, wind, among others, allowed the development of different powering solutions for sensor units. The purpose of this work is to characterize a piezoelectric device to measure and capture mechanical vibrations from equipments, structures and piping vibrations, as well as from other sources. The study is carried out taking into account the power supply capabilities of piezoelectric devices as a function of the amplitude and frequency of the vibration stimulus, as well as, the electrical characteristics of the load circuit

Energy harvesting from earthquake for vibration-powered wireless sensors

Wireless sensor networks can facilitate the acquisition of useful data for the assessment and retrofitting of existing structures and infrastructures. In this perspective, recent studies have presented numerical and experimental results about self-powered wireless nodes for structural monitoring applications in the event of earthquake, wherein the energy is scavenged from seismic accelerations. A general computational approach for the analysis and design of energy harvesters under seismic loading, however, has not yet been presented. Therefore, this paper proposes a rational method that relies on the random vibrations theory for the electromechanical analysis of piezoelectric energy harvesters under seismic ground motion. In doing so, the ground acceleration is simulated by means of the Clough-Penzien filter. The considered piezoelectric harvester is a cantilever bimorph modeled as Euler-Bernoulli beam with concentrated mass at the free-end, and its global behavior is approximated by the dynamic response of the fundamental vibration mode only (which is tuned with the dominant frequency of the site soil). Once the Lyapunov equation of the coupled electromechanical problem has been formulated, mean and standard deviation of the generated electric energy are calculated. Numerical results for a cantilever bimorph which piezoelectric layers made of electrospun PVDF nanofibers are discussed in order to understand issues and perspectives about the use of wireless sensor nodes powered by earthquakes. A smart monitoring strategy for the experimental assessment of structures in areas struck by seismic events is finally illustrated

Power Control Optimization of an Underwater Piezoelectric Energy Harvester

Over the past few years, it has been established that vibration energy harvesters with intentionally designed components can be used for frequency bandwidth enhancement under excitation for sufficiently high vibration amplitudes. Pipelines are often necessary means of transporting important resources such as water, gas, and oil. A self-powered wireless sensor network could be a sustainable alternative for in-pipe monitoring applications. A new control algorithm has been developed and implemented into an underwater energy harvester. Firstly, a computational study of a piezoelectric energy harvester for underwater applications has been studied for using the kinetic energy of water flow at four different Reynolds numbers Re = 3000, 6000, 9000, and 12,000. The device consists of a piezoelectric beam assembled to an oscillating cylinder inside the water of pipes from 2 to 5 inches in diameter. Therefore, unsteady simulations have been performed to study the dynamic forces under different water speeds. Secondly, a new control law strategy based on the computational results has been developed to extract as much energy as possible from the energy harvester. The results show that the harvester can efficiently extract the power from the kinetic energy of the fluid. The maximum power output is 996.25 mu W and corresponds to the case with Re = 12,000.The funding from the Government of the Basque Country and the University of the Basque Country UPV/EHU through the SAIOTEK (S-PE11UN112) and EHU12/26 research programs, respectively, is gratefully acknowledged. The authors are very grateful to SGIker of UPV/EHU and European funding (ERDF and ESF) for providing technical and human

Development of piezoelectric harvesters with integrated trimming devices

Piezoelectric cantilever harvesters have a large power output at their natural frequency, but in some applications the frequency of ambient vibrations is different fromthe harvester\u2019s frequency and/or ambient vibrations are periodicwith some harmonic components. To copewith these operating conditions harvesters with integrated trimming devices (ITDs) are proposed. Some prototypes are developed with the aid of an analytical model and tested with an impulsive method. Results show that a small trimming device can lower the main resonance frequency of a piezoelectric harvester of the same extent as a larger tip mass and, moreover, it generates at high frequency a second resonance peak. A multi-physics numerical finite element (FE) model is developed for predicting the generated power and for performing a stress-strain analysis of harvesters with ITDs. The numerical model is validated on the basis of the experimental results. Several configurations of ITDs are conceived and studied. Numerical results show that the harvesters with ITDs are able to generate relevant power at two frequencies, owing to the particular shape of the modes of vibration. The stress in the harvesters with ITDs is smaller than the stress in the harvester with a tip mass trimmed to the same frequency

Design and analytical evaluation of an impact-based four-point bending configuration for piezoelectric energy harvesting

Aiming toward improved energy conversion in piezoelectric energy harvesters, this study investigates four-point bending (FPB) energy harvesters (FPB-EH) to explore their prominent features and characteristics. The FPB configuration innovatively extends energy harvesting capabilities relative to conventional cantilever beams. The FPB-EH comprises a composite piezoelectric beam that rests on two supports of a fixed clamp, excited by contact force applied at two contact lines on a moving clamp. A comprehensive analytical electromechanical model for the vibrating energy harvester is presented with unique modeling features, including multi-beam sections and multi-mode-shape functions. Solutions of the analytical model are presented for a wide range of contact force types, including steady-state solutions for harmonic forces, impact forces, periodic and non-periodic arbitrary forces. This comprehensive model progresses the state-of-the-art piezoelectric modeling knowledge and is readily applicable to various energy harvesting configurations. The model is validated against experimental results and finite element analysis. Next, a parametric study was performed to evaluate the effects of various FPB characteristics, including the fixed and moving clamp spans, the waveform, and the period-time of contact force. The results indicate that the FPB configuration can enhance energy conversion efficiency and normalized output energy by factors of over 3 and 6, respectively. Finally, guidance is given for selecting between cantilever and four-point bending configurations

A two-step hybrid approach for modeling the nonlinear dynamic response of piezoelectric energy harvesters

An effective hybrid computational framework is described here in order to assess the nonlinear dynamic response of piezoelectric energy harvesting devices. The proposed strategy basically consists of two steps. First, fully coupled multiphysics finite element (FE) analyses are performed to evaluate the nonlinear static response of the device. An enhanced reduced-order model is then derived, where the global dynamic response is formulated in the state-space using lumped coefficients enriched with the information derived from the FE simulations. The electromechanical response of piezoelectric beams under forced vibrations is studied by means of the proposed approach, which is also validated by comparing numerical predictions with some experimental results. Such numerical and experimental investigations have been carried out with the main aim of studying the influence of material and geometrical parameters on the global nonlinear response. The advantage of the presented approach is that the overall computational and experimental efforts are significantly reduced while preserving a satisfactory accuracy in the assessment of the global behavior