Vibration Energy Harvesting Research Articles

Self-powered synchronous asymmetric voltage flip and charge extraction technique for piezoelectric energy harvesting

Abstract This paper presents a nonlinear interface circuit for piezoelectric vibration energy harvester (PEH) with Synchronous Asymmetric Voltage Flipping and Charge Extraction process, denoted as SAFCE. SAFCE flips the PEH voltage polarity at positive peak and completely extracting charge at negative peak through LC resonance. The harvested power is independent of load. In theory, the harvested power is 200 % of SECE and 780 % of best impedance-matched SEH due to the energy injection mechanism, which enhances the electromechanical coupling coefficient of PEH. Moreover, a self-powered SAFCE circuit without rectifier bridge is designed, which reduces power consumption and eliminates the need for external power sources. Experimental measurements are carried out to compare with SEH and SECE circuits under the condition of either constant displacement magnitude (0.5 mm) or constant external excitation acceleration (10 m/s2). The experimental results indicate that the power harvested by the SAFCE technique increased by 171 % compared with the SECE method and by 381 % compared with the best impedance-matched SEH method under the same conditions.

Nonlinear energy harvesting system with multiple stability

The nonlinear energy harvesting systems of the forced vibration with an electron-mechanical coupling are widely used to capture ambient vibration energy and convert mechanical energy into electrical energy. However, the nonlinear response mechanism of the friction induced vibration (FIV) energy harvesting system with multiple stability and stick-slip motion is still unclear. In the current paper, a novel nonlinear energy harvesting model with multiple stability of single-, double- and triple-well potential is proposed based on V-shaped structure spring and the belt conveying system. The dynamic equations for the energy harvesting system with multiple stability and self-excited friction are established by using Euler-Lagrangian equations. Secondly, the static characteristics of the nonlinear restoring force, the friction force, and the potential energy surfaces are obtained to show the nonlinear stiffness, multiple equilibrium points, discontinuous behaviors and multiple well responses. Then, the equilibrium surface of bifurcation sets for the autonomous system is given to show the third-order quasi zero stiffness (QZS3), fifth-order quasi zero stiffness (QZS5), double well (DW) and triple well (TW). The co-dimension bifurcation sets of the self-excited vibration system are analyzed and the corresponding phase portraits for the coexistent of multiple limit cycles are obtained. Furthermore, the analytical formula of amplitude frequency response of the approximated system are obtained by the complex harmonic method. The response amplitudes of charge, current, voltage and power of the forced electron-mechanical coupled vibration system for QZS3, QZS5, DW and TW are analyzed by using the numerically solution. Finally, a prototype of FIV energy harvesting system is manufactured and the experimental system is setup. The experimental works of static restoring forces, damping forcse and the electrical outputs are well agreeable with the numerical results, which testified the proposed FIV energy harvesting model.

Nonlinear vibration energy harvesting via parametric excitation: Snap-through with time-varying potential wells

This study introduces a novel method to improve snap-through transitions in a parametrically excited cantilever-based energy harvester featuring repulsive magnetic coupling. The aim is to enhance the efficiency of a piezoelectric energy harvester while broadening its operational frequency range. The design incorporates an oscillating substructure that magnetically interacts with the beam, promoting easier transitions. Additionally, this setup capitalizes on the resonant energy of the substructure to optimize energy capture. This study addresses a previously unexplored limitation in the directly excited counterpart by optimizing the use of substructure’s resonant energy to significantly improve the energy harvesting device’s efficiency. We present a theoretical model based on the Hamilton principle, which is solved numerically. Comprehensive experimental studies are conducted to validate the theoretical results, showing a strong correlation between the experimental outcomes and theoretical predictions. The findings indicate that an oscillating substructure with a tailored natural frequency close to twice that of the parametrically excited piezoelectric beam can induce time-varying potential wells to facilitate snap-through transitions. Despite the damping coefficient of the piezoelectric beam being three times higher than that of its simple beam counterpart, periodic perturbations still effectively expand its instability region. This enlarged instability region, resulting from such perturbations, not only exhibits broadband characteristics but also facilitates efficient energy harvesting at lower excitation levels.

Wind-induced vibration energy harvesters under base excitation: Analytical and numerical analysis

In this paper, analytical analysis of a wind-induced vibration energy harvester used for the bacterial disinfection of water is mainly considered. The complexification-averaging (CA) method is utilized to analytically calculate the results of the harvester, the model equations of the harvester satisfied are reduced into a set of complex variable equations. The relationship between the displacement amplitude and voltage amplitude is derived under the steady-state case. The amplitudes and phases of both the displacement and voltage are obtained. The analytical solutions of the harvester are then verified by direct numerical simulation. The response mechanism under different parameters is discussed. The frequency island and multi-valued phenomena are found. Meanwhile, it is found that a higher wind speed corresponds to a larger displacement amplitude and voltage. In addition, the RMS voltage and average power are studied. Both have the same variation rules under different excitation amplitudes. Under the same coupling coefficient, load resistance and piezoelectric patch capacitance, the lower the frequency, the easier it is to obtain the larger voltage output. However, the load resistance has the opposite effect on both of them. Finally, to obtain maximum output in a wider frequency region, the optimization and choice of the parameters is studied, and the critical boundary can be identified.

Enhancing production of hydrogen and simultaneous degradation of ciprofloxacin over Sn doped SrTiO3 piezocatalyst

The combination of hydrogen production from water and degradation of organic pollutants into a single reaction system is an attractive and promising solution for renewable energy generation and wastewater treatment. Herein, the piezocatalytic production of hydrogen coupled with simultaneous piezocatalytic degradation of organic antibiotic (ciprofloxacin) was successfully achieved using Sn doped SrTiO3 as the highly efficient and robust piezocatalyst through harvesting vibration energy. Results showed that 5 mol% Sn doped SrTiO3 (SrSn0.05Ti0.95O3) showed the highest piezocatalytic production rate of hydrogen (101.46 μmol g−1h−1) in water. And SrSn0.05Ti0.95O3 also exhibited remarkable piezocatalytic activity in solution containing ciprofloxacin with 151.03 μmol g−1h−1 of H2 evolution rate and 77.5 % of ciprofloxacin degradation efficiency within 60 min. In this process, the doping of Sn largely enlarged the distorted structure and conductivity of SrTiO3 to improve the piezocatalytic activity, and the organic ciprofloxacin mainly acted as the electron donors to synergistically improve the reduction process for H2 evolution. This work establishes the relationships between the piezoelectric property and the piezocatalyst structure, and provides an approach of advanced piezocatalytic technology for wastewater treatment and renewable energy generation.

Comprehensive Characterisation of a Low-Frequency-Vibration Energy Harvester.

In this paper, we describe a measurement procedure to fully characterise a novel vibration energy harvester operating in the ultra-low-frequency range. The procedure, which is more thorough than those usually found in the literature, comprises three main stages: modelling, experimental characterisation and parameter identification. Modelling is accomplished in two alternative ways, a physical model (white box) and a mixed one (black box), which model the magnetic interaction via Fourier series. The experimental measurements include not only the input (acceleration)-output (energy) response but also the (internal) dynamic behaviour of the system, making use of a synchronised image processing and signal acquisition system. The identification procedure, based on maximum likelihood, estimates all the relevant parameters to characterise the system to simulate its behaviour and helps to optimise its performance. While the method is custom-designed for a particular harvester, the comprehensive approach and most of its procedures can be applied to similar harvesters.

A multi-node self-powered fault detection system by triboelectric-electromagnetic nanosensors for smart transportation

The harnessing of vibrational energy is becoming increasingly pivotal in the development of intelligent rail transit systems. The integration of emerging technologies such as triboelectric nanogenerators (TENGs), electromagnetic generators (EMGs), or hybrid generators has become crucial for fault detection and energy harvesting in rail transit. This paper introduces a self-powered fault detection system (SPFDS). SPFDS combines multiple compact rotating Triboelectric-Electromagnetic Nanosensor (TENS) nodes with a deep learning-based diagnostic module to transform vibrational energy generated during train operations into electrical power and accurately identifies five distinct train bogie fault conditions. Simulations and experiments have shown that the TENS nodes, with a root mean square power of 0.21 W and a power density of 1595.7 W/m³, can efficiently detect various bogie faults. Additionally, their power output is adequate to support commercial sensors and Bluetooth modules. Through hyperparameter optimization, the diagnostic module utilizing multi-TENS nodes achieves an average diagnostic accuracy of 99.38 % for the five fault modes of freight train bogies. Implementing multiple TENS nodes in SPFDS enhances fault detection accuracy by an average of 32 % compared to a single TENS node, with a peak increase of 128 %. The multi-node TENS configuration and SPFDS's self-powered detection capabilities represent an innovative approach to complex fault detection, significantly contributing to the advancement of vibration energy harvesting and the development of distributed self-powered sensor network technologies for smart transportation.

Electro-Mechanical Coupling Analysis of L-Shaped Three-Dimensional Braided Piezoelectric Composites Vibration Energy Harvester.

In this article, an L-shaped three-dimensional (3D) braided piezoelectric composite energy harvester (BPCEH) is established, which consists of an elastic layer composed of a 3D braided composite, flanked by upper and lower layers of piezoelectric material and two tuning mass blocks. Glass fiber and epoxy resin are used to produce a 3D braided composite. This L-shaped 3D BPCEH is mechanically designable and can be adapted to different work requirements by varying the braided angle of the 3D braided composite layer. The material parameters of 3D braided composites are predicted for different braided angles by means of a representative volume element (RVE). Electro-mechanical coupled vibration equations for the L-shaped 3D BPCEH are established. The impact of braided angles on voltage and power output is discussed in this article. Simulations using finite element method are conducted to analyze the voltage and power output responses at various braided angles. In addition, the effects of the mass of mass block B and the length of the beam on the output performance of the L-shaped 3D BPCEH are analyzed.

A piezo-electromagnetic hybrid multi-directional vibration energy harvester in freight trains

Rail freight systems are widely acknowledged for their operational efficiency across various nations. However, a prevailing limitation lies in the absence of power supply within standard freight wagons, impeding the installation of essential sensors to monitor train operation. This paper provides an innovative solution to this issue, where a novel device is developed to harvest vibration energy from freight trains to power operational condition monitoring sensors. The proposed device integrates a piezoelectric energy harvester with an electromagnetic counterpart, utilizing a spring-mass structure to capture vibration energy and transfer it to cantilever beams through magnetic coupling. A cantilever beam with variable width and a distinctive “checkmark” shape is employed to ensure even stress distribution to enhance piezoelectric material efficiency. The optimal spatial configuration between magnets and coils, as well as inter-magnet spacing, is determined through finite element analysis and empirical testing. Experimental results under the excitation with a frequency of 9.5 Hz and a vertical amplitude of 2 mm show the hybrid harvester can generate a maximum power of 3.276 mW. This hybrid energy harvesting system has the potential to provide dependable power to electronic components, including temperature sensors and accelerometers, crucial for monitoring rail freight train operations.

Low Frequency Vibration Energy Harvesting of Piezoelectric Vibration Systems with an Adjustable Device and Inertial Amplifier Device

Low Frequency Vibration Energy Harvesting of Piezoelectric Vibration Systems with an Adjustable Device and Inertial Amplifier Device

A novel asymmetric tri-stable piezoelectric vibration energy harvester for low-orbit vibration energy harvesting enhancement

This study introduces an innovative asymmetric tri-stable piezoelectric vibration energy harvester (ATPVEH) augmented with an elastic base (EB), aimed at optimizing energy capture from low-orbit vibrations. This design incorporates a uniquely configured asymmetric tri-stable piezoelectric cantilever beam, positioned within a U-shaped block that is further enhanced by an elastic base. A strategically placed spring (kf)–mass (Mf) system, situated between the U-shaped block and the constrained end of the beam, significantly boosts the vertical displacement of the beam during vibrational events. We developed a dynamic model for the ATPVEH+EB utilizing Lagrange’s equations, exploring the impact of various factors—including the asymmetry of the potential well, the stiffness of the elastic base, the mass of the spring–mass system, and the load resistance—on the system’s nonlinear dynamic responses. Our findings indicate that the ATPVEH+EB facilitates more efficient energy harvesting from low-orbit vibrations, demonstrating dual response peaks across its operational frequency spectrum. Notably, the displacement and output voltage amplitudes of the ATPVEH+EB can be enhanced by increasing mf or decreasing kb, whereas the peak output power transitions toward a lower frequency range as the load resistance escalates. Both theoretical analyses and numerical simulations corroborate the ATPVEH+EB’s superior performance in harvesting energy within low-orbit vibrational environments.

The Influence of Different Mass Ratios on Vortex-Induced Vibration Energy Extraction of Four Cylinder Arrays

Currently, there is a growing demand for renewable energy harnessed from fluid dynamics within the oil and gas industry. The surge in demand has propelled electricity to become a vital and irreplaceable form of universal energy worldwide. Vortex-Induced Vibrations (VIV) energy harvesting shows great potential as a technology for capturing energy from flowing bodies of water. The purpose of this research is to investigate the numerical aspect of VIV in rigid circular cylinders with the intention of capturing renewable energy from the sea. The investigation employs a Vortex-Induced Vibration Aquatic Clean Energy (VIVACE) converter to analyze the vibration characteristics of densely packed cylinders featuring varying mass ratios (m*) at both minimum and maximum values. Another purpose of the study is to investigate the effect that m* has on the performance of a VIV converter that is comprised of four cylinders positioned in a staggered pattern. For the purpose of analyzing power conversion in the VIV energy converter model across a wide range of mass ratios (from 2.36 to 12.96), simulations are carried out with a Reynolds number of 82000. The findings indicate that the highest converted power reaches a peak of 7.48 W with a mass ratio of 2.36, whereas a greater mass ratio of 12.96 results in only 4.33. The study highlights the substantial influence of mass ratios on the extraction of power output from VIV. The results essentially offer crucial information about the optimum mass ratio in closed four cylinder arrays to design VIV energy harvesting to produce clean and renewable energy sources.

Potential use of piezoelectric laser-induced vibration energy harvesting in wireless power transmission: Theoretical modelling and simulation

Because of continuous trend in wireless microdevice technology, a novel model of a laser-induced piezoelectric microgenerator within the framework of the non-Fourier heat conduction and nonlocal elasticity theory is proposed in this research. A non-Gaussian profile is considered for the laser source. The Galerkin method and the Laplace transform are employed to discretize and solve the coupled electro-thermo-mechanical equations, respectively. The inverse Laplace transform is numerically calculated to investigate the influences of the resistance load, laser intensity, laser absorption depth, specific heat capacity and thickness of the piezoelectric layer on the voltage response and power output of the microharvester. The obtained results reveal that the performance of the microharvester is dramatically affected by changing these parameters. Also, some optimum design parameters are provided to ensure the best performance of the system. Therefore, the present study can be helpful in analysis, design and optimization of wireless power devices, light-induced actuators and sensors in the future.

Study of vibration suppression and energy harvesting for a Vibration-based Piezoelectric–Electromagnetic energy harvester with nonlinear energy sink

Vibration-based energy harvesting devices are prone to excessive displacement response. The effective vibration suppression is critical to the longevity and safety of energy harvesting systems. In this work, the vibration-based Piezoelectric–Electromagnetic energy harvester with nonlinear energy sink (NES-VBPEEH) is proposed to achieve the dual efficacy goals of vibration suppression and vibration energy harvesting. The electromechanical-coupled distributed governing equations are derived through Hamilton’s principle, Euler’s Bernoulli theory, Gauss’s law and Faraday’s law of electromagnetic induction. The output performances of the degradation model of the NES-VBPEEH are validated by previous work. Parameter analysis indicates that the external resistance of the piezoelectric energy harvester significantly affects the electrical damping of the system and ultimately affects the output response of the NES-VBPEEH. The external resistance and coil turns of the electromagnetic vibration energy harvester can significantly affect the output response of the NES-VBPEEH. The output power of both types of energy harvesters is maximized with respect to the resistance and the coil turns. The output response of the NES-VBPEEH exhibits certain nonlinear characteristics as the external excitation amplitude increases to a certain value. The damping and nonlinear stiffness of the NES can significantly affect the output power of the NES-VBPEEH, and appropriate parameter selection can help to achieve the dual efficacy goals of vibration suppression and vibration energy harvesting for the energy harvester.

A pendulum based frequency-up conversion mechanism for vibrational energy harvesting in low-speed rotary structures

Motivated to run a self-powering monitoring sensor on a wind turbine blade, this paper proposes a pendulum based frequency-up converter that effectively captures a low-speed mechanical rotation into high-frequency vibration of a piezoelectric cantilever beam. A system of governing equations for the proposed concept is developed to describe the motion of the pendulum, the vibration of the beam, and the voltage output of the harvester. Design optimization is performed to improve the power generation performance, and the simulation results are verified experimentally. We demonstrate the improved power density from the proposed concept compared to the disk driven frequency-up converters.

Ribbed elastic metasurface with lateral scalability for flexural wave manipulation

With the goal of engineering applications, the scalability and structural portability of elastic metasurfaces have become significant and attractive. However, most existing elastic metasurfaces cannot be arbitrarily scalable, which will inevitably limit their applications. Here, a novel conceptual design of ribbed elastic metasurfaces (REMs) is proposed for anomalous wavefront manipulation of flexural waves in thin plates. Ribbed subunits, as functional subunits of REMs, are characterized by simple constructions. The phase shift mechanism for the flexural waves across the ribbed subunits is revealed by analyzing the lowest dispersion bands. The analytical model for ribbed subunits is also established based on the equivalent orthotropic plate theory and transfer matrix method (TMM) to accurately predict the phase shift and amplitude of the transmitted waves. In addition, lateral scalability can be observed when the ratio of rib width to subunit width is constant, owing to the constant equivalent bending stiffness. By considering the lateral scalability of subunits, the continuous adjustment of the refraction angle can be perfectly achieved. The deflecting and focusing functionalities of the designed REMs are numerically and experimentally demonstrated. Both simulated and experimental results are consistent with theoretical results. Since ribbed plates are typical load-bearing structures in engineering, our design has broad application prospects, including but not limited to vibration control, energy harvesting, and structural health monitoring.

A self-powered accelerometer with over-range detection for vibration and shock based on triboelectric-electromagnetic mechanism

Accelerometers based on triboelectric nanogenerators (TENGs) have garnered significant interest in recent years. However, many of these devices lack a self-sustained power supply for autonomous wireless operations and a mechanism for over-range detection. Additionally, theoretical investigations on the sensitivity of TENG-based accelerometers are scarce. In this work, a novel self-powered accelerometer for vibration and shock integrating a freestanding triboelectric-layer-based TENG (FT-TENG), two contact-separation TENGs (CS-TENGs) and an electromagnetic generator (EMG) is proposed and then investigated through both numerical simulations and experimental demonstrations. The EMG is used for vibration energy harvesting, exhibiting an impressive power output of 4.11 mW under a vibration acceleration of 12 m/s2. The FT-TENG and the CS-TENGs work for acceleration sensing and over-range detection respectively. Under vibration, the sensitivity and measurement range are related to the frequency of excitation, and the proposed accelerometer has the maximum sensitivity (0.75 V s2/m) at its natural frequency. For shock events, the sensitivity of the accelerometer is dominated by the shock duration in a short-duration range, which is estimated to be 0.12 V s2/m under a shock duration of 0.03 s. This work not only contributes to the understanding of TENGs adopted for sensing but also creates potential applications of triboelectric and electromagnetic energy harvesting and provides a feasible design for autonomous wireless sensor nodes.

Stochastic response and stability analysis of nonlinear vehicle energy-regenerative suspension system with time delay

With the rapid development of new energy vehicles, a novel vehicle energy-regenerative suspension for simultaneous vibration suppression and energy harvesting has become one of the key development directions of the next generation of vehicle design. In order to improve the performance of suspension system, the time-delayed feedback control is applied to the novel suspension system subjected to different external excitation. At the same time, there are few studies related to the stochastic dynamics of nonlinear vehicle energy-regenerative suspension system with time delay. This paper studies stochastic response and stability of nonlinear vehicle energy-regenerative suspension with time-delayed feedback control under the excitation of Gaussian white noise. First of all, a stochastic dynamic model of the nonlinear vehicle energy-regenerative suspension with time delay system is established. Secondly, using the stochastic averaging method based on generalized harmonic function, the steady-state probability density function (PDF) of amplitude is obtained. The accuracy of the presented approach is verified through the comparison of analytical and numerical solutions. In addition, through combining the stochastic averaging method with the Khasminskii method, the top Lyapunov exponent (TLE) of the system is obtained, and then the influence of time delay and system parameters on the asymptotic Lyapunov stability is discussed. Finally, the effects of time delay and system parameters on system performance are also studied.

Active tuned mass damper for a benchmark tall building using an energy-harvesting electromagnetic damper

Among various structural vibration control categories, active control typically provides superior control performance. However, its high energy demand often limits its extensive implementation in large-scale civil structures. Very recently, electromagnetic dampers, which can convert kinetic energy into electrical energy, have emerged as a novel solution for active control with reduced or even zero energy consumption. This study explored the feasibility of an energy-harvesting active tuned mass damper (ATMD) by using an electromagnetic damper for simultaneous vibration suppression and energy harvesting. Numerical simulations were conducted for a full-scale, 76-story benchmark building equipped with the proposed design. The proposed ATMD outperforms the optimised passive counterpart of the same mass, as the former introduces an evident reduction in displacement responses. Furthermore, the proposed ATMD can offer a commensurate control performance to a passive damper with a weight three times heavier. The proposed ATMD also exhibits promising energy-harvesting performance, achieving an average output power at the kilowatt level. The results suggest that electromagnetic devices hold great potential for large-scale applications in civil structures, paving the way for a prosperous future in this field.

Nonlinear Dynamic Response of Galfenol Cantilever Energy Harvester Considering Geometric Nonlinear with a Nonlinear Energy Sink

The nonlinear energy sink (NES) and Galfenol material can achieve vibration suppression and energy harvesting of the structure, respectively. Compared with a linear structure, the geometric nonlinearity can affect the output performances of the cantilever beam structure. This investigation aims to present a coupled system consisting of a nonlinear energy sink (NES) and a cantilever Galfenol energy harvesting beam with geometric nonlinearity. Based on Hamilton’s principle, linear constitutive equations of magnetostrictive material, and Faraday’s law of electromagnetic induction, the theoretical dynamic model of the coupled system is proposed. Utilizing the Galliakin decomposition method and Runge–Kutta method, the harvested power of the external load resistance, and tip vibration displacements of the Galfenol energy harvesting model are analyzed. The influences of the external excitation, external resistance, and NES parameters on the output characteristic of the proposed coupling system have been investigated. Results reveal that introducing NES can reduce the cantilever beam’s vibration while considering the geometric nonlinearity of the cantilever beam can induce a nonlinear softening phenomenon for the output behaviors. Compared to the linear system without NES, the coupling model proposed in this work can achieve dual efficacy goals over a wide range of excitation frequencies when selecting appropriate parameters. In general, large excitation amplitude and NES stiffness, small external resistance, and small or large NES damping values can achieve the effect of broadband energy harvesting.