Vibration Energy Harvesting System Research Articles

A vibration energy harvesting system for Self-Powered applications in heavy railways

Heavy-duty trains with intelligent autonomous rail transit systems play an essential role in transporting goods and storing a large amount of energy to make it more sustainable. This paper presents a vibration energy harvesting system using a two-ball pair mechanism to collect track vibration for power sensors of a heavy railway network. The track vibration input module, motion conversion module, generator module, and energy storage module are essential subdivisions of the proposed system. The reciprocating linear vibrations of the track are transferred to the motion conversion module via the track vibration input module. The motion conversion module converts the vertical vibration into unidirectional rotation by employing a two-ball pair mechanism. The generator module utilizes the unidirectional rotary motion to generate electricity and is stored in an energy storage module. The performance of the energy harvesting system is evaluated based on simulation and experimental analyses under similar boundary conditions and found a good agreement between the results. The results indicate a maximum performance of 48.3% with an output power of 0.928 W, and this power is sufficient for self-propelled applications around heavy railways.

Validation and Evaluation of a Behavioral Circuit Model of an Enhanced Electrostatic MEMS Converter

In this current study, the validation and evaluation of a behavioral circuit model of electrostatic MEMS converters are presented. The main objective of such a model is to accurately find the converter behavior through the proper choice of its circuit elements. In this regard, the model enables the implementation of the electrostatic MEMS converter using commercially available off-shelf circuit elements. Thus, the overall vibration energy harvesting system can be implemented and tested without the need for fabricating the converter. As a result, the converter performance can be verified and evaluated before its fabrication which saves the expenses of fabricating trailed prototypes. To test the model, we apply it to an enhanced converter in which the conventional electrostatic MEMS converter is modified by depositing the tantalum pentoxide, Ta2O5, a high dielectric constant material, on its fingers’ sidewalls. Such a deposition technique causes an appreciable increase in the overall converter capacitance and, in turn, the output power, which is boosted from the range of µw to the range of mW. Next, the converter behavioral circuit model, which is based on representing its capacitances variations with respect to the input displacement, x caused by the vibration signal, C–x curve, is built up. The model is qualitatively validated and quantitatively evaluated. The enhanced converter performance is investigated through the interaction of its model with the power conditioning circuit. From the simulation results, it is revealed that the converter behavioral circuit model accurately accomplishes the vibration energy conversion operation. As a result, the specification of the required controlling pulses for the converter operation is accurately determined. Finally, the model accuracy is validated by calibrating its performance with a traditionally simulated and fabricated electrostatic MEMS converter.

A novel vibration energy harvesting system integrated with an inertial pendulum for zero-energy sensor applications in freight trains

With the development of the global economy, the demand for freight trains continues to rise, and the safety and maintenance of freight trains are essential. Therefore, sensors used for onboard monitoring of freight trains are vital components. However, the lack of onboard energy sources on freight trains makes the self-powering of sensors an urgent problem. In this paper, a novel renewable vibration energy harvesting system (VEHS) has been designed to provide electricity to sensors in freight train monitoring systems. The proposed VEHS mainly consists of three components: an energy input module, a motion transformation module, and an energy conversion module. The energy input module is composed of an inertial pendulum and a mass block. The movement transformation module integrates a novel and compact mechanical rectifier mechanism. The energy conversion module includes generators and energy storage devices. The wheel-rail coupled vibration is transformed into mechanical reciprocating rotation via the energy input module, and then into unidirectional mechanical rotation via the motion transformation module. Finally, the energy conversion module converts that mechanical energy of unidirectional rotation into electrical energy, and stores this micro-energy in a capacitor after rectification and boosting. Based on multi-body dynamics software and Simulink, a dynamic model was established to evaluate the vibration response of the system under different axle load and speed. Experiments revealed that the peak output power and energy harvesting efficiency of the VEHS were 1.04 W and 68.29 %, respectively. The RMS value of output power reaches 102.4 mW. In addition, this paper studies the application of the proposed VEHS to the China-Europe Express train. The results show that the system can be used to self-supply energy for freight train monitoring systems.

A Magnet-Coil-Type Bistable Vibration Energy Harvester for Random Wave Environment

In this study, a new bistable vibration energy harvesting system is developed by originally proposing a bistable vibration model comprising a spring and a mass block and then applying a vibration generator composed of a coil and a magnet. The nonlinear equations of motion for this vibration energy harvesting system are developed and the static potential energy distribution is analyzed. The bistable vibration characteristics and the method for prediction of the periodic excitation frequency at which stochastic resonance is likely to occur are investigated theoretically, and the electromagnetic induction-based bistable vibration energy harvesting system is then developed. We predicted the excitation value that the stochastic resonance phenomenon is most likely to occur at 1.543 Hz. We also conducted experiments at 1.15 Hz, 1.50 Hz, and 1.85 Hz, which are centered on the predicted value. As a result, stochastic resonance occurred in all experimental cases. The power generation efficiency was improved by 125.03%, 149.05%, and 95.39%, respectively.

Recent Advances in Hybrid Energy Harvesting Technologies Using Roadway Pavements: A Review of the Technical Possibility of Using Piezo-thermoelectrical Combinations

Currently, we are facing an energy transition due to pollution and depletion issues related to fossil energy sources. Among all the efforts to develop alternative green energy sources, there are other energy sources that remain unexplored. Ambient energies present on roadway pavements are one example. Thermal energy from solar radiation and the mechanical vibrations induced by passing vehicles are promising ambient energy sources available from roadway pavements. The aim of this study is to examine the existing energy harvesting systems for these ambient energy sources. This paper also summarizes existing study efforts on hybrid (thermal and mechanical vibration) energy harvesting systems in general. This hybrid system can overcome the limitations of a single source-based system as intermittent and low power generation. Energy harvesting technologies can generate green energy without negative environmental impact during the conversion process. This article solely contains references to studies examining the technological feasibility of a road energy harvesting project. Despite their importance, this bibliographic research did not include attempts to address costs, life cycle analyses, or the impact of the systems on the road structure. The reasons for this omission are due to the difficulty of obtaining this information in the scientific literature for comparison with the suggested systems.

Probabilistic Response and Performance Predict of Nonlinear Vibration Energy Harvesting Systems Based on Partial Information

Vibration energy harvesting technology is a hotspot research area in energy harvesting technology because it can convert the vibrational energy in the environment into electrical energy for output and thus provide the distributed energy for microelectromechanical systems. To improve the energy harvesting performance of the vibration energy harvesting system with partial information, we analyzed the probabilistic response of the stochastic system excited by Gaussian white noise under different geometric structures and effectively predicted the corresponding energy harvesting performance. Firstly, we established the coupling moment equation of the vibration energy harvesting system with the cumulant truncation method and then obtained some high-order moments. Then, the probability density function of the stationary response was set in exponential form with unknown parameters by using the maximum entropy principle, and those the unknown parameters will be obtained by solving the minimum value of an objective function, which contains the obtained moment information. Finally, the effects of the physical parameters (including geometric structure parameters and Gaussian white noise) on the dynamic behavior of the vibration energy harvesting system with only partial information have been studied and verified all results by direct numerical simulation.

Dynamic and Energetic Characteristics Comparison of a Tri-Stable Vibration Absorber and Energy Harvester Using Different Permanent Magnet Arrays

In this paper, it has been demonstrated that the tri-stable energy harvesters are more efficient than the bi-stable and mono-stable harvesters in energy harvesting. The oscillators of energy harvesters can be designed as a vibration absorber to attenuate the vibration of the primary system. This paper presents a combined vibration absorber and energy harvester (VAEH) system for simultaneous vibration control and energy harvesting, and the dynamic performances of the VAEH with two magnet arrays of the same geometric parameters, but opposite polarity external magnets, are studied. The mathematical model of the tri-stable VAEH is established, by which the dynamic and energetic characteristics of the VAEH system are obtained. It is found that the potential barrier and potential well depth of the repulsive magnet array are greater than the attractive one, reducing the voltage harvesting efficiency under harmonic and impulsive excitation. Both the amplitude and frequency of excitation are crucial to the dynamic response of the VAEH system. The attractive VAEH performs better than the repulsive VAEH in vibration suppression, especially for high impulse input. From the frequency response of the system, the vibration of the primary system is shown to be magnified at certain frequencies. The magnified primary system vibration and the harvested voltage can be attenuated by increasing the VAEH damping, which is a critical parameter to balance the weight of vibration suppression and energy harvesting. The attractive VAEH designed in this paper performs better than the repulsive one in vibration suppression and energy harvesting.

Performance analysis of nonlinear vibration energy harvesting system with inelastic barrier under colored noise excitation

The vibro-impact structures are introduced into the piezoelectric vibration energy harvesting (VEH) systems, which can broaden the operating bandwidth of the piezoelectric VEH systems and thus improve the harvesting efficiency. The process of vibro-impact not only causes energy loss during the impact process but also causes the local deformation between two impact bodies. Therefore, this manuscript proposes a class of stochastic non-classical inelastic impact VEH models, whose non-classical impact processes are described by Hertz contact forces. Firstly, the relationship between the total energy of the unperturbed system and the potential energy of the system at the barrier position is used to determine whether the impact phenomena have occurred or not, then used to derive the period and frequency of the system. Secondly, using the quasi-conservative stochastic averaging method, the averaged drift term and the averaged diffusion term of the piecewise smooth averaged Ito^ equation are derived. The stationary probability density functions (PDFs), the mean square output (MSO) voltage and the root mean square (RMS) voltage of the system response can be obtained from solving the corresponding Fokker-Planck-Kolmogorov (FPK) equation for averaged Ito^ equation. Finally, an example is provided to verify the effectiveness of the proposed method, and the effects of the model parameters on the MSO voltage and power conversion efficiency (PCE) are analyzed. The relationship between the MSO voltage and the PCE is also analyzed. It is of great significance for the design and optimization of stochastic VEH systems.

A rotational multi-stable vibration energy harvesting system

A rotational multi-stable vibration energy harvesting system

Investigations on energy harvesting systems incorporating mechanical and electrical nonlinearities to charge reusable batteries

This report analyzes the electromechanical coupling evident in vibration energy harvesting systems that charge reusable batteries. A model of a vibration energy harvesting system with far-from-equilibrium nonlinearities is considered for sake of capitalizing on high-energy forced vibrations. The piezoelectric structure is coupled with nonlinear interface circuits that leverage rectification and control stages to enhance power delivery to the battery. Three circuits, namely standard energy harvesting (SEH) circuit, parallel synchronized switching harvesting on inductor (P-SSHI) circuit, and synchronized charge extraction (SCE) are considered as interfaces between the nonlinear energy harvester and a battery. A simplified power calculation is numerically verified to accurately estimate the harvested power respectively delivered from three interface circuits to the battery. The investigations reveal that increasing required battery voltage may inhibit means to achieve high-energy vibrations and thus prevent battery charging. By a conservation of energy, it is shown that the phase lag between beam velocity and the base acceleration is the primary indicator of interference between dynamic energy flows in the electromechanical sub-systems. This research sheds light on the influences of energy storage components on the functioning of nonlinear vibration energy harvesting systems. Moreover, the principles uncovered for the inhibition of high-energy oscillation may guide future nonlinear energy harvesting system design to extract the best power out from the ambient vibration environments.

Response of a stochastic multiple attractors wind-induced vibration energy harvesting system with impacts

Focusing on multiple attractors wind-induced vibration energy harvesting system with unilateral impact under the excitation of Gaussian white noise, the stochastic response characteristics, and energy harvesting performance of the systems are presented and discussed. The stochastic averaging of the energy envelope and a conversion mechanism for decoupling the electromechanical equations are introduced to derive the theoretical probability density functions. Numerical simulation results are given to verify the correctness of such theoretical methods. Effects of the noise intensity, restitution coefficient, time constant ratio and coupling coefficient on the mean square voltage are analyzed. It is found that increments of the restitution coefficient and the piezoelectric coupling coefficient of the electrical part have a positive effect on the output voltage of the system, while other factors are opposite. Analysis can help explain the physical mechanisms of the system and provide ideas for optimizing energy harvesting performance by properly tuning the coefficients.

Piezoelectric Actuators Mode of Vibration Influence on Energy Harvesting Applications

At this research, the authors have been focused on the mechanical and vibrational energy harvesting system with piezoelectric actuators. By studying the characteristics vibration modes of the piezoelectric harvester and the clamping setup configuration, a design optimization has been carried out in order to analized its influence on energy scavenging.

Low-voltage broadband piezoelectric vibration energy harvesting enabled by a highly-coupled harvester and tunable PSSHI circuit

This paper presents a system-level design approach for widening the bandwidth and lowering the operating voltage of a piezoelectric vibration energy harvesting system (PVEHS). The proposed strategy involves co-optimization of the two constituent parts: (1) a highly-coupled piezoelectric vibration energy harvesting device (PVEHD) and (2) a phase-shift tunable parallel-SSHI (PS-PSSHI) interface power-electronic circuit. First, we analyze the interaction between them to achieve an overall reduction of system voltage and to widen bandwidth. Next, a co-designed system is experimentally demonstrated to validate the analysis. The implemented PVEHS consists of (i) a customized PVEHD designed for high electromechanical coupling and well-separated short-circuit (f SC) and open-circuit (f OC) resonances, and (ii) a tunable PS-PSSHI circuit which has an active rectification with low voltage drop to increase system efficiency. The system achieves an output power of 148 µW with a bandwidth of 81 Hz, an increase of 337% compared to conventional full-bridge rectifier. In addition, the system rectification voltage is lowered by 30% which makes it viable to power low-voltage Internet-of-Things sensor nodes.

Analysis of Double Elastic Steel Wind Driven Magneto-Electric Vibration Energy Harvesting System

This research proposes an energy harvesting system that collects the downward airflow from a helicopter or a multi-axis unmanned rotary-wing aircraft and uses this wind force to drive the magnet to rotate, generating repulsive force, which causes the double elastic steel system to slap each other and vibrate periodically in order to generate more electricity than the traditional energy harvesting system. The design concept of the vibration mechanism in this study is to allow the elastic steel carrying the magnet to slap another elastic steel carrying the piezoelectric patch to form a set of double elastic steel vibration energy harvesting (DES VEH) systems. The theoretical DES VEH mechanism of this research is composed of a pair of cantilever beams, with magnets attached to the free end of one beam, and PZT attached to the other beam. This study analyzes the single beam system first. The MOMS method is applied to analyze the frequency response of this nonlinear system theoretically, then combines the piezoelectric patch and the magneto-electric coupling device with this nonlinear elastic beam to analyze the benefits of the system’s converted electrical energy. In the theoretical study of the DES VEH system, the slapping force between the two elastic beams was considered as a concentrated load on each of the beams. Furthermore, both SES and DES VEH systems are studied and correlated. Finally, the experimental data and theoretical results are compared to verify the feasibility and correctness of the theory. It is proven that this DES VEH system can not only obtain the electric energy from the traditional SES VEH system but also obtain the extra electric energy of the steel vibration subjected to the slapping force, which generates optimal power to the greatest extent.

Design strategy for optimizing the bandwidth of the hardening vibration generator with customized response

For popular nonlinear vibration energy harvesting systems, such as the Duffing type or the piecewise type, the stiffness profile generally follows a specific explicit expression. The response is thus determined by the coefficients of the stiffness expression and the performance trade-off between high- and low- frequency ranges always exists. To break the restriction, the non-typical nonlinear system whose stiffness profile is arbitrarily variable without an explicit expression is a promising approach. This paper proposes a novel design strategy for the hardening system to optimize the bandwidth. A customized response composed of the starting segment and the flat transition segment is firstly sketched for a target frequency range. The first segment is adopted from a linear oscillator with the rapidly increasing response while the second segment is a straight line connecting the response peak at the high cut-off frequency to the starting segment at the low-end frequency. By finding out the flattest straight line for the transition segment, the high-frequency response is ensured and the low-frequency response is maximized at the same time. Experimental tests on an elaborated prototype show that the designed generator can achieve the optimized response as desired. The superior performance due to the performance enhancement in the low-frequency range is confirmed by comparison with literature generators.

Nonlinear vibration energy harvesting and vibration suppression technologies: Designs, analysis, and applications

Limited by the structure, the high-efficiency vibration energy harvesting and vibration suppression have always been a theoretical bottleneck and technical challenge in this field. The nonlinear design of the new vibration structure is an indispensable link in the development of vibration energy harvesting and vibration suppression technologies. Nonlinear technologies not only have the potential to improve the efficiency of the energy harvesters by increasing the useful frequency bandwidth and output power but also have the potential to improve the efficiency of vibration suppressors by reducing the transmission rate and transfer energy. Nonlinear vibration energy harvesting and vibration suppression technologies have been salient topics in the literature and have attracted widespread attention from researchers. The present work provides a comprehensive review on the recent advances in nonlinear vibration energy harvesting and vibration suppression technologies. In particular, the latest developments in multifunctional hybrid technologies are proposed. Various key aspects to improve the performance of nonlinear vibration energy harvesting and vibration suppression systems are discussed, including implementations and configuration designs, nonlinear dynamics mechanisms, various optimizations, multifunctional hybrid, application prospects, and future outlooks.

A machine learning approach for maximizing direct current power of nonlinear energy harvesting systems subjected to periodic impulse excitation

Vibration energy harvesting is a thoroughly tested approach to support the growing number of Internet-of-Things devices by providing a local and sustainable electrical power resource. Yet, the discovery of best practices for deploying vibration energy harvesters in environments is limited by inability to decipher high-dimensional data associated with design and implementation details. The study aims to devise one such approach to conclusively identify conditions under which an impulse-excited nonlinear energy harvesting system delivers peak electrical power. To accomplish this goal, physics-based and machine learning algorithms are integrated to uncover the underlying relationships between the impulse-induced nonlinear dynamics and the result converted electrical energy. The accuracy of the predictions from a machine learning model are confirmed through experiments and against cross-validation simulation data. The parameters that result in snap-through, as determined through machine learning methods, are then probed through a first-principles model to confirm that optimal circuit design conditions agree with the principle of impedance matching. The findings guide attention to previously unseen nuances of exploiting nonlinear vibration energy harvesting systems in impulse excitation environments by revealing parameter sensitivities that inhibit or promote the realization of snap-through vibration for peak power generation. This research demonstrates a successful synthesis of machine learning algorithms and first principles models to guide attention to optimal designs of nonlinear energy harvesting systems subjected to periodic impulse excitation.

Response Identification in a Vibration Energy-Harvesting System with Quasi-Zero Stiffness and Two Potential Wells

In this paper, the frequency broadband effect in vibration energy harvesting was studied numerically using a quasi-zero stiffness resonator with two potential wells and piezoelectric transducers. Corresponding solutions were investigated for system excitation harmonics at various frequencies. Solutions for the higher voltage output were collected in specific branches of the power output diagram. Both the resonant solution synchronized with excitation and the frequency responses of the subharmonic spectra were found. The selected cases were illustrated and classified using a phase portrait, a Poincaré section, and recurrence plot (RP) approaches. Select recurrence quantification analysis (RQA) measures were used to characterize the discussed solutions.

Resonance response analysis of nonlinear vibration energy harvesting system under bounded noise excitation

In this paper, the resonance response of piezoelectric vibration energy harvester (VEH) driven by bounded noise is discussed through the quasi-conservative stochastic averaging method. A nonlinear transformation based on the total energy is firstly established to transform piezoelectric VEH system from an electromechanical coupled nonlinear system into a single-degree-of-freedom (SDOF) system. Then the SDOF system is rewritten as It\^o stochastic system about the energy and residual phase under the case of p:q resonance through the quasi-conservative stochastic averaging method. And the joint probability density function (JPDF) of the stationary response is obtained by solving the corresponding two-dimensional Fokker-Planck-Kolmogorov (FPK) equation using the finite difference method. Meanwhile, the mean-square electric voltage and the mean output power are further analytically given through the JPDF. Finally, the resonance response of piezoelectric VEH system is analyzed in detail in case of the primary resonance, and the Monte Carlo (MC) simulation technique is adopted to validate the effectiveness of the finite difference method.

Transient response of a nonlinear energy sink based piezoelectric vibration energy harvester coupled to a synchronized charge extraction interface

Integration of a piezoelectric transducer with a nonlinear energy sink (NES) has been realized for both vibration mitigation and broadband energy harvesting. However, to ensure that a harvester can generate power in a truly broadband manner, the impedance matching issue of the interface circuit should be addressed. The synchronized charge extraction (SCE) is one technology that has been proved to be able to address this issue for linear energy harvesters. This work intends to investigate the transient response of an NES-based piezoelectric vibration energy harvesting system interfaced with an SCE interface (NESVEH-SCE). The nonlinear normal mode of such an electromechanically coupled system is analyzed on the basis of the equivalent impedance method and complexification-averaging method. The frequency-energy plots are depicted and verified by wavelet analysis. The effects of electromechanical coupling strength, electrical load in the SCE interface and initial input energy level on the performance of the proposed system are discussed by using the circuit simulation tool. Finally, experiments are performed to verify the consequences obtained from the theoretical and numerical methods, and demonstrate that the energy harvested during the transient response of the NESVEH-SCE system is independent of the electrical load in the SCE interface.