Structure Of Piezoelectric Energy Harvester Research Articles

Hand-held piezoelectric energy harvesting structure: Design, dynamic analysis, and experimental validation

This research proposes a hand-held piezoelectric energy-harvesting structure for portable human-motion energy harvesting. The proposed structure is composed of a square support frame with two hand shanks, a rotation disk with four identical rectangular permanent magnets, and a 33-Mode piezoelectric patch with a rectangular permanent magnet attached. Piezoelectric materials with good d33 piezoelectric properties and high rigidity can be applied to the proposed structure. The dynamic changes of the proposed structure in the electric and magnetic fields during rotation are simulated and analyzed in detail. Treadmill experiments were also conducted to validate the simulation results. The results showed that the maximum peak-to-peak alternating piezoelectric voltage yields 3.5 V at 8 km/h and 0 degrees. Within 6.7 min, the 100 μF capacitor can be charged to 1.2 V, and the corresponding average power is equal to 0.18 μW at 6 km/h and 0 degrees.

Study on Wind Energy Harvesting Effect of a Vehicle-Mounted Piezo-Electromagnetic Hybrid Energy Harvester

To realize the self-power of the vehicle micro-sensors, a piezo-electromagnetic hybrid vehicle-mounted energy harvester is proposed to recover the wind and vibration energy generated during driving. This energy harvester includes a flutter piezoelectric energy harvesting structure (FPEH) and an electromagnetic vibration energy harvester structure (EVEH). The combination of the two structures can improve the energy harvesting effect and reduce the cut-in wind speed. The coupled vibration mathematical model is established to predict the output performance of the wind energy harvesting effect. The effects of the different distances between magnets on the output are discussed. And the vibration characteristics of piezoelectric and electromagnetic vibrators are analyzed. Results show that the energy-harvesting effect is the best when the distance between magnets is 30mm. At the same time, the numerical simulation proves that the wind energy harvesting effect of the hybrid structure is better than the classic flutter structure. The experimental verification is carried out, and the experimental results are consistent with the theoretical prediction results, which verified the correctness of the theory. The optimal load of FPEH is 70kΩ , and the optimal load of EVEH is 60Ω. Under these conditions, when the wind speed is 18m/s, the peak output power of FPEH is 14.5mW, and that of EVEH is 31.8mW.

Study of a Piezoelectric Energy Harvesting Floor Structure with Force Amplification Mechanism

This paper proposes a novel energy harvesting floor structure using piezoelectric elements for converting energy from human steps into electricity. The piezoelectric energy harvesting structure was constructed by a force amplification mechanism and a double-layer squeezing structure in which piezoelectric beams were deployed. The generated electrical voltage and output power were investigated in practical conditions under different strokes and step frequencies. The maximum peak-to-peak voltage was found to be 51.2 V at a stroke of 5 mm and a step frequency of 1.81 Hz. In addition, the corresponding output power for a single piezoelectric beam was tested to be 134.2 μW, demonstrating the potential of harvesting energy from the pedestrians for powering low-power electronic devices.

Design and optimization of a broadband piezoelectric energy harvester

The conventional linear cantilever piezoelectric energy harvester has a relatively narrow working frequency range (1-2 Hz) and low energy harvesting performance. Therefore, a new effective host structure needs to be developed. This paper proposes a broadband piezoelectric energy harvesting structure to solve this problem. The proposed structure is composed of three beams. Based on the finite element analysis via ANSYS software, the theoretical model of this structure is established. The response characteristics of the energy harvester are analyzed, and the optimization design strategy is presented. The finite element simulation results show that the working frequency range of the presented harvester can be changed by adjusting the length ratio of each beam. Therefore, the result indicated that the proposed energy harvesting structure can widen the effective bandwidth and improve the energy harvesting performance.

Study on the Energy Harvesting Performance of PE Cantilever Beam

Harvesting ambient vibration energy through piezoelectric (PE) means is a popular energy harvesting technique. The merit of applying PE means to supply energy for microelectronic devices is that they can reduce the battery weight and possibly make the device self-powered by harvesting mechanical energy. This investigation will examine the energy generating performance of miniature PE cantilever beam through theoretical modeling, simulation and experiment testing. Through the theoretical analysis of the piezoelectric energy harvesting structure, the expression of open circuit voltage output is obtained. Using ANSYS software, the working performance of piezoelectric cantilever beam is analyzed. On the basis of theoretical analysis and simulation optimization, a set of experimental system is established to test the energy harvesting performance of the piezoelectric cantilever beam. The testing result shows that the harvested energy by the piezoelectric cantilever beam could supply electrical power to some micro electrical devices.

An Improved Tunable Piezoelectric Energy Harvesting Structure Based on d33 Mode Coupling

This research proposes an improved tunable piezoelectric harvester structure which is constructed by a cantilever base beam and piezoelectric elements working in d33 mode. Our previous work on tunable piezoelectric harvester structure showed a frequency variation ratio of 3.17% with piezoelectric elements working in d31mode coupling. In this work, by changing the working mode of the piezoelectric elements from d31 to d33 mode, the frequency variation ratio was shown to be much higher. Theoretical analysis of the improved structure was investigated and verified with simulations. The results showed that the d33 mode coupling surpasses the d31 mode coupling with a frequency variation ratio of 29.74%.

A low frequency and broadband piezoelectric energy harvester using asymmetrically serials connected double clamped–clamped beams

A novel structure of piezoelectric energy harvester was developed using double clamped–clamped beams serials connected by a rectangular frame, coupled with a proof mass and supporting mass near the center of upper and lower beams. The serials connection has a significant effect on reducing the resonance frequency, which is predicted by theoretical analysis and validated by experimental, and a reduction of 36.7% is achieved compared with the single clamped–clamped beam. More importantly, the bandwidth of the power spectrum is 36.4% wider, by introducing an asymmetry of 1 mm between the proof and supporting mass, than that of the symmetric setup. More than 0.8 mW ranging from 144 to 170 Hz is obtained near the two peaks of 0.992 mW at 150 Hz and 0.844 mW at 165 Hz, respectively. For its lower frequency, broader bandwidth and compact volume, the asymmetric harvester has promising application in wireless sensors networks.

Design optimization and experimental analysis of Piezoelectric Energy harvester

This paper describes an approach to harvest electrical energy from a mechanically excited piezoelectric element. The structure of piezoelectric energy harvester is optimized for maximum power with minimum dimensions through Genetic Algorithm approach to enhance the conversion of mechanical energy into electrical energy using direct piezoelectric effect. Numerical analysis is carried out to obtain optimal PZT position on the cantilever beam to get maximum harvested power. A rectifier with boost converter IC is used for converting harvested power in to usable DC power. The simulation results are verified experimentally.

Reduced-Order Aerodynamic Modeling of Flapping Wing Energy Harvesting at Low Reynolds Number

Energy harvesting from flowing fluids using flapping wings and fluttering aeroelastic structures has recently gained significant research attention as a possible alternative to traditional rotary turbines, especially at and below the centimeter scale. One promising approach uses an aeroelastic flutter instability to drive limit cycle oscillations of a flexible piezoelectric energy harvesting structure. Such a system is well suited to miniaturization and could be used to create self-powered wireless sensors wherever ambient flows are available. In this paper, we examine modeling of the aerodynamic forces, power extraction, and efficiency of such a flapping wing energy harvester at a low Reynolds number on the order of 1000. Two modeling approaches are considered: a quasi-steady method generalized from existing models of insect flight and a modified model that includes terms to account for the effects of dynamic stall. These two modeling approaches are applied to predicting the instantaneous aerodynamic force histories of an oscillating airfoil as well as parametric studies of the energy extraction efficiency. The modified model is shown to provide better agreement with computational fluid dynamics simulations of a flapping energy harvester.