| There is abundant vibration energy in the engineering environment which has not been used. Vibration-to-electrical technology can solve the power problems of low-power electronic equipment, such as the distributed sensors and portable electronic devices, and can be used to improve the energy utilization efficiency. This paper will theoretically and experimentally study the vibration-to-electrical technology on the basis of the giant magnetostrictive materials and permanent magnet materials.1.The mathematical model of giant magnetostrictive vibration-to-electrical generator (GMVEG) is proposed on the basis of piezomagnetic equations, Jiles-Atherton model, magnetomechanical coupling model of giant magnetostrictive material, law of electromagnetic induction and vibration equation. This model can describe the relationship among magnetostrictive coefficient, magnetization, vibration stress or displacement excitation, output electromagnetic force (EMF) of GMVEG. Based on this model, the simulation analysis is carried out on the condition of sinusoidal vibration excitation. The calculated results show that the output EMF of GMVEG is mainly depends on the vibration stress and frequency.2.The design and fabrication of GMVEG are studied in this paper, and the corresponding experimental platform is build. The impact of vibration source is experimentally studied on GMVEG. The peak-to-peak value of output EMF is 91.1 mV under the condition of excitation stress 0.05 MPa, frequency 47 Hz, the initial angle 5°, and induction coil turns number 100. The calculated value (107 mV) is in good agreement with the experimental one. When the vibration source is hand-held hammers, the peak-to-peak value of output EMF can be greater than 2 V and the power can be greater than 10 mW. Experimental results show that the output power will improve effectively on the condition of increasing vibration stress and frequency.3.The electromagnetic mechanical coupling mathematical model is deduced on the basis of vibrations and the law of electromagnetic induction. Unlike the relevant literatures only consider the induced EMF, the EMF of the proposed model contains the motional EMF and induced EMF. The vibration-to-electrical generation is simulated on the basis of the mathematical model. Simulated results show the output EMF of permanent magnet vibration-to-electrical generator (PMVEG) is proportional to the vibration frequency and displacement. And the motional EMF is significantly greater than induced EMF. The model can provide a theoretical guidance for the design of PMVEG.4.The definition and mathematical model are proposed on the equivalent turn number of coil. The model can provide a theoretical foundation for the coil design and describe the relationship among induction coil, magnetic field distribution, vibration, and output EMF. The research results indicate that the coil structure is mainly affected by the vibration waveform and magnetic field distribution, and the induction coil should be optimized. A linear load circuit and a nonlinear load circuit are established and simulated and it will provide foundation for the PMVEG design with higher energy conversion efficiency.5.PMVEG is fabricated and test rig is built for experimental study. The output EMF peak-to-peak value of direct vibration type generator is 2.32 V on the condition of vibration generator excitation, which agrees well with theoretical calculation. The voltage is 2 V after rectifier and filter. The peak-to-peak value of output EMF of permanent magnet spring type generator is 7.20 V on the condition of hand shake. The experimental results show that the PMVEG can reach the requirement of design and can provide the power for low-power electronic equipment. The research results will establish the basic guidance for the application of PMVEG.
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