Study On Design And Characteristics Of Magnetostrictive Vibration Power Generation System Using Lamellar Fe-Ga Alloys

With the development of low-power large scale integrated circuit designing and CMOS manufacturing,the power consumption of wireless sensor nodes is reduced from mW level to ?W level.The traditional battery-powered mode can not meet the needs of wireless power supply and long-term power supply,Energy issues have become one of the bottlenecks that affect and constrain the popularity and development of low-power electronic devices such as wireless sensors.The vibration energy in the environment is widespread.How to use it have became the research focus of scholars around the world,as a new type of functional material,the giant magnetostrictive material has the bi-directional conversion effect of mechanical energy and electromagnetic energy.By using the characteristics of the magnetostrictive inverse effect and Faraday’s electromagnetic induction the mechanical energy to electrical energy conversion process can be achieved.This paper use the inverse effect of giant magnetostrictive material as the theoretical basis.Based on the research development of giant magnetostrictive materials and the comparative analysis of the advantages and disadvantages of various giant magnetostrictive materials,the core material of the giant magnetostrictive vibration power generation device is established by using Fe-Ga alloy flakes.COMSOL Multiphysics multi-physics coupling method was used to establish the optimal fixing method of thin slices and the advantages and disadvantages of different excitation modes were analyzed.The bias magnetic field and induction current pick-up coil of power generation device were designed.Finally,the structural design of a magnetostrictive vibration power generation system with lamellar Fe-Ga as a core element was completed.Then the giant vibration power device sample was manufactured.Basing on the Jiles-Atherton magnetization model,the mathematic model of forced excitation,inertial excitation and vibrating power generation installed inside the tire is established.The power generation model is simulated by MATLAB.On this basis,a comprehensive experimental platform is set up to verify the power generation performance of the vibration power generation device under the conditions of forced excitation and inertial excitation.The experimental results are in good agreement with the simulation results.The mathematical model of the electro-mechanical coupling can be used to predict the performance of vibration power generation devic.Under the condition of forced excitation,the influence of acceleration,vibration frequency and bias magnetic field on power generation performance was explored.The peak voltage could reach 201 mv at 180 Hz excitation frequency and 6.25 mT bias magnetic field.Under the condition of inertial excitation,the vibration frequency,the influence of counter-weight on the generated voltage was explored,and the input and output power of the system were measured,the electromechanical conversion efficiency of the system and the effect of load impedance on output rate were also analyzed.The results show that the counter-weight can reduce the resonant frequency of the system,and also have an impact on the peak voltage.But the electromechanical conversion efficiency of the system is low which still needs to optimize the vibration power generation device in the futhre.The increase of load impedance will reduce the output power of the system.It can be seen that the system is suitable for low load impedance circuits.The results of the study have a promotional significance for the giant magnetostrictive vibration power generation device further research and application.