Design And Research On Energy Harvesting Device Based On Wafer Galfenol

In recent years,with the development of science and technology,the energy problems have been paid more and more attention by experts and scholars from all walks of life.In addition to reducing resource waste radically and increasing the efficiency of resource utilization,discovering and using the new energy instead of the traditional non-renewable resources has become the focus of scholars' research both at home and abroad.Mechanical vibration is the most popular form of energy in nature,it will not be affected by climate,time and place and then gave birth to a variety of energy harvest technology.There are some kinds of traditional energy harvest technology such as electrostatic,electromagnetic and piezoelectric method.The most deeply research of the above three ways is piezoelectric energy harvesting technology.With the deepening of the research of magnetostrictive materials,the experts and scholars have paid more and more attention on the magnetostrictive energy harvest technology.In this paper,a set of vibration energy harvester has been designed based on the laminar magnetostrictive materials and some researches are conducted.First of all,the development process of magnetostrictive materials and its working principle are introduced,the basic principle of magnetostrictive material relative to other intelligent materials in the field of energy collection is compared and analyzed.In numerous magnetostrictive materials,the performance of Galfenol and Terfenol – D have been compared.Because the former has a good mechanical performance,which can adapt to different device structures and does not contain rare earth elements and is in low price.Use Galfenol as the intelligent materials researched in this paper.Secondly,the constitutive relation of Galfenol will be obtained according to the electromechanical conversion principle.And the magnetization model will also be established after introducing the hysteresis model of Galfenol.And then according to the model,the classic electromechanical coupling model,the electromagnetic induction law and the electromagnetic principle,Galfenol's mathematical model of vibration energy harvesting is obtained.Additionally,based on the advantage of cantilever beam structure in the field of energy harvest technology(mainly characterized by simple structure and easy to miniaturization),the main structure of the vibration energy harvester designed in this paper is the cantilever beam structure.Some performance comparisons of the four types of cantilever beam shape(rectangular,trapezoidal,triangular and double curved shape)through relevant theoretical calculation after the bending vibration analysis and forced vibration analysis of the cantilever beam are conducted.Then,according to the result of statics analysis,modal analysis and harmonious response analysis of the cantilever beam,the size and the inherent frequency of the beam and the output voltage response of the device under the action of different vibration frequency is determined by using Ansys software.In addition,this paper has also designed other components of the device.Then,through the Matlab software in combination with the stress and strain theory calculation process of different shapes of the beams,the simulation output result of the mathematical vibration energy harvesting model is obtained.When the amplitude value of excitation is 20 um and the vibration frequency is their first order natural frequency respectively,the simulation output result of the peak-to-peak induction voltage values of the mathematical model are 145.7mV,177.8.4mV,225.3mV,279.7mV.Finally,the experiment of four kinds prototype output performance contrast have been conducted after the experimental prototype was designed,then the single factor and orthogonal experiment of the hyperbolic type experimental prototype have also been conducted.The experimental results show that the highest output peak-to-peak induction voltage value of four types experimental prototype is the hyperbolic type energy harvester,the average value is 269.8mV.In the single factor experiment,we have obtained the relationship between the peak to peak value of the output voltage and factors including excitation frequency,excitation amplitude and the bias magnetic field.In the process of orthogonal experiment result analysis,it is concluded that the excitation amplitude among the three factors in the influence of the experimental prototype output performance is most significant.