Mathematical Modeling And Partial Parameter Optimization Of Cantilever Magnetostrictive Vibration Harvesting System

In recent years,microelectronic devices are widely used in many fields such as industry,military affairs,aerospace,biomedicine,environmental detection and so on.At present,the main power supply mode of these devices is chemical battery.However,billions of batteries produced every year will have harmful effects on the environment,and even damage the components themselves.With the progress of science and technology and the rapid development of electronic market,the energy consumption of miniature electronic components has been reduced to m W andμW,which promotes the development of energy collection technology and self-powered components.The energy collection technology collects various forms of energy(solar energy,thermal energy,mechanical energy,etc.)from the surrounding environment to generate electric energy,and replaces the traditional battery or prolongs the service life of the traditional battery for supplying power to electronic equipment.Vibration energy collection converts the common mechanical vibration in the surrounding environment into electric energy,which can realize self-power sensing,control and drive,and has the advantages of convenience,energy saving,environmental protection and sustainability.However,it has some shortcomings,such as low output power,low efficiency,poor environmental adaptability and low reliability,which limit its practical application.Therefore,it is necessary to optimize the structure and parameters of the harvester to adapt to the characteristics of environmental vibration,and then improve the collection ability of mechanical energy.Due to the low vibration frequency and weak vibration energy in the natural environment.Therefore,the practical application conditions of vibration energy collection are particularly harsh.Therefore,it is necessary to optimize the structure and parameters of the harvester system,adjust the working frequency and adapt to the characteristics of environmental vibration,so as to improve the harvester ability of mechanical energy.In this paper,a clear mathematical model for the cantilever magnetostrictive vibration harvester based on the base excitation is established from the perspective of the energy conversion relationship among mechanical energy,magnetic energy and electric energy.The research results are analyzed and verified from two aspects of numerical calculation and experiment.The additional weight,coil parameters,external resistance and other parameters of the harvester are optimized and analyzed.It was experimentally verified that the optimized magnetostrictive harvester can output 12.07 mW power to the external resistor under the condition of 1g acceleration mechanical vibration and the normalized power density reached to 40.2 mW/cm~3/g,compare with the non-optimized vibration energy collection device,the power density is increased by 14.2 times.The optimized magnetostrictive harvester successfully powered for LED display screen of the temperature sensor and a low-power thermometer.