Research On The Micro-power Generation System With With Amplified Vibration Frequency

The distributed wireless sensor network has brought rapid changes to people’s lives,which facilitates people’s travel,life and consumption.In the distributed wireless sensor network,the nodes is increasing explosively,and more and more sensors are on the nodes,so it is more and more important to provide reliable power for the sensors.The traditional chemical battery as the energy supply device of the sensor has many shortcomings,limited life,long-term power supply,which can not meet the requirements of long-term reliable power supply.Efficient and reliable energy supply is an urgent problem to meet the demand of sensor power supply and promote its development.In practical application,when the wireless sensor can transform the energy collection technology into the available power to realize self power supply,the large-scale deployment has commercial and environmental significance.We propose a micro power generation system in this paper,which uses mechanical structure to achieve frequency amplification and can collect energy in low-frequency vibration environment.Micro power generation system is composed of two systems:one is vibration pickup system,the other is energy conversion system.The physical model of the vibration pickup system is established.The free vibration process with damping,the forced vibration process with simple harmonic,the simple harmonic vibration caused by the vibration of the support structure and the nonlinear analysis of the vibration pickup system are analyzed in turn.The amplitude frequency response curve under the state of response vibration is made,and the influence of the excitation source and damping ratio on the response vibration displacement is analyzed.ANSYS software is used to model and simulate the plane spring.The elastic coefficient of the plane spring and the related factors of the natural frequency are compared,and the respective relationship curves are obtained.At the same time,ANSYS software is used to analyze the vibration modes of the cantilever under the first,second and third natural frequencies.Compared with the first,second and third modes of the cantilever simulated by MATLAB software,the results are basically consistent.Three kinds of permanent magnet structures are designed.In this paper,we used Ansoft to simulate and analyze the magnetic field of these three kinds of permanent magnet structures.Among them,the combination mode of permanent magnet perpendicular to the magnetization direction is the most suitable,which can focus the magnetic field on one side.The physical model of the energy conversion system is established.The energy conversion process is divided into linear vibration and nonlinear vibration.In the vibration environment,the excitation source is large,the plane spring has large deformation,and the nonlinear vibration occurs.The vibration process in the nonlinear situation is not adverse.The amplitude frequency response curve will be widened,that is to say,the working frequency range can be widened,so the system output power is larger under the condition of nonlinear vibration.The working principle of the micro power generation system which uses mechanical structure to realize frequency amplification does not resonance.When the vibration amplitude of the external environment is high enough,the cantilever beam can be released from the mechanical barrier arm to further amplify the frequency,transfer the vibration to the next level structure,and complete the transmission and conversion of the vibration energy.The research work of this paper enriches the theoretical basis and analysis method of the physical modeling of each module of the micro power generation system,and provides technical support for the further development of the micro power generation system.