The Power Generation And Dynamics Research Of The Vibration Energy Harvester With Magnet And Spring

With the development of micro-electro-mechanical technology and wireless communication technology,the application scope of micro-electronic equipment is expanding.It is not a long-term solution to rely on battery power supply for the fake and inferior working environment of many devices.How to find a new power supply mode for these micro-devices is a difficult problem.The piezoelectric energy collector based on piezoelectric effect can collect the vibration energy widely existing in the environment and convert it into electric energy,so one way to solve the problem of power supply is to add vibration energy collector to each equipment.One of the basic components of vibration energy collector is piezoelectric cantilever beam.There are many kinds of power generation modes of piezoelectric cantilever beam.Based on piezoelectric cantilever beam,this paper designs and studies the power generation characteristics and dynamic behavior of a kind of energy collector with additional magnet spring.Based on the traditional bistable piezoelectric cantilever beam and additional spring energy collector,a new type of energy collector with additional magnet spring is studied in this paper.In this paper,four kinds of piezoelectric energy collectors with magnet springs are designed,and 11 kinds of power generation modes of four kinds of structures are compared experimentally,and the optimal power generation structure is obtained.The parameters of the optimal structure are optimized,and the influence of each parameter on the power generation characteristics of the structure is analyzed.The comparison experiment between the optimal structure and the traditional bistable piezoelectric cantilever beam is carried out,and the similarities and differences of the power generation law and dynamic behavior between the optimal structure and the traditional bistable structure are analyzed.The dynamic equation of the structure with opposite magnet spring is deduced,the numerical analysis is carried out,and the power generation characteristics and dynamic behavior of the optimal structure are analyzed.The research contents are mainly divided into the following parts:(1)Comparing the four kinds of additional magnet spring energy collectors designed in detail,the basic principle is the control variable method.Under the same amplitude of external excitation,the optimal generation structure can be found by changing the frequency of external excitation.(2)By optimizing the parameters of the structure,the optimal structure is further studied.The influence of magnetic distance,end mass,cantilever beam length,upper and lower potential wells on the generation law of the optimal structure is studied.The optimal structure is compared with the traditional bistable energy collector,and the generation efficiency of the two structures under multiple magnetic spacing is compared,and the law of dynamic behavior is analyzed.(3)Based on Euler-Bernoulli beam theory,the piezoelectric cantilever structure is studied,and the dynamic equation of the energy collector with additional magnet spring is established by applying Hamilton principle.The numerical simulation is carried out by using MATLAB.The power generation characteristics and dynamic behavior of the system are studied by using voltage and displacement waveforms,phase diagrams and Poincare cross sections.Finally,in the appendix,two kinds of energy collectors based on piezoelectric effect are designed to be applied in engineering practice.One is a piezoelectric self-powered wireless mouse,and the other is a heating seat of a power supply vehicle based on piezoelectric material.The designed mouse and seat can collect the vibration energy of the working environment,convert it into electric energy,and supply power for their own structure.