Application Research And Design Of Environmental Enerey Harvester Based On MEMS Technology

With the development of science and technology and the need of practical application,the demand of data acquisition and network transmission node is increasing.These wireless sensor nodes have the characteristics of small size,wide distribution,low energy consumption,poor working environment and so on.Traditional chemical batteries are difficult to meet their energy supply requirements.To solve this problem,collecting and converting renewable energy in nature is an ideal way.The mechanical vibration energy can be transformed through a certain structure and continuously provides electrical energy for wireless sensor nodes.Firstly,the equivalent model of traditional single cantilever beam and mass block is analyzed and its motion equation is obtained based on the understanding of piezoelectric characteristics and performance parameters of piezoelectric materials.Then,the low-frequency piezoelectric vibration energy acquisition basesd on windmill structure was designed.The first three vibration modes,resonant frequency and harmonic response curves of cantilever beam structure are obtained by using MEMS simulation software.When changing the size of the cantilever beam,the simulation analysis shows that the longer,narrower and thinner the cantilever beam is,and the greater the distance from the center mass block is,the lower the resonance frequency will be.In addition,through the analysis and comparison of arc,straight and right Angle connection structure,it can be seen that the resonance frequency of arc connection cantilever beam is the lowest and the internal stress performance is the best.On the other hand,the circuit characteristics of the piezoelectric vibration energy acquisition structure are simulated,the output voltage and power are analyzed,the piezoelectric vibration energy acquisition circuit is designed,and the practical design of the piezoelectric vibration energy collector of the windmill structure is explored based on the two chips.Finally,based on photoresist,stripping,etching,oxidation and other basic MEMS technology,7 photoresist mask plates were designed for the piezoelectric vibration energy collector based on windmill structure,and the MEMS processing process was developed.The rationality and manufacturability of the piezoelectric vibration energy collector structure are verified through the analysis of structures,circuits and processes with IntelliSuite software.