风车型低频压电振动能量采集器的研究与设计

Research and Design of Low-frequency Piezoelectric Vibration Energy Harvester With Windmill Structure

基于微机电系统(MEMS)设计了风车型结构的压电振动能量采集器,通过压电效应将低频振动能量转化为电能,用以解决环境中低频能量采集的问题。风车型结构的压电振动能量采集器以硅为基底,以PZT-5A为压电材料,包含上、下电极;4条悬臂梁旋转连接中心质量块与四周固定端,类似于风车结构。数学建模与有限元仿真分析表明,在结构尺寸与材料相同的情况下,圆弧风车型结构的谐振频率较直接连接、直角连接结构的谐振频率更低;4条悬臂梁距离中心质量块越远,谐振频率越低;在0.1g(g=9.8m/s^2)加速度谐振状态下,输出电压约为6.2V,最大位移接近1.2mm。基于MEMS工艺,通过IntelliSuite软件研究和定义了风车型振动能量采集器的工艺流程。

A piezoelectric vibration energy harvester with windmill structure is designed based on MEMS. The low frequency vibration energy is converted into electric energy by piezoelectric effect, so as to solve the problem of low frequency energy acquisition in the environment. The piezoelectric vibration energy harvester uses silicon as the substrate, with PZT-5A as piezoelectric material, including upper and lower electrodes; four cantilever beams are rotated to connect the center mass blocks with fixed ends around, which is similar to the windmill structure. The results of mathematical modeling and finite element analysis indicate that under the same sizes and materials of the structure, the arc windmill type structure has lower resonant frequency than the direct connection and the right angle connection structure. The farther the 4 cantilever beams are from the center mass, the lower the resonant frequency. At 0.1 g（g =9.8 m/s^2） acceleration resonant, the output voltage is about 6.2 V, and the maximum displacement is close to 1.2 mm. On the basis of MEMS process, the process flow of windmill vibration energy harvester is studied and defined by IntelliSuite software.