基于微机电系统(MEMS)设计了一种结构新颖的横向电磁式振动能量采集器,用于把周围环境中振动的机械能转化为电能.该能量采集器主要由两块长方形永磁体、螺旋铜线圈、质量块-弹性梁振动系统及衬底等构成.选用有限元分析软件对器件结构参数进行了仿真分析与优化,并利用电镀技术制作螺旋铜线圈,KOH湿法腐蚀和深反应离子刻蚀(DRIE)技术制作质量块-弹性梁振动系统,然后与永磁体一起组成了体积大约为100 mm3的能量采集器样机.对制作好的电磁式振动能量采集器样机的振动特性测试表明:质量块-弹性梁振动系统的一阶固有频率为241 Hz;在频率为241 Hz、加速度为2.8 ms-2的外界振动激励下,负载两端产生的交流电压峰峰值为9.2 mV.另外调节质量块和弹性梁的参数,还可以得到不同固有频率的能量采集器.该能量采集器实现了从机械能到电能的转化,对无线传感器件的发展和应用很有意义.%A transverse electromagnetic vibration energy harvester based on Micro-electro-mechanical System(MEMS) was designed to convert the vibration mechanical energy around our environments to electrical powers. It mainly consisted of two vertically polarized rectangle permanent magnets, a mass-spring vibration system with a copper coil and a substrate. The structure parameters of system were analyzed and optimized by Finite Element Analysis (FEA) , and a harvester prototype was fabricated. During the fabrication of the harvester, electroplating technology was employed to fabricate a spiral copper coil, KOH wet etching and Deep Reaction Ion Etching(DRIE) technology were employed to fabricate mass-spring vibration system, then the harvester prototype was formed together with permanent magnets. The volume of the harvester was about 100 mm3. The test results for vibration characteristics show that the natural frequency of the mass-spring vibration system is 241 Hz. The electro-rnmagnetic vibration energy harvester can generate a peak-peak voltage of 9. 2 mV at an external acceleration of 2. 8 ms-2 and frequency of 241 Hz. Furthermore, by adjusting the parameters of mass-spring vibration system, the harvester with different natural frequencies can obtained. The havester can convert the mechanical energy to the electrical energy and have significance for the development and application of the wireless sensor devices.
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