基于电磁感应和压电效应复合的变压器振动能量收集研究

Research on Hybrid Vibration Energy Collection Based on Electromagnetic Induction and Piezoelectric Effect for Transformer

如何给海量传感器供能是电力物联网建设亟待解决的问题,能量收集技术为解决该问题提供了一种可行方案。变压器在工频磁场的作用下广泛存在主频为100 Hz的振动能量,但一直缺乏有效的收集方式。文中采用悬臂梁谐振结构,设计制作了电磁感应与压电效应复合的振动能量收集器;测试了所制作能量收集器的频率响应特性,器件谐振频率为100Hz,压电部分与电磁部分的3dB频带宽度分别为4.1Hz与2.0Hz;在100Hz/5m·s^(-2)的振动条件下,压电部分与电磁部分的开路电压分别为44.98、6.85V,最大输出功率28.17mW,且可以在300 s内将100 mF电容充电至3.81 V。在实验室模拟条件及变压器现场测试条件下,测试了能量收集器的应用前景,所制作能量收集器通过收集变压器工作时外壳的振动能量,可以带动温湿度传感器件工作。

How to supply energy to massive sensors is an urgent problem to be solved in the construction of power In-ternet of things.Energy harvest technology provides a feasible solution to this problem.Transformer generates signifi-cant vibration energy with a main frequency at 100 Hz under action of the power frequency magnetic field.However,an effective harvest mode has been lacking.In this paper,a vibration energy harvester with electromagnetic induction and piezoelectric effect is designed and made by using the resonant structure of cantilever beam.The frequency re-sponse characteristics of the energy collector are tested.The resonant frequency of the element is 100 Hz,and the 3 dB bandwidths of the piezoelectric part and the electromagnetic part are 4.1 Hz and 2.0 Hz,respectively.Under the vibration condition of 100 Hz/5 m·s^(-2),the open-circuit voltages of the piezoelectric part and the electromagnetic part are 44.98 V and 6.85 V respectively.Under the same conditions,the maximum output power is 28.17 mW and har-vester can charge a 100 mF capacitor to 3.81 V in 300 s.Under the conditions of laboratory simulation and transform-er field test,the application prospect of the energy harvester is tested.The energy harvester can harvest the vibration energy of the transformer shell,charge the capacitor and drive the sensor.