A Rolling-Based Broadband Low-Frequency Electromagnetic Vibration Energy Harvester

Traditional battery have many disadvantages,such as short service life?low power density?high pollution,so that it is difficult to supply energy for wireless sensor networks and implantable MEMS.As an ideal alternative energy sources, electromagnetic vibration energy harvester attracted more and more attention of domestic and foreign researchers. Due to environmental vibration most has the characteristics of broadband, low frequency,so it is of great significance to research high efficiency vibration energy harvesters to harvest environmental broadband low-frequency vibration energy.Based on the need of developing broadband ? low-frequency electromagnetic vibration energy harvester,the simulation model of the electromagnetic vibration energy harvester was built,the structure of the electromagnetic vibration energy harvester was designed and optimized,and the output performance of harvester was tested. Finally, the harvester was used to power for wireless sensor nodes. The main work is as follows:(1) The documents about electromagnetic vibration energy harvester from domestic to foreign were read. The situation and development trends in this area from domestic to foreign were summarized and analyzed;(2) Based on the energy conversion mechanism of electromagnetic vibration energy harvester and physical modal of energy collection and conversion systems of electromagnetic vibration energy harvester and existing models, the impact factor of output performance of harvester was analyzed. A new structure of broadband low frequency vibration energy harvester was proposed.(3) Based on theoretical models, combined with ANSYS finite element simulation, the simulation model of electromagnetic vibration energy harvester was built, and the simulation results was verified. The structural parameters of the electromagnetic vibration energy harvester was determined. The design of harvester structure was completed.(4) The final prototype of rolling-based broadband low-frequency electromagnetic vibration energy harvester was processed, and the output performance of harvester was tested. Under acceleration 1.5g, 26 Hz frequency vibration excitation, the maximum output of open-circuit voltage rms was 3.4V, the maximum output power was 0.91 mW.The half-peak working frequency was13.2~26 Hz, the half-peak working bandwidth was 53.1% or 12.8 Hz. When the external vibration excitation acceleration of 2g,frequency of 30 Hz, the wireless sensor node was driven by harvester successfully.