| Popis: |
As the power consumption of modern electronics and wireless circuits decreases to a few hundred microwatts, it becomes possible to power these electronic devices by using ambient energy harvested from the environment. Mechanical vibration is among the more pervasive ambient available energy forms. Recent works in vibration-to-electrical energy harvesters have been centered on high frequency vibration applications. Although high-frequency mechanical vibrations are more energy rich, for some situations the local ambient environmental vibrations tend to occur at lower-frequencies. For example, the highway vibration frequencies are mainly between 10 ~ 20 Hz. This paper discusses the development of a miniature vibration-to-electrical energy harvester based on electromagnetic methods using MEMS technology, targeted on the low vibration frequency regime in the 15 ~ 20 Hz range for potential use in highway structural health monitoring (HSHM) purposes or in other applications. Innovative design considerations need to be addressed to achieve this goal in a miniature package. For example, a highly pliant material and a heavy seismic mass are needed. In our design, SU-8 is chosen as a part of the composite material for the cantilever beam, micro-coil, and seismic mass fabrication. The mechanical characteristics of the energy harvester are simulated. The power generation capability of the designed energy harvester is calculated. |
