EE Dept  |  ACAE Dept  |  Faculty of Engineering  |  CUHK

Eco-safe Human-motion-powered MEMS Energy Generator for Mobile Electronic Devices This project is funded by the Hong Kong Innovation and Technology Fund (ITS/185/01).

Investigators Introduction Historical Background  Principle & Design Resonation Structure Application Demonstration Infrared Transmission RF Signal Transmission Download Area CMNS Home

Principle and Design The prototype micro power generator consists of five main components: 1) inner and outer housing which is used to carry the resonating structure and the power generating system, respectively, 2) a laser-micromachined resonating spring, 3) a N45 grading rare earth permanent magnet, 4) copper coil, and 5) a power-management circuit for output voltage step up and energy storing purpose. The resonating spring is attached to the magnet and packed by the inner housing. The orientation of inner housing, magnet and the resonating spring and an illustrative drawing of AA size’s micro power generator are shown below.  　 When the generator housing is vibrated, the magnet will vibrate with a relative amplitude. This relative movement of the magnet results in the varying amount of magnetic flux density cutting through the coil. According to Faraday's law of electromagnetic induction, a voltage is induced in the loop of coil.