A MEMS Energy Harvesting Device for Vibration with Low Acceleration

Abstract

We propose a polymer electret based energy harvesting device in order to extract energy from vibration sources with low acceleration. With MEMS technology, a silicon structure is fabricated which can resonate in 2D directions. Thanks to the excellent mechanical properties of the silicon material, the proof mass could be successfully driven by an external vibrations with acceleration as low as 0.014 g (∼0.14 m/s2). A root mean square (RMS) power output of 1.17 μW under 0.014 g RMS acceleration at 75 Hz is measured when an optimal load of 20.3 MΩ is applied. The frequency response of the device is also studied and a high Q factor of 250 is achieved.