Efficiency Evaluation of Micro Seismic Electret Power Generator T. Tsutsumino*

Efficiency evaluation of a micro electret generator prototype for energy harvesting applications is presented. MEMS-friendly perfluoropolymer, CYTOP is adopted as high-performance electret material. In power generation experiments using a prototype seismic generator, maximum output power of 0.28 mW is obtained with 1.2 mm p-p in-plane oscillation at 20 Hz. Electrostatic force in the in-plane direction is also calculated using one-dimensional electrostatic field model. It is found that the counteracting force with the sinusoidal oscillation is always in the same direction, and its magnitude is almost constant with the order of 0.1 N. Power conversion efficiency is found to be close to unity with the present model