A three-dimensional electrostatic/electret micro power generator for low acceleration and low frequency vibration energy harvesting

This paper presents the fabrication and characterization of a novel three-dimensional (3D) electret-based micro power generator, which is capable of converting low acceleration (<;0.05g) and low frequency (<;100Hz) ambient kinetic energy to electrical energy. A localized charging method integrating multiple needles is proposed. The experimental analysis shows that the proposed generator operates an out-of-plane direction at mode I of 66Hz and two in-plane directions at mode II of 75Hz and mode III of 78.5Hz with a phase difference of about 90°. It can be a potential candidate in the development of a 3D vibration energy harvester.