Bistable multiple-mass elecrostatic generator for low-frequency vibration energy harvesting

This paper reports a novel vibration energy harvester (VEH) design consisting of a double-mass contactless frequency-up converter with buckled clamped-clamped beams. The vibration to electricity conversion is performed through a MEMS silicon micro electrostatic vibration energy harvester (e-VEH) based on in-plane gap-closing interdigitated combs. Despite the fact that the converter itself is designed to resonate at 162 Hz, the use of the bistable stage as mechanical exciter allows a gain factor of hundred when converting low-frequency vibrations (20-40 Hz) into electrical energy.