Bandwidth Extension for MEMS Vibrational Energy Harvester using High-Voltage Electret

We report a new method to extend the frequency bandwidth of MEMS vibrational energy harvester. By increasing the potential voltage used to charge the electret film, the bandwidth expands to almost half of the center frequency of resonance, making it possible to effectively generate power from minute mechanical vibrations of 0.1 G or less. As a result, the harvester becomes capable of generating power from frequencies off the resonance.