Micro-Engineered Devices for Motion Energy Harvesting

Published versio

Continuously Rotating Energy Harvester with Improved Power Density

Published versio

CMOS Buck-Boost Power processing circuitry for powerMEMS generators

Accepted versio

Mems inertial power generators for biomedical applications

Accepted versio

Power processing circuits for electromagnetic, electrostatic and piezoelectric inertial energy scavengers

Accepted versio

Simulation toolkit for energy scavenging inertial micro power generators

Published versio

Transduction Mechanisms and Power Density for MEMS Inertial Energy Scavengers

Accepted versio

A micro electromagnetic generator for vibration energy harvesting

Vibration energy harvesting is receiving a considerable amount of interest as a means for powering wireless sensor nodes. This paper presents a small (component volume 0.1 cm3, practical volume 0.15 cm3) electromagnetic generator utilizing discrete components and optimized for a low ambient vibration level based upon real application data. The generator uses four magnets arranged on an etched cantilever with a wound coil located within the moving magnetic field. Magnet size and coil properties were optimized, with the final device producing 46 µW in a resistive load of 4 k? from just 0.59 m s-2 acceleration levels at its resonant frequency of 52 Hz. A voltage of 428 mVrms was obtained from the generator with a 2300 turn coil which has proved sufficient for subsequent rectification and voltage step-up circuitry. The generator delivers 30% of the power supplied from the environment to useful electrical power in the load. This generator compares very favourably with other demonstrated examples in the literature, both in terms of normalized power density and efficiency