Design and fabrication of a new micro-power scaled electromagnetic harvester

Abstract

In the present study, a new micro-power scaled electromagnetic (EM) harvester is designed and fabricated. The device has an innovative magnetic flux varying mechanism with two cylindrical Nb magnets and a central core moving inside the magnets back and forth. The system harvest electricity from the linear oscillations by the help of a spring attached at the bottom part of the core. The device requires only one spring and a second linear-laminated core closes the flux outside of the magnets in order to lower the reluctance of the system. The device is 6 cm in length and 2.4 cm in width in cylindrical geometry as a compact and stable geometry. The experimental verifications have proven that it can generate up to U = 7.76 mV output voltage depending on the oscillation frequency. The maximal output power has been measured as P= 32 μW for 44 Hz frequency with the resistive load RL = 0.2 Ohm. The power density p = 1.17 μW/cm3 has been obtained, experimentally.