A Wideband Electromagnetic Energy Harvester for Random Vibration Sources

A novel non-resonant energy harveser with wide band frequency is proposed for collecting energy from ambient vibration at low frequency. A free-standing magnet is packaged inside a sealed hole which is created by stacking 5 pieces of printed circuit board (PCB) substrates with multi-layer copper coils made on double-sides. When the energy harvester is shook from 10 to 300 Hz at 1.9g acceleration along longitudinal direction of hole, a 65 Hz flat-band-like output voltage of 4.5 mV at the case of only one side with drilled air holes on acrylic plate is generated within 35 to 100 Hz. The output power from the coils is measured as 0.1µW under matched loading resistance of 50 Ω within this flat band range under 1.9 g ambient vibration.