Electromagnetic Energy Harvester for Battery-Free IoT Solutions

The massive use of wireless sensors in IoT leads to the necessity to develop a reliable solution for supplying wireless systems by energy harvesting. Generating electrical energy from ambient sources like vibration is still challenging due to the lack of efficiency of existing converters. In this context, this paper presents a battery-free solution to power a Bluetooth board by a low voltage vibration electromagnetic converter as energy source. For that, a passive energy management circuit based on a double stage voltage multiplier is proposed to rectify and improve the energy output level of the converter. Simulation and experimental investigations are conducted. Results have shown that for an electromagnetic converter with an open circuit output voltage equal to 1.8 V peak to peak, the proposed battery-free solution enables to power the Bluetooth board with a DC voltage equal to 2 V.