Electromagnetic-based bridge energy harvester using traffic-induced bridge's vibrations and ambient wind

This paper presents a novel electromagnetic-based bridge energy harvester (EBEH) utilizing bridge vibrations and ambient wind to harvest energy for wireless sensor nodes (WSNs) used for monitoring the health of bridges. The architecture, working principle, fabrication and characterization of the harvester is discussed. The harvester consists of a fixed wound coil, a permanent magnet, an airfoil, a cantilever beam and a base support. The harvester is characterized both under ambient vibration and wind energies. The EBEH generated an open circuit voltage of about 1 V at resonance and under 1 g base acceleration. However, when a load resistance of 54.5 Ω is connected across its terminals, it produced an rms voltage of 290 mV. Moreover, the harvester delivered a maximum power of 354.5 μW to matching impedance at the first resonant frequency of 3.6 Hz, when provided an excitation level of 0.4 g.