A magnet-induced buckled-beam piezoelectric generator for wideband vibration-based energy harvesting

作者：Zhu Yang^*; Zu Jean

来源：Journal of Intelligent Material Systems and Structures, 2014, 25(14): 1890-1901.

DOI：10.1177/1045389X14541498

• Piezoelectric energy harvesting
• buckled beam
• magnetic force
• bistable structure
• snap through
• low frequency
• broad frequency bandwidth
• nonlinear vibrations

This article presents a magnet-induced buckled-beam piezoelectric generator developed for broadband vibration-based energy harvesting at low frequencies (<60 Hz) and small excitations (<0.5g). The harvester is made of a clamped-clamped piezoelectric beam, with one end movable and subjected to a magnet-induced compressive force. Due to the magnetic force, the beam becomes buckled and bistable. The harvester works as a double-well potential oscillator under excitations, where large-amplitude inter-well oscillation is produced to enhance the energy harvesting functionality. Numerical simulations show that the proposed harvester exhibits strong nonlinearities under harmonic excitations, including snap-through motions, large-amplitude voltage outputs, and broad frequency bandwidth. A prototype harvester is fabricated and experimentally investigated to confirm the findings from numerical simulations. It is observed that for a small base excitation of 0.35g, the harvester can produce a broad frequency bandwidth of 25.0 Hz (24.0-49.0 Hz) to constantly trigger inter-well snap-through motions and to maintain a peak-to-peak voltage of <10 V over a 1.3 M Omega load resistor. For a relatively larger base excitation of 0.5g, such a frequency bandwidth can be further widened to 29.5 Hz.

• 出版日期2014-9