A 3D multi-directional and multimodal broadband vibration energy harvester using an L-shaped bending beam

Abstract

A three-dimensional (3D), multi-directional and multimodal broadband vibration energy harvester using L-shaped curved beams is proposed in this paper. The harvester is composed of an L-shaped cylindrical bending beam and a piezoelectric beam. The free ends of the L-shaped bending beam and the piezoelectric beam are respectively fixed with a magnet. These two beams are coupled by nonlinear magnetic force introduced by the two magnets. The results show that the prototype can collect 3D multi-directional broadband vibration energies and has three natural frequencies in 3D directions. Under 5 m/s2 acceleration, the prototype obtains 42.1V, 45.0V and 66.9V peak-peak voltages in the x-direction, y-direction and z-direction respectively, and the widest 3 DB bandwidths in this three directions reach up to 6.4Hz, 6.3Hz and 4.2Hz, respectively.