Design and analysis of a 2D broadband vibration energy harvester for wireless sensors

This paper presents a design for a novel vibration energy harvester using a magnetoelectric (ME) transducer, which is efficiently applicable in two-dimensional (2D) motion and over a range of vibration frequencies. This harvester adopts a circular cross-section cantilever rod to extract the ambient vibration energy because of its ability to host accelerations in arbitrary motion directions. Moreover, the magnetic interactions between the magnets and the ME transducer will lead to the nonlinear oscillation of the rod with increased frequency bandwidth. The influences of the nonlinear vibration factor and magnetic field distribution on the electrical output and bandwidth of the harvester are investigated to achieve optimal vibration energy harvesting performances. The experimental results showed that, the harvester was sensitive to the vibration with arbitrary in-plane directions. With an acceleration of 0.6 g (where g = 9.8 ms−2), it had the working bandwidths of 4.2 Hz, 2.6 Hz, 2.3 Hz, 2.5 Hz and 3.2 Hz, and the output powers of 0.6 mW, 0.49 mW, 0.33 mW, 0.5 mW and 0.56 mW at the in-plane excitation angles of−90°, −45°, 0°, 45° and 90°, respectively.