A magnetoelectric, broadband vibration-powered generator for intelligent sensor systems

Magnetoelectric (ME) transducers were originally intended for magnetic field sensors but have recently been used in vibration energy harvesting. In order for vibration energy harvesters to be effective over a range of vibration frequencies, recently many technologies have been investigated to broaden the frequency range of the harvesters using piezoelectric, electromagnetic and electrostatic transductions, but few have been studied that use ME transducers. This paper presents a new broadband vibration energy harvester using ME transducer, which takes advantage of multi-cantilever beams and nonlinear behavior of the magnetic force to expand the working bandwidth in ambient low frequency vibration. And a theoretical model is developed to analyze the non-sinusoidal proof mass motion and the electrical-output performances of the harvester. The experimental results show that the harvester has a bandwidth of 5.4 Hz and power density of 0.2–0.56 mW/cm3 over the entire frequency range under an acceleration of 0.2 g (with g = 9.8 ms−2).