A high-performance rotational electromagnetic energy harvester based on magnetic plucking: Design, simulation, and experiment

Harvesting rotational energy to supply low-powered electronic devices can optimize the whole power supply system layout. In this paper, we propose a high-performance rotational electromagnetic energy harvester and construct an electro-mechanical dynamic model. The harvester consists of the halbach magnet array (HMA), a radially magnetized cylindrical rotatable magnet, and a copper coil, respectively. The proposed energy harvester is tested in a rotating platform and the correctness of the mathematical model is verified by experimental results. As one of the important components of the harvester, the magnetic field characteristics of the HMA are simulated by the finite element method (FEM) and compared with other magnet arrangements. Additionally, the effect on output when the HMA is rotated individually has also been analyzed. Numerical and experimental results indicate that the rotational energy harvester also has an optimal speed, and the corresponding maximum output power decreases significantly with the increase of the distance between magnets. Numerical results indicate that the maximum power output can be obtained as 516.05 mW at 520 rpm, which is a pretty remarkable result. To verify practical application capability, a rectifier-stable circuit is constructed to light 54 LEDs in experiments.