An electromagnetic rotary-translational motion energy harvester enabled by magnetic-regulated magnetic sphere

This paper describes an electromagnetic energy harvester that uses a rotary-translational magnetic regulation system to convert vibration energy into electrical power. The system consists of a springless magnetic sphere multiple rolling in a cavity and multiple magnetic disks evenly embedded in the cavity. Multiple magnetic disks are arranged with alternating magnetic pole shifts, with the goal of modulating the traditional erratic rolling of the magnetic sphere into a multi-circle regular movement with the change of the magnetic disk’s magnetic pole. Faraday’s law is used to create electromotive forces in coils due to the rotating magnetic moment. The output voltages are measured and analyzed using motion and rotation excitation, parallel, and series coil connections. Experiments on the magnetic sphere with and without magnetic regulation are carried out using a manufactured apparatus. The magnetic sphere with magnetic regulation has periodic and regular output characteristics, according to the results of the experiments. A prototype electromagnetic energy harvester can charge a 0.47 F capacitor to more than 0.40 V in less than 450 s under rotating excitation. The device's energy and effective average power are calculated to be 10.62 J and 23.60 mW.