Harnessing energy from low-frequency vibrations with a magnetic gear-based electromagnetic energy harvester

In recent years, vibration energy harvesting has emerged as a promising solution as sustainable power supply for Internet-of-Things (IoT) sensing and monitoring devices in various sectors. Nevertheless, the practical implementation of vibration energy harvesting encounters challenges, primarily stemming from the unpredictability and low-frequency nature of real-world vibrations. In this work, we introduce a magnetic gear-based electromagnetic energy harvester (MG-EMEH). The MG-EMEH leverages a distinctive magnetic arrangement, enabling it to perform the up-conversion of low-frequency excitations into high-frequency contra-rotating motions for efficient energy harvesting. The magnets are fully utilized for two purposes: formation of magnetic gear and inducing current in coils that are attached to and rotate with one magnet layer. The innovative structural design is based on finite element simulation to provide initial confirmation of its feasibility. An experimental setup is then established to evaluate the performance of the proposed MG-EMEH. The outcomes obtained from both simulation and experiment demonstrate exciting potential of the MG-EMEH for harvesting energy from low-frequency vibrations below 1.6 Hz. The MG-EMEH from this work represents a step forward in vibration energy harvesting by offering a viable solution to the persisting challenge associated with the conversion of unpredictable and low-frequency vibrations, such as human motions and ocean waves, into useable energy source for wearables, medical applications and offshore environmental monitoring.