Study on Diamagnetic Levitation Structure in Electromagnetic Vibration Energy Harvester

In this paper, we proposed an electromagnetic vibration energy harvester with a diamagnetic levitation structure, which consists of a lifting magnet, two highly oriented pyrolytic graphite (HOPG) sheets, and a floating magnet. The dynamic characteristics of the diamagnetic levitation structure arc critical to the performance of the energy harvester. The diamagnetic and magnetic forces were calculated in COMSOL (TM), and the bistable phenomenon of the diamagnetic levitation structure was found and verified experimentally. The nonlinear characteristics of the diamagnetic levitation structure were studied in Simulink. Under different external excitations, the intrawell and interwell vibrations were observed in phase diagrams. When the excitation frequency is 1 Hz and the amplitude is 8.1 mm. the low-energy region is similar to the high-energy region, which is beneficial to harvest energy.