Design and analysis of a galloping-based piezoelectric energy harvester with coupled magnetism

Wind-induced vibration energy harvesters have attracted increasing attention due to their unique dynamic characteristics and excellent energy harvesting performance. In this study, two types of magnetic energy harvesters, namely the magnetic attraction energy harvester (A-GEH) and the coupled magnetic attraction and repulsion energy harvester (A&R-GEH), were designed and their electromechanical coupling analysis models were established. The results showed that the magnetically coupled energy harvesters can adjust the operating wind speed range and increase the energy harvesting capability by varying the placement of the magnetic poles and the magnetic moment. Furthermore, the established analysis model accurately predicted the results of the wind tunnel experiments. The output power of the energy harvesters was evaluated by illuminating LED bulbs, demonstrating the potential for self-powering small wireless sensors. Under an experimental wind speed of 5.1 m s⁻¹ and a vertical distance Δy = 12 mm between the magnets, the A-GEH and A&R-GEH showed an increase in output power of 356.854% and 365.488%, respectively, compared to a general energy harvester without magnetism. In conclusion, this study provides a framework for the analysis and design of magnetic-coupled wind-induced vibration energy harvesters.