Analysis of Output Performance of Airflow Energy Harvester Using Diamagnetic Levitation Based on Taguchi Method

In order to improve the energy harvesting efficiency of airflow energy harvester based on diamagnetic levitation, structure parameters and position relationships between the coils and the floating magnet were investigated theoretically and experimentally. The output performance of the energy harvester was conducted, and the concept of energy conversion factor was proposed and defined. Seven control variables affecting the peak-induced electromotive force generated by the coils were analyzed using the Taguchi method. The result shows that all seven control factors are significantly related to the peak-induced electromotive force. Among them, the percentage contribution of the notch radius of the floating magnet is 69.17%, so it is the most significant factor. Further research on the notch radius of the floating magnet was carried out to obtain the important conclusion that the energy conversion factor is maximum when the ratio of the floating magnet's surface area to the notches' surface area is approximately 2:1. According to the experimental results, for the floating magnet with 9 mm radius, the airflow energy harvester has the maximum energy conversion factor when its notch radius is 3.8 mm, and the variation trend of experimental results is basically consistent with that of simulation results. This study could provide a valuable reference for designing the diamagnetic levitation airflow energy harvester with optimal energy harvesting efficiency.