The Ferrite Effect on Magnetic Field Distribution with Two Rotors and One Stator Machine Topology

The study of axial flux permanent magnet machine (AFPMM) has been increasingly interesting to develop, since its construction is simple, easy to make, cheap, and portable. The application of NdFeB having high density, widely available in market and low cost maintenance was beneficial as this machine was brushless so that it didn't need routine maintenance. The results of many earlier researchers showed that there are still opportunities to improve engine performance. In this study, ferrite was used to collect and divert the magnetic flux, thereby reducing the magnetic flux leakage. This paper discussed ferrite installation technique in a cylinder and ring shape to direct magnetic flux circulation into closed circuit, and thus it could reduce leakage flux. This technique was performed on two rotors one stator topology using yhe finite element method for magnetic (FEMM) simulation. The simulation result presented magnetic field distribution on coil stator disc (1) without using ferrite having value of B = 364 to 379 mT (2) with ferrite core in coil having value of B = 399 to 419 mT (3) with ferrite core in each stator edges having value of B = 443 to 409 mT, and (4) with ferrite core both in coil and stator edges having the value of B = 467 to 446 mT.