Torque Prediction of Magnetic Gear considering 3D Axial Leakage Flux by Equivalent Magnetic Circuit

Since magnetic gears (MGs) can transmit torque without physical contact, which can allow low vibration and noise, and easy maintenance, it has the potential to replace reduction gears in electrical vehicles. In addition, a traction motor can be miniaturized by applying MGs to an electric propulsion system. For these reasons, much research had been conducted on the design of MGs. In the design stage, 2-dimensional (2D) finite element analysis (FEA) and 3-dimensional (3D) FEA can be used, but there are differences in torque between the two methods. Although the 3D FEA can reflect the leakage path of magnetic flux in the axial direction, it requires a lot of computational time. Therefore, in this paper, the correlation method between torque calculated by 2D and 3D FEA using an equivalent magnetic circuit is proposed. The proposed method can predict the accurate torque considering axial leakage flux, thereby reducing the computation time required for the design.