ABSTRACT This paper proposes a multi‐stage magnetic gearbox (MSMG) designed for automotive applications. Although traditional magnetic gears offer contactless operation, their single‐ratio nature restricts performance across diverse driving cycles. The proposed architecture overcomes this by providing six distinct gear ratios within an integrated system. To manage frequency‐dependent parasitic losses at high speeds, an adaptive axial magnet segmentation strategy is introduced, scaling from 3 to 10 segments across the stages. The system's electromagnetic and mechanical characteristics are evaluated using 3D finite element analysis (FEA), investigating torque performance, power loss distributions and axial shifting forces. Results demonstrate a peak efficiency of 96.97% in Stage 2, with efficiency remaining above 92.57% even at the highest speed stage (Stage 6). The study confirms that the proposed MSMG provides a high‐torque‐density (229.50Nm/L in Stage 1), high‐efficiency and maintenance‐free alternative to conventional multi‐speed mechanical transmissions. By effectively suppressing eddy current losses through adaptive segmentation, this design ensures robust performance for high‐power propulsion systems.
Hosseini-Fard et al. (Thu,) studied this question.