Loss Analysis of Magnetic Gear with Slotted in Magnetic Modulation Ring

In order to improve the operation efficiency of coaxial magnetic gear (CMG), in this paper, a CMG model with slotted in magnetic modulation ring is proposed. In this model, the permanent magnets (PMs) of internal and external rotors are distributed in Halbach array, the inner rotor PMs are equally divided into 3 small pieces, and the outer rotor PMs are equally divided into 2 small pieces. At the same time, the static magnetic modulation ring iron blocks are slotted, each iron block has 3 slots, the width of the slot is 0.4°, and the depth of the single side slot is 1mm. Finally, a two-dimensional model is established, and the eddy current loss and iron loss of the model are optimized, compared with the conventional CMG model, it is found that the changed pattern can increase the internal and external output torque by 4% and 4.12%, respectively. The eddy current loss is reduced by 66.57%, and the iron loss is reduced by 8.9%, which significantly improve the operation efficiency of the CMG.