A Novel Coaxial Magnetic Gear With Unequal Halbach Arrays and Non-Uniform Air Gap

In order to improve the output torque and transmission stability of coaxial magnetic gear (CMG), a novel CMG with unequal Halbach arrays of the inner rotor and non-uniform air gap is proposed in this paper. According to the principle of magnetic field modulation and “one-sided flux” structures, the unequal Halbach arrays could augment the magnetic field in the inner air gap. Moreover, the permanent magnets (PMs) of the eccentric structure could obtain non-uniform air gap, which is helpful to enhance the flux-modulation effect. The proposed CMG topology with 4 inner and 17 outer pole pairs is established. The topology performance is assessed and calculated by finite element analysis (FEA).