This paper presents the design investigation and experimental testing of a flux-focusing magnetic gearbox with a fully laminated rotor structure. The unique feature of this flux-focusing magnetic gearbox design is that the three rotors are each made of a single lamination stack, and the central modulation structure is retained in place without the use of a resin filler such as epoxy. Ferromagnetic bridges are used to connect individual pole pieces together. It is shown that the use of the ferromagnetic bridges reduces the calculated torque density from 156 Nm/L to 139 Nm/L (a reduction of 11%). The experimentally measured torque density is, however, only 97 Nm/L. The reason for this discrepancy is associated with the demagnetization of the magnets.
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