Experimental Evaluation of Low-Speed Flux-Focusing Magnetic Gearboxes

Experimental results are presented for three different low-speed flux-focusing magnetic gearboxes. The performance of the magnetic gearbox is compared when utilizing ferrite and NdFeB and also a hybrid design, in which ferrite magnets are used in the inner rotor and NdFeB magnets are used in the outer rotor. The peak torque and efficiency are measured. It is shown that the NdFeB magnetic gearbox has an active torque density of 151 Nm/L.