A novel magnetic gear with intersecting axes

Compared with mechanical gears, a magnetic gear (MG) has many merits by virtue of its contactless feature, high efficiency and inherent overload protection. In this paper, a novel MG with intersecting shaft axes based on the flux modulation effect is proposed. Compared with previous MGs, the transmission direction of the novel MG can be designed very flexibly and it also has good competitive edge in relation to the use of permanent magnets, which enables it to have a relatively high-torque density. The working principle and performance are validated by an example design using finite element method. The effects of the dimensional parameters on the torque performance are analyzed. It is also verified that the torque density can be further improved by adopting a flux concentration configuration in its rotor design. It is concluded from the torque per unit volume density performance that the novel MG is very promising as a substitute to conventional gears.