Design Aspects of Conical Coaxial Magnetic Gears

In this paper, a new design of a conical coaxial magnetic gear was proposed. Conical magnetic gears are considered a logical link between the radial- and axial-field coaxial designs. The modeling of magnetic torques based on the 3D finite element method was developed. The design parameter variations of the conical coaxial magnetic gear were determined and discussed. The magnetic torque density was calculated and compared with that of a cylindrical coaxial magnetic gear with the same size and materials used. An optimal cone angle based on the air-gap length was proposed. Multistage conical coaxial magnetic gears were proposed as a sequence of coupled rotors with increased torque density and reduced magnetic reluctance. The proposed conical coaxial magnetic gears are more compact in size and suitable for integration with electrical machines and variable transmissions.