Enhanced transverse-flux motor with torus coils

Two of the most important characteristics of electric vehicle motors are low cost and high reliability. Armature windings are difficult to manufacture with automated techniques and are not very reliable. Thus, to obtain a motor with low cost and high reliability, we have investigated a transverse-flux motor (TFM) containing a torus coil. In this study, we propose an enhanced TFM and discuss its principles and basic characteristics. The rotor has circumferential permanent magnets, and the stator has torus coils and axial 9-shaped cores. The stator core is arranged alternately in the circumferential direction, and has a radial and axial air gap. Our analysis confirms that the enhanced TFM produces a high torque per motor volume of 4.74 kN·m/m³.