General Analytical Modeling for Armature Magnetic Field of Equidirectional Toroidal Winding Motor Based on CDMPF Method

This article presents a general analytical model (AM) for the armature magnetic field (AMF) of the novel equidirectional toroidal winding motor (ETWM), employing the proposed conductor distribution magnetic potential function (CDMPF) method. The CDMPF method combines the superposition of line current magnetic potentials with modulation operators to calculate the AMF, accommodating various winding layouts and flexible stator/rotor topologies. Furthermore, the presented AM encompasses various motor types, arbitrary winding phase numbers, arbitrary excitation currents, as well as flexible stator/rotor salient pole types. It elucidates the operational mechanism of the ETWM and offers guidance for its optimization and design. First, the CDMPF method is proposed, derived from the line current scalar magnetic potential calculated by Maxwell equations. Second, the model unification process of the ETWM is outlined, and the general AM of the AMF is established based on the CDMPF method. In addition, the AMF under various ETWM topologies is analyzed based on the proposed general AM and validated using finite-element models. Finally, prototypes of a 3-phase stator salient pole planar linear motor with equidirectional toroidal winding (ETW) and a 3-phase stator small slotted axial flux rotor motor with ETW are manufactured and tested, verifying the accuracy of the proposed AM.