Power Density Comparison for Three Phase Non-Slotted Double-Sided AFPM Motors

There are two topologies for non-slotted double-sided axial flux PM (AFPM) motors. The stator of the non-slotted AFPM machine is realized by non-slotted tape wound core with AC polyphase air gap windings and the rotor structure is formed by axially magnetized fan-shaped surface mounted Neodymium Iron Boron (NdFeB) permanent magnets. Selecting an AFPM motors with high power density is an important parameter in applications. So, comparison of power density between different topologies of double-sided AFPM motors seems to be necessary. In this paper, the sizing equations of axial flux non-slotted one-stator-two-rotor (TORUS) and two-stator-one-rotor (AFIR) type PM motors is presented and comparison of the TORUS and AFIR topologies in terms of power density is illustrated. Finally a high power non-slotted double-sided AFPM motor is introduced in the paper