Comparisons of Permanent-Magnet Machines with Different Rotor Topologies for Quadruped Robot

For quadruped robot, permanent-magnet (PM) machines are competitive due to their promising high torque density. In this paper, four PM motors with fractional-slot concentrated windings (FSCW) are designed and compared. They are designed with the same design specifications but different rotor topologies, including surface-mounted PM (SPM), flat-shape interior PM (F-IPM), V-shape interior PM (V-IPM) and consequent-pole (CP). Electromagnetic performances of these motors are analyzed using finite element method (FEM) and the main concern of this comparison is the electromagnetic torque characteristic. It is proved that SPMSM achieves the highest electromagnetic torque and CP PM motor may become a new option for quadruped robot owing to the better torque performance and less PM material usage compared with IPMSM.