Comparison of Dual-Stator Permanent Magnet Machines with Different Rotor Topologies

In this paper, three types of dual-stator permanent magnet (DSPM) machines are proposed and investigated, which have two sets of armature windings in both inner/outer stator and produce more than one torque component compared with single-stator PM machines. The power equations and rotor topologies of three DSPM machines are introduced firstly. Next, based on finite-element (FE) method, both the electromagnetic performances of three machines under open-circuit and rated-load conditions after optimization are compared, which aims to generate maximum torque at fixed copper loss. The FE results show that the dual-stator consequent-pole permanent magnet (DSCPPM) machine generates maximum torque per PM volume, together with relatively high efficiency, which make it a potentially hopeful candidate for low-speed and high-torque applications. Finally, a prototype DSCPPM machine has been manufactured and experimentally tested to verify the FE results.