Split-phase claw-pole induction machines with soft magnetic composite cores

In this paper, a novel split-phase, claw-pole, induction machine (IM) is proposed. Soft magnetic composite (SMC) material is used in the stator cores. After a description of the machine operating principles, the novel structure of a line start, split-phase, claw-pole, IM is presented, and the novel machine features in terms of efficiency, torque density, harmonics, and cost are discussed. Several topologies are investigated. A 200-Watt prototype is designed and compared to a normal IM with the same power level. It is found that the claw pole IM has comparable material cost to the normal radial flux induction machines with the advantages of several percentage points higher efficiency and much higher torque density. The spatial harmonics are effectively reduced by optimum sizing and shaping of the stator poles.