Wound Field Synchronous Machine with Segmented Rotor Laminations and Die Compressed Field Winding

To increase the torque density of salient pole wound field synchronous machines (WFSMs) a high slot fill die compressed field winding is investigated. Increasing the slot fill of the field winding allows, for the same field ampere-turns, either the rotor ohmic losses to be reduced or the cross-sectional area of the coil to be reduced allowing for more iron in the rotor pole or a reduced flux path length reducing the saturation and MMF required to excite the machine. The compressed coils are single solid objects requiring a joint in the rotor lamination to insert them. The electromagnetic optimization, mechanical design, and construction of the segmented rotor laminations, compression die, and prototype eight pole WFSM rotor are presented.