Reduction of unbalanced armature magnetic flux in segmental rotor fefsm using rotor span refinement

Recently, Field Excitation Flux Switching Motor (FEFSM) using salient rotor has been introduced with their advantages of overlap winding (OW) and controllable field excitation coil (FEC) magnetic flux. Despite the motor has high power and high speed diverse performances, the salient rotor structure is found to lead much longer flux path between stator and rotor producing weak flux linkage along with low torque performances. In this research, a new structure of singlephase FEFSM using segmental rotor with non-overlap windings (NOW) is proposed with clear advantages of less copper losses, light rotor weight and much robust structure. Characteristic performances of the proposed motors such as armature coil and field excitation coil flux linkages, back-emf, average torque, and output power are analysed using JMAG Designer version 15. Ratio of unbalanced armature magnetic flux has also been solved using rotor span refinement. The armature magnetic flux amplitude at positive and negative cycles have been improved by 41.5% and 69.1%, respectively.