Optimal design of single-phase 12S-6P FEFSM using segmental rotor and non-overlap windings

Recently, a three-phase Field Excitation Flux Switching Motor (FEFSM) using salient rotor has been introduced, suitable for high torque, high power as well as high speed diverse performances due to their advantages of easy rotor temperature elimination and controllable field excitation (FE) flux. However, existing FEFSMs are found to have low torque performance as the salient rotor structure has caused longer flux path, and consequently weak flux linkage. Therefore, a new structure of a single-phase FEFSM using segmental rotor and non-overlap windings is proposed. There are two valuable findings found in this topology, first is less copper loss due to the non-overlap windings between armature and FE coils, and secondly the segmental rotor structure has produces shorter flux path to produce high torque, less rotor weight as well as robust rotor at high speed condition. Flux linkage, back-emf, average torque and output power characteristics of the initial and optimized designs have been investigated and compared using 2D Finite Element Analysis (2D-FEA) through JMAG Designer version 15. Based on the 2D-FEA analysis, the average torque has increased by 81.3% to 1.65 Nm, while the output power of 466.5 W, increased of 68.2%. In conclusions, a FEFSM using segmental rotor and non-overlap windings is considered as the best single-phase motor due to their optimal performances and less copper loss.