Development and Comparative Evaluation of Wound-Field Flux Switching and Flux-Switching Permanent Magnet Machines

Abstract—FSPM and WF-FSM motors hold a critical role in modern electric machine technology. FSPM motors are widely employed in electric vehicles, wind turbines, and high-performance industrial systems due to their high power density, compact design, and superior efficiency. In contrast, WF-FSM motors, with their wound-field rotor structure, provide more precise and flexible torque control, offering low torque ripple, high average torque, and reduced harmonic content, which make them particularly advantageous for applications requiring accurate and stable operation. In this study, the FSPM motor was first designed, and using the same design parameters, a WF-FSM motor was subsequently developed. A parametric analysis was performed in Ansys Maxwell to identify the optimal DC supply current for the WF-FSM motor, which was determined to be 17 A. Based on this current, torque and back EMF waveforms as well as magnetic flux distribution visualizations were obtained for the WF-FSM motor. These results were then employed to perform a comparative evaluation of the performance characteristics of both motors. The analysis revealed that the WF-FSM motor exhibited a more stable operational profile with low torque ripple and high average torque, whereas the FSPM motor showed more pronounced torque fluctuations and higher harmonic content in its back EMF. Additionally, the WF-FSM motor demonstrated superior performance in terms of vibration and mechanical stress. The findings of this study indicate that the WF-FSM motor is a more suitable choice for applications requiring precise and stable motor control, providing valuable insights for motor design optimization and system integration decisions.