Comparative analysis of winding and flux-barrier configurations on the torque profile of a synchronous reluctance motor

Synchronous reluctance motors (SynRMs) have recently gained attention as a high-efficiency alternative to induction motors (IMs) in industrial applications. While IMs are valued for their robustness and simplicity, their efficiency is limited by rotor copper losses. In contrast, SynRMs employ a laminated iron rotor without windings or permanent magnets, eliminating rotor copper and magnet-related losses and thereby improving efficiency, thermal performance, and reliability. However, their widespread adoption is hindered by high torque ripple resulting from rotor magnetic anisotropy and spatial harmonics produced by the stator winding. This paper presents a comparative investigation of twelve SynRM configurations obtained by combining different stator winding-layer and rotor flux-barrier-layer arrangements. Finite element method (FEM) simulations are performed to evaluate the electromagnetic performance of each design, followed by harmonic analysis of the developed torque. Among the investigated configurations, the W3L-4FB topology achieves the lowest torque ripple of approximately 11% while maintaining an average torque of about 5.1 Nm. Considering both electromagnetic performance and manufacturing simplicity, the W1L-4FB configuration is selected for prototyping. Furthermore, applying a 10° rotor skew reduces the torque ripple to below 3% with only a minor reduction in average torque. Experimental measurements closely agree with the FEM predictions, confirming the accuracy of the proposed design methodology and demonstrating an effective approach for achieving low-torque-ripple SynRMs without sacrificing practical manufacturability.