Comparison of Stress and Deformation Due to Electromagnetic Torque in SynRM with Flux-Barrier and Segmented Rotor

In an application with a high temperature and restricted volume constraints, the synchronous reluctance (SynRM) machine with passive rotor is a prevalent solution. To attain a high torque density, the rotor structure exhibits complex geometry of either flux barrier or segmented rotor to achieve a high saliency ratio. This study evaluates the consequence of having the flux barrier and segmented rotor structure on the stress and deformation of a small SynRM with a rotor diameter measuring 25.24 mm. The analysis is conducted using FE where torsional force and centrifugal for were affected to the rotor structure at a torque of 0.2 Nm and rotational speed of 10,000 rpm. The results show that the centrifugal force is more critical as it generates higher stress for both rotor designs. The flux-barrier rotor experiences less centrifugal-induced stress at 5.46 MPa compared to 10.92 MPa of the segmented rotor. However, both rotors will not suffer from permanent deformation. A hypothetical dimension scale-up indicates that the flux barrier has a higher stress of 547.56 MPa and deformation due to centrifugal force and exceeds the material yield strength at 10 times its current dimension.