Coupled Problem Study with Structural Analysis Considering Barrier Filling of PMa-SynRM for Railway Vehicle

This paper investigates the structural-electromagnetic coupled problem of a permanent magnet assisted-synchronous reluctance motor (PMa-SynRM) for railway vehicles considering the barrier filling. The PMa-SynRM is suitable as a traction motor for railway vehicles but is vulnerable to the structural stability of the rotor under centrifugal force. Therefore, the structural characteristics of the PMa-SynRM should be considered, and the structural influences on the electromagnetic performance are also important based on the stress-dependent properties of the electrical steel core. To improve the structural stability, the concept of barrier filling is proposed, which involves inserting a substance into the magnetic flux barrier region of the PMa-SynRM and balancing the loads in the rotor core. The structural analysis results with the barrier fillings are compared for a wide range of their physical properties. We input stress and strain data by element into the rotor electrical steel core of the electromagnetic model, which consists of the identical mesh as the rotor structural analysis results and set conditions to reflect the stress-dependent B-H and iron loss data to analyze the electromagnetic performance including coupled effects. Finally, the best filling substance is derived and applied based on the previous structural analysis results, clarifying the improvement in the structural and electromagnetic characteristics.