Bridgeless rotor synchronous reluctance machine design evaluation

Abstract

This study presents a bridgeless rotor (BLR) design for a synchronous reluctance machine (SynRM) as a magnet-free alternative for electric vehicles (EVs). Unlike conventional SynRMs that require radial and tangential bridges for mechanical stability, the BLR-SynRM eliminates these structures and instead uses non-magnetic backplates. This modification addresses a significant performance limitation, resulting in a higher torque density and improved power factor.In this research, the proposed BLR-SynRM design is evaluated in several stages. First, the performance is analyzed, considering that flux guides are spot welded into the backplates to maintain the rotor’s integrity. Next, an electromagnetic design is conducted based on an optimized structure to achieve a substantial increase in both torque and power factor. Finally, the rotordynamics of the system are examined across a full speed range of up to 10,000 rpm.