Improvement of the Mechanical Strength of High Speed Synchronous Reluctance Machines by Fiber Reinforced Support Structures

Synchronous reluctance machines (SynRM) are gaining interest due to the absence of permanent magnet and copper in the rotor. However, the mechanical strength at high rotational speed limits the applicability of SynRM in automotive industries. In this work, a fiber reinforced support structure is developed to replace the traditional iron ribs for SynRM for increasing the mechanical strength. Based on a conventional SynRM, a novel rotor is electromagnetically and mechanically designed and optimized with the goal of improving the maximum rotational speed without an impairment of the electromagnetic properties. To prove the proposed concept, a prototype is built and analyzed by mechanical burst tests, as well as electromagnetic measurements. Finally, the simulation results are experimentally validated and it is shown that the rotational speed of 11 000 rpm can be achieved by the new design without negative effects on the electromagnetic properties.