Effect of Rotor Core Shapings and Ribs on the Performance of Reduced Rare Earth Interior Permanent Magnet Synchronous Machines

Multilayer interior permanent magnet synchronous machines (IPMSMs) are preferred for high-speed operations and reducing rare earth magnet materials. The use of a hybrid magnet arrangement in the rotor structure is made possible by the use of multiple layers in the rotor structure. This is particularly significant as the price of rare earth materials is increasing globally. The reduced use of rare earth topologies in the IPMSM is in growing demand. However, challenges associated with the design prospect to meet the required torque-speed characteristics are the same as those of rare-earth-based IPMSM, as well as high efficiency and less core loss. Typically, the air gap is uniform in the case of an IPMSM. This work deals with the effect of rotor core shaping in the stampings of the rotor along the d-axis, q-axis, or both axes in the U-shaped double-layer rotor topology of IPMSM. Further improvement of the performance of the motor impact of rib thickness has also been investigated. Therefore, different possible combinations of rotor core shaping on the rotor have been considered in this work. Simulation studies have been conducted using FE Simulation software, and the results have been reported.