Impact of Permanent Magnet Aging on the Performance of Synchronous Motors for Traction Applications

With the continuous electrification of the industrial and transportation systems, higher demanding specifications are being imposed on electrical motors, leading to higher degradation due to the aging of their components. This work focuses on the aging impact of permanent magnets in synchronous machines for traction applications. To characterize the aging effects on permanent magnets under typical thermal and magnetic profiles of electrical machines, two different NdFeB samples are aged using experimental procedures. Different from previous research, where only the magnetic operation point is evaluated along the aging stage, a partial BH curve of the permanent magnet is obtained. With this partial BH curve, the evolution of the remanent magnetic flux density and relative magnetic permeability is obtained for different aging stages, and for different temperatures and magnetic points. The results are used to evaluate the impact of PM aging on the nominal performance of a permanent magnet synchronous machine through finite element analysis.