Fatigue simulation method study on rotor punchings of a permanent magnet synchronous motor
YU Chunxiang
PENG Guomin
GUO Feng
Abstract：In order to solve the fatigue fracture fault in the rotor punchings of an electric drive unit(EDU)assembly,a finite element model of the punchings is established to simulate the fatigue fracture phenomenon of the rotor punchings.The influence of punching thickness,punching material anisotropy,adhesive material,electromagnetic force,uneven contact between magnetic steels and punchings,temperature and other factors on punching stress are analyzed.The S-N curve of the material is refined based on stress test results.The rotor punching structure is optimized,the thickness of the intermediate magnetic bridge and the fillet radius at the fracture point are increased,and simulation and durability testing are conducted to verify the optimization scheme.The results show that the punching stress decreases continuously with the increase of punching thickness,and significantly increases with the increase of uneven contact between the magnetic steels and punchings.The influence of material anisotropy,adhesive,and electromagnetic force on the stress of the polarizer are relatively small,while temperature has a greater impact on the punching stress.After correcting the S-N curve of the material,the fatigue life simulation results are highly consistent with the experimental results,verifying the accuracy of the model.The simulated fatigue life of the optimized solution is 2.18 million cycles,far exceeding the requirement of 30 000 cycles,and has been verified by durability tests.This method successfully solve the problem of punchings fracture and improved the accuracy of punching fatigue life prediction.
Keywords：EDU assemblypermanent magnet synchronous motorpunchingstress analysisfatigue analysis
Publication Date：2025-11-30
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：7( 71-77 )