Study on mechanical strength of high-speed V-shaped interior permanent magnet rotors
CAO Kanglei
WANG Dongxiong
ZHANG Yao
Abstract：[Objective]To address the low prediction accuracy of mechanical strength caused by the complex structure and stress concentration in the flux barrier region of a V-shaped interior permanent magnet rotor,a high-precision analytical modeling method was proposed,aiming to provide a reference for the structural design of high-speed rotors.[Methods]Firstly,an improved force balance method was proposed.By introducing deformation compatibility conditions and material physical equations,a mechanical analytical model of the V-shaped interior permanent magnet rotor was established,laying the foundation for stress analysis.Secondly,the influence of key structural parameters on the stress concentration factor(SCF)was analyzed using the finite element method.Polynomial fitting was then employed to obtain the SCF functions for the central and bilateral bridge regions,respectively.Subsequently,the geometric coupling effect within the rotor structure was deeply investigated,and the SCF functions were corrected using relevant structural parameters.Finally,a complete analytical model for rotor mechanical strength was developed by integrating the corrected SCF functions with the improved force balance method.The validity of this model was verified through finite element analysis and strength equivalent tests.[Results]The results indicate that the calculations from the established analytical model are in good agreement with both finite element and experimental results,with a maximum relative error of 9.8%,satisfying engineering requirements.Increasing the thickness of the central bridge significantly reduces its own stress and deformation;increasing the width of the bilateral bridges and the V-angle has a secondary effect on reducing stress and deformation;while increasing the thickness of the bilateral bridges is primarily effective in reducing their own stress.
Keywords：Maximum mechanical stressStress concentration factorDeformationV-shaped interior rotorHigh-speed permanent magnet synchronous motor
Publication Date：2026-04-30
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：9( 57-65 )