The cooling system of electric motors plays a critical role in ensuring the performance and reliability of electric vehicles. In this work, three different oil cooling circuit configurations for an Interior Permanent Magnet(IPM)motor were designed and evaluated through CFD simulations. The proposed cases include: (i) coolant flow through a hollow shaft, (ii) cooling channels embedded in both the shaft and rotor laminations, and (iii) an additional cooling channel created by indenting the magnets by 0.5 mm between the shaft and rotor laminations. Considering the anisotropic thermal properties of stator windings, the equivalence of the rotor–airgap region, and the stator waterjacket.