The design of a motor with a large armature reaction, such as the electric vehicle traction motor, can be implemented using a trial-and-error method based on the finite element method (FEM). The base model-design method that uses conventional magnetic equivalent circuits is quite inaccurate. To avoid such inaccuracy, this study proposes a method that accurately calculates the inductance values at a practical operating point considering the control issue. To achieve this objective, the flux linkage due to the current phase angles in each section is modeled using magnetic equivalent circuits. The result is used to calculate the inductance, assuming relative permeance waves. Finally, the validity of this study is verified by FEM simulation and testing.