This paper will compare and analyze an Electrically Excited Synchronous Motor (EESM) and Interior Permanent Magnet (IPM) machines for an electric vehicle application based on Volkwagen ID.3 2020. The Torque and Power performances of EESM can be imporved in wide range of speed with the same machine size and power inverter in compared with the IPM machine. Efficiency maps of both machines are obtained and compared with iron losses calculated by finite element analyses. It shows that the EE machine can be a low-cost alternative to the IPM machine with slightly lower efficiency and maximum torque. Due its adjustable excitation, the EE machine is able to achieve a wider constant power speed range than the IPM machine. However, the efficiency of the EE machine is not better than the IPM machine in the high-speed region, since flux weakening control via armature windings is still necessary.

This paper also presents a detailed design of three-phase interior permanent magnet (IPM) synchronous motors Electrically Excited Synchronous Motor (EESM) with minimum weight, and maximum power output for a wide constant-power range. The stator and rotor geometry of the two motors with several variables and constraints has been implemented to evaluate electromagnetic performances. The proposed motor design is based on both analytical models and special software to determine the magnetic sizes and geometry parameters of the stator and rotor. The experimental test and analytical results have been used to evaluate silicon steel material for designs.