Comparative Study of Non-Rare-Earth and Rare-Earth PM Motors for EV Applications

Recently, non-rare-earth motors are attracting more and attention due to the booming of electric vehicle (EV) market and, importantly, increasing price rare-earth magnet material. This paper focuses on performance comparison among a commercial interior permanent (IPM) motor two motors, including synchronous reluctance (SynRM) permanent-magnet-assisted (PMaSynRM). The design procedure develop high-torque-density, low-torque-ripple high-efficiency SynRM is presented. Combined with developed automatic modeling simulation procedure, finite element analysis (FEA)-based differential evolution (DE) algorithm introduced for rotor optimization. In order fully inspire potential SynRM, novel method optimize split ratio proposed under constraint copper loss. addition, different slot–pole combinations investigated maximize torque, structure also dealt towards centrifugal stress at maximum operating speed. Finally, carried out, results show that although achieves almost 61% cost savings, its poor torque capability, power factor flux weakening (FW) capability non-negligible defects. On contrary, PMaSynRM exhibits excellent features EV applications in terms cost, density, efficiency FW capability. presents optimization optimal SynRM/PMaSynRM demonstrates characteristics IPM SynRMs PMaSynRMs applications.