Design of External Rotor Permanent Magnet Synchronous Reluctance Motor (PMSynRM) for Electric Vehicles

Abstract

In this study, it is aimed to design an external rotor permanent magnet synchronous reluctance motor (PMSynRM) for an electric vehicle (EV). In recent years, developments in EV technology have increased the need for electric motor design. Electric motors designed to be used in EVs are considered to have high efficiency, high torque and high power density in a wide speed range. Considering these situations, one of the recently designed electric motors is the synchronous reluctance motor (SynRM). However, the disadvantage of a synchronous reluctance motor is the torque ripple. In this study, a 2-kW, three-phase, eight-pole, 24-slots hub motor with an external rotor (PM-SynRM) with a rotational speed of 750 rpm is designed. The design was modeled using the finite element method (FEM) and the necessary analysis was performed. When designing the flux barrier Ld/Lq rate was considered. By using permanent magnets in the design of electric motors, torque and efficiency values have been increased. For this reason, in our PMSynRM design, Neodymium Iron Boron (NdFeB) permanent magnet material is placed in the rotor flux barriers to increase torque. In addition, it is aimed to reduce the torque ripples at low speeds by selecting the distributed winding in the stator windings. Simulation results show that high torque is obtained with low torque ripple. In addition, good results were obtained in terms of efficiency, current, speed and power density. © 2021, The Author(s), under exclusive license to Springer Nature Switzerland AG.