Comparison of Magnet-less and PM Assisted Synchronous Reluctance Motors for Hybrid Electric Vehicle Application

Electric Vehicles (EVs) have several advantages over their counterparts, but the higher initial cost daunts their mass adoption. Hence, it is necessary to improve EV technology to make it more affordable and efficient. The traction motor is one of the significant components in EV. Synchronous reluctance motor is considered an excellent candidate for EV applications, especially in field weakening regions. In this paper, three different synchronous reluctance motor topologies are designed and compared for the required application while keeping the same constraints. The three proposed topologies discussed in this paper are magnet-free synchronous reluctance motor (SyRM), Ferrite permanent magnet assisted synchronous reluctance motor (ferrite PMa-SyRM) and, Nd-Fe-B permanent magnet assisted synchronous reluctance motor (PMa-SyRM). Initially, the design process is carried out for all the motors with the help of the analytical approach. Further, 2-D FEA simulations are carried out for proposed motors. The performance is analysed based on significant parameters like torque, back-emf, air-gap flux density, and mechanical stress analysis. The results lead to the conclusion that ferrite PMa-SyRM is the best motor from an economic and performance perspective.