Research on Permanent Magnet Structure of Permanent Magnet Synchronous Motor for Electric Vehicle

The driving motor requirements of electric vehicles are small volume, light weight, high power and high torque density, high overload capacity, high efficiency in a wide speed range, good environmental adaptability, high reliability, low cost and so on. Permanent Magnet Synchronous Motor (PMSM) is famous for its simple structure single, reliable operation, small size, light weight, low inertia and fast response, high power factor and high power density, high efficiency and become the first choice of electric vehicles. The change of permanent magnet (PM) structure in the rotor of PMSM also has great influence on the performance of the motor. PM structures are divided into internal and surface types. Surface-mounted permanent magnets are usually surface structures. Internal permanent magnets are usually available as 1-type, V-type, V+1 type, Double V-type and Inset Radial type. While maintaining the same stator structure and the amount of PM, the PM structure was changed and the performance parameters of these six PM structures were compared. Finally, it is found that V+1 type permanent magnet structure has the best performance under the same cost and is the most suitable PM structure for electric vehicles.