The automobile industry is riding the wave of electrification and is focusing on developing vehicle drive motors. The main goals are small size, light weight, high torque density, low cost, and compatibility with a wide range of operating conditions. In order to meet these requirements, the type of motor installed in a vehicle and its characteristics are important.
Currently, magnet field type AC synchronous motors are commonly used as drive motors for vehicles. This is due to its high maximum efficiency, high power density, and mature technology. However, new field-wound AC synchronous motors are also attracting attention because they can adjust the rotor's magnetic force and can adapt to various operating conditions. However, there is a limit to the miniaturization of the motor, and the efficiency is slightly lower than that of the magnet field type.
