A Design of IPMSM for High-Power Electric Vehicles With Wide-Field-Weakening Control Region

The motor in high-power electric vehicle (EV) easily reached the voltage limit because of its large magnetic flux. Therefore, the motor should be designed so that the voltage is controlled at the limit. To achieve well voltage control condition, the interior permanent-magnet synchronous motor (IPMSM) is controlled by the field-weakening control method after the constant torque region. This is conducted by canceling the magnetic flux from the permanent magnet with the magnetic flux of the stator winding. However, this method generates many harmonics. In this article, a design that effectively controls the voltage by reducing the harmonics generated in the field-weakening control is proposed. To reduce the harmonics in the field-weakening region, the change stator and rotor design parameters and the reason for using V-type permanent magnet arrangement for high-speed operation will be elucidated.