A high performance drive system for electric vehicle

We have developed a high performance drive system which has satisfied high efficiency, small size and high productivity. The traction motor is a simple structure with a cylindrical magnet using a silicone glue. For the field weakening control, the optimal armature reactance Xd is realized. To minimize a current, the torque control method without the voltage margin is adopted. The PWM control method which uses the voltage of a battery effectively is also adopted. In this paper, details of the optimal design of a surface permanent magnet motor and control techniques are explained, and specifications of the system and testing results are described.