Characterization of electric motor drives for traction applications

The ideal characteristics of an electric motor drive for traction application in an electric and hybrid electric vehicle are high torque at low speed region for fast acceleration, hill climbing and obstacle negotiation, and low torque at high speed for normal driving. To minimize the power rating of the motor drive, therefore, the energy storage power rating, at the given vehicle performance, the electric motor drive is required to have a long constant power range to meet the torque and speed demand. In this paper, the effect of the motor characteristics on the vehicle performance is analyzed, and the characteristics of three major electric motors-induction motor, permanent magnet brushless DC motor and switched reluctance motor are investigated.