Patent ID: 7728541

Claim:
An electric motor drive control method, comprising: deriving a target current from a target torque to apply electric current corresponding to the target current to an electric motor, wherein: when a rotation speed of the motor is in a predetermined speed region, including a zero rotation speed at which the target current for driving the motor allocated to the target torque is switched discontinuously, the target current corresponding to the rotation speed is obtained through a linear interpolation using the rotation speed and target currents at a traction side and a regeneration side allocated to the target torque such that the electric current corresponding to the target current is applied to the motor, and when the rotation speed of the motor is out of the predetermined speed region, the motor is subjected to the electric current corresponding to the target current that is determined based on the target torque on a high efficiency torque curve that represents respective target currents for generating respective target torques of the motor with minimum power consumption.