Control system for electric motor for driving electric vehicle

A control system for an electric motor for driving an electric vehicle comprising lock state judgment means to judge that the electric motor is in a lock state when a state where a rotational speed of a brushless DC motor has a value equal to or less than a set lock start rotational speed while an opening degree of an accelerator is equal to or more than a predetermined judgment opening degree continues during predetermined judgment time and lock time drive current control means to perform such a control as to gradually reduce a drive current of the motor to a lock-time limit value. Thus, when the rotational speed of the vehicle is lowered until the motor gets the lock state while the vehicle is driven in the state where the accelerator is opened with the opening degree being equal to or more than the judgment opening degree, the drive current is decreased whereby a temperature of armature coils is prevented from abnormally rising.