Motor control method and device for shift-by-wire system

A motor control device for a shift-by-wire system, comprising:

• a switched reluctance (SR) motor configured to generate a driving force for rotating a detent plate to a target position;
• an encoder configured to output a corresponding electrical signal in accordance with rotation of the SR motor;
• and
• a shift-by-wire (SBW) controller configured to set a target position by analyzing a signal from a shift lever sensor that senses a position change of a shift lever, and configured to control operation of the SR motor on the basis of a signal from the encoder such that the detent plate can be rotated toward the set target position,
• wherein the SBW controller includes a plurality of processors programmed to apply a current to the SR motor when a request for changing a shift range is input by a driver operating the shift lever, to count time from a point in time when the current is applied to a point in time when an actual motion of the SR motor is sensed, to perform advanced-angle control of increasing a rotation speed of the SR motor when the counted time exceeds a preset time reference value, to measure a current that is applied to the SR motor in an actual shifting period in which the SR motor is rotated toward a target position, and to increase the advanced-angle control or perform retarded-angle control of decreasing the rotation speed of the SR motor, depending on the measured current value.