PURPOSE: To reduce a current ripple occurring in the case of switching of an excitation phase of an AC servomotor in a control apparatus of the AC servomo tor for controlling a digital current.

CONSTITUTION: A control apparatus comprises excitation phase switching detecting means 4 for detecting a switching of an excitation phase of an AC servomotor 1, and a phase switching compensator 6 for adding a value of the product of a torque command by a multiplier when the excitation phase is switched. By making the rise speed of current of the next phase approach to the fall speed of current of the last phase, a current ripple occurring at switching the excitation phase can be reduced.