Controller for electric motor

A controller comprising:

• a learning control unit for determining learning data based on a positional deviation between a target-position command commanding superimposed-type motion including repetitive motion and a positional fed-back variable obtained from an output portion of an electric motor, storing the learning data, and correcting the positional deviation by using the learning data;
• and
• an operation control section for controlling an operation of the electric motor based on a corrected positional deviation obtained in said learning control unit;
• said learning control unit comprising:
• a first learning section for determining, based on said positional deviation, and storing first learning data in a periodic manner according to a first learning period;
• a learning-data correcting section for correcting said first learning data in a manner as to eliminate an influence of a local change included in at least one of said target-position command and said positional fed-back variable, said local change arising in a periodic manner according to a period different from said first learning period;
• and
• a positional-deviation correcting section for correcting said positional deviation by using corrected learning data obtained by correcting said first learning data in said learning-data correcting section.