Motor control device and electric power steering device

A motor control device for driving a brushless motor, the motor control device comprising:

• a control calculation unit which obtains a phase voltage instruction value showing a phase voltage to be applied to the brushless motor;
• a current detecting unit which detects an electric current which flows into the brushless motor;
• a rotational position detecting unit which detects the rotational position of a rotor in the brushless motor;
• a correction unit which corrects the phase voltage instruction value based on the detection result of the current detecting unit and the detection result of the rotational position detecting unit so that a dependency of a ratio on an electric angle shown by a secondary harmonic component of the ratio concerning the electric angle of the brushless motor, the ratio being a ratio of a q-axis or d-axis component of the electric current, which flows into the brushless motor, to a q-axis or d-axis instruction value;
• and
• a driving unit which drives the brushless motor based on the phase voltage instruction value after the correction by the correction unit.