Motor control apparatus for controlling motor based on counter-electromotive voltage generated in winding of motor

A motor control apparatus comprising:

• a counter-electromotive voltage determiner configured to determine a counter-electromotive voltage that is generated in a winding of a motor;
• a position determiner configured to determine a rotational position of a rotor of the motor based on the counter-electromotive voltage determined by the counter-electromotive determiner;
• a velocity determiner configured to determine a first velocity, which is a rotational velocity of the rotor, based on a change amount of the rotational position in a predetermined period;
• a controller configured to (i) calculate an average value of a plurality of first velocities determined by the velocity determiner in a state where the motor is controlled so that the rotor rotates with a predetermined velocity, (ii) calculate a difference value between the average value and one of the plurality of first velocities, and (iii) control a driving current flowing in the winding of the motor based on both the difference value and the first velocity determined by the velocity determiner;
• a memory configured to store the difference value calculated by the controller;
• and
• a corrector configured to obtain a second velocity by correcting the first velocity based on the difference value stored in the memory,
• wherein the controller performs feedback control in which the driving current is controlled so that a deviation between an instructed velocity indicating a target velocity of the rotor of the motor and the second velocity is reduced.