Motor control device, motor control method, and motor unit

A motor control method of a motor control device which controls a brushless motor comprising a rotor and a three-phase armature coil of U-phase, V-phase, and W-phase, wherein

• the motor control device comprises:
• a position detection unit which detects a rotational position of the rotor;
• a control unit capable of selecting a first control mode and a second control mode, and which
• outputs, in the first control mode, a first drive signal to an inverter at a current-supply timing based on the rotational position of the rotor, and
• outputs, in the second control mode, a second drive signal to the inverter at the current-supply timing based on the rotational position of the rotor;
• and
• the inverter which outputs, in the first control mode, a first current-supply signal as an applied voltage applied to the three-phase armature coil, and
• outputs, in the second control mode, a second current-supply signal as the applied voltage applied to the three-phase armature coil;
• and
• the control unit performs control in a way that for any two of the three phases, a duty value when a duty of the applied voltages is the same is larger in the second control mode than in the first control mode.