A motor driving apparatus comprising: an inverter configured to convert a direct current, DC, power into an alternating current, AC, power through a switching operation and to output the converted AC power to a 3-phase synchronous motor; an output current detector configured to detect a phase current flowing through the motor; a controller configured to: - control the inverter, - during a first interval after the motor stops: control a phase current of a predetermined frequency corresponding to one period of rotation of the motor to flow through the motor, estimate a position of the rotor of the motor based on the detected phase current while the controlled phase current of the predetermined frequency flows through the motor, control a d-axis current command value of a first level with respect to a synchronization reference frame to be applied, extract a d-axis current value with respect to the synchronization reference frame from the detected phase current, and characterised by, to: extract a maximum d-axis current value among the d-axis current value, assume that the rotor of the motor is located at a first position corresponding to the maximum d-axis current value, and estimate the first position of the rotor of the motor based on the maximum d-axis current value of the d-axis current extracted during the first interval, and - during a second interval after the first interval: control a phase current of a predetermined level to flow through the motor to align the rotor of the motor at the estimated first position of the rotor of the motor. an inverter configured to convert a direct current, DC, power into an alternating current, AC, power through a switching operation and to output the converted AC power to a 3-phase synchronous motor; an output current detector configured to detect a phase current flowing through the motor; a controller configured to: - control the inverter, - during a first interval after the motor stops: control a phase current of a predetermined frequency corresponding to one period of rotation of the motor to flow through the motor, estimate a position of the rotor of the motor based on the detected phase current while the controlled phase current of the predetermined frequency flows through the motor, control a d-axis current command value of a first level with respect to a synchronization reference frame to be applied, extract a d-axis current value with respect to the synchronization reference frame from the detected phase current, and characterised by, to: extract a maximum d-axis current value among the d-axis current value, assume that the rotor of the motor is located at a first position corresponding to the maximum d-axis current value, and estimate the first position of the rotor of the motor based on the maximum d-axis current value of the d-axis current extracted during the first interval, and - during a second interval after the first interval: control a phase current of a predetermined level to flow through the motor to align the rotor of the motor at the estimated first position of the rotor of the motor. - control the inverter, - during a first interval after the motor stops: control a phase current of a predetermined frequency corresponding to one period of rotation of the motor to flow through the motor, estimate a position of the rotor of the motor based on the detected phase current while the controlled phase current of the predetermined frequency flows through the motor, control a d-axis current command value of a first level with respect to a synchronization reference frame to be applied, extract a d-axis current value with respect to the synchronization reference frame from the detected phase current, and characterised by, to: extract a maximum d-axis current value among the d-axis current value, assume that the rotor of the motor is located at a first position corresponding to the maximum d-axis current value, and estimate the first position of the rotor of the motor based on the maximum d-axis current value of the d-axis current extracted during the first interval, and control a phase current of a predetermined frequency corresponding to one period of rotation of the motor to flow through the motor, estimate a position of the rotor of the motor based on the detected phase current while the controlled phase current of the predetermined frequency flows through the motor, control a d-axis current command value of a first level with respect to a synchronization reference frame to be applied, extract a d-axis current value with respect to the synchronization reference frame from the detected phase current, and characterised by, to: extract a maximum d-axis current value among the d-axis current value, assume that the rotor of the motor is located at a first position corresponding to the maximum d-axis current value, and estimate the first position of the rotor of the motor based on the maximum d-axis current value of the d-axis current extracted during the first interval, and extract a maximum d-axis current value among the d-axis current value, assume that the rotor of the motor is located at a first position corresponding to the maximum d-axis current value, and estimate the first position of the rotor of the motor based on the maximum d-axis current value of the d-axis current extracted during the first interval, and - during a second interval after the first interval: control a phase current of a predetermined level to flow through the motor to align the rotor of the motor at the estimated first position of the rotor of the motor.