Motor driving apparatus and controlling method thereof

A motor driving apparatus comprising:

• a motor having a rotor including a permanent magnet, and a stator;
• an inverter configured to supply a driving power to the motor;
• and
• a control unit configured to estimate a parameter using a startup estimation when a rotation speed of the rotor is less than a preset startup speed, configured to estimate the parameter using a driving estimation with a dead time compensation when the rotation speed of the rotor is equal to or greater than the preset startup speed and a torque of the rotor is equal to or less than a preset driving torque, and configured to estimate the parameter using the driving estimation without the dead time compensation when the rotation speed of the rotor is equal to or greater than the preset startup speed and the torque of the rotor exceeds the preset driving torque.

A controlling method of a motor driving apparatus, the method comprising:

• supplying a d-axis test current and a q-axis test current for a predetermined amount of time;
• estimating a parameter based on a d-axis current and a q-axis current of a time when the d-axis test current and the q-axis test current are supplied and a time when the d-axis test current and the q-axis test current are not supplied;
• supplying a step-like composite square wave as a driving current;
• and
• compensating for a dead time based on a polarity of the driving current.

A controlling method of a motor driving apparatus, the method comprising:

• estimating a parameter using a startup estimation when a rotation speed of a rotor is less than a preset startup speed;
• estimating the parameter using a driving estimation with compensating for a dead time when the rotation speed of the rotor is equal to or greater than the preset startup speed and a torque of the rotor is equal to or less than a preset driving torque;
• and
• estimating the parameter using the driving estimation without the compensating for a dead time when the rotation speed of the rotor is equal to or greater than the preset startup speed and the torque of the rotor exceeds the preset driving torque.