Motor control apparatus and magnetic-pole position detection method therefor

Provided is a motor control apparatus and a control method therefor, wherein robust magnetic-pole position detection is conducted without being affected by magnetic saturation of the motor rotor, using the hysteresis characteristic of the motor. The motor control apparatus is provided with a current profile generator (111) that generates a current profile; a search voltage calculator (110) that calculates a search voltage pulse on the basis of the current profile, and adds the search voltage pulse to a d-axis voltage command; a magnetic-pole position detector (106) that detects the magnetic-pole position of a permanent magnet motor on the basis of the search voltage pulse; a polarity distinguishing-evaluating current calculator (108) that calculates a polarity distinguishing-evaluating current for distinguishing the magnetic-pole polarity of the permanent magnet motor, from a d-axis current value of the motor current detected by synchronizing with the cycle of the PWM control; and a polarity detector (109) that outputs a phase correction amount from the deviation between the polarity distinguishing-evaluating current and the current command.