| 摘要 |
PROBLEM TO BE SOLVED: To stably determine the polarity of a magnetic pole of a permanent magnet synchronous motor while the motor stops without using a rotation sensor.SOLUTION: A high-frequency component and a DC bias component, which has a magnitude which causes a motor to be magnetically saturated and take on a certain value Ib over a predetermined period, and is positively and negatively symmetrical, are impressed as an observation command on a d-axis current command. The polarity of the magnetic pole of a permanent magnet is identified based on a relationship of large and small magnitudes between a first amplitude a1 attained during a period during which a DC bias component takes on a positive certain value +Ib among amplitudes of a high-frequency component contained in a d-axis response voltage Vd computed based on a feedback current respondent to the observation command, and a second amplitude a2 attained during a period during which the DC bias component takes on a negative certain value -Ib. |
