| 摘要 |
PROBLEM TO BE SOLVED: To realize regenerative operation while ensuring detection accuracy of the rotational position of rotor by performing the regenerative operation for returning power generated in an exciting coil to the power supply side during an interval when an exciting current is not fed to the exciting coil. SOLUTION: Even during an interval when an exciting current is not fed to each exciting coil 25-27, power generated in each exciting coil 25-27 can be regenerated to a smoothing capacitor 31 on the power supply side during commutation spike voltage generating interval and delay interval at the time of determining conduction switching timing. Consequently, rotational position of rotor is detected based on a counter electromotive force induced in each exciting coil 25-27 of a three-phase hybrid stepping motor 28. According to the arrangement, regenerating braking can be performed while ensuring detection of the rotational position of rotor even for a sensorless three-phase hybrid stepping motor 28. |
