To provide a motor drive device that is capable of detecting power failure on an AC power supply side also during a rectifier regenerative operation to thereby preclude erroneous detection of power failure.
A motor drive device 1 includes: a rectifier 11 that converts an alternating current supplied from an AC side into a direct current and converts a direct current supplied from a DC side into an alternating current; an inverter 12 that converts a direct current outputted from the rectifier 11 into an alternating current, supplies the alternating current to a motor 2, converts regenerative electric power from the motor 2 into a direct current, and returns the direct current to the rectifier 11; a DC voltage detection part 21 for detecting a DC output voltage of the rectifier 11; an AC voltage detection part 22 for detecting an AC output voltage of the rectifier 11; a frequency calculation part 23 for calculating a frequency of the detected AC voltage; a storage part 24 for storing, as a reference value, a DC voltage detected at a point of time of start of a regenerative operation of a 120-degree energization type rectifier 11; and a power failure determination part 25 for, during a period of the regenerative operation of the 120-degree energization type rectifier 11, determining presence or absence of power failure on an AC side of the rectifier 11 using the detected DC voltage, the reference value, and the calculated frequency of the AC voltage.
| JPS63265585 | DRIVING CONDITION DECIDING DEVICE FOR SINGLE-PHASE INDUCTION MOTOR |
| JP2717468 | INVERTER |
OKITA HAJIME
NIWA SHOICHI
| JP2006054947A | 2006-02-23 | |||
| JPH1169846A | 1999-03-09 | |||
| JP2006158155A | 2006-06-15 | |||
| JP2001169554A | 2001-06-22 |
Jun Tsuruta
Tomohiro Minamiyama
Akira Kawai
Kenichi Nakamura