| 摘要 |
An electric power conversion circuit (4) performs PWM control by switching operation using a pulse signal (7A) output from a pulse control unit (7) and outputs AC power to an AC motor (3). At this time, a vector control unit (8) outputs to a pulse stop control unit (9) the phase information (8A) of current calculated on the basis of phase current information (6A) from a phase current detection unit (6). The pulse stop control unit (9) outputs to the pulse control unit (7) a phase pulse stop control signal (9A) generated on the basis of the phase information (8A) of the current. Thereby, the pulse control unit (7) stops the pulse signal (7A) in a prescribed interval with the zero crossing of the current phase for a prescribed phase in the power conversion circuit (4) as the reference point. |
