Sensorless vector control method for alternating-current motor and control apparatus therefor
US7423395B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 2, 2003 |
| Grant date | Sep 9, 2008 |
| Priority date | — |
| Expiry date | Sep 1, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P1/029
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
It is the objective of the present invention to provide a sensorless vector control method and a control apparatus, for an alternating-current motor, that can smoothly restart an alternating-current motor in the free running state.According to the present invention, when a current that flows in an alternating-current motor (2) at a restart time 7 the alternating-current motor (2) continuously flows at a designated current level or higher for a designated period of time, it is determined that the rotational direction or the velocity of the alternating-current motor (2) is incorrectly estimated, and a direct current or a direct-current voltage is again applied to again estimate the rotational direction and the velocity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.