Synchronous motor drive unit and a driving method thereof
US7294988B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 6, 2005 |
| Grant date | Nov 13, 2007 |
| Priority date | — |
| Expiry date | Dec 6, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/72
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A rotary sensor that outputs two analog signals, such as one sine wave and one cosine wave and has multiple periods within one period of the electrical angle of a motor is employed. The motor is energized at each position for a specified length of time upon its startup by using multiple electrical angles corresponding to the multiple candidate absolute angles obtained from the rotary sensor signal as the initial position of the motor, and the electrical angle at which the motor acceleration becomes maximum is determined as the absolute angle. While the motor drive is in operation, on the other hand, the phase difference Δθ between the phase of the motor at the counter electromotive voltage and the control phase is directly computed from the parameters of the motor, sensed current, voltage command and angle speed so as to correct the shifted position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.