Method of estimating initial pole position of permanent magnet brushless motor
US6184647A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 1999 |
| Grant date | Feb 6, 2001 |
| Priority date | — |
| Expiry date | Dec 20, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/28
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In order to estimate a magnetic pole position of a permanent magnet type brushless motor, the following steps are conducted. A given .gamma. axis and a given .delta. axis in an advanced from the .gamma. axis by an electrical angle of 90.degree. are set. A closed-loop electric current control system in the .gamma. axis direction is formed while forming an open-loop electric current control system in the .delta. axis direction. It is calculated an interference current generating in the .delta. axis direction when a current command in the .gamma. axis direction is given as a stepwise alternating current command. The .gamma. axis is finely advanced by an angle of .DELTA..theta. when a sign of a product of an integral value of the interference current and a value of the current command in the .gamma. axis direction is positive. Alternatively, the .gamma. axis is finely delayed by an angle of .DELTA..theta. when the sign is negative. Thereby, the .gamma. axis is made accord with either a d axis as a true magnetic axis or with a -d axis advanced by 180.degree. from the true magnetic axis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.