Method and device for estimating the angular position of the rotor of a brushless motor
US7786686B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 22, 2008 |
| Grant date | Aug 31, 2010 |
| Priority date | — |
| Expiry date | Jan 7, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/182
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method is for estimating an angular position of a rotor of a motor having position sensors along the circumference of a stator and generating digital signals that switch each time the rotor crosses certain angular positions. The method includes storing rotor angular positions at every digital signal switching, and determining for each rotor revolution a time interval elapsed between a current and a precedent switching edge of the signal generated. The method also includes estimating the angular position during a current rotor revolution by identifying which position sensor generated the last detected switching edge. The corresponding angular position and the time interval elapsed between two consecutive rotor crossings, through a same angular position, correspond to a sum between the angular position and a product between a fraction of the time interval elapsed from the corresponding precedent switching edge multiplied by 360° and a number of polar pairs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.