Magnetic device for determination of angular position in a multiphase rotary electrical machine
US8952685B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 7, 2009 |
| Grant date | Feb 10, 2015 |
| Priority date | — |
| Expiry date | Jul 26, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D2205/80
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Disclosed is the selecting of the optimum characteristics of a magnetic device producing a sinusoidal signal for determination of angular position in a rotary machine. The device includes a multi-polar magnetic ring which is mobile in rotation around an axis, and creates a variable magnetic field according to an angle of rotation. In close proximity to the magnetic ring, a magnetic sensor is placed in this magnetic field, and generates the sinusoidal signal. The air gap between the sensor and ring is constituted by spacing the sensor by a distance E from the magnetic ring on a radial plane. Optimum performance is achieved when a first ratio e/E of a thickness e of the multi-polar magnetic ring in a direction which is radial relative to the air gap E is between 0.4 and 2.3. A second ratio h/e of a height h of the ring, in a direction which is axial relative to the thickness e, is between 1.5 and 8.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.