Digital method and apparatus for resolving shaft position
US7205916B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 27, 2006 |
| Grant date | Apr 17, 2007 |
| Priority date | — |
| Expiry date | Jan 27, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/485
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An apparatus and method for determining an angular position of a shaft are disclosed, which comprise resolving an excitation signal at an excitation frequency into at least two orthogonal signals, converting the orthogonal signals to a digital estimate, for each of the orthogonal signals, and evaluating an amplitude and a polarity of the orthogonal signals to determine the angular position. The process of converting the orthogonal signals comprises comparing the orthogonal signal to an analog feedback signal to generate a comparison result and incrementally adjusting the digital estimate in response to sampling the comparison result at an estimation frequency. The converting process also includes converting the digital estimate to the analog feedback signal, collecting a digital estimate history at a sample frequency that is a binary multiple of the excitation frequency, and analyzing the digital estimate history to determine the amplitude and the polarity substantially near the excitation frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.