System to determine solenoid position and flux without drift
US6300733A · kind A · utility
Inventor
Key dates
| Filing date | Feb 21, 2001 |
| Grant date | Oct 9, 2001 |
| Priority date | — |
| Expiry date | Feb 21, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2047/046
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A system for measuring and controlling solenoid armature position. The system determines inductive voltage in the drive winding of the solenoid, integrates that voltage to obtain flux, and uses the current/flux ratio to measure armature position. To overcome integration drift, the current/flux position measure is compared to an independent position measure, this comparison leading to a drift correction. In an embodiment maintaining a servo-controlled position, flux drift causes position drift and current drift, the latter providing an independent measure of position drift and flux drift, permitting drift correction. In a second embodiment, a high frequency component of the drive voltage (possibly from pulse width modulation) and a high frequency current measurement provide the independent measure of position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.