Current control loop bias calibration by integration
US7038417B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 23, 2005 |
| Grant date | May 2, 2006 |
| Priority date | — |
| Expiry date | Feb 23, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P23/14
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Ascertaining through integration a bias calibration level for a current control loop of a driver motor of a tape drive. The driver motor includes a current controller having as inputs a demand signal, a bias signal, and a feedback signal. The current controller includes an integrator coupled to the output. The method includes setting the demand signal to a zero current level, setting the bias signal to a level that substantially prevents the integrator from driving itself high, stepping down the bias signal to form a stepped down bias signal, measuring a sense parameter at the output of the current controller, determining whether the sense parameter is high for the stepped down bias signal, and setting the bias calibration level to a level sufficiently above the stepped down bias signal such that the integrator is not driven high when the demand signal is set to the zero current level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.