Apparatus and method for electronic control of DC motor using an all-digital phase-locked loop
US6823133B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 15, 1999 |
| Grant date | Nov 23, 2004 |
| Priority date | — |
| Expiry date | Nov 15, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B2219/41329
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A control system in the form of an all-digital phase-locked loop controls movement of a DC motor. The control system includes a movement detector in the form of an optical encoder to detect movement of a DC motor. A digital phase detector compares output of a feedback signal from the movement detector and a reference signal. The digital phase detector is phase frequency detector that follows a describing function to model non-linear components of the reference signal. A digital loop filter then filters noise from the comparison signal and the filtered signal is amplified to control the DC motor. The phase frequency detector includes a state machine to track a time varying reference signal and selectively output a response to provide for system damping.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.