Device for detection of current or voltage on a PWM driven winding with reduced jitter and related methods
US6420847B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 2000 |
| Grant date | Jul 16, 2002 |
| Priority date | — |
| Expiry date | Sep 28, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/182
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method for detecting a zero-cross event of an induced back electromotive force (BEMF) or of a nullification instant of a periodic current in a PWM driven winding, by circuits generating an analog signal representative of the induced BEMF or of the nullification instant of the periodic current, comparing the analog signal with zero and producing a first logic signal, generating a PWM driving signal, and storing a time between two consecutive zero-cross events, is provided. The method may include storing a time between a last two zero-cross events and synchronizing the PWM driving signal from a last zero-cross event having a duration equal to a difference between an established time based upon the stored time interval and a first time. If a new zero-cross event is not detected within the established time, switching of the PWM driving signal may be disabled for a time having a maximum duration equal to a second time or until a new zero-cross event is detected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.