Bemf zero-crossing detection system of a multiple-phase motor
US5909095A · kind A · utility
27Cited by
22References
18Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 31, 1997 |
| Grant date | Jun 1, 1999 |
| Priority date | — |
| Expiry date | Jul 31, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/182
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The invention relates to a method for detecting a threshold-crossing of a back electromotive force (bemf) measured in one phase of a multiple-phase motor, the one phase being set at a high impedance while at least one other phase is supplied by pulse-width modulation signal. The method includes the step of comparing the bemf with a threshold. The method includes, prior to the step of comparing, the steps of sampling the bemf during on-periods of the pulse-width modulation signal, and holding the bemf during off-periods of the pulse-width modulation signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.