Method for controlling brushless d.c. motors and apparatus for carrying out the method
US4760316A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 9, 1987 |
| Grant date | Jul 26, 1988 |
| Priority date | — |
| Expiry date | Jun 9, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/06
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The invention relates to a method for controlling brushless d.c. motors and to a system for controlling such motors, by varying the effective value of current pulses to the phase windings. According to the invention, upon detection of a maximum current state, the effective value of the pulses is decreased by shortening pulses from a given time point within the normally remaining part of the pulses, irrespective of whether the maximum current state ceases during the time that this part of the pulses should have occurred or not. This time point may coincide substantially with the time point at which the state of maximum current was detected or may coincide substantially with the later time point at which the duration of respective pulses exceeds a predetermined minimum value. The next pulse is introduced at the same time point at which it should normally have been introduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.