Electronic control system for a brushless electric motor
US5767639A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 10, 1996 |
| Grant date | Jun 16, 1998 |
| Priority date | — |
| Expiry date | Jul 10, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/20
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A control system for a three phase brushless motor suitable for use in a three and a half inch flexible magnetic disk drive. The control system needs but one Hall effect sensor for providing a rotor position signal indicative of the angular position of the rotor relative to stator windings. Comparators compare the rotor position signal with reference voltages and provide moment signals indicative of the moments the rotor position signal crosses the reference voltage levels. Three phase motor excitation control signals are produced by counters which count clock pulses for preset periods in response to the moment signals. Motor speed is controlled on the basis of not only the actual motor speed but also the phase difference between the clock pulses and a signal indicative of the moments the rotor position signal crosses zero.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.