Digital speed control for a brushless DC motor
US4400654A · kind A · utility
25Cited by
5References
1Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 27, 1981 |
| Grant date | Aug 23, 1983 |
| Priority date | — |
| Expiry date | Mar 27, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P23/22
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A digital control system is provided to regulate the speed of a brushless DC motor via pulse-width modulation. Digital counters are used to measure the difference between the time for a motor revolution and a reference time. This time difference is in turn used to control the time until the application of power during a fixed period. A motor speed decrease increases the difference in time between a motor revolution and the reference time. This decreases the power pulse delay time and results in an increased power-on time to bring the motor back up to nominal speed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.