Synchronized minimum frequency pulse width modulation drive for sensorless brushless direct current motor
US8378606B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 26, 2010 |
| Grant date | Feb 19, 2013 |
| Priority date | — |
| Expiry date | Apr 7, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/188
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Drive voltages to a sensorless brushless DC motor are regulated by varying the width of a single drive pulse (PWM pulse) centered in each of the commutation periods. Switching losses are thereby cut to an absolute minimum because there are only two transitions (on and off) in each drive commutation period. Back EMF zero-cross detectors determine the electrical timing relationships during each electrical cycle. Since the PWM drive pulses are always centered in each of the commutation periods, there will always be back EMF available for measurement of “zero-crossings.” A digital device controls power switching transistors to produce one single PWM pulse during each of the commutation periods.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.