Buck-boost converter with smooth transitions between modes
US8436591B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 24, 2009 |
| Grant date | May 7, 2013 |
| Priority date | — |
| Expiry date | Jul 26, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/1582
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a buck-boost converter, the method compensates for the boost mode power switch having a minimum on-time when entering the buck-boost mode from the buck mode by immediately decreasing a duty cycle of the buck mode power switch upon entering the buck-boost mode. This prevents the inductor current from being higher at the end of the switching cycle than at the beginning of the cycle, so the output voltage stays regulated without the converter oscillating between the buck mode and the buck-boost mode. The duty cycle of the buck power switch is increased in the buck-boost mode as the input voltage further falls and the boost power switch duty cycle is increased. Upon transitioning into the boost mode, the duty cycle of the boost power switch is immediately reduced to compensate for the buck switching being stopped and the buck power switch having a minimum off-time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.