Method and apparatus for automatic average current mode controlled power factor correction without input voltage sensing
US5920471A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Aug 29, 1997 |
| Grant date | Jul 6, 1999 |
| Priority date | — |
| Expiry date | Aug 29, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P80/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method for preparing power factor control integrated circuits which generate linear pulse width modulation (PWM) waveforms is presented. The method of pulse width modulation waveform generation involves providing a capacitor; fast charging the capacitor; and controlling a discharge rate of the capacitor to ensure a constant switching period and a linear PWM waveform. The method is applicable for any single-phase ac/dc converter topology that performs power factor correction. Unlike conventional techniques which utilize three feedback loops, the method of the present invention reduces the total number of feedback loops to two, eliminates input voltage sensing and achieves the same objective. This method results in significant integrated circuit simplification, such as elimination of multiplier, squarer and divider circuits in the control integrated circuit and reduces the cost of the integrated circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.