Gas discharge lamp with active crest factor correction
US5892335A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 8, 1997 |
| Grant date | Apr 6, 1999 |
| Priority date | — |
| Expiry date | Apr 8, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B41/28
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A new circuit for the operation of gas discharge lamps via a converter that operates directly off the rectified AC line without reactive filtering and consequently maintains good power factor and low total harmonic distortion while still maintaining an acceptable lamp current crest factor. The converter employs active crest factor correction to control the actual lamp current to a determined peak to RMS value. The design comprises two stages: a first stage with a non-linear input voltage to lamp current transfer function and a second stage having a frequency modulation to lamp current transfer function designed to cancel the first stage's transfer function at a predetermined input voltage and thus maintain constant lamp current during the correction interval.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.