Active snubbing in a discharge lamp ballast
US6054816A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 2, 1997 |
| Grant date | Apr 25, 2000 |
| Priority date | — |
| Expiry date | Jun 2, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/00
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A snubbing network is provided for reducing electromagnetic ("EM") radiation from and power dissipation of a lamp discharge ballast. The snubbing network employs at least one active device. That device being a switch coupled in parallel with the modulating switch within a converter of the ballast. The snubbing switch, in conjunction with a current limiting inductor, and a voltage change rate limiting capacitor serve to substantially eliminate reverse recovery current within a freewheeling diode of the converter prior to closing the larger (modulating) switch. Reducing the reverse recovery current before closing the modulating switch helps minimize power dissipation during switch closure. A benefit of reduced power dissipation is a reduction in EM radiation from the lamp ballast to noise sensitive electronic components placed nearby.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.