Lamp ballast having filament heating apparatus for gas discharge lamp
US9013106B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Sep 23, 2011 |
| Grant date | Apr 21, 2015 |
| Priority date | — |
| Expiry date | Sep 6, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B41/295
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Provided is a lamp ballast having a filament heating apparatus for gas discharge lamp, including a PFC converter for receiving an AC input voltage and converting the AC input voltage into a DC bus voltage; an inverter connected to an output end of the PFC converter for converting the DC bus voltage into an AC output voltage for driving gas discharge lamps; and a filament heating apparatus connected to the output end of the PFC converter. The filament heating apparatus includes an auxiliary heating circuit for converting the DC bus voltage into a heating power for pre-heating the filaments of the gas discharge lamps; and a control circuit connected to the inverter and the auxiliary heating circuit for generating an auxiliary voltage according to the heating power to activate the PFC converter. After the auxiliary heating circuit has been operating for a predetermined period of time, the auxiliary heating circuit is turned off first and then the inverter is turned on; or otherwise the inverter is turned on first and then the auxiliary heating circuit is turned off.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.