Circuit arrangement for A.C. operation of high-pressure gas discharge lamps
US5025197A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1985 |
| Grant date | Jun 18, 1991 |
| Priority date | — |
| Expiry date | Mar 5, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/07
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A circuit arrangement for A.C. operation of high-pressure gas discharge lamps comprising a mains alternating voltage source and a high-frequency oscillator (3) supplied with direct current and which produces a high-frequency current through the lamp superimposed on the mains alternating lamp current. The oscillator comprises a high-frequency transformer (7) and a transistor (11) connected in series with the transformer primary (8). The transistor can be periodically switched on an off. A secondary (9) of the transformer is connected in series with the lamp. Losses are reduced if the ratio between the switching-on and switching-off time (duty cycle) of the transistor (11) is chosen so small that the effective value of the high-frequency current coupled into the lamp lies between 0.05 and 5% of the mains alternating lamp current. An auxiliary device (16 to 19, 25) interrupts the periodic switching of the transistor (11) outside the proximity of the zero passages of the mains alternating lamp current.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.