Electric lamp and discharge devices: systems – Periodic switch in the supply circuit – Impedance or current regulator in the supply circuit
Patent
1992-04-10
1993-03-09
Mis, David
Electric lamp and discharge devices: systems
Periodic switch in the supply circuit
Impedance or current regulator in the supply circuit
315219, 315278, 315282, 315291, 315DIG4, H05B 4129, H05B 41391
Patent
active
051928965
ABSTRACT:
A low cost, high efficiency, dimmable electronic ballast for gas discharge lamps which can be controlled by a traditional phase controlled dimmer is disclosed. This ballast includes a push-pull, parallel resonant, self-oscillating inverter which is comprised of a DC base drive circuit and an adjustable, loosely coupled (between the primary and the secondary) transformer with a pair of magnetic shunts, and a LC filter which has both common and differential mode filter functions to reduce the high frequency interference and improve the power factor. The Q factor of the LC filter will maintain a nearly constant lamp current at low light levels. Wide range dimming (100% to less than 1%) is achieved. A delay start circuit and an overvoltage (open circuit) protection circuit are connected to the LC filter. The overvoltage protection circuit can be connected to either the AC side or DC side of the ballast. The circuit of the invention is capable of removing the striation effect in gas discharge lamps that typically occurs at low light levels.
REFERENCES:
patent: 4350933 (1982-09-01), Agarwala et al.
LandOfFree
Variable chopped input dimmable electronic ballast does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Variable chopped input dimmable electronic ballast, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Variable chopped input dimmable electronic ballast will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-212783