Electric lamp and discharge devices: systems – Pulsating or a.c. supply – Inductance in the supply circuit
Patent
1994-02-01
1996-04-09
Pascal, Robert J.
Electric lamp and discharge devices: systems
Pulsating or a.c. supply
Inductance in the supply circuit
315289, H05B 4116
Patent
active
055064795
DESCRIPTION:
BRIEF SUMMARY
PRIOR ART
The invention proceeds from a device for operating a gas discharge lamp according to the generic concept of the patent claim. German Offenlegungsschrift 3,929,029 discloses such a device in which a gas discharge lamp is connected to a power supply apparatus via a ballast which contains a reactor. Furthermore, a device for starting the gas discharge lamp is directly connected to the lamp. The reactor contained in the ballast fixes the current flowing when the gas discharge lamp is in operation, for example, or limits at least the current to a prescribed maximum value.
The starting device makes available one or more trigger pulses whose energy must suffice for reliable starting of the gas discharge lamp. In the known device, it cannot be ruled out that a certain portion of the starting power is coupled into the ballast and is therefore no longer available for starting the lamp.
It is the object of the invention to specify a device for operating a gas discharge lamp, in which the starting power applied by a starting device is made available as completely as possible for starting a gas discharge lamp.
SUMMARY OF THE INVENTION
The above object is achieved, according to the invention, by a device for operating a gas discharge lamp having a ballast for the power supply of the lamp, which ballast contains a reactor connector in series with the lamp, and having a starting device connected to the lamp, and wherein the reactor is a saturable reactor whose inductance is reduced by the lamp operating current flowing after starting or ignition of the lamp.
ADVANTAGES OF THE INVENTION
The device according to the invention has the advantage that the starting power of the lamp that is made available by the starting device is made completely available, so that a cost-effective design of the starting device is possible. Electrical components which are contained in the ballast do not need to be designed for the high starting voltages produced during the starting process.
The device according to the invention is particularly suitable for starting high-pressure gas discharge lamps which require a comparatively high starting voltage and a high starting power, especially when the lamp is at operating temperature.
BRIEF DESCRIPTION OF THE DRAWING
The device according to the invention is explained in more detail below with reference to the drawing wherein the FIGURE is a block circuit diagram of the device according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The FIGURE shows a power supply apparatus 10 which provides the voltages and currents required for the power supply of a gas discharge lamp 11. The power supply apparatus 10 is connected to the lamp 11 via a ballast 12.
Provided for starting the lamp 11 is a starting device 14 which transmits a trigger pulse whose voltage and whose energy content suffices for starting the lamp 11. Starting the lamp 11 is triggered by a control device, not shown in the FIGURE, which also controls the power supply apparatus 10, if necessary.
When the starting device 14 transmits one or more trigger pulses, apart from the lamp 11 the ballast 12 is also subjected to corresponding pulses. It is provided according to the invention that the reactor 13 contained in the ballast 12 has a nonlinear characteristic. The reactor 13 is designated below as a saturable reactor. This method ensures an isolation of the starting circuit containing the starting device 14 and the lamp 11 from further electrical components of the ballast 12 and of the power supply apparatus 10 during starting of the lamp. The saturable reactor 13 is to be designed in this case such that for a low current, the maximum of which can be reached during the starting process owing to the short voltage pulse, the inductance assumes a high value which corresponds to the value of the non-saturated reactor. The comparatively high operating current flowing after starting of the lamp is intended, by contrast, to lead to saturation of the reactor 13 and thus to a decrease in its inductance. The supply
REFERENCES:
patent: 3555352 (1971-01-01), Michalski
patent: 3963958 (1976-06-01), Nuckolls
Betz Dieter
Mark Wolfgang
Pascal Robert J.
Robert & Bosch GmbH
Shingleton Michael
LandOfFree
Device for operating a gas-discharge lamp does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device for operating a gas-discharge lamp, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for operating a gas-discharge lamp will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-141119