Patent ID: 6225758
Filing Date: 2001-05-01
Classification: H05B,Y02B

Abstract:
Method for producing pulsed-voltage sequences for the operation of discharge lamps (8) by means of (a) pulsed discharge(s) which is (are) impeded dielectrically, havingan at least partially transparent discharge vessel (9), which is closed and filled with a gas filling or is open and has a gas or a gas mixture flowing through it and is composed of electrically non-conductive material, andelectrodes (10, 11) of a first polarity and of a second polarity, at least the electrodes (11) of one polarity being isolated from the interior of the discharge vessel by means of dielectric material (19),and having the following method steps,providing at least one offset DC voltage (U.sub.DC (t)), the amplitude (U.sub.DC) of the offset DC voltage (U.sub.DC (t)) or, possibly the resultant total amplitude of all the offset DC voltages being deliberately chosen to be at most sufficiently high that the discharge(s) can be extinguished after each voltage pulse and undesirable restriking between the individual voltage pulses is prevented,providing a sequence of voltage pulses (U.sub.p (t)), which are separated from one another by pauses, the polarity of the sequence (U.sub.p (t)) being opposite the polarity of the at least one offset DC voltage (U.sub.DC (t)) with respect to a common potential (3),superimposition the at least one offset DC voltage (U.sub.DC (t)) and the pulsed-voltage sequence (U.sub.P (t)) to form a total voltage (U(t)) in such a manner that the peak values (U.sub.S) of the total voltage (U(t)) correspond to the sum of the respective magnitudes of the peak values (U.sub.DC, U.sub.PS) of the at least one offset DC voltage (U.sub.DC (t)) and of the pulsed-voltage sequence (U.sub.p (t)), that is to say .vertline.U.sub.S.vertline.=.vertline.U.sub.DC.vertline.+.vertline.U.sub. PS.vertline.,applying of the total voltage (U(t)) to the electrodes (10, 11),a portion of the electrical real power injected into the discharge(s) predominantly throughout the duration of the voltage pulses being injected on the basis of the offset DC voltage (U.sub.DC (t)).