Operating appliance and an operating method for high-pressure lamps
AssigneePatent-Treuhand-Gesellschaft fur elektrische Gluhlampen mbH
InventorsAndreas Huber, Bernhard Reiter
Life of this patent
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Abstract
A high-pressure discharge lamp (Lp) is fed with a square-wave current from an operating appliance. In order to reduce overshoots during the commutation of the lamp current, the set current value for the regulating device (5, 6) which is contained in the operating appliance is briefly reduced in the area of the commutation.
Claims14
An operating appliance for operation of high-pressure discharge lamps comprising:
- a pulsed power supply (L2, C2, T1, D1, 1), which supplies a power and provides an operating current for a high-pressure discharge lamp (Lp),
- a polarity reversal network (2) via which the high-pressure discharge lamp (Lp) is coupled to the pulsed power supply, having a polarity reversal signal input at which a polarity reversal signal is fed in (10), which controls polarity reversal of an operating voltage for the high-pressure discharge lamp (Lp),
- a control device (4) which provides a switching signal,
- a control input for the pulsed power supply (L2, C2, T1, D1, 1), at which a manipulated variable is fed in, with aid of which the power which is provided by the pulsed power supply (L2, C2, T1, D1, 1) is varied,
- a measurement device (R1) for providing a control variable, which is a measure of the operating current which the pulsed power supply (L2, C2, T1, D1, 1) emits,
- a device (5) for providing a set variable which is a measure of a current set value,
- a regulating device (6, 8) into which the set variable and the control variable are fed and which emits a manipulated variable as a function of the difference between the set variable and the control variable,
- characterized in that the control device (4) contains means which provide a reduction value by which the set variable or the manipulated variable is reduced in synchronism with the switching signal during a reduction.
A method for controlling a high-pressure discharge lamp (Lp), whose polarity is reversed at regular intervals and is regulated by presetting a set value for one operating parameter by means of a manipulated variable value, characterized by the following method steps:
- before reversing polarity of the high-pressure discharge lamp (Lp), reducing the set value or the manipulated variable value by a reduction value,
- waiting for a dwell time (tRZ),
- reversing polarity of the high-pressure discharge lamp (Lp),
- halving the reduction value at least three times in regular (tRI) successive time steps,
- setting the originally predetermined set value.
Dependencies are inferred from the claim text.