EP0459127A1 - High power radiation device with power supply - Google Patents

High power radiation device with power supply Download PDF

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Publication number
EP0459127A1
EP0459127A1 EP91106024A EP91106024A EP0459127A1 EP 0459127 A1 EP0459127 A1 EP 0459127A1 EP 91106024 A EP91106024 A EP 91106024A EP 91106024 A EP91106024 A EP 91106024A EP 0459127 A1 EP0459127 A1 EP 0459127A1
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EP
European Patent Office
Prior art keywords
radiator
power
power supply
converter
frequency
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP91106024A
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German (de)
French (fr)
Inventor
Ulrich Dr. Kogelschatz
Thomas Müller
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ABB Asea Brown Boveri Ltd
ABB AB
Original Assignee
ABB Asea Brown Boveri Ltd
Asea Brown Boveri AB
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ABB Asea Brown Boveri Ltd, Asea Brown Boveri AB filed Critical ABB Asea Brown Boveri Ltd
Publication of EP0459127A1 publication Critical patent/EP0459127A1/en
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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B41/00—Circuit arrangements or apparatus for igniting or operating discharge lamps
    • H05B41/14—Circuit arrangements
    • H05B41/24—Circuit arrangements in which the lamp is fed by high frequency ac, or with separate oscillator frequency

Definitions

  • the invention relates to a high-power radiator with a discharge space, which is at least bounded on one side by a dielectric, which is filled with a gas which emits radiation under discharge conditions, and a power supply device for supplying the discharge.
  • the increasing use of high-performance emitters for exposure, coating and drying processes requires powerful, yet economical power supplies for feeding the discharge.
  • the previous power supply facilities used those that have long been known to ozone generators. Apart from the ozonizers operated at mains frequency, these consist of a converter with controllable frequency, amplitude and / or curve shape of the converter output voltage and a complex high-voltage transformer at the converter output. It has the task of raising the output voltage of the converter, which is at most a few kV, to values that are sufficient to keep the discharge going or to ignite it in the first place.
  • the power supply devices of high power radiators place similar demands on the frequency and amplitude of the voltage supplying the discharge, the operating frequency can be much higher than with an ozonizer. Examples of such radiators can be found in EP-A-0254 111 ... However, the voltage level can be lower, but is regularly above the values (typically around 5 kVolt) that a technically and economically designed converter can deliver able.
  • the object of the invention is to provide a high-power radiator with a power supply device which does not require a complex converter and without a high-voltage transformer.
  • the radiator is connected directly to the converter output with the interposition of an inductor, and this inductance is dimensioned such that it forms a series resonant circuit together with the radiator, which essentially represents a capacitive load, which approximately corresponds to its resonant frequency is coordinated so that a voltage increase of at least 5 occurs at the electrodes of the radiator.
  • the radiator represents by connecting an additional capacitance in parallel.
  • This additional capacity which in principle only the capacity of the extinguished radiator is increased and at the same time serves as an energy store for the ignition phase of the radiator.
  • the frequency of the feeding current or the series inductance could also be changed after the emitter has been ignited.
  • a UV high-power radiator is generally designated by the reference number 1 and the associated power supply device by 2.
  • This power supply device hereinafter generally referred to as "converter”
  • the radiator 1 essentially consists of a closed discharge space 3 which is filled with a gas or gas mixture which emits UV radiation under discharge conditions. Examples of such filling gases are listed in the patent document mentioned at the beginning.
  • the discharge space 3 is delimited on both sides by UV-permeable dielectrics 4 and 5, for example made of quartz glass, to which outer, UV-transparent electrodes 6 and 7 are applied.
  • the electrode 7 is direct, the electrode 6 is connected via an inductor 8 to the two connections of the converter 2.
  • An additional capacitance 9 can be connected in parallel to the radiator 1.
  • FIG. 2 and 3 illustrate the influence of the frequency on the voltage increase (Fig. 2) or the power factor (Fig. 3) for a radiator that was fed from a frequency generator with a downstream power amplifier with a voltage of 130 V eff and had a discharge gap of 3 mm and quartz dielectrics 4 and 5, each 1.5 mm thick, with a dielectric constant of 3.7.
  • Curves A represent the theoretical course
  • curves B the measured course.

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  • Oxygen, Ozone, And Oxides In General (AREA)
  • Treatments Of Macromolecular Shaped Articles (AREA)

Abstract

The use of an expensive high-voltage transformer between the converter (2) and the radiating device (1) for supplying power to high-power radiating devices can be dispensed with if the supply and the radiating device are designed such that a voltage increase occurs on the radiating device which is adequate to start the discharges. <IMAGE>

Description

TECHNISCHES GEBIETTECHNICAL AREA

Die Erfindung bezieht sich auf einen Hochleistungsstrahler mit einem zumindest einseitig von einem Dielektrikum begrenztem Entladungsraum, der mit einem Gas gefüllt ist, das unter Entladungsbedingungen Strahlung aussendet, und einer Stromversorgungseinrichtung zur Speisung der Entladung.The invention relates to a high-power radiator with a discharge space, which is at least bounded on one side by a dielectric, which is filled with a gas which emits radiation under discharge conditions, and a power supply device for supplying the discharge.

TECHNOLOGISCHER HINTERGRUND UND STAND DER TECHNIKTECHNOLOGICAL BACKGROUND AND PRIOR ART

Die zunehmende Verwendung von Hochleistungsstrahlern für Belichtungs-, Beschichtungs- und Trockungsprozesse erfordert leistungsfähige, gleichzeitig wirtschaftliche Stromversorgungen zur Speisung der Entladung. Bei den bisherigen Stromversorgungseinrichtungen wurde auf solche zurückgegriffen, wie sie bei Ozonerzeugern seit langem bekannt sind. Sieht man von den mit Netzfrequenz betriebenen Ozonisatoren ab, so bestehen diese aus einem Umrichter mit steuerbarer Frequenz, Amplitude und/oder Kurvenform der Umrichterausgangsspannung und einem aufwendigen Hochspannungstransformator am Umrichterausgang. Dieser hat die Aufgabe, die in der Grösse von höchstens wenigen kV liegende Ausgangsspannung des Umrichters auf Werte anzuheben, die ausreichen, die Entladung in Gang zu halten bzw. sie überhaupt erst zu zünden.
Die Stromversorgungseinrichtungen von Hochleistungsstrahlern stellen ähnliche Anforderungen an Frequenz und Amplitude der die Entladung speisenden Spannung, wobei die Betriebsfrequenz weit höher liegen kann als bei einem Ozonisator. Beispiele von derartigen Strahlern finden sich in der EP-A-0254 111... Die Höhe der Spannung kann dabei jedoch kleiner sein, liegt aber regelmässig über denjenigen Werten (typisch um 5 kVolt), die ein technisch und wirtschaftlich ausgelegter Umrichter zu liefern in der Lage ist.The increasing use of high-performance emitters for exposure, coating and drying processes requires powerful, yet economical power supplies for feeding the discharge. The previous power supply facilities used those that have long been known to ozone generators. Apart from the ozonizers operated at mains frequency, these consist of a converter with controllable frequency, amplitude and / or curve shape of the converter output voltage and a complex high-voltage transformer at the converter output. It has the task of raising the output voltage of the converter, which is at most a few kV, to values that are sufficient to keep the discharge going or to ignite it in the first place.
The power supply devices of high power radiators place similar demands on the frequency and amplitude of the voltage supplying the discharge, the operating frequency can be much higher than with an ozonizer. Examples of such radiators can be found in EP-A-0254 111 ... However, the voltage level can be lower, but is regularly above the values (typically around 5 kVolt) that a technically and economically designed converter can deliver able.

KURZE DARSTELLUNG DER ERFINDUNGSUMMARY OF THE INVENTION

Ausgehend vom Stand der Technik liegt der Erfindung die Aufgabe zugrunde, einen Hochleistungsstrahler mit einer Stromversorgungseinrichtung anzugeben, welche ohne einen aufwendigen Umrichter und ohne Hochspannungstransformator auskommt.Starting from the prior art, the object of the invention is to provide a high-power radiator with a power supply device which does not require a complex converter and without a high-voltage transformer.

Diese Aufgabe wird erfindungsgemäss dadurch gelöst, dass der Strahler unter Zwischenschaltung einer Induktivität unmittelbar am Umrichterausgang angeschlossen ist und diese Induktivität so bemessen ist, dass sie zusammen mit dem Strahler, der im wesentlichen eine kapazitive Last darstellt, einen Serienresonanzkreis bildet, der annähernd auf seine Resonanzfrequenz abgestimmt ist, so dass an den Elektroden des Strahlers eine Spannungsüberhöhung von mindestens 5 auftritt.This object is achieved according to the invention in that the radiator is connected directly to the converter output with the interposition of an inductor, and this inductance is dimensioned such that it forms a series resonant circuit together with the radiator, which essentially represents a capacitive load, which approximately corresponds to its resonant frequency is coordinated so that a voltage increase of at least 5 occurs at the electrodes of the radiator.

Auf diese Weise lassen sich handelsübliche Stromversorgungseinrichtungen, vorzugsweise Schaltnetzgeräte oder Frequenz-Generatoren mit nachgeschaltetem Leistungsverstärker, mit Ausgangsspannungen um 500 Volt verwenden.In this way, commercially available power supply devices, preferably switched-mode power supplies or frequency generators with a downstream power amplifier, can be used with output voltages of around 500 volts.

Es ist vorteilhaft, die praktisch rein kapazitive Last, welche der Strahler darstellt, durch Parallelschalten einer Zusatzkapazität noch zu vergrössern. Auf diese Weise wird erreicht, dass sich die wirksamen Kapazitäten des gezündeten Strahlers und des ungezündeten Strahlers nur wenig voneinander unterscheiden. Diese Zusatzkapazität, welche im Prinzip nur die Kapazität des gelöschten Strahlers vergrössert, dient gleichzeitig als Energiespeicher für die Zündphase des Strahlers.
Anstelle einer Zusatzkapazität könnte auch nach Zündung des Strahlers die Frequenz des speisenden Stromes oder die Serieninduktivität verändert werden.It is advantageous to increase the practically purely capacitive load which the radiator represents by connecting an additional capacitance in parallel. In this way it is achieved that the effective capacities of the ignited radiator and the non-ignited radiator differ only slightly from one another. This additional capacity, which in principle only the capacity of the extinguished radiator is increased and at the same time serves as an energy store for the ignition phase of the radiator.
Instead of an additional capacity, the frequency of the feeding current or the series inductance could also be changed after the emitter has been ignited.

Die Erfindung wird nachstehend anhand eines in der Zeichnung dargestellten Ausführungsbeispiels näher erläutert.The invention is explained below with reference to an embodiment shown in the drawing.

KURZE BESCHREIBUNG DER ZEICHNUNGENBRIEF DESCRIPTION OF THE DRAWINGS

In der Zeichnung zeigt

Fig.1
in schematisierter Form einen UV-Hochleistungsstrahler mit Stromversorgungseinrichtung;
Fig.2
eine graphische Darstellung zur Verdeutlichung der Spannungsüberhöhung am Strahler als Funktion der Frequenz;
Fig.3
eine graphische Darstellung zur Verdeutlichung des Leistungsfaktors des Strahlers als Funktion der Frequenz.
In the drawing shows
Fig. 1
in schematic form a UV high-performance lamp with power supply device;
Fig. 2
a graphical representation to illustrate the voltage increase at the radiator as a function of frequency;
Fig. 3
a graphic representation to illustrate the power factor of the radiator as a function of frequency.

DETAILLIERTE BESCHREIBUNG DER ERFINDUNGDETAILED DESCRIPTION OF THE INVENTION

In Fig.1 ist ein UV-Hochleistungsstrahler generell mit der Bezugszahl 1, die zugehörige Stromversorgungseinrichtung mit 2 bezeichnet. Diese Stromversorgungseinrichtung, im folgenden allgemein mit "Umrichter" bezeichnet, besteht entweder aus einem sogenannten Schaltnetzgerät oder einem Frequenzgenerator mit nachgeschaltetem Leistungsverstärker Wesentlich dabei ist, dass dieser Umrichter bei Speisung mit technischem Wechselstrom einen Ausgangsstrom mit höherer Frequenz - typisch im Bereich kHz bis etwa 1 Mhz zu liefern imstande ist, wobei die Ausgangsspannung und/oder die Frequenz des Ausgangsstroms einstellbar sein sollte. Der Strahler 1 besteht im wesentlichen aus einem abgeschlossenen Entladungsraum 3, der mit einem Gas oder Gasgemisch gefüllt ist, das unter Enladungsbedingungen UV-Strahlung aussendet. Beispiele derartige Füllgase sind in dem eingangs genannten Patentdokument aufgelistet. Der Entladungsraum 3 ist auf beiden Seiten begrenzt von UV-durchlässigen Dielektrika 4 und 5, z.B. aus Quarzglas, auf welche äussere, UV-transparente Elektroden 6 und 7 aufgebracht sind. Die Elektrode 7 ist direkt, die Elektrode 6 ist über eine Induktivität 8 sind an die beiden Anschlüsse dee Umrichters 2 angeschlossen. Eine Zusatzkapazität 9 ist parallel zum Strahler 1 zuschaltbar. Schon aus der schematischen Darstellung des Strahlers 1 erhellt, dass der Strahler für den Umrichter eine Last mit hohem kapazitivem Anteil darstellt.In FIG. 1, a UV high-power radiator is generally designated by the reference number 1 and the associated power supply device by 2. This power supply device, hereinafter generally referred to as "converter", consists either of a so-called switched-mode power supply or a frequency generator with a power amplifier connected downstream. It is essential that this converter is supplied with technical alternating current is able to deliver an output current with a higher frequency - typically in the range kHz up to approximately 1 MHz, whereby the output voltage and / or the frequency of the output current should be adjustable. The radiator 1 essentially consists of a closed discharge space 3 which is filled with a gas or gas mixture which emits UV radiation under discharge conditions. Examples of such filling gases are listed in the patent document mentioned at the beginning. The discharge space 3 is delimited on both sides by UV-permeable dielectrics 4 and 5, for example made of quartz glass, to which outer, UV-transparent electrodes 6 and 7 are applied. The electrode 7 is direct, the electrode 6 is connected via an inductor 8 to the two connections of the converter 2. An additional capacitance 9 can be connected in parallel to the radiator 1. Already from the schematic representation of the radiator 1 it is clear that the radiator represents a load with a high capacitive component for the converter.

Die Diagramme gemäss Fig.2 und 3 verdeutlichen den Einfluss der Frequenz auf die Spannungsüberhöhung (Fig.2) bzw. den Leistungsfaktor (Fig.3) bei einem Strahler, der aus einem Frequenzgenerator mit nachgeschaltetem Leistungsverstärker mit einer Spannung von 130 Veff gespeist wurde und einen Entladungsspalt von 3 mm und Quarzdielektrika 4 und 5 von je 1,5 mm Dicke mit einer Dielektrizitätskonstanten von 3,7 aufwies. Die Kurvenzüge A geben dabei den theoretischen Verlauf, die Kurvenzüge B den gemessenen Verlauf wieder.The diagrams according to Fig. 2 and 3 illustrate the influence of the frequency on the voltage increase (Fig. 2) or the power factor (Fig. 3) for a radiator that was fed from a frequency generator with a downstream power amplifier with a voltage of 130 V eff and had a discharge gap of 3 mm and quartz dielectrics 4 and 5, each 1.5 mm thick, with a dielectric constant of 3.7. Curves A represent the theoretical course, curves B the measured course.

Um den Strahler ständig im gewünschten Leistungsfaktor-Bereich betreiben zu können, kann es notwendig sein, entweder die Frequenz der Umrichterausgangsspannung zu variieren, oder der Induktivität eine Zusatzinduktivität 8a parallel zu schalten oder beide Massnahmen gleichzeitig zu ergreifen.In order to be able to operate the radiator continuously in the desired power factor range, it may be necessary to either vary the frequency of the converter output voltage, to connect an additional inductor 8a to the inductor in parallel, or to take both measures simultaneously.

Claims (4)

Hochleistungsstrahler mit einem zumindest einseitig von einem Dielektrikum (4,5) begrenzten Entladungsraum (3), der mit einem Gas gefüllt ist, das unter Entladungsbedingungen Strahlung aussendet und einer Stromversorgungseinrichtung (2) zur Speisung der Entladung, dadurch gekennzeichnet, dass der Strahler (1) nur unter Zwischenschaltung einer Serieninduktivität (8) unmittelbar am Umrichterausgang angeschlossen ist und bei einem Leistungsfaktor nahe 1 betrieben wird, so dass an seinen Elektroden (6,7) eine Spannungsüberhöhung von mindestens 5 auftritt.High-power radiator with a discharge space (3) delimited at least on one side by a dielectric (4, 5), which is filled with a gas that emits radiation under discharge conditions, and a power supply device (2) for supplying the discharge, characterized in that the radiator (1 ) is only connected directly to the converter output with the interposition of a series inductor (8) and is operated at a power factor close to 1, so that a voltage increase of at least 5 occurs at its electrodes (6,7). Strahler nach Anspruch 1, dadurch gekennzeichnet, dass parallel zum Strahler (1) eine Zusatzkapazität (9) schaltbar ist.Radiator according to claim 1, characterized in that an additional capacitance (9) can be switched parallel to the radiator (1). Strahler nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass der Umrichter Mittel zur Veränderung der Frequenz seiner Ausgangsspannung vorgesehen sind.Radiator according to claim 1 or 2, characterized in that the converter means are provided for changing the frequency of its output voltage. Strahler nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass parallel zur Induktivität (8) eine Zusatzinduktivität (8a) schaltbar ist.Radiator according to one of claims 1 to 3, characterized in that an additional inductance (8a) can be switched parallel to the inductance (8).
EP91106024A 1990-04-24 1991-04-15 High power radiation device with power supply Withdrawn EP0459127A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CH1381/90 1990-04-24
CH1381/90A CH680246A5 (en) 1990-04-24 1990-04-24

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1932168A2 (en) * 2005-10-04 2008-06-18 Topanga Technologies External resonator/cavity electrode-less plasma lamp and method of exciting with radio-frequency energy

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10342337A1 (en) * 2003-09-11 2005-05-04 Heraeus Noblelight Gmbh Discharge lamp for disinfecting purposes, for cleaning surfaces, for psoriasis treatment or polymer hardening comprises a discharge vessel formed by a tube which is connected at both ends

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB515077A (en) * 1938-06-07 1939-11-24 Richard Huddelson Seaman Supply system for electric discharge lamps
US2832009A (en) * 1955-01-11 1958-04-22 Triflux Soc Glow discharge systems
FR1337408A (en) * 1962-07-31 1963-09-13 Ile Soc Civ Frequency stabilizer system
US4358712A (en) * 1980-12-29 1982-11-09 Altex Scientific, Inc. Discharge lamp ballast
GB2163014A (en) * 1984-08-06 1986-02-12 Gen Electric Ballast circuits for fluorescent lamps
GB2204751A (en) * 1987-04-22 1988-11-16 Davis Group Ltd Discharge lamp circuits
EP0336642A1 (en) * 1988-04-05 1989-10-11 Neon Dynamics Corporation Excitation supply for gas discharge tubes
US4914558A (en) * 1989-03-06 1990-04-03 Jon Flickinger Series resonant inverter and method of lamp starting
EP0254111B1 (en) * 1986-07-22 1992-01-02 BBC Brown Boveri AG Ultraviolett radiation device

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB515077A (en) * 1938-06-07 1939-11-24 Richard Huddelson Seaman Supply system for electric discharge lamps
US2832009A (en) * 1955-01-11 1958-04-22 Triflux Soc Glow discharge systems
FR1337408A (en) * 1962-07-31 1963-09-13 Ile Soc Civ Frequency stabilizer system
US4358712A (en) * 1980-12-29 1982-11-09 Altex Scientific, Inc. Discharge lamp ballast
GB2163014A (en) * 1984-08-06 1986-02-12 Gen Electric Ballast circuits for fluorescent lamps
EP0254111B1 (en) * 1986-07-22 1992-01-02 BBC Brown Boveri AG Ultraviolett radiation device
GB2204751A (en) * 1987-04-22 1988-11-16 Davis Group Ltd Discharge lamp circuits
EP0336642A1 (en) * 1988-04-05 1989-10-11 Neon Dynamics Corporation Excitation supply for gas discharge tubes
US4914558A (en) * 1989-03-06 1990-04-03 Jon Flickinger Series resonant inverter and method of lamp starting

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1932168A2 (en) * 2005-10-04 2008-06-18 Topanga Technologies External resonator/cavity electrode-less plasma lamp and method of exciting with radio-frequency energy

Also Published As

Publication number Publication date
JPH04230951A (en) 1992-08-19
CH680246A5 (en) 1992-07-15

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