EP0340049A1 - Supplying device for a luminescent tube - Google Patents

Supplying device for a luminescent tube Download PDF

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Publication number
EP0340049A1
EP0340049A1 EP89400338A EP89400338A EP0340049A1 EP 0340049 A1 EP0340049 A1 EP 0340049A1 EP 89400338 A EP89400338 A EP 89400338A EP 89400338 A EP89400338 A EP 89400338A EP 0340049 A1 EP0340049 A1 EP 0340049A1
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EP
European Patent Office
Prior art keywords
transformer
winding
primary winding
oscillator
voltage
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.)
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Application number
EP89400338A
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German (de)
French (fr)
Inventor
Roger Schneider
Alain Perchat
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APPLICATIONS ET UTILISATIONS DES PROPRIETES ELECTRIQUES DES MATERIAUX
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APPLICATIONS ET UTILISATIONS DES PROPRIETES ELECTRIQUES DES MATERIAUX
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Publication of EP0340049A1 publication Critical patent/EP0340049A1/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
    • H05B41/26—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc
    • H05B41/28—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters
    • H05B41/282—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters with semiconductor devices
    • H05B41/2825—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters with semiconductor devices by means of a bridge converter in the final stage
    • H05B41/2827—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters with semiconductor devices by means of a bridge converter in the final stage using specially adapted components in the load circuit, e.g. feed-back transformers, piezoelectric transformers; using specially adapted load circuit configurations
    • 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
    • H05B41/26—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc
    • H05B41/28—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters
    • H05B41/282—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters with semiconductor devices
    • H05B41/285—Arrangements for protecting lamps or circuits against abnormal operating conditions
    • H05B41/2851—Arrangements for protecting lamps or circuits against abnormal operating conditions for protecting the circuit against abnormal operating conditions
    • H05B41/2855—Arrangements for protecting lamps or circuits against abnormal operating conditions for protecting the circuit against abnormal operating conditions against abnormal lamp operating conditions
    • 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
    • H05B41/26—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc
    • H05B41/28—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters
    • H05B41/282—Circuit arrangements in which the lamp is fed by power derived from dc by means of a converter, e.g. by high-voltage dc using static converters with semiconductor devices
    • H05B41/285—Arrangements for protecting lamps or circuits against abnormal operating conditions
    • H05B41/2858—Arrangements for protecting lamps or circuits against abnormal operating conditions for protecting the lamp against abnormal operating conditions
    • 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
    • H05B41/36—Controlling
    • H05B41/38—Controlling the intensity of light
    • H05B41/39—Controlling the intensity of light continuously
    • H05B41/392—Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor
    • 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
    • H05B41/36—Controlling
    • H05B41/38—Controlling the intensity of light
    • H05B41/39—Controlling the intensity of light continuously
    • H05B41/392—Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor
    • H05B41/3921—Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor with possibility of light intensity variations
    • H05B41/3925—Controlling the intensity of light continuously using semiconductor devices, e.g. thyristor with possibility of light intensity variations by frequency variation

Definitions

  • the invention relates to a luminescent tube supply device provided with a semiconductor switching oscillator; it relates more particularly to a set of improvements making it possible to improve the reliability of this type of device, while making it possible to use only one model of apparatus, for luminescent tubes of different lengths.
  • the invention proposes a new type of electronic device for feeding a luminescent tube, having increased reliability, a saving in weight and size and better current regulation.
  • the proposed device is also remarkable in that it automatically adapts to any type of luminescent tube, especially of any length.
  • the invention therefore relates to a luminescent tube supply device, characterized in that it comprises: - a variable frequency switching oscillator comprising a first transformer provided with a primary winding and a saturation winding, a second transformer comprising a primary winding, one end of which is connected to said primary winding of said first transformer, a secondary winding intended to be connected to said luminescent tube and a reference winding, and - regulating means arranged between said reference winding and said saturation winding to regulate the current passing through said luminescent tube by varying the operating frequency of said oscillator.
  • a variable frequency switching oscillator comprising a first transformer provided with a primary winding and a saturation winding
  • a second transformer comprising a primary winding, one end of which is connected to said primary winding of said first transformer, a secondary winding intended to be connected to said luminescent tube and a reference winding
  • - regulating means arranged between said reference winding and said saturation winding to regulate the current passing through said luminescent tube by
  • the windings of said second transformer are highly coupled (as opposed to the leakage transformer generally used) and the primary winding of this transformer is connected to the primary winding of said first transformer by means of a self-induction separate.
  • This arrangement allows effective protection of the transformer, particularly in the case of no-load operation, thanks to the addition of a simple diode protection circuit.
  • Another object of the invention is to prevent the occurrence of such a phenomenon.
  • the invention also relates to a device of the kind defined above and further comprising a means for establishing different amplitude values between two consecutive half-waves of said switching oscillator.
  • this means can consist of a Zener diode interposed between said saturation winding and said regulation means. Indeed, it has been found that the fact of creating an imbalance between the half-waves of the switching oscillator had the result of making said resonance phenomenon "in balls" disappear.
  • the supply device as shown diagrammatically in FIG. 1 mainly consists of a switching oscillator 11 with variable frequency, a first transformer 12 forming part of this oscillator, a second transformer 13 capable of supplying a luminescent tube 14 , a self-induction 15 and regulation means 16 arranged between the transformers 12 and 13.
  • Electric power is supplied here by the alternative layout network connected to the V AC terminals.
  • This voltage for example of 220 Volts is rectified by a conventional bridge rectifier 18, developing between the conductors 19 and 20 a rectified voltage whose waveform is substantially that of a succession of half-sinusoids.
  • the capacitors C1 and C2 connected in series between the conductors 19 and 20 have, here, a relatively low capacity, so that the rectified voltage does not undergo proper "filtering".
  • supply voltage source V R
  • any direct voltage possibly rectified and not filtered (that is to say of the shape of one indicated above) capable of supplying the oscillator 11. This voltage is therefore applied between the conductors 19 and 20.
  • the device could also operate from a stable continuous voltage, i.e. a filtered rectified voltage or a voltage supplied by an accumulator battery.
  • the switching oscillator 11 comprises, in addition to the transformer 12, two oscillating half-bridges.
  • the first half-bridge is made up of semiconductor components, here transistors Q1, Q2 and more particularly field effect transistors, of the MOS type.
  • the second half-bridge is formed by the two capacitors C1, C2 mentioned above.
  • the transistors Q1 and Q2 are mounted with their drain-source circuits in series, between the conductors 19 and 20.
  • Each of the control inputs of the transistors Q1, Q2 (here their "gates") are connected to secondary windings 12 b , 12 c , respective of the transformer 12.
  • the primary winding 12 a of this same transformer is connected by one of its ends to the midpoint of the half-bridge of transistors, that is to say ie between the two transistors Q1, Q2.
  • the primary winding 13 a of the second transformer 13 is connected between the two half-bridges via the series connection of the primary winding 12 a (which has only a few turns) and of the self-induction 15. More precisely, a first end of primary winding 13 a is connected to primary winding 12 a via self-induction 15 while a second end of primary winding 13 a is connected to the midpoint of the half bridge of capacitors C1, C2.
  • a starting network of the oscillator 11 comprises a resistor R1, a diode D1, a diac 25 and a capacitor C3.
  • the resistor R1 connected to the conductor 19 forms a series branch with the capacitor C3 connected to the conductor 20.
  • the diode D1 is connected between the midpoint of this branch and the midpoint of the half-bridge of transistors.
  • the diac 25 is connected between the "gate" of the transistor Q2 and the midpoint of said series branch R1, C3.
  • the resistor R1 charges the capacitor C3 until the voltage across the latter is equal to the starting voltage of the diac 25, which transmits the energy, accumulated in the capacitor C3, to the "grid "of the transistor Q2, which triggers the first conduction of the transistor and the self-oscillation of the switching oscillator 11.
  • the diode D1 short-circuits the capacitor C3 at each conduction of the transistor Q2, to avoid untimely starting of the diac 25.
  • the second transformer 13 is not a "leaky” transformer.
  • the coupling between its windings, in particular the primary winding 13 a and the secondary winding 13 b is high.
  • the luminescent tube 14 is designed to be directly connected to the terminals of this secondary winding 13b .
  • the combination of the transformer 13 and the self-induction 15 advantageously replaces a "leaky” transformer, as will be seen below. Therefore, the switching oscillator 11 can be completed by a diode half-bridge D2, D3 in series, connected in reverse to the rectified voltage source, that is to say between the conductors 19 and 20.
  • the midpoint of this half-diode bridge is connected to the link established between the self-induction 15 and said first end of the primary winding 13 a of the second transformer 13. The role of this half-diode bridge will be explained more far.
  • said first transformer 12 comprises a saturation winding 12 d
  • said second transformer 13 comprises a reference winding 13 c
  • the regulating means 16 are arranged between said reference winding 13 c and said winding saturation 12 d , so as to regulate the current passing through the luminescent tube 14, by varying the operating frequency of the switching oscillator 11.
  • these means of regulation comprise first rectifying means constituted here by a simple diode D4 connected to the reference winding 13 c and ensuring a full-wave rectification, as well as second rectifying means 26, constituted here by a bridge of four diodes ensuring rectification double alternation.
  • This diode bridge is connected to the terminals of the saturation winding 12 d and a charging circuit 30 is established between the terminals of rectified voltage of said rectifying means 26.
  • This charging circuit 30 comprises in particular a semiconductor component such that 'a transistor Q3 developing between its terminals a voltage representative of the DC voltage produced by said first rectifying means.
  • this semiconductor component is a field effect transistor and the drain-source link of this transistor is part of said load circuit.
  • Said first rectification means that is to say the diode D4, is connected to charge a capacitor C4 at the terminals of which a potentiometer P1 is connected, the cursor of which is connected to the control electrode (here the "grid") of transistor Q3. Consequently, part of the voltage developed across the capacitor C4 is taken by the potentiometer P1 to drive the transistor Q3.
  • the drain-source link of the latter is connected in series with a Zener diode Z1 which is also part of said load circuit 30. Consequently, at each half-wave of oscillator 11, the voltage "seen” by the saturation winding 12 d depends on the voltage developed across the charge circuit defined above.
  • Zener diode Z2 is connected in parallel on the drain-source link of the transistor Q3 as well as a low value capacitor C5, whose role is to eliminate the parasites.
  • the role of the Zener diode Z1 is to limit the frequency of the oscillator 11 when the device is operating at no load, that is to say when the transistor Q3 is saturated.
  • the Zener diode Z2 determines an upper limit of saturation voltage for the winding 12 d in the case where the transistor Q3 is blocked, which can, for example, be caused by an operation in short-circuit.
  • the device described comprises means for establishing values of different amplitudes between two consecutive half-waves of said switching oscillator 11, that is to say to create a difference between the half-waves corresponding respectively to the conductions of the transistors Q1 and Q2.
  • it is a simple Zener diode Z3 interposed between the saturation winding 12 d and the second rectification means 26. In this way, the voltage "seen" by the saturation winding 12 d is different from one alternation to another depending on the direction of current flow in the Zener diode Z3.
  • the operation of the device which has just been described is as follows: As soon as the device is connected to the AC distribution network V AC , the chopping oscillator 11 enters into self-oscillation, the transistors Q1 and Q2 being periodically switched under the control of the windings 12 b and 12 c . Taking into account the assembly, the current passing through the primary winding 12 a , also passes through the primary winding 13 a and the self-induction 15. In accordance with the principle of the invention, the frequency of the oscillator 11 will stabilize around d a value for which the luminescent tube 14 will be traversed by a suitably chosen current, with regulation of the latter.
  • the luminescent tube 14 behaves practically like a Zener diode "imposing" the voltage across its terminals, that is to say across the terminals of the secondary winding 13b .
  • This voltage depends on the specific characteristics of the luminescent tube 14 and in particular its length. It is therefore important to regulate the current passing through the tube 14 so that the latter operates under optimal conditions. In fact, if the current is too weak, the lighting is poor and if it is too strong, the life of the tube is shortened.
  • the regulation means 16 regulate the current sought. Indeed, the self-induction 15 limits the variation of current in the primary winding 13 a of the transformer 13. Now, the voltage across the terminals of the primary winding 13 a imposed by the tube 14 and all of the voltage d available power is shared between the primary winding 13 a and the self-induction 15. Consequently, if the voltage tends to increase at the terminals of the primary winding 13 a , then the voltage at the terminals of the self-induction 15 tends to decrease. The growth of the current at each half-wave therefore also tends to decrease. If one wants to maintain the peak current in the tube 14 at a constant value, it is therefore necessary to drive longer at each half-wave, that is to say that the frequency of the oscillator 11 must decrease.
  • the diodes D2 and D3 make it possible to avoid overvoltages during a no-load operation (that is to say for example when the tube 14 is broken) by returning the energy accumulated in the transformer 13 to one of the capacitors C1 or C2.
  • the energy accumulated when it blocks has tendency to generate an overvoltage between the primary winding 13 a and the self-inductance 15.
  • this overvoltage is eliminated by the fact that the energy is returned to the capacitor C1 by the diode D2. Under these conditions, the voltage excursion across the terminals of the primary winding is limited to that of the AC distribution network and the transformer 13 is of course calculated to withstand such a voltage.
  • this series connection of the primary winding 13 a of a high coupling transformer 13 with a self-inductance 15 is the equivalent of a "leaky” transformer, the self-inductance 15 materializing in a way the "escape self".
  • a transformer "without leakage” and a separate inductance it is possible to connect the half-bridge of diodes D2, D3, that is to say the elimination of overvoltages in no-load operation.
  • the fact of separating the transformer 13 from the “leakage choke” 15 makes it possible to properly control the transformation ratio of the transformer 13.
  • a secondary 13 b known as “with taps” comprising selected numbers of turns between a common terminal a and terminals b , c , d , for supplying different luminescent tubes requiring different currents.
  • the luminescent tubes are classified into three main families according to the admissible current (25mA, 50mA, 100mA) it is possible, from a single transformer 13 and therefore from a single model of device power supply, to cover the whole range of luminescent tubes.
  • FIG. 2 illustrates a variant in which the transistor Q3 is replaced by an adjustable Zener diode Z4.
  • the control input of this diode is connected to the cursor of the potentiometer P1 while a resistor R1 establishes a feedback between the common point of the diodes Z1 and Z2 and the said control input of the diode Z4.
  • the latter is equivalent to an operational amplifier with integrated reference.

Abstract

Supply device for a luminescent tube comprising a chopping oscillator and means of regulating the current in the said tube. According to the invention, the primary winding (13a) of the transformer (13) supplying the luminescent tube (14) is supplied via a chopping oscillator (11) and regulating means (16) are inserted between a reference winding (13c) of the transformer (13) and a saturation winding (12d) of the transformer (12) of the oscillator (11) in such a way as to regulate the current in the luminescent tube (14) by varying the frequency of oscillation of the chopping oscillator (11). The same device may be suitable for luminescent tubes of differing lengths. <IMAGE>

Description

L'invention se rapporte à un dispositif d'alimentation de tube luminescent muni d'un oscillateur à découpage, à semi-conducteurs; elle concerne plus particulièrement un ensemble de perfectionnements permettant d'améliorer la fiabilité de ce type de dispositif, tout en permettant de n'utiliser qu'un seul modèle d'appareil, pour des tubes luminescents de longueurs différentes.The invention relates to a luminescent tube supply device provided with a semiconductor switching oscillator; it relates more particularly to a set of improvements making it possible to improve the reliability of this type of device, while making it possible to use only one model of apparatus, for luminescent tubes of different lengths.

La plupart des dispositifs d'alimentation de tubes luminescents comportent des transformateurs d'alimentation "à fuite" fonctionnant à la fréquence du réseau alternatif de distribution, c'est-à-dire 50 ou 60Hz. De tels dispositifs sont lourds, volumineux et encombrants. Comme il n'y a aucune possibilité de réguler le courant dans le tube luminescent, les constructeurs doivent prévoir un type de transformateur pour chaque modèle de tube. Ceci augmente les coûts de fabrication et de stockage. De plus, si le dispositif fonctionne à vide (ce qui peut se produire notamment si le tube luminescent est cassé) la tension élevée développée par l'enroulement secondaire du transformateur peut provoquer un claquage entre spires et donc une destruction dudit transformateur. Plus récemment, on a proposé des dispositifs électroniques fonctionnant à une fréquence relativement élevée (de l'ordre de 20 kHz) permettant une certaine régulation de courant mais faisant toujours appel à un transformateur "à fuite" à la sortie, avec les inconvénients mentionnés ci-dessus. Ce type de dispositif n'a pas atteint jusqu'à présent, une fiabilité suffisante, tant du point de vue de la régulation que des risques de claquage en fonctionnement à vide.Most devices for supplying luminescent tubes include "leakage" power transformers operating at the frequency of the alternative distribution network, that is to say 50 or 60 Hz. Such devices are heavy, bulky and bulky. As there is no possibility of regulating the current in the luminescent tube, the manufacturers must envisage a type of transformer for each model of tube. This increases manufacturing and storage costs. In addition, if the device operates empty (which can happen in particular if the luminescent tube is broken) the high voltage developed by the secondary winding of the transformer can cause breakdown between turns and therefore destruction of said transformer. More recently, electronic devices have been proposed operating at a relatively high frequency (of the order of 20 kHz) allowing some current regulation but always using a "leaky" transformer at the output, with the drawbacks mentioned above. -above. This type of device has so far not achieved sufficient reliability, both from the point of view of regulation and the risks of breakdown in idle operation.

L'invention propose un nouveau type de dispositif électronique pour l'alimentation d'un tube luminescent, présentant une fiabilité accrue, un gain de poids et d'encombrement et une meilleure régulation de courant. Le dispositif proposé est également remarquable en ce qu'il s'adapte automatiquement à tout type de tube luminescent, notamment de n'importe quelle longueur.The invention proposes a new type of electronic device for feeding a luminescent tube, having increased reliability, a saving in weight and size and better current regulation. The proposed device is also remarkable in that it automatically adapts to any type of luminescent tube, especially of any length.

Dans cet esprit, l'invention concerne donc un dispositif d'alimentation de tube luminescent, caractérisé en ce qu'il comprend:
- un oscillateur à découpage à fréquence variable comportant un premier transformateur muni d'un enroulement primaire et d'un enroulement de saturation,
- un second transformateur comportant un enroulement primaire dont une extrémité est reliée audit enroulement primaire dudit premier transformateur, un enroulement secondaire prévu pour être connecté audit tube luminescent et un enroulement de référence, et
- des moyens de régulation agencés entre ledit enroulement de référence et ledit enroulement de saturation pour réguler le courant traversant ledit tube luminescent en faisant varier la fréquence de fonctionnement dudit oscillateur.In this spirit, the invention therefore relates to a luminescent tube supply device, characterized in that it comprises:
- a variable frequency switching oscillator comprising a first transformer provided with a primary winding and a saturation winding,
a second transformer comprising a primary winding, one end of which is connected to said primary winding of said first transformer, a secondary winding intended to be connected to said luminescent tube and a reference winding, and
- regulating means arranged between said reference winding and said saturation winding to regulate the current passing through said luminescent tube by varying the operating frequency of said oscillator.

De préférence, les enroulements dudit second transformateur sont à couplage élevé (par opposition au transformateur à fuite généralement utilisé) et l'enroulement primaire de ce transformateur est relié à l'enroulement primaire dudit premier transformateur par l'intermédiaire d'une self-induction séparée. Ce montage permet une protection efficace du transformateur, notamment en cas de fonctionnement à vide, grâce à l'adjonction d'un simple circuit de protection à diodes.Preferably, the windings of said second transformer are highly coupled (as opposed to the leakage transformer generally used) and the primary winding of this transformer is connected to the primary winding of said first transformer by means of a self-induction separate. This arrangement allows effective protection of the transformer, particularly in the case of no-load operation, thanks to the addition of a simple diode protection circuit.

De plus, dans le système d'alimentation haute fréquence connu, on observe souvent un phémonène de résonance dite "en billes", le long du tube, c'est-à-dire une variation d'intensité lumineuse le long du tube, avec apparition de ventres et de noeuds de luminosité. Un autre but de l'invention est de prévenir l'apparition d'un tel phénomène.In addition, in the known high-frequency power system, a so-called "ball" resonance phemonene is often observed along the tube, that is to say a variation in light intensity along the tube, with appearance of bellies and nodes of luminosity. Another object of the invention is to prevent the occurrence of such a phenomenon.

Dans ce but, l'invention concerne également un dispositif du genre défini ci-dessus et comportant en outre un moyen pour établir des valeurs d'amplitude différentes entre deux alternances consécutives dudit oscillateur à découpage.For this purpose, the invention also relates to a device of the kind defined above and further comprising a means for establishing different amplitude values between two consecutive half-waves of said switching oscillator.

Selon un mode de réalisation particulièrement simple, ce moyen peut consister en une diode Zener intercalée entre ledit enroulement de saturation et lesdits moyens de régulation. En effet, on a constaté que le fait de créer un déséquilibre entre les alternances de l'oscillateur à découpage avait pour résultat de faire disparaître ledit phénomène de résonance "en billes".According to a particularly simple embodiment, this means can consist of a Zener diode interposed between said saturation winding and said regulation means. Indeed, it has been found that the fact of creating an imbalance between the half-waves of the switching oscillator had the result of making said resonance phenomenon "in balls" disappear.

L'invention sera mieux comprise et d'autres avantages de celle-ci apparaîtront plus clairement à la lumière de la description que va suivre d'un mode de réalisation d'un dispositif conforme à son principe donnée uniquement à titre d'exemple et faite en référence aux dessins dans lesquels:

  • - la figure 1 est un schéma de principe d'un tel dispositif d'alimentation de tube luminescent; et
  • - la figure 2 est une variante de l'encadré II de la figure 1.
The invention will be better understood and other advantages thereof will appear more clearly in the light of the description which will follow of an embodiment of a device in accordance with its principle given solely by way of example and made with reference to the drawings in which:
  • - Figure 1 is a block diagram of such a luminescent tube supply device; and
  • - Figure 2 is a variant of Box II of Figure 1.

Le dipositif d'alimentation tel que schématisé figure 1 se compose principalement d'un oscillateur à découpage 11 à fréquence variable, d'un premier transformateur 12 faisant partie de cet oscillateur, d'un second transformateur 13 susceptible d'alimenter un tube luminescent 14, d'une self-induction 15 et de moyens de régulation 16 agencés entre les transformateurs 12 et 13.The supply device as shown diagrammatically in FIG. 1 mainly consists of a switching oscillator 11 with variable frequency, a first transformer 12 forming part of this oscillator, a second transformer 13 capable of supplying a luminescent tube 14 , a self-induction 15 and regulation means 16 arranged between the transformers 12 and 13.

L'énergie électrique est fournie ici par le réseau alternatif de disposition connecté aux bornes VAC. Cette tension, par exemple de 220 Volts est redressée par une redresseur en pont 18 classique, développant entre les conducteurs 19 et 20 une tension redressée dont la forme d'onde est sensiblement celle d'une succession de demi-sinusoïdes. Il est à noter en effet que les condensateurs C1 et C2 connectés en série entre les conducteurs 19 et 20 ont, ici, une capacité relativement faible, de sorte que la tension redressée ne subit pas de "filtrage" à proprement parler. On appellera dans la suite du texte "source de tension d'alimentation" VR, toute tension continue, éventuellement redressée et non filtrée (c'est-à-dire de la forme d'one indiquée ci-dessus) susceptible d'alimenter l'oscillateur 11. Cette tension est donc appliquée entre les conducteurs 19 et 20. Le dispositif pourrait aussi fonctionner à partir d'une tension continue stable, c'est-à-dire une tension redressée filtrée ou bien une tension délivrée par une batterie d'accumulateurs.Electric power is supplied here by the alternative layout network connected to the V AC terminals. This voltage, for example of 220 Volts is rectified by a conventional bridge rectifier 18, developing between the conductors 19 and 20 a rectified voltage whose waveform is substantially that of a succession of half-sinusoids. It should be noted in fact that the capacitors C1 and C2 connected in series between the conductors 19 and 20 have, here, a relatively low capacity, so that the rectified voltage does not undergo proper "filtering". In the following text, we will call "supply voltage source" V R , any direct voltage, possibly rectified and not filtered (that is to say of the shape of one indicated above) capable of supplying the oscillator 11. This voltage is therefore applied between the conductors 19 and 20. The device could also operate from a stable continuous voltage, i.e. a filtered rectified voltage or a voltage supplied by an accumulator battery.

L'oscillateur à découpage 11 comprend, outre le transformateur 12, deux demi-ponts oscillants. Le premier demi-pont est constitué par des composants semi-conducteurs, ici des transistors Q1, Q2 et plus particulièrement des transistors à effet de champ, de type MOS. Le second demi-pont est constitué par les deux condensateurs C1, C2 mentionnés ci-dessus. Dans le demi-pont de semi-conducteurs, les transistors Q1 et Q2 sont montés avec leurs circuits drain-source en série, entre les conducteurs 19 et 20. Chacune des entrées de commande des transistors Q1, Q2 (ici leurs "grilles") sont reliées à des enroulements secondaires 12b, 12c, respectifs du transformateur 12. L'enroulement primaire 12a de ce même transformateur est relié par l'une de ses extrémités au point milieu du demi-pont de transistors, c'est-à-dire entre les deux transistors Q1, Q2. L'enroulement primaire 13a du second transformateur 13 est connecté entre les deux demi-ponts via le montage en série de l'enroulement primaire 12a (qui ne comporte que quelques spires) et de la self-induction 15. Plus précisément, une première extrémité de l'enroulement primaire 13a est reliée à l'enroulement primaire 12a par l'intermédiaire de la self-induction 15 tandis qu'une deuxième extrémité de l'enroulement primaire 13a est reliée au point milieu du demi-pont de condensateurs C1, C2. Un réseau de démarrage de l'oscillateur 11 comprend une résistance R1, une diode D1, un diac 25 et un condensateur C3. La résistance R1, connectée au conducteur 19 forme une branche série avec le condensateur C3 connecté au conducteur 20. La diode D1 est connectée entre le point milieu de cette branche et le point milieu du demi-pont de transistors. Le diac 25 est connecté entre la "grille" du transistor Q2 et le point milieu de ladite branche série R1, C3.The switching oscillator 11 comprises, in addition to the transformer 12, two oscillating half-bridges. The first half-bridge is made up of semiconductor components, here transistors Q1, Q2 and more particularly field effect transistors, of the MOS type. The second half-bridge is formed by the two capacitors C1, C2 mentioned above. In the semiconductor half-bridge, the transistors Q1 and Q2 are mounted with their drain-source circuits in series, between the conductors 19 and 20. Each of the control inputs of the transistors Q1, Q2 (here their "gates") are connected to secondary windings 12 b , 12 c , respective of the transformer 12. The primary winding 12 a of this same transformer is connected by one of its ends to the midpoint of the half-bridge of transistors, that is to say ie between the two transistors Q1, Q2. The primary winding 13 a of the second transformer 13 is connected between the two half-bridges via the series connection of the primary winding 12 a (which has only a few turns) and of the self-induction 15. More precisely, a first end of primary winding 13 a is connected to primary winding 12 a via self-induction 15 while a second end of primary winding 13 a is connected to the midpoint of the half bridge of capacitors C1, C2. A starting network of the oscillator 11 comprises a resistor R1, a diode D1, a diac 25 and a capacitor C3. The resistor R1, connected to the conductor 19 forms a series branch with the capacitor C3 connected to the conductor 20. The diode D1 is connected between the midpoint of this branch and the midpoint of the half-bridge of transistors. The diac 25 is connected between the "gate" of the transistor Q2 and the midpoint of said series branch R1, C3.

Au démarrage, la résistance R1 charge le condensateur C3 jusqu'à ce que la tension aux bornes de ce dernier soit égale à la tension d'amorçage du diac 25, qui transmet l'énergie, accumulée dans le condensateur C3, à la "grille" du transistor Q2, ce qui déclenche la première conduction du transistor et la mise en auto-oscillation de l'oscillateur à découpage 11. En fonctionnement, la diode D1 court-circuite le condensateur C3 à chaque conduction du transistor Q2, pour éviter des amorçages intempestifs du diac 25.At start-up, the resistor R1 charges the capacitor C3 until the voltage across the latter is equal to the starting voltage of the diac 25, which transmits the energy, accumulated in the capacitor C3, to the "grid "of the transistor Q2, which triggers the first conduction of the transistor and the self-oscillation of the switching oscillator 11. In operation, the diode D1 short-circuits the capacitor C3 at each conduction of the transistor Q2, to avoid untimely starting of the diac 25.

Selon une caractéristique avantageuse de l'invention, le second transformateur 13 n'est pas un transformateur "à fuite". Autrement dit, le couplage entre ses enroulements, notamment l'enroulement primaire 13a et l'enroulement secondaire 13b est élevé. Le tube luminescent 14 est prévu pour être directement connecté aux bornes de cet enroulement secondaire 13b. En fait, l'association du transformateur 13 et de la self-induction 15 remplace avantageusement un transformateur "à fuite", comme on le verra plus loin. De ce fait, l'oscillateur à découpage 11 peut être complété par un demi-pont de diodes D2, D3 en série, connecté en inverse à la source de tension redressée, c'est-à-dire entre les conducteurs 19 et 20. Le point milieu de ce demi-pont de diodes est connecté à la liaison établie entre la self-induction 15 et ladite première extrémité de l'enroulement primaire 13a du second transformateur 13. Le rôle de ce demi-pont de diodes sera expliqué plus loin.According to an advantageous characteristic of the invention, the second transformer 13 is not a "leaky" transformer. In other words, the coupling between its windings, in particular the primary winding 13 a and the secondary winding 13 b is high. The luminescent tube 14 is designed to be directly connected to the terminals of this secondary winding 13b . In fact, the combination of the transformer 13 and the self-induction 15 advantageously replaces a "leaky" transformer, as will be seen below. Therefore, the switching oscillator 11 can be completed by a diode half-bridge D2, D3 in series, connected in reverse to the rectified voltage source, that is to say between the conductors 19 and 20. The midpoint of this half-diode bridge is connected to the link established between the self-induction 15 and said first end of the primary winding 13 a of the second transformer 13. The role of this half-diode bridge will be explained more far.

Selon une caractéristique importante de l'invention, ledit premier transformateur 12 comporte un enroulement de saturation 12d, ledit second transformateur 13 comporte un enroulement de référence 13c et les moyens de régulation 16 sont agencés entre ledit enroulement de référence 13c et ledit enroulement de saturation 12d, de façon à réguler le courant traversant le tube luminescent 14, en faisant varier la fréquence de fonctionnement de l'oscillateur à découpage 11.According to an important characteristic of the invention, said first transformer 12 comprises a saturation winding 12 d , said second transformer 13 comprises a reference winding 13 c and the regulating means 16 are arranged between said reference winding 13 c and said winding saturation 12 d , so as to regulate the current passing through the luminescent tube 14, by varying the operating frequency of the switching oscillator 11.

Dans l'exemple décrit, ces moyens de régulation comportent des premiers moyens de redressement constitués ici par une simple diode D4 connectée à l'enroulement de référence 13c et assurant un redressement mono-alternance, ainsi que des seconds moyens de redressement 26, constitués ici par une pont de quatre diodes assurant un redressement double-alternance. Ce pont de diodes est relié aux bornes de l'enroulement de saturation 12d et un circuit de charge 30 est établi entre les bornes de tension redressée dudit moyen de redressement 26. Ce circuit de charge 30 comporte notamment un composant semi-conducteur tel qu'un transistor Q3 développant entre ses bornes une tension représentative de la tension continue élaborée par ledit premier moyen de redressement. Dans l'exemple, ce composant semi-conducteur est un transistor à effet de champ et la liaison drain-source de ce transistor fait partie dudit circuit de charge. C'est donc entre la source et le drain de ce transistor que se développe ladite tension représentative. Ledit premier moyen de redressement, c'est-à-dire la diode D4, est connecté pour charger une condensateur C4 aux bornes duquel est branché un potentiomètre P1 dont le curseur est relié à l'électrode de commande (ici la "grille") du transistor Q3. Par conséquent, une partie de la tension développée aux bornes du condensateur C4 est prélevée par le potentiomètre P1 pour piloter le transistor Q3. De plus, la liaison drain-source de ce dernier est montée en série avec une diode Zener Z1 qui fait également partie dudit circuit de charge 30. Par conséquent, à chaque alternance de l'oscillateur 11, la tension "vue" par l'enroulement de saturation 12d dépend de la tension développée aux bornes du circuit de charge défini ci-dessus. Une autre diode Zener Z2 est connectée en parallèle sur la liaison drain-source du transistor Q3 ainsi qu'un condensateur C5 de faible valeur, dont le rôle est d'éliminer les parasites. Le rôle de la diode Zener Z1 est de limiter la fréquence de l'oscillateur 11 lorsque le dispositif fonctionne à vide, c'est-à-dire lorsque le transistor Q3 est saturé. La diode Zener Z2 détermine une limite haute de tension de saturation pour l'enroulement 12d dans le cas où le transistor Q3 se trouve bloqué, ce qui peut, par exemple, être provoqué par un fonctionnement en court-circuit.In the example described, these means of regulation comprise first rectifying means constituted here by a simple diode D4 connected to the reference winding 13 c and ensuring a full-wave rectification, as well as second rectifying means 26, constituted here by a bridge of four diodes ensuring rectification double alternation. This diode bridge is connected to the terminals of the saturation winding 12 d and a charging circuit 30 is established between the terminals of rectified voltage of said rectifying means 26. This charging circuit 30 comprises in particular a semiconductor component such that 'a transistor Q3 developing between its terminals a voltage representative of the DC voltage produced by said first rectifying means. In the example, this semiconductor component is a field effect transistor and the drain-source link of this transistor is part of said load circuit. It is therefore between the source and the drain of this transistor that said representative voltage develops. Said first rectification means, that is to say the diode D4, is connected to charge a capacitor C4 at the terminals of which a potentiometer P1 is connected, the cursor of which is connected to the control electrode (here the "grid") of transistor Q3. Consequently, part of the voltage developed across the capacitor C4 is taken by the potentiometer P1 to drive the transistor Q3. In addition, the drain-source link of the latter is connected in series with a Zener diode Z1 which is also part of said load circuit 30. Consequently, at each half-wave of oscillator 11, the voltage "seen" by the saturation winding 12 d depends on the voltage developed across the charge circuit defined above. Another Zener diode Z2 is connected in parallel on the drain-source link of the transistor Q3 as well as a low value capacitor C5, whose role is to eliminate the parasites. The role of the Zener diode Z1 is to limit the frequency of the oscillator 11 when the device is operating at no load, that is to say when the transistor Q3 is saturated. The Zener diode Z2 determines an upper limit of saturation voltage for the winding 12 d in the case where the transistor Q3 is blocked, which can, for example, be caused by an operation in short-circuit.

Il est à noter que sur le schéma, le sens convenable des bobinages des enroulements du tranformateur 12, les uns par rapport aux autres, est indiqué de façon conventionnelle par des points.It should be noted that in the diagram, the suitable direction of the windings of the windings of the transformer 12, with respect to each other, is indicated conventionally by dots.

Enfin, il est à noter que le dispositif décrit comporte un moyen pour établir des valeurs d'amplitudes différentes entre deux alternances consécutives dudit oscillateur à découpage 11, c'est-à-dire pour créer une différence entre les alternances correspondant respectivement aux conductions des transistors Q1 et Q2. Dans l'exemple décrit, il s'agit d'une simple diode Zener Z3 intercalée entre l'enroulement de saturation 12d et les seconds moyens de redressement 26. De cette façon, la tension "vue" par l'enroulement de saturation 12d est différente d'une alternance à l'autre suivant le sens de la circulation de courant dans la diode Zener Z3.Finally, it should be noted that the device described comprises means for establishing values of different amplitudes between two consecutive half-waves of said switching oscillator 11, that is to say to create a difference between the half-waves corresponding respectively to the conductions of the transistors Q1 and Q2. In the example described, it is a simple Zener diode Z3 interposed between the saturation winding 12 d and the second rectification means 26. In this way, the voltage "seen" by the saturation winding 12 d is different from one alternation to another depending on the direction of current flow in the Zener diode Z3.

Le fonctionnement du dispositif qui vient d'être décrit est le suivant:
Dès que le dispositif est raccordé au réseau alternatif de distribution VAC, l'oscillateur de découpage 11 entre en auto-oscillation, les transistors Q1 et Q2 étant périodiquement commutés sous la commande des enroulements 12b et 12c. Compte tenu du montage, le courant traversant l'enroulement primaire 12a, traverse aussi l'enroulement primaire 13a et la self-induction 15. Conformément au principe de l'invention, la fréquence de l'oscillateur 11 va se stabiliser autour d'une valeur pour laquelle le tube luminescent 14 sera traversé par un courant convenablement choisi, avec régulation de ce dernier. En effet, en fonctionnement, le tube luminescent 14 se comporte pratiquement comme une diode Zener "imposant" la tension à ses bornes, c'est-à-dire aux bornes de l'enroulement secondaire 13b. Cette tension dépend des caractéristiques propres du tube luminescent 14 et notamment de sa longeuer. Il importe donc de réguler le courant traversant le tube 14 pour que celui-ci fonctionne dans des conditions optimales. En effet, si le courant est trop faible, l'éclairage est mauvais et s'il est trop fort, la durée de vie du tube est abrégée.The operation of the device which has just been described is as follows:
As soon as the device is connected to the AC distribution network V AC , the chopping oscillator 11 enters into self-oscillation, the transistors Q1 and Q2 being periodically switched under the control of the windings 12 b and 12 c . Taking into account the assembly, the current passing through the primary winding 12 a , also passes through the primary winding 13 a and the self-induction 15. In accordance with the principle of the invention, the frequency of the oscillator 11 will stabilize around d a value for which the luminescent tube 14 will be traversed by a suitably chosen current, with regulation of the latter. In fact, in operation, the luminescent tube 14 behaves practically like a Zener diode "imposing" the voltage across its terminals, that is to say across the terminals of the secondary winding 13b . This voltage depends on the specific characteristics of the luminescent tube 14 and in particular its length. It is therefore important to regulate the current passing through the tube 14 so that the latter operates under optimal conditions. In fact, if the current is too weak, the lighting is poor and if it is too strong, the life of the tube is shortened.

Les moyens de régulation 16 réalisent la régulation du courant recherchée. En effet, la self-induction 15 limite la variation de courant dans l'enroulement primaire 13a du transformateur 13. Or, la tension aux bornes de l'enroulement primaire 13a imposée par le tube 14 et l'ensemble de la tension d'alimentation disponible se partage entre l'enroulement primaire 13a et la self-induction 15. Par conséquent, si la tension a tendance à augmenter aux bornes de l'enroulement primaire 13a, alors la tension aux bornes de la self-induction 15 a tendance à diminuer. La croissance du courant à chaque alternance a donc également tendance à diminuer. Si on veut maintenir le courant crête dans le tube 14 a une valeur constante, il faut donc conduire plus longtemps à chaque alternance, c'est-à-dire que la fréquence de l'oscillateur 11 doit baisser.The regulation means 16 regulate the current sought. Indeed, the self-induction 15 limits the variation of current in the primary winding 13 a of the transformer 13. Now, the voltage across the terminals of the primary winding 13 a imposed by the tube 14 and all of the voltage d available power is shared between the primary winding 13 a and the self-induction 15. Consequently, if the voltage tends to increase at the terminals of the primary winding 13 a , then the voltage at the terminals of the self-induction 15 tends to decrease. The growth of the current at each half-wave therefore also tends to decrease. If one wants to maintain the peak current in the tube 14 at a constant value, it is therefore necessary to drive longer at each half-wave, that is to say that the frequency of the oscillator 11 must decrease.

C'est précisément ce que réalisent les moyens de régulation 16. En effet, si la tension aux bornes de l'enroulement 13a augmente, il en est de même pour la tension aux bornes de l'enroulement 13c. La tension aux bornes du condensateur C4 augmente alors et la tension entre drain et source du transistor Q3 diminue. Par conséquent, l'enroulement de saturation 12d "voit" une tension diminuer à ses bornes. Dans ces conditions, le circuit magnétique du transformateur 12 va mettre plus de temps à se saturer, entraînant une diminution de la fréquence de fonctionnement.This is precisely what the regulating means 16 do. In fact, if the voltage across the winding 13 a increases, the same goes for the voltage across the winding 13 c . The voltage across the capacitor C4 then increases and the voltage between drain and source of the transistor Q3 decreases. Consequently, the saturation winding 12 d "sees" a voltage decreasing at its terminals. Under these conditions, the magnetic circuit of the transformer 12 will take longer to saturate, resulting in a decrease in the operating frequency.

Les diodes D2 et D3 permettent d'éviter les surtensions lors d'un fonctionnement à vide (c'est-à-dire par exemple lorsque le tube 14 est cassé) en renvoyant l'énergie accumulée dans le transformateur 13 vers l'un des condensateurs C1 ou C2. Par exemple, si c'est le transistor Q2 qui conduit, l'énergie accumulée lorsqu'il se bloque, a tendance à engendrer une surtension entre l'enroulement primaire 13a et la self-inductance 15. Cependant, cette surtension est éliminée par le fait que l'énergie est renvoyée vers le condensateur C1 par la diode D2. Dans ces conditions, l'excursion de tension aux bornes de l'enroulement primaire est limitée à celle du réseau alternatif de distribution et le transformateur 13 est bien entendu calculé pour supporter une telle tension. On conçoit que ce branchement en série de l'enroulement primaire 13a d'un transformateur à couplage élevé 13 avec une self-inductance 15 est l'équivalent d'un transformateur "à fuite", la self-inductance 15 matérialisant en quelque sorte la "self de fuite". Cependant, en utilisant un transformateur "sans fuite" et une inductance séparée, on rend possible le branchement du demi-pont de diodes D2, D3, c'est-à-dire l'élimination des surtensions en fonctionnement à vide. De plus, le fait de séparer le transformateur 13 de la "self de fuite" 15 permet de bien maîtriser le rapport de transformation du transformateur 13. On peut ainsi réaliser un secondaire 13b dit "à prises" comportant des nombres choisis de spires entre une borne commune a et des bornes b, c, d, pour l'alimentation de tubes luminescents différents nécessitant des courants différents. Ainsi, si on considère que les tubes luminescents se classent en trois familles principales en fonction du courant admissible (25mA, 50mA, 100mA) il est possible, à partir d'un seul transformateur 13 et donc d'un seul modèle de dispositif d'alimentation, de couvrir toute la gamme des tubes luminescents.The diodes D2 and D3 make it possible to avoid overvoltages during a no-load operation (that is to say for example when the tube 14 is broken) by returning the energy accumulated in the transformer 13 to one of the capacitors C1 or C2. For example, if it is the transistor Q2 which conducts, the energy accumulated when it blocks, has tendency to generate an overvoltage between the primary winding 13 a and the self-inductance 15. However, this overvoltage is eliminated by the fact that the energy is returned to the capacitor C1 by the diode D2. Under these conditions, the voltage excursion across the terminals of the primary winding is limited to that of the AC distribution network and the transformer 13 is of course calculated to withstand such a voltage. It is understood that this series connection of the primary winding 13 a of a high coupling transformer 13 with a self-inductance 15 is the equivalent of a "leaky" transformer, the self-inductance 15 materializing in a way the "escape self". However, by using a transformer "without leakage" and a separate inductance, it is possible to connect the half-bridge of diodes D2, D3, that is to say the elimination of overvoltages in no-load operation. In addition, the fact of separating the transformer 13 from the “leakage choke” 15 makes it possible to properly control the transformation ratio of the transformer 13. It is thus possible to produce a secondary 13 b known as “with taps” comprising selected numbers of turns between a common terminal a and terminals b , c , d , for supplying different luminescent tubes requiring different currents. Thus, if we consider that the luminescent tubes are classified into three main families according to the admissible current (25mA, 50mA, 100mA) it is possible, from a single transformer 13 and therefore from a single model of device power supply, to cover the whole range of luminescent tubes.

La figure 2 illustre une variante dans laquelle le transistor Q3 est remplacé par une diode Zener ajustable Z4. L'entrée de commande de cette diode est connectée au curseur du potentiomètre P1 tandis qu'une résistance R1 établit une contre-réaction entre le point commun des diodes Z1 et Z2 et ladit entrée de commande de la diode Z4. Cette dernière est équivalente à un amplificateur opérationnel à référence intégrée.FIG. 2 illustrates a variant in which the transistor Q3 is replaced by an adjustable Zener diode Z4. The control input of this diode is connected to the cursor of the potentiometer P1 while a resistor R1 establishes a feedback between the common point of the diodes Z1 and Z2 and the said control input of the diode Z4. The latter is equivalent to an operational amplifier with integrated reference.

Claims (12)

1- Dispositif d'alimentation de tube luminescent, caractérisé en ce qu'il comprend:
- un oscillateur à découpage (11), à fréquence variable comportant un premier transformateur (12) muni d'un enroulement primaire (12a) et d'un enroulement de saturation (12d),
- un second transformateur (13), comportant un enroulement primaire (13a) dont une extrémité est reliée audit enroulement primaire (12a) dudit premier transformateur, un enroulement secondaire (13b) prévu pour être connecté audit tube luminescent (14) et un enroulement de référence (13c), et
- des moyens de régulation (16) agencés entre ledit enroulement de référence et ledit enroulement de saturation pour réguler le courant traversant ledit tube luminescent (14) en faisant varier la fréquence de fonctionnement dudit oscillateur.1- Luminescent tube supply device, characterized in that it comprises:
- a switching oscillator (11), with variable frequency comprising a first transformer (12) provided with a primary winding (12 a ) and a saturation winding (12 d ),
a second transformer (13), comprising a primary winding (13 a ), one end of which is connected to said primary winding (12 a ) of said first transformer, a secondary winding (13 b ) intended to be connected to said luminescent tube (14) and a reference winding (13 c ), and
- regulation means (16) arranged between said reference winding and said saturation winding to regulate the current passing through said luminescent tube (14) by varying the operating frequency of said oscillator. 2- Dispositif selon la revendication 1, caractérisé en ce que les enroulements dudit second transformateur sont à couplage élevé et en ce que son enroulement primaire est relié à l'enroulement primaire (12a) dudit premier transformateur par l'intermédiaire d'une self-induction (15).2- Device according to claim 1, characterized in that the windings of said second transformer are high coupling and in that its primary winding is connected to the primary winding (12 a ) of said first transformer via a choke -induction (15). 3- Dispositif selon la revendication 1 ou 2, caractérisé en ce que les moyens de régulation (16) précités comportent des premiers moyens de redressement (D4) connectés audit enroulement de référence, des seconds moyens de redressement (26) connectés audit enroulement de saturation et une circuit de charge (30) desdits seconds moyens de redressement comportant un composant semi-conducteur (Q3) développant à ses bornes une tension représentative de la tension élaborée par lesdits premiers moyens de redressement.3- Device according to claim 1 or 2, characterized in that the aforementioned regulation means (16) comprise first rectifying means (D4) connected to said reference winding, second rectifying means (26) connected to said saturation winding and a charging circuit (30) of said second rectifying means comprising a semiconductor component (Q3) developing at its terminals a voltage representative of the voltage produced by said first rectifying means. 4- Dispositif selon la revendication 3, caractérisé en ce que ledit circuit de charge (30) comprend un montage en série d'une première diode Zener (Z1) et du composant semi-conducteur (Q3) précité.4- Device according to claim 3, characterized in that said charging circuit (30) comprises an assembly in series with a first Zener diode (Z1) and the aforementioned semiconductor component (Q3). 5- Dispositif selon la revendication 3 ou 4, caractérisé en ce que ledit composant semi-conducteur est un transistor (Q3) dont l'entrée de commande est reliée audit premier moyen de redressement.5- Device according to claim 3 or 4, characterized in that said semiconductor component is a transistor (Q3) whose control input is connected to said first rectifying means. 6- Dispositif selon la revendication 5, caractérisé en ce que ledit transistor (Q3) est un transistor à effet de champ, dont la liaison drain-source est en série avec ladite diode Zener (Z1).6- Device according to claim 5, characterized in that said transistor (Q3) is a field effect transistor, whose drain-source link is in series with said Zener diode (Z1). 7- Dispositif selon la revendication 5 ou 6, caractérisé en ce qu'une seconde diode Zener (Z2) est connectée en parallèle sur ledit transistor (Q3).7- Device according to claim 5 or 6, characterized in that a second Zener diode (Z2) is connected in parallel on said transistor (Q3). 8- Dispositif selon l'une des revendications précédentes, caractérisé en ce qu'il comporte un moyen (Z3) pour établir des valeurs d'amplitude différentes entre deux alternances consécutives dudit oscillateur de découpage.8- Device according to one of the preceding claims, characterized in that it comprises means (Z3) for establishing different amplitude values between two consecutive half-waves of said cutting oscillator. 9- Dispositif selon l'ensemble des revendications 3 et 7, caractérisé en ce que ce moyen consiste en une diode Zener (Z3) intercalée entre ledit enroulement de saturation (12d) et lesdits seconds moyens de redressement (26).9- Device according to all of claims 3 and 7, characterized in that this means consists of a Zener diode (Z3) interposed between said saturation winding (12 d ) and said second rectifying means (26). 10- Dispositif selon l'une des revendications précédentes, caractérisé en ce que ledit oscillateur comporte deux demi-ponts oscillants, respectivement un demi-pont de composants semi-conducteurs (Q1, Q2) connecté aux bornes d'une source de tension d'alimentation (19,20), dont les entrées de commande sont reliées à des enroulements secondaires (12b, 12c) dudit premier transformateur (12) et un demi-pont de condensateurs (C1, C2) connecté aux bornes de ladit source de tension d'alimentation (19, 20) et dont le point milieu est relié à une seconde extrémité de l'enroulement primaire (13a) dudit second transformateur.10- Device according to one of the preceding claims, characterized in that said oscillator comprises two oscillating half-bridges, respectively a half-bridge of semiconductor components (Q1, Q2) connected across the terminals of a voltage source of power supply (19,20), whose control inputs are connected to secondary windings (12 b , 12 c ) of said first transformer (12) and a half-bridge of capacitors (C1, C2) connected to the terminals of said source of supply voltage (19, 20) and the midpoint of which is connected to a second end of the primary winding (13 a ) of said second transformer. 11- Dispositif selon l'ensemble des revendications 2 et 10, caractérisé en ce qu'il comporte un demi-pont de diodes (D2, D3) en série, connecté en inverse à ladite source de tension d'alimentation (19, 20) et dont le point milieu est connecté à la liaison établie entre ladite self-induction (15) et ladite première extrémité de l'enroulement primaire (13a) dudit second transformateur.11- Device according to all of claims 2 and 10, characterized in that it comprises a half-bridge of diodes (D2, D3) in series, connected in reverse to said supply voltage source (19, 20) and whose midpoint is connected to the link established between said self-induction (15) and said first end of the primary winding (13 a ) of said second transformer. 12- Dispositif selon l'une des revendications précédentes, caractérisé en ce que ledit enroulement secondaire (13b) dudit second transformateur comporte un nombre choisi de spires entre une borne commune (a) et des bornes (b, c, d) pour l'alimentation de tubes luminescents différents.12- Device according to one of the preceding claims, characterized in that said secondary winding (13 b ) of said second transformer comprises a chosen number of turns between a common terminal ( a ) and terminals ( b , c , d ) for l supply of different luminescent tubes.
EP89400338A 1988-02-16 1989-02-07 Supplying device for a luminescent tube Withdrawn EP0340049A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8801798 1988-02-16
FR8801798A FR2627342B1 (en) 1988-02-16 1988-02-16 LUMINESCENT TUBE FEEDING DEVICE

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EP0340049A1 true EP0340049A1 (en) 1989-11-02

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FR (1) FR2627342B1 (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0417315A1 (en) * 1989-03-27 1991-03-20 Toshiba Lighting & Technology Corporation Device for lighting a discharge lamp
WO1991007863A1 (en) * 1989-11-18 1991-05-30 Ac/Dc Lighting Limited Inverters and cathode lamp arrangements
EP0479352A1 (en) * 1990-09-14 1992-04-08 Koninklijke Philips Electronics N.V. Converter for discharge lamps with dimming means
EP0577975A1 (en) * 1992-07-06 1994-01-12 LESTICIAN BALLAST Inc. Variable control, current sensing ballast
EP0580255A1 (en) * 1992-07-20 1994-01-26 Koninklijke Philips Electronics N.V. DC-AC converter with protection means, for supplying a discharge lamp
EP0948245A2 (en) * 1998-03-31 1999-10-06 General Electric Company Dimmable ballast with complementary converter switches
WO2000024233A2 (en) * 1998-10-16 2000-04-27 Electro-Mag International, Inc. Ballast circuit
US6169375B1 (en) 1998-10-16 2001-01-02 Electro-Mag International, Inc. Lamp adaptable ballast circuit
EP1073317A2 (en) * 1999-07-26 2001-01-31 Lestec. Co., Ltd. Ballast for discharge lamp
WO2009108441A1 (en) * 2008-02-29 2009-09-03 General Electric Company Dimmable instant start ballast
US7990070B2 (en) 2009-06-05 2011-08-02 Louis Robert Nerone LED power source and DC-DC converter
US8212498B2 (en) 2009-02-23 2012-07-03 General Electric Company Fluorescent dimming ballast
CN103098358A (en) * 2010-03-26 2013-05-08 拉塞尔·雅克 Regulating controller for controlled self-oscillating converters using bipolar junction transistors
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0389493A (en) * 1989-08-31 1991-04-15 Toshiba Lighting & Technol Corp Lighting device for discharge lamp
DE4436465A1 (en) * 1994-10-12 1996-04-18 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Circuit arrangement for operating incandescent lamps
US5761056A (en) * 1997-02-20 1998-06-02 Boam R & D Co., Ltd. Circuit for protecting fluorescent lamp from overload
US6072710A (en) * 1998-12-28 2000-06-06 Philips Electronics North America Corporation Regulated self-oscillating resonant converter with current feedback
US6111363A (en) * 1999-07-21 2000-08-29 General Electric Company Ballast shutdown circuit for a gas discharge lamp
US7733028B2 (en) 2007-11-05 2010-06-08 General Electric Company Method and system for eliminating DC bias on electrolytic capacitors and shutdown detecting circuit for current fed ballast

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0075176A2 (en) * 1981-09-18 1983-03-30 Oy Helvar Electronic ballast for a discharge lamp
GB2119184A (en) * 1982-04-21 1983-11-09 Helvar Oy High frequency current supply method and apparatus
EP0178852A1 (en) * 1984-10-16 1986-04-23 ADVANCE TRANSFORMER CO. (a Division of Philips Electronics North America Corporation) Electronic ballast circuit for fluorescent lamps
US4727470A (en) * 1986-10-10 1988-02-23 Nilssen Ole K Resonant inverter having crest factor control

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0075176A2 (en) * 1981-09-18 1983-03-30 Oy Helvar Electronic ballast for a discharge lamp
GB2119184A (en) * 1982-04-21 1983-11-09 Helvar Oy High frequency current supply method and apparatus
EP0178852A1 (en) * 1984-10-16 1986-04-23 ADVANCE TRANSFORMER CO. (a Division of Philips Electronics North America Corporation) Electronic ballast circuit for fluorescent lamps
US4727470A (en) * 1986-10-10 1988-02-23 Nilssen Ole K Resonant inverter having crest factor control
US4727470B1 (en) * 1986-10-10 1992-06-30 K Nilssen Ole

Cited By (24)

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EP0417315A4 (en) * 1989-03-27 1993-03-10 Toshiba Lighting & Technology Corporation Device for lighting a discharge lamp
EP0417315A1 (en) * 1989-03-27 1991-03-20 Toshiba Lighting & Technology Corporation Device for lighting a discharge lamp
WO1991007863A1 (en) * 1989-11-18 1991-05-30 Ac/Dc Lighting Limited Inverters and cathode lamp arrangements
EP0479352A1 (en) * 1990-09-14 1992-04-08 Koninklijke Philips Electronics N.V. Converter for discharge lamps with dimming means
US5172033A (en) * 1990-09-14 1992-12-15 U. S. Philips Corporation Discharge lamp operating inverter circuit with electric dimmer utilizing frequency control of the inverter
USRE35994E (en) * 1992-07-06 1998-12-15 Icecap, Inc. Variable control, current sensing ballast
EP0577975A1 (en) * 1992-07-06 1994-01-12 LESTICIAN BALLAST Inc. Variable control, current sensing ballast
EP0580255A1 (en) * 1992-07-20 1994-01-26 Koninklijke Philips Electronics N.V. DC-AC converter with protection means, for supplying a discharge lamp
EP0948245A2 (en) * 1998-03-31 1999-10-06 General Electric Company Dimmable ballast with complementary converter switches
EP0948245A3 (en) * 1998-03-31 2001-05-02 General Electric Company Dimmable ballast with complementary converter switches
WO2000024233A2 (en) * 1998-10-16 2000-04-27 Electro-Mag International, Inc. Ballast circuit
WO2000024233A3 (en) * 1998-10-16 2000-09-21 Electro Mag Int Inc Ballast circuit
US6169375B1 (en) 1998-10-16 2001-01-02 Electro-Mag International, Inc. Lamp adaptable ballast circuit
EP1073317A2 (en) * 1999-07-26 2001-01-31 Lestec. Co., Ltd. Ballast for discharge lamp
EP1073317A3 (en) * 1999-07-26 2002-07-31 Lestec. Co., Ltd. Ballast for discharge lamp
EP1707256B1 (en) 2003-03-21 2016-10-19 Kemira Oyj Device and method for continuously producing emulsions or dispersions
WO2009108441A1 (en) * 2008-02-29 2009-09-03 General Electric Company Dimmable instant start ballast
US7816872B2 (en) 2008-02-29 2010-10-19 General Electric Company Dimmable instant start ballast
CN101960924A (en) * 2008-02-29 2011-01-26 通用电气公司 Tunable optical instantaneous starting ballast
CN101960924B (en) * 2008-02-29 2014-07-02 通用电气公司 Dimmable instant start ballast
US8212498B2 (en) 2009-02-23 2012-07-03 General Electric Company Fluorescent dimming ballast
US7990070B2 (en) 2009-06-05 2011-08-02 Louis Robert Nerone LED power source and DC-DC converter
CN103098358A (en) * 2010-03-26 2013-05-08 拉塞尔·雅克 Regulating controller for controlled self-oscillating converters using bipolar junction transistors
CN103098358B (en) * 2010-03-26 2016-03-30 拉塞尔·雅克 Use the conditioning controller of the self-oscillation current transformer of bipolar junction transistor

Also Published As

Publication number Publication date
FR2627342A1 (en) 1989-08-18
FR2627342B1 (en) 1990-07-20

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