EP0437838A1 - Reactance circuit breaker for low excess voltage - Google Patents

Reactance circuit breaker for low excess voltage Download PDF

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Publication number
EP0437838A1
EP0437838A1 EP90125539A EP90125539A EP0437838A1 EP 0437838 A1 EP0437838 A1 EP 0437838A1 EP 90125539 A EP90125539 A EP 90125539A EP 90125539 A EP90125539 A EP 90125539A EP 0437838 A1 EP0437838 A1 EP 0437838A1
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EP
European Patent Office
Prior art keywords
circuit breaker
reactance
circuit
varistor
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.)
Withdrawn
Application number
EP90125539A
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German (de)
French (fr)
Inventor
Edmond Thuries
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.)
Alstom Holdings SA
Original Assignee
GEC Alsthom SA
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Filing date
Publication date
Application filed by GEC Alsthom SA filed Critical GEC Alsthom SA
Publication of EP0437838A1 publication Critical patent/EP0437838A1/en
Withdrawn legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/02—Details
    • H01H33/04—Means for extinguishing or preventing arc between current-carrying parts
    • H01H33/16—Impedances connected with contacts
    • H01H33/161—Variable impedances
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
    • H01H33/02—Details
    • H01H33/59—Circuit arrangements not adapted to a particular application of the switch and not otherwise provided for, e.g. for ensuring operation of the switch at a predetermined point in the ac cycle
    • H01H33/593—Circuit arrangements not adapted to a particular application of the switch and not otherwise provided for, e.g. for ensuring operation of the switch at a predetermined point in the ac cycle for ensuring operation of the switch at a predetermined point of the ac cycle

Definitions

  • the present invention relates to a reactance circuit breaker with low overvoltages.
  • the constraints on the reactance are on the one hand the amplitude of the overvoltage, especially following a reboot in the circuit breaker, and, on the other hand, the speed of increase of the overvoltage; this speed depends on the frequency of oscillation of the busbar circuit. This latter constraint is harmful to wound windings; these voltage waves are called cut waves.
  • the operating threshold of the varistors cannot be set below 1.5 to 1.6 p.u. without risking overheating the varistor in continuous operation to 1 p.u. , unless using a switch in series with the varistor.
  • An object of the invention is to provide a reactance circuit breaker with low overvoltages.
  • the present invention relates to a reactance circuit breaker comprising for each phase at least one breaking chamber, provided with an operating member, and at least one varistor across the terminals of said breaking chamber, characterized in that said operating member is dependent on an ordering circuit to allow an opening ensuring a sufficient arc duration to avoid any re-ignition at the terminals of said chamber.
  • said varistor has an operating value of between 1.5 and 1.7 p.u.
  • the reference 1 designates a switching chamber disposed at the end of a support 2 and operated by an operating member 3.
  • the circuit breaker is in series in circuit 4 with a reactance 5.
  • a varistor 6 is connected across the switching chamber.
  • the circuit breaker is controlled by a circuit 8 initiator of synchronized opening; the latter receives voltage information, for example by a capacitive divider C1, C2, and current information, for example by means of a current transformer 9. From these data, the originator prepares a tripping order at a time chosen to ensure sufficient arcing time to avoid re-striking in the circuit breaker.
  • the presence of the varistor protects the circuit breaker against any voltage overload exceeding the operating threshold of the varistor.
  • any excessively tearing of the current to be cut can create a high overvoltage; moreover, rain or snow can overload in voltage one or more of the interrupting chambers of a given phase.
  • the operating voltage threshold of the varistor can usefully be set between 1.5 and 1.7 p.u.
  • This voltage threshold will be determined according to the dielectric behavior between input and output of the circuit breaker and not that of the reactance.
  • the invention finds application in the equipment of high voltage electrical networks.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Arc-Extinguishing Devices That Are Switches (AREA)
  • Circuit Breakers (AREA)
  • Breakers (AREA)

Abstract

The subject is a reactance circuit-breaker comprising for each phase at least one disconnection chamber, provided with an operating member, and at least one varistor across the terminals of the said disconnection chamber, characterised in that the said operating member (3) is under the dependence of a circuit (8) giving an order, so as to permit an opening ensuring an arc duration sufficient to preclude any reenergization across the terminals of the said chamber. Application to the equipment of high-voltage electrical circuits. <IMAGE>

Description

La présente invention concerne un disjoncteur de réactance à faibles surtensions.The present invention relates to a reactance circuit breaker with low overvoltages.

ETAT DE LA TECHNIQUESTATE OF THE ART

La coupure d'une réactance shunt à haute tension (ou la coupure de tout autre circuit inductif) crée des contraintes à la fois sur la réactance et sur le disjoncteur.The interruption of a high voltage shunt reactance (or the interruption of any other inductive circuit) creates stresses both on the reactance and on the circuit breaker.

Les contraintes sur la réactance sont d'une part l'amplitude de la surtension, surtout suite à un réamorçage dans le disjoncteur, et, d'autre part, la vitesse d'accroissement de la surtension; cette vitesse dépend de la fréquence d'oscillation du circuit du jeu de barres. Cette dernière contrainte est néfaste aux enroulement bobinés; on appelle ces ondes de tension des ondes coupées.The constraints on the reactance are on the one hand the amplitude of the overvoltage, especially following a reboot in the circuit breaker, and, on the other hand, the speed of increase of the overvoltage; this speed depends on the frequency of oscillation of the busbar circuit. This latter constraint is harmful to wound windings; these voltage waves are called cut waves.

Dans le rapport "High frequency switching surges in EHV shunt reactor installation with reduced insulation levels", F-78 659-5, IEEE PES, Juillet 1978, Los Angeles, il a été signalé des surtensions de 2,3 p.u. et des fréquences de 300 kHz mesurées sur un circuit de réactance à 500 kV de la BPA (Bonneville Power Administration, Etats-Unis). Le du/dt obtenu est de l'ordre de 560 Kilovolts par microsecondes.In the report "High frequency switching surges in EHV shunt reactor installation with reduced insulation levels", F-78 659-5, IEEE PES, July 1978, Los Angeles, overvoltages of 2.3 p.u were reported. and frequencies of 300 kHz measured on a reactance circuit at 500 kV of the BPA (Bonneville Power Administration, United States). The du / dt obtained is of the order of 560 Kilovolts per microseconds.

D'après ce rapport, la conception de la réactance a permis à cette dernière de supporter sans difficulté toutes ces contraintes.According to this report, the design of the reactance enabled the latter to easily withstand all these constraints.

Dans le rapport "La coupure des courants inductifs des réactances shunt à extra-haute tension", CIGRE 1978, rapport No 13-06, des ondes de surtension de durée de front de quelques microsecondes ont été mesurées sur les réseaux 500 kV et 750 kV soviétiques.In the report "The cutoff current of the inductive reactances shunt extra high voltage", CIGRE, 1978, report No. 13-06, of a few microseconds front time of surge waves were measured on the networks 500 and 750 kV Soviet kV.

Dans le rapport "Problèmes particuliers de coupure des circuits industriels et leur solution par l'emploi de résistances d'amortissement non linéaires", Conférence CIRED Mai 1977, Londres, Rapport No6-4, il est précisé que, selon que le neutre du circuit est isolé ou à la terre, on peut obtenir des surtensions plus ou moins élevées. Avec un neutre isolé, la surtension peut atteindre 4 à 5 p.u. suite à des réamorçages dans le disjoncteur. Les auteurs ont fortement conseillé l'utilisation des résistances non linéaires pour éviter les réamorçages dans les disjoncteurs et les variations rapides de tension qui en découlent.In the report "Particular problems of interruption of industrial circuits and their solution by the use of nonlinear damping resistors ", CIRED Conference May 1977, London, Report N o 6-4, it is specified that, depending on whether the neutral of the circuit is isolated or to earth, more or less high overvoltages can be obtained. With an isolated neutral, the overvoltage can reach 4 to 5 pu following restrikes in the circuit breaker.The authors strongly recommended the use of non-linear resistors to avoid restrikes in the circuit breakers and the rapid voltage variations which result from this.

Les contraintes sur le disjoncteur sont, pour une tension aux bornes du disjoncteur trop élevée suite à un arrachage de courant trop important par exemple,

  • soit un amorçage interne
  • soit des contournements externes, qui ont déjà entraîné des explosions de disjoncteurs, si les conditions atmosphériques sont défavorables (neige, pluie entraînant une mauvaise répartition de la tension sur le disjoncteur, en particulier dans le cas d'un disjoncteur à plusieurs chambres).
The constraints on the circuit breaker are, for a voltage at the terminals of the circuit breaker that is too high following too much current tearing, for example,
  • either an internal boot
  • or external bypasses, which have already caused circuit breaker explosions, if the atmospheric conditions are unfavorable (snow, rain causing poor distribution of the voltage on the circuit breaker, in particular in the case of a circuit breaker with several chambers).

Pour réduire l'amplitude des surtensions sur la réactance, on peut soit utiliser des parafoudres aux bornes de la réactance, soit empêcher des réamorçages dans le disjoncteur, surtout des réamorçages hauts qui entraînent des surtensions élevées.To reduce the amplitude of overvoltages on the reactance, it is possible either to use surge arresters at the terminals of the reactance, or to prevent restrikes in the circuit breaker, especially high strikes which cause high overvoltages.

Dans le rapport cité en dernier lieu et dans le rapport "Disjoncteurs sans surtensions", CIGRE, 1958, rapport No 146, on a proposé d'utiliser des résistances variables ou non linéaires aux bornes du disjoncteur pour limiter les surtensions.In the report quoted last and in the report "Circuit breakers without surges", CIGRE, 1958 Report No. 146, it was proposed to use variable resistors or nonlinear across the circuit breaker to limit surges.

Dans le brevet allemand 2 361 203 du 12 juin 1975 (Siemens), on a proposé des résistances non linéaires à oxydes métalliques de type ZnO.In German patent 2,361,203 of June 12, 1975 (Siemens), non-linear resistors of metal oxides of the ZnO type have been proposed.

L'utilisation de l'oxyde de zinc permet de s'affranchir d'un interrupteur série, étant donné le coefficient de non linéarité élevé, de l'ordre de 50 à comparer à 6 pour le carbure de silicium.The use of zinc oxide makes it possible to dispense with a series switch, given the high coefficient of non-linearity, of the order of 50 to be compared to 6 for silicon carbide.

Ceci permet d'obtenir un courant de suite très faible à la tension permanente de fonctionnement de 1 p.u.This allows a very low follow-up current to be obtained at the permanent operating voltage of 1 p.u.

Plus la tension de fonctionnement de la varistance est faible, plus la protection sera efficace.The lower the operating voltage of the varistor, the more effective the protection will be.

Dans l'état actuel des performances des oxydes de zinc, on ne peut pas fixer le seuil de fonctionnement des varistances au-dessous de 1,5 à 1,6 p.u. sans risquer d'échauffer exagérément la varistance en fonctionnement permanent à 1 p.u. , à moins d'utiliser un interrupteur en série avec la varistance.In the current state of performance of zinc oxides, the operating threshold of the varistors cannot be set below 1.5 to 1.6 p.u. without risking overheating the varistor in continuous operation to 1 p.u. , unless using a switch in series with the varistor.

Pour éviter l'amorçage dans le disjoncteur, lequel entraîne l'usure des contacts et de la buse isolante de soufflage, et crée des ondes à front raide dans le circuit à réactance, les auteurs du rapport CIGRE 13-06 de 1978 cité plus haut ont proposé d'utiliser l'ouverture synchronisée du disjoncteur afin d'éviter les temps d'arc courts, c'est-à-dire des distances faibles entre contacts.To avoid priming in the circuit breaker, which causes wear of the contacts and of the insulating blowing nozzle, and creates steep-front waves in the reactance circuit, the authors of the report CIGRE 13-06 of 1978 cited above proposed to use the synchronized opening of the circuit breaker in order to avoid short arcing times, that is to say short distances between contacts.

Il s'agit de synchroniser l'ouverture du disjoncteur avec le début de l'onde de courant à fréquence industrielle dans le but d'obtenir des temps d'arc de coupure longs.This involves synchronizing the opening of the circuit breaker with the start of the industrial frequency current wave in order to obtain long breaking arc times.

En détectant la tension d'alimentation de la réactance et en tenant compte de la durée d'ouverture du disjoncteur, on peut aussi synchroniser l'ouverture du disjoncteur avec l'onde de tension pour avoir des temps d'arc longs, sachant que le courant est en quadrature avec la tension.By detecting the supply voltage of the reactance and taking into account the duration of opening of the circuit breaker, one can also synchronize the opening of the circuit breaker with the voltage wave to have long arc times, knowing that the current is quadrature with voltage.

BUT DE L'INVENTIONPURPOSE OF THE INVENTION

Un but de l'invention est de réaliser un disjoncteur de réactance à faibles surtensions.An object of the invention is to provide a reactance circuit breaker with low overvoltages.

OBJET DE L' INVENTIONOBJECT OF THE INVENTION

La présente invention à pour objet un disjoncteur de réactance comprenant pour chaque phase au moins une chambre de coupure, munie d'un organe de manoeuvre, et au moins une varistance aux bornes de ladite chambre de coupure, caractérisé en ce que ledit organe de manoeuvre est sous la dépendance d'un circuit donneur d'ordre pour permettre une ouverture assurant une durée d'arc suffisante pour éviter tout réamorçage aux bornes de ladite chambre.The present invention relates to a reactance circuit breaker comprising for each phase at least one breaking chamber, provided with an operating member, and at least one varistor across the terminals of said breaking chamber, characterized in that said operating member is dependent on an ordering circuit to allow an opening ensuring a sufficient arc duration to avoid any re-ignition at the terminals of said chamber.

Avantageusement, ladite varistance a une valeur de fonctionnement comprise entre 1,5 et 1,7 p.u.Advantageously, said varistor has an operating value of between 1.5 and 1.7 p.u.

DESCRIPTION D'UN MODE PREFERE DE REALISATIONDESCRIPTION OF A PREFERRED EMBODIMENT

L'invention est précisée par la description d'un mode préféré de réalisation, en référence au dessin annexé dans lequel la figure unique est une vue schématique d'une phase du disjoncteur de l'invention et de la réactance associée.The invention is clarified by the description of a preferred embodiment, with reference to the appended drawing in which the single figure is a schematic view of a phase of the circuit breaker of the invention and of the associated reactance.

Dans la figure, la référence 1 désigne une chambre de coupure disposée à l'extrémité d'un support 2 et manoeuvrée par un organe de manoeuvre 3. Le disjoncteur est en série dans le circuit 4 avec une réactance 5. Une varistance 6 est connectée aux bornes de la chambre de coupure.In the figure, the reference 1 designates a switching chamber disposed at the end of a support 2 and operated by an operating member 3. The circuit breaker is in series in circuit 4 with a reactance 5. A varistor 6 is connected across the switching chamber.

Selon l'invention, le disjoncteur est commandé par un circuit 8 donneur d'ordre d'ouverture synchronisée; ce dernier reçoit des informations de tension, par exemple par un diviseur capacitif C1,C2, et des informations de courant, par exemple grâce à un transformateur de courant 9. A partir de ces données, le donneur d'ordre élabore un ordre de déclenchement à un instant choisi pour assurer un temps d'arc suffisant pour éviter tout réamorçage dans le disjoncteur.According to the invention, the circuit breaker is controlled by a circuit 8 initiator of synchronized opening; the latter receives voltage information, for example by a capacitive divider C1, C2, and current information, for example by means of a current transformer 9. From these data, the originator prepares a tripping order at a time chosen to ensure sufficient arcing time to avoid re-striking in the circuit breaker.

La présence de la varistance permet de protéger le disjoncteur contre toute surcharge de tension dépassant le seuil de fonctionnement de la varistance.The presence of the varistor protects the circuit breaker against any voltage overload exceeding the operating threshold of the varistor.

On note que tout arrachage trop important du courant à couper peut créer une surtension élevée; par ailleurs, la pluie ou la neige peuvent surcharger en tension l'une ou plusieurs des chambres de coupure d'une phase donnée.It is noted that any excessively tearing of the current to be cut can create a high overvoltage; moreover, rain or snow can overload in voltage one or more of the interrupting chambers of a given phase.

Puisqu'il n'y a plus de réamorçage dans le disjoncteur, le seuil de tension de fonctionnement de la varistance peut être fixé utilement entre 1,5 et 1,7 p.u.Since there is no longer a reboot in the circuit breaker, the operating voltage threshold of the varistor can usefully be set between 1.5 and 1.7 p.u.

Ce seuil de tension sera déterminé en fonction du comportement diélectrique entre entrée et sortie du disjoncteur et non celui de la réactance.This voltage threshold will be determined according to the dielectric behavior between input and output of the circuit breaker and not that of the reactance.

L'invention trouve application dans l'équipement des réseaux électriques à haute tension.The invention finds application in the equipment of high voltage electrical networks.

Claims (2)

Disjoncteur de réactance comprenant pour chaque phase au moins une chambre de coupure, munie d'un organe de manoeuvre, et au moins une varistance aux bornes de ladite chambre de coupure, caractérisé en ce que ledit organe de manoeuvre (3) est sous la dépendance d'un circuit donneur d'ordre (8) pour permettre une ouverture assurant une durée d'arc suffisante pour éviter tout réamorçage aux bornes de ladite chambre.Reactor circuit breaker comprising for each phase at least one breaking chamber, provided with an operating member, and at least one varistor at the terminals of said breaking chamber, characterized in that said operating member (3) is under dependence an ordering circuit (8) to allow an opening ensuring a sufficient arc duration to avoid any re-ignition across said chamber. Disjoncteur selon la revendication 1, caractérisé en ce que ladite varistance (6) a une valeur de fonctionnement comprise entre 1,5 et 1,7 p.u.Circuit breaker according to claim 1, characterized in that said varistor (6) has an operating value between 1.5 and 1.7 p.u.
EP90125539A 1990-01-17 1990-12-27 Reactance circuit breaker for low excess voltage Withdrawn EP0437838A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9000492A FR2657194B1 (en) 1990-01-17 1990-01-17 LOW-SURGE REACTOR CIRCUIT BREAKER.
FR9000492 1990-01-17

Publications (1)

Publication Number Publication Date
EP0437838A1 true EP0437838A1 (en) 1991-07-24

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EP90125539A Withdrawn EP0437838A1 (en) 1990-01-17 1990-12-27 Reactance circuit breaker for low excess voltage

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EP (1) EP0437838A1 (en)
JP (1) JPH04218220A (en)
CN (1) CN1023358C (en)
BR (1) BR9100175A (en)
CA (1) CA2034305C (en)
FR (1) FR2657194B1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2688623A1 (en) * 1992-03-13 1993-09-17 Asea Brown Boveri Reactor switch
WO2005117049A1 (en) * 2004-05-26 2005-12-08 Electro Magnetic Rams Limited Switchgear system

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103578843A (en) * 2013-11-08 2014-02-12 西安盟创电器有限公司 Non-reignition disconnector

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1926972A1 (en) * 1969-05-23 1970-11-26 Siemens Ag Switching device for current limitation
DE2361203A1 (en) * 1973-12-06 1975-06-12 Siemens Ag Power cct. breaker with arc quenching - has relatively moving contacts forming switching path with parallel resistors
FR2506067A1 (en) * 1981-05-15 1982-11-19 Alsthom Atlantique High voltage circuit breaker - where main switch has by=pass circuit contg. rows of resistors employed to quench arc when switch is opened
FR2592521A1 (en) * 1985-12-27 1987-07-03 Gen Electric Fault current switch eliminating arcing

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4830058A (en) * 1971-08-24 1973-04-20
JPS58121519A (en) * 1982-01-12 1983-07-19 株式会社日立製作所 Breaker with resistance contact

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1926972A1 (en) * 1969-05-23 1970-11-26 Siemens Ag Switching device for current limitation
DE2361203A1 (en) * 1973-12-06 1975-06-12 Siemens Ag Power cct. breaker with arc quenching - has relatively moving contacts forming switching path with parallel resistors
FR2506067A1 (en) * 1981-05-15 1982-11-19 Alsthom Atlantique High voltage circuit breaker - where main switch has by=pass circuit contg. rows of resistors employed to quench arc when switch is opened
FR2592521A1 (en) * 1985-12-27 1987-07-03 Gen Electric Fault current switch eliminating arcing

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2688623A1 (en) * 1992-03-13 1993-09-17 Asea Brown Boveri Reactor switch
WO2005117049A1 (en) * 2004-05-26 2005-12-08 Electro Magnetic Rams Limited Switchgear system

Also Published As

Publication number Publication date
BR9100175A (en) 1991-10-22
CN1023358C (en) 1993-12-29
FR2657194A1 (en) 1991-07-19
CA2034305C (en) 1997-02-11
JPH04218220A (en) 1992-08-07
CA2034305A1 (en) 1991-07-18
FR2657194B1 (en) 1993-12-31
CN1056373A (en) 1991-11-20

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