EP1369888A1 - Hybrid circuit breaker for middle or high voltage with vacuum and gas - Google Patents

Abstract

A gas circuit breaker (40) is connected in series with a vacuum circuit breaker and both are housed within an envelope containing an insulating gas. An operating rod (6) is attached to one of the gas circuit breaker contacts and a main spring (20) is restricted by stop rods (14'A) to allow for dead travel (D). A second spring (21) causes the vacuum circuit breaker contacts to open at the end of the dead travel

Description

The invention relates to a hybrid type switching device for high or medium voltage. The hybrid qualifier applies to the cut which is of mixed type in making two different cutting techniques cooperate. We notably describe as hybrid a switch device which comprises a vacuum switch containing a first pair of arcing contacts and which also includes a gas switch comprising a second pair of arcing contacts.

A device of this type is known from US Pat. No. 3,038,980. It comprises a envelope filled with a dielectric gas and having a longitudinal axis, inside which are arranged the two switches electrically connected in series and to the exterior of which is arranged the control mechanism of the device. The mechanism actuation of the contacts of the two switches is relatively simple, in the sense that one of the two contacts of the gas switch is integral with a movable contact which is attached to it adjacent to the vacuum switch. The other contact of the gas switch is secured to a operating rod connected to the device control mechanism. A mechanism to spring associated with a stop has the effect of keeping the contacts pressed against each other of the gas switch during the first part of their stroke when opening the device, until the vacuum switch contacts are separated by a distance determined. The purpose of such a sequence for the separation of the contacts of the two pairs is to be able to delay the separation of the contacts of the second pair (gas switch) by compared to those of the first pair (vacuum switch).

However, such a sequence is not satisfactory if the cut-off device high voltage hybrid combines a gas switch designed for high voltage standardized above 72.5 kV with a vacuum interrupter designed for an average normalized voltage less than 52 kV. Indeed, as long as the contacts of the gas switch are not separated during the process of breaking a fault current by the device, the vacuum interrupter supports all the transient recovery voltage across the breaking device during the separation of its contacts. However, the vacuum switch is not provided that to withstand a recovery voltage which remains within the limits of the medium voltage. Thus, a high voltage hybrid switching device which would work the sequence described above for the separation of the contacts could not cut the current only after separation of the two contacts of the gas switch. This operation involves a relatively long arc duration that a vacuum interrupter is not designed to support. The general structure of the device described in this patent US 3038980 does not allow no ability to change the sequence for contact separation. In particular, it is not not possible with such a device to obtain a simultaneous or delayed separation of vacuum switch contacts with respect to the separation of the switch contacts gas.

Another device of this type is known from patent application EP1109187. allows to adjust the sequence for the separation of the contacts so as to be able to obtain a simultaneous or slightly delayed separation of the vacuum switch contacts by compared to the separation of the gas switch contacts. The mobile contact of the vacuum interrupter is connected to a connecting rod, one end of which is movable in rotation, this end or big end being articulated on a crank pin of a flywheel which can be coupled or uncoupled from a toothed rod controlled in translation by the operating rod of the gas switch.

However, this device has certain drawbacks from a mechanical point of view. First of all, it is necessary to exert sufficient force on the movable contact of the vacuum switch as long as current flow is authorized, so as to have a mutual pressure between the contact surfaces of the contacts of this switch which is greater than a given value to resist electrodynamic forces during the current flow. The steering wheel of the device must therefore be fitted with an elastic system of recall which allows to exert this force required on the movable contact of the vacuum switch. On the other hand, the transmission of the movement of the operating rod of the gas switch to the vacuum interrupter is done by a connecting rod whose axis is oblique to the axis of translation of the movable contact of this vacuum switch. This results in constraints important transverse on the vacuum switch, which can limit its endurance mechanical.

Finally, there is another device of this type described in the patent application. EP1117114, which has in particular compared to the previous device the advantage that the moving contact of the vacuum interrupter is always subjected to directed forces only along the direction of the longitudinal axis of this switch. In addition, elastic means to springs are provided to maintain mutual pressure between the contacts of the vacuum switch as long as this switch is closed. However, the movement of separation of the contacts of the vacuum switch is controlled by the operating rod of the gas switch, which means that the contacts of the vacuum switch should only be separated at the end of opening of the gas switch contacts. It is necessary for this device to have such a delayed contact separation sequence in order to cause the passage zero current before the vacuum interrupter only cuts out. Indeed, the device is used exclusively as a generator circuit breaker, and therefore the gas switch is only present to decrease the percentage of current asymmetry.

Obviously, it is not possible to achieve with this device a separation simultaneous or slightly delayed contacts of the vacuum interrupter compared to the separation of the gas switch contacts.

The invention firstly aims to remedy the drawbacks or limitations of prior techniques, by proposing a hybrid type cut-off device for high or relatively compact and enduring medium voltage which while operating with a single operating member, i.e. with a control mechanism connected to a single operating rod, allows to adjust the separation sequence of the contacts of switches to adequately distribute between the vacuum switch and the gas the transient recovery voltage which appears between the contacts of each switch as soon as they separate. The invention achieves this objective by proposing a switching device operating on the principle of the hybrid type switching device described in European patent application EP1271590A1 published on January 2, 2003. The invention then aims to prevent any bouncing movement of the mobile contact of the vacuum switch during a power interruption by the device, in order to avoid a dielectric reset in this switch.

• une enveloppe remplie d'un gaz diélectrique et ayant un axe longitudinal,
• un interrupteur à vide disposé dans l'enveloppe, comportant une première paire de contacts d'arc constituée d'un premier contact qui est fixe et d'un second contact qui peut être déplacé en translation dans la direction longitudinale de l'enveloppe,
• des moyens prévus pour exercer sur le second contact une force telle que la pression mutuelle entre les surfaces d'appui des premier et second contact soit supérieure à une valeur déterminée tant que l'interrupteur à vide autorise le passage du courant,
• un interrupteur à gaz disposé dans l'enveloppe, comportant une seconde paire de contacts d'arc constituée d'un troisième contact qui est fixe ou quasi fixe et d'un quatrième contact qui peut être déplacé en translation dans la direction axiale longitudinale, une tige de manoeuvre reliée au quatrième contact et pouvant être immobilisée ou déplacée en translation par des moyens de commande,

caractérisé en ce qu'il comprend en outre

• un moyen de raccordement connectant électriquement les second et troisième contacts, apte à être déplacé en translation dans la direction axiale longitudinale solidairement avec le second contact,
• des moyens de déplacement reliés à ce moyen de raccordement et à la tige de manoeuvre pour les déplacer de manière à séparer les second et quatrième contacts respectivement des premier et troisième contacts, comprenant des moyens de liaison à course morte reliant le moyen de raccordement à la tige, ces moyens de liaison permettant de déplacer la tige d'une course morte déterminée tout en agissant sur le moyen de raccordement pour maintenir l'interrupteur à vide fermé pendant ce déplacement, et en ce qu'une fois la course morte parcourue par la tige, ces moyens de liaison à course morte sont aptes à acquérir un mouvement de translation qui est indépendant du mouvement acquis simultanément par le moyen de raccordement.

To this end, the invention relates to a hybrid type breaking device for high or medium voltage, comprising

• an envelope filled with a dielectric gas and having a longitudinal axis,
• a vacuum interrupter placed in the enclosure, comprising a first pair of arcing contacts consisting of a first contact which is fixed and a second contact which can be moved in translation in the longitudinal direction of the enclosure,
• means provided for exerting a force on the second contact such that the mutual pressure between the bearing surfaces of the first and second contact is greater than a determined value as long as the vacuum switch authorizes the passage of current,
• a gas switch arranged in the enclosure, comprising a second pair of arcing contacts consisting of a third contact which is fixed or almost fixed and of a fourth contact which can be moved in translation in the longitudinal axial direction, a operating rod connected to the fourth contact and capable of being immobilized or moved in translation by control means,

characterized in that it further comprises

• a connection means electrically connecting the second and third contacts, capable of being moved in translation in the longitudinal axial direction integrally with the second contact,
• displacement means connected to this connection means and to the operating rod to move them so as to separate the second and fourth contacts respectively from the first and third contacts, comprising dead travel connection means connecting the connection means to the rod, these connecting means making it possible to move the rod by a determined dead stroke while acting on the connection means to keep the vacuum switch closed during this displacement, and in that once the dead stroke is traversed by the rod, these dead-stroke connection means are capable of acquiring a translational movement which is independent of the movement acquired simultaneously by the connection means.

Advantageously, for applications where the device according to the invention is intended to use as a circuit breaker in a high voltage network, the means of movement are arranged so that the separations of the switch contacts vacuum and gas respectively occur simultaneously or slightly offset in time.

Furthermore, a particular embodiment of the invention aims to allow a effective arc blowing in the gas switch, including if the switch device hybrid is intended to support at its terminals a transient recovery voltage with very fast recovery speed as is often the case for applications in high and very high voltage, and in particular when the currents to be cut are lower at around 30% of the breaking capacity of the hybrid device. In this embodiment, in addition to the characteristics of the invention defined above, the hybrid switching device includes an additional pneumatic blowing volume, adjacent to the blowing volume thermal and able to communicate with the latter, delimited by a fixed or mobile bottom which is capable of being brought closer to the volume of thermal blowing to compress the gas dielectric content in the pneumatic blowing volume during an interruption of the current through the cut-off device. The additional pneumatic blowing volume allows to obtain an arc blowing in case the current to be cut is not large enough to generate by thermal effect the necessary overpressure in the blowing volume thermal.

• les moyens de liaison à course morte comprennent des moyens de renvoi de mouvement qui coopèrent avec des premiers moyens élastiques aptes à agir sur le moyen de raccordement pour maintenir l'interrupteur à vide fermé, et comprennent des premiers moyens de butée sur lesquels s'appuient ces premiers moyens élastiques pour exercer une force sur le moyen de raccordement, ces premiers moyens de butée étant aptes à annuler cette force une fois la course morte parcourue,
• les moyens de renvoi de mouvement comprennent deux parties aptes à être déplacées ensemble en appui l'une contre l'autre et à aptes à être dissociées après le commencement de l'ouverture de l'interrupteur à vide,
• les premiers moyens de butée comprennent au moins une tige à course morte qui est solidaire en mouvement d'une première partie des moyens de renvoi de mouvement et qui comporte à une extrémité une tête, et comprennent un premier élément tubulaire d'appui qui est apte à être déplacé dans la direction axiale le long d'un premier élément de support fixe qu'il entoure, ce premier élément tubulaire comportant une partie annulaire qui est traversée par la tige à course morte et contre laquelle la tête de la tige est apte à venir appuyer en butée une fois la course morte parcourue.
• les moyens de déplacement comprennent des second moyens élastiques aptes à séparer les contacts de l'interrupteur à vide dès que la tige a parcouru la course morte et aptes à déplacer le moyen de raccordement et le second contact d'une course d'isolation déterminée par rapport au premier contact lors d'une interruption de courant par le dispositif, cette course d'isolation correspondant à la distance de séparation complète des premier et second contacts,
• les premiers moyens élastiques comprennent un premier ressort qui est disposé en compression entre la partie annulaire du premier élément tubulaire d'appui et la première partie des moyens de renvoi de mouvement,
• les second moyens élastiques comprennent un second ressort qui est disposé en compression entre un second élément de support fixe et une partie annulaire d'un second élément tubulaire d'appui qui entoure ce second élément de support fixe, le second élément tubulaire d'appui étant apte à être déplacé le long du second élément de support fixe dans la direction axiale et étant solidairement relié par au moins un tirant à une partie principale du moyen de raccordement,
• les premier et second éléments tubulaires d'appui sont immobiles en appui l'un contre l'autre tant que la course morte n'a pas été parcourue par ladite tige de manoeuvre lors d'une interruption de courant par le dispositif,
• le second élément de support fixe est muni de second moyens de butée contre lesquels vient buter la partie principale du moyen de raccordement au moment où ce dernier a parcouru la course d'isolation,
• le premier élément de support fixe supporte le troisième contact d'arc et est supporté par le second élément de support fixe grâce à des moyens de fixation disposés selon l'axe longitudinal du dispositif, ce premier élément de support étant maintenu fixe par l'intermédiaire d'un tirant isolant qui est fixé à une extrémité du dispositif.
• une seconde partie des moyens de renvoi de mouvement est solidaire en translation de la tige de manoeuvre.
• une varistance est disposée dans l'enveloppe commune du dispositif de coupure et électriquement reliée en parallèle aux contacts de l'interrupteur à vide afin de pouvoir limiter la tension appliquée sur cet interrupteur, en vue de répartir de façon adéquate la tension appliquée sur les interrupteurs respectivement à vide et à gaz lors de l'ouverture du dispositif de coupure,
• un condensateur est monté en parallèle à l'un des interrupteurs ou en parallèle à chacun des interrupteurs en vue d'obtenir cette répartition adéquate.

According to particular embodiments, a breaking device according to the invention can comprise one or more of the following characteristics taken in isolation or according to all technically possible combinations:

• the dead-stroke connection means comprise movement return means which cooperate with first elastic means capable of acting on the connection means to keep the vacuum switch closed, and comprise first stop means on which are supported these first elastic means for exerting a force on the connection means, these first abutment means being capable of canceling this force once the dead travel has been completed,
• the movement return means comprise two parts able to be moved together by pressing one against the other and able to be separated after the opening of the vacuum switch has started,
• the first abutment means comprise at least one dead-stroke rod which is integral in movement with a first part of the movement return means and which comprises at one end a head, and comprise a first tubular support element which is suitable to be moved in the axial direction along a first fixed support element which it surrounds, this first tubular element comprising an annular part which is crossed by the dead-stroke rod and against which the head of the rod is capable of press the stop once the dead race has been completed.
• the displacement means comprise second elastic means capable of separating the contacts of the vacuum interrupter as soon as the rod has traversed the dead stroke and capable of displacing the connection means and the second contact of an insulation stroke determined by relative to the first contact during a current interruption by the device, this isolation stroke corresponding to the complete separation distance of the first and second contacts,
• the first elastic means comprise a first spring which is arranged in compression between the annular part of the first tubular support element and the first part of the movement return means,
• the second elastic means comprise a second spring which is arranged in compression between a second fixed support element and an annular part of a second tubular support element which surrounds this second fixed support element, the second tubular support element being able to be moved along the second fixed support element in the axial direction and being integrally connected by at least one tie rod to a main part of the connection means,
• the first and second tubular support elements are stationary in abutment against one another as long as the dead travel has not been covered by said operating rod during a current interruption by the device,
• the second fixed support element is provided with second abutment means against which the main part of the connection means abuts when the latter has traversed the insulation stroke,
• the first fixed support element supports the third arcing contact and is supported by the second fixed support element thanks to fixing means arranged along the longitudinal axis of the device, this first support element being kept fixed by means of an insulating tie which is fixed to one end of the device.
• a second part of the movement return means is integral in translation with the operating rod.
• a varistor is placed in the common casing of the cut-off device and electrically connected in parallel to the contacts of the vacuum interrupter so as to be able to limit the voltage applied to this interrupter, in order to distribute the voltage applied to the interrupters adequately vacuum and gas respectively when the cut-off device is opened,
• a capacitor is mounted in parallel with one of the switches or in parallel with each of the switches in order to obtain this adequate distribution.

For applications where the device according to the invention is intended for use as a generator circuit breaker for a medium voltage network, the means of movement are preferably arranged so that the separation of the contacts of the vacuum interrupter occurs significantly delayed compared to separation arcing contacts of the gas switch, so that the current flow through zero is caused by the gas switch before the vacuum switch cuts the power.

The invention, its characteristics and its advantages are specified in the description which follows in relation to the figures below.
Figures 1 to 14, as well as Figure 14 ', correspond to embodiments of hybrid switching devices operating on the principle of the switching device described in European patent application EP1271590A1. However, these embodiments do not incorporate an improvement according to the present invention aimed at preventing any rebounding movement of the movable contact of the vacuum interrupter. Embodiments of such improvements are described in the following with reference to FIGS. 15 to 20.
Figure 1 is a simplified block diagram showing the main elements of a high or medium voltage hybrid switching device in a particular embodiment, shown in the closed position.
FIGS. 2, 3 and 4 represent successive stages in the opening of the hybrid breaking device shown in FIG. 1.
FIG. 5 represents the block diagram of a hybrid switching device identical to that represented in FIG. 1, except that the contacts of the gas switch are arranged so that their separation occurs shortly before that vacuum switch contacts.
FIG. 6 represents an intermediate stage in the opening of the hybrid breaking device shown in FIG. 5.
FIG. 7 is an enlargement of part of the hybrid breaking device shown in FIG. 9.
FIG. 8 is a schematic representation of an embodiment of a hybrid switching device, the simplified diagram of which is shown in FIG. 1.
Figure 9 is a schematic representation of another embodiment of a hybrid switching device in which the contacts of the gas switch are arranged end to end.
Figure 10 is a partial view of the hybrid switching device shown in Figure 9 and whose varistor has been removed.
FIG. 11 represents a subsequent step in the opening of the hybrid cut-off device shown in FIG. 10.
FIG. 12 is a partial schematic representation of an embodiment of a hybrid switching device incorporating an additional pneumatic blowing volume in addition to the thermal blowing volume, in an embodiment for which the blowing volumes are fixed.
Figure 13 is a schematic representation of an embodiment of a hybrid switching device in an embodiment for which the blowing volumes are movable with the operating rod of the device.
FIG. 13a is an enlargement of part of the hybrid cut-off device shown in FIG. 13.
FIG. 14 represents an intermediate stage in the opening of the hybrid cut-off device shown in FIG. 13, corresponding approximately to the instant when the contacts of the gas switch separate.
FIG. 14 'is a schematic representation of an embodiment of a hybrid breaking device in which the first elastic means comprise two springs arranged on either side of the movement return means.
FIG. 15 is a schematic representation of an embodiment of a hybrid breaking device according to the invention, which is functionally equivalent to the device shown in FIG. 12 and which includes an improvement making it possible to prevent any rebound of the movable contact of the vacuum switch.
FIG. 16 represents the same hybrid breaking device as that of FIG. 15, at the end of opening of the contacts of the gas switch.
FIG. 17 is a schematic representation of an embodiment of a hybrid switching device according to the invention, which is functionally equivalent to the device shown in FIG. 13 and which includes an improvement making it possible to prevent any rebound of the movable contact of the vacuum switch.
FIG. 18 shows the same hybrid breaking device as that of FIG. 17, at the end of opening of the contacts of the gas switch.
FIG. 19 is a schematic representation of another embodiment of a hybrid switching device according to the invention, in an embodiment for which the contacts of the gas switch are arranged end to end.
FIG. 20 is a schematic representation of another embodiment of a hybrid breaking device according to the invention, in an embodiment for which the device is intended for use as a generator circuit breaker.

Figure 1, the hybrid switching device 5 shown is generally symmetrical of revolution around an axis A. It includes a vacuum switch 10 containing a first pair of arcing contacts 1 and 2. A first contact 1 is fixed and is connected in permanently at a crossing 7 at the end of the device 5. A second contact 2 is movable in the axial direction A. The device also includes a gas switch 11 connected electrically in series with the vacuum switch. This gas switch includes a second pair of arcing contacts, consisting of a third and a fourth contact 3 and 4. The third contact 3 is fixed in the casing 12 by means of holding means shown in Figures 8 and 9. The fourth contact 4 is movable in the axial direction A and secured to an operating rod 6 connected to the control mechanism 8 of the device 5. The two switches 10 and 11 are arranged in a common envelope 12 filled of a dielectric gas.

In the embodiment shown, the movable contact 4 is introduced into the contact 3 fixed over a certain overlap distance when the cut-off device is closed. By this overlap, the separation of the third and fourth contacts takes place at a instant when the operating rod 6 has traversed a determined distance known as setting speed, which is to say that the overlap distance corresponds to the distance of speed setting traversed by the rod 6. This speed setting is applied to the movable contact 4 of the gas switch and allows this contact 4 to be separated from the fixed contact 3 with a relatively high speed from the start of separation. A few milliseconds after said separation, this speed can reach a sufficient value favoring the extinction of the electric arc created between the switch contacts. It is particularly useful for cut the so-called capacitive currents without arcing.

The contact 2 is integral in translation with a mobile connection means 13 which permanently electrically connects it to the fixed contact 3. Arranging the third contact so that it remains fixed in the breaking device allows the separation of contacts 3 and 4 in the gas switch does not depend on mechanical operation of the assembly carrying the second movable contact of the vacuum switch.

Movement return means 15 can be separated into two parts 16 and 17. These two parts are in abutment against each other in the axial direction A by through coupling means 22 provided at their two opposite ends. The second part 17 is integral in translation with the rod 6, and the first part 16 can be moved in translation by a determined stroke D in the axial direction A relative to the connection means 13. In the embodiment shown, this stroke D is equal to the overlap distance of contacts 3 and 4, which means that it is equal to the speed-up distance defined previously.

These return means 15 can also be produced by a telescopic connection not shown comprising two parts which can be locked in abutment one against the other and sliding one inside the other during their separation in the axial direction, one such telescopic connection being functionally equivalent to the return means 15 shown schematically in Figure 1. However, such an embodiment may have drawbacks due to the increase in moving masses.

First elastic means are provided to maintain the vacuum switch closed, by exerting on the connection means 13 and therefore on the contact 2 a first thrust which remains above a determined threshold until an instant when the rod 6 has traversed the determined stroke D.

At this instant corresponding to the representation of FIG. 2, the contacts of the gas switch will separate. This first push ceases to act on the means of connection at said instant, to let act on contact 2 of the second elastic means who exert a second thrust in the opposite direction. This second push highlights movement contact 2, which causes the separation of the contacts of the vacuum interrupter. This separation thus occurs simultaneously or delayed with respect to the separation gas switch contacts, according to a determined sequence.

In the device described, the first and second elastic means provided for exerting said first and second thrusts comprise respectively a first spring 20 and a second spring 21 both of which are armed in compression and associated respectively with first and second stop means 14 and 19. The first spring 20 is mounted between the connection means 13 and the first part 16, to exert respectively on these elements opposite thrusts - F ₂₀ and F ₂₀ . The closed position of the cut-off device 5 is ensured by locking the movement of the rod 6 by the control mechanism 8, which makes it possible to keep the two parts 16 and 17 immobile in abutment against one another and also to maintain a certain pressure on the contacts 1 and 2 thanks to the first spring 20 associated with the connection means 13. This contact pressure allows the switch to ensure the passage of a fault current, and depends on the value of the current defect to bear.

In the event of a power interruption order sent to the control mechanism 8 of the cut-off device 5, the rod 6 must be released to allow the first part 16 to move in translation relative to the means 13 under the effect of the relaxation of the first spring 20. This relative movement is then stopped as soon as the first part 16 has traveled the race D, by the first stop means 14 which form one end of the means of connection 13 so that this part 16 is made integral in translation with said medium 13 as shown in Figure 2.

The return means 15 and the first elastic means form a set of link which connects the connection means 13 to the rod 6. This assembly can be qualified as dead-stroke connection means, in the sense that these connection means do not allow by means of connection to follow the movement of the rod as long as it has not traveled a specific race. During this race D, the 1st connection means 13 remains stationary since the return means 15 do not transmit the movement of rod 6. This property is verified both at the opening and at the closing of the device. cut.

The movement of contact 2 during the separation of contacts 1 and 2 of the switch vacuum 10 is provided by the second semi-mobile spring 21, one end of which is stationary because in permanent support against the face of the vacuum switch which is crossed by the rod carrying the contact 2. The other end of this spring 21 is movable, in permanent support against the connecting means 13, and exerts against the latter a thrust which remains very lower than that of the first spring 20.

The dead-stroke connecting means cooperate with the second elastic means to move the rod 6 and the connection means 13 so as to separate the contacts movable 2 and 4 respectively fixed contacts 1 and 3. In the embodiment shown, they are a constituent part of the means of movement which allow the separations contacts 1 and 2 and contacts 3 and 4 of the vacuum and gas switches respectively occur simultaneously or slightly over time.

The second stop means 19 are arranged so as to stop the translational movement of the connection means 13, as soon as the latter has traveled a certain stroke d ₁ as shown in FIG. 3. These stop means 19 are electrically and mechanically connected to the fixed contact 3, and advantageously participate in the electrical connection between the contacts 2 and 3. Here they consist of a cylindrical stud of axis A, which is introduced into a hollow tubular part of the mobile connection means 13 which can thus slide in the axial direction A. They are also electrically and mechanically connected to a conduction element 9 which surrounds and maintains a blowing chamber arranged in the axial direction A. In a known manner, this chamber comprises a thermal blowing volume 11A and a blowing nozzle 11B. The blowing nozzle 11B is intended to blow an electric arc between the contacts of the gas switch by thermal expansion of the dielectric gas contained in this blowing volume 11A.

The conduction element 9 acts as the main contact for the passage of the continuous current when the cut-off device 5 is closed. The electrical connection between element 9 and an outlet 33 is provided by means of a sliding contact 17A supported by the second part 17 of the return means 15 at the level of the means of coupling 22. This second part 17 is electrically conductive and moves in translation with the rod 6 while remaining in electrical contact by a sliding contact 28 with a fixed conductive tube 31 connected to the socket 33. The first part 16 of the means reference 15 is electrically insulating for reasons explained below.

The connection means 13 in the illustrated embodiment consists of of a metal sleeve with symmetry of revolution in the axial direction A. The different parts constituting this part are referenced in Figure 2. The socket has a part hollow tubular 13A which has at its open end a first annular shoulder which constitutes the first abutment means 14. This hollow part 13A has a bottom 13C intended to bear against the cylindrical stud constituting the second means of stop 19. The socket also has a cylindrical part 13B in which is formed an annular housing 13D open towards the vacuum switch 10 and intended to accommodate the second spring 21. The wall 13E which surrounds this housing 13D has at its end a second annular shoulder 13F to hold the first spring 20 in abutment. Spring 20 is permanently compressed between this shoulder 13F and an annular wall 16A which constitutes one end of the first part 16. The internal diameter of this wall 16A is substantially equal to the outside diameter of the tubular part 13A of the sleeve 13, of so that the part 16 can slide along the sleeve in the axial direction A.

Following the release of the rod 6, the first part 16 of the return means 15 is moves in translation from the position shown in Figure 1 to that of Figure 2. It pushed in its movement the second part 17, and the sliding contact 17A is provided to separate from the conduction element 9 so that the fault current flows exclusively by arcing contacts 3 and 4 in the gas switch 11. As mentioned previously, the first part 16 is electrically insulating or at least allows electrically isolate between them the connection means 13 and the second part 17 which is conductive. Indeed, if this part 16 was fully conductive, there would be appearance of electric arcs between parts 16 and 17 after the sliding contact 17A is disconnected from the conduction element 9.

The translational movement of the return means 15 is transmitted to the rod 6, and consequently at the movable contact 4 of the gas switch. The thrust provided by the relaxation of the first spring 20 makes it possible to assist the control mechanism 8 for the rod operation.

Figure 2, the device is shown when the annular wall 16A of the first part 16 abuts against the first abutment means 14, after having traveled the distance D. The movable contact 4 has simultaneously traveled the distance D in the gas switch, and is about to be separated from the fixed contact 3. At this stage, the push - F ₂₀ of the first spring 20 can no longer act effectively on the connection means 13 to maintain the pressure on the contact 2, and the thrust of the second spring 21 is free to act on this means 13 for its translation. The movable contact 2 in the vacuum switch 10 is then about to be separated from the fixed contact 1, simultaneously with the separation of the contacts 3 and 4 in the gas switch.

Between the positions shown in Figures 2 and 3, the connection means 13 is set in motion by the relaxation of the second spring 21 which permanently exerts on this means 13 a thrust F ₂₁ represented in FIG. 3. This setting in motion causes on the one hand the displacement of the second contact 2 to open the vacuum switch 10, on the other hand the continuation of the movement in translation of the return means 15.

Figure 3, The movement of contact 2 is intended to be stopped as soon as the latter is completely separated from contact 1 in the vacuum switch 10. The complete separation is carried out when the movable contact 2 is separated from the fixed contact 1 of a insulation distance determined in a vacuum, for example of the order of 15 mm. To this end, the movement of the connection means 13 is stopped by the second stop means 19 which are arranged so that the stroke d ₁ traveled by this means 13 is equal to the insulation distance corresponding to complete separation of contacts 1 and 2. In what follows, this stroke d ₁ is also called insulation stroke.

The thrust F ₂₁ of the second spring 21 is provided sufficient to initially supply the energy necessary for the displacement of the contact 2 and of the parts 13 and 16 integral in translation, and in the second time to maintain the contacts 1 and 2 open as shown in the figure 3. However, this thrust remains much lower in standard than that F ₂₀ of the first spring 20. In fact, as long as the vacuum switch 10 remains closed as shown in FIGS. 1 and 2, the pressure to be maintained on the contacts 1 and 2 is quite high, for example of the order of 2000 N for a fault current of 40 kA. The thrusts F ₂₀ and F ₂₁ of the first and second springs are therefore provided to present a difference ΔF = F ₂₀ -F ₂₁ which remains greater than a determined threshold S. F ₂₀ decreases between the times corresponding to Figures 1 and 2 while F ₂₁ is stable at its maximum, F ₂₀ remaining high enough to satisfy the condition F ₂₀ > F ₂₁ + S.

In a particular mode of arrangement of the control mechanism 8 of the rod 6 which actuates the opening of the switches, said rod is driven in translation by the mechanism 8 with a speed greater than that acquired by the connection means 13 under the effect of the relaxation of the second spring 21. The device shown in Figures 1 to 4 operates according to this arrangement mode. Parts 16 and 17 of the return means 15 are in this case provided to separate before the means 13 comes into abutment, that is to say before contacts 1 and 2 are completely separated at the instant corresponding to the figure 3. For example, the separation of parts 16 and 17 can be planned to start just after that of contacts 1 and 2, i.e. just after the instant corresponding to the Figure 2. Thus, only a first phase of the translational movement of contact 2 is transmitted to the rod 6 by the return means 15. After this first phase which can be very short, the return means 15 therefore no longer exert any action on the rod 6 to help its translational movement, which is then entirely ensured by the mechanism of control 8. This operation makes it possible to have a higher speed of the mobile contact 4 when the arc is blown between the contacts 3 and 4 in the gas switch 11.

Contacts 1 and 2 are kept open in the vacuum switch 10, until the contacts 3 and 4 are fully opened in the gas switch as shown in Figure 4 where these contacts are separated by some insulation distance d ₂ at the end of travel of the movable contact 4. This distance d ₂ is much greater than the insulation stroke d ₁ mentioned for the vacuum interrupter, since d ₂ is generally between 80 and 200 mm for most blow gas switches.

Figure 5 shows the block diagram of a device identical to that shown in Figure 1, except that the contacts of the gas switch are arranged to that their separation occurs shortly before that of the switch contacts at empty. To obtain such early separation of the contacts of the gas switch, it suffices that the overlap distance of these contacts is somewhat less than the stroke D defined above, when the cut-off device is closed. So we have a distance of overlap, in other words a speed-up distance for the rod 6, equal to D-ε with the distance ε which is a function of the time shift desired for this separation anticipated.

Figure 6, at the moment when the rod 6 has traveled the determined stroke D, the contacts of the gas switch has just been separated and is moved away from the distance ε. So we see that this distance ε is defined as the desired spacing for the contacts of the switch at gases when those of the vacuum interrupter are about to be separated.

Figure 7 is an enlarged partial view of the hybrid switchgear shown in Figure 9, in the closed position. This view shows a second mode of realization of a breaking device, in which the contacts 3 and 4 of the gas switch 11 are held in abutment against each other with a certain assured contact pressure by elastic means to resist electrodynamic forces during passage current.

Delay means 18 for setting the moving contact 4 in motion are inserted between this contact and the device operating rod 6, so that the separation of contacts 3 and 4 caused by said setting in motion of contact 4 takes place precisely at the moment when the rod 6 has traversed the defined speed-up distance previously.

The rod 6 and the contacts 3 and 4 are preferably of tubular shape in the axial direction A, and the contacts 3 and 4 advantageously each have their end a tip respectively 3A and 4A made of a conductive material refractory. The arcing contact 4 also has orifices or openings 4B to allow the evacuation of hot gases which are in overpressure inside the tubular structure of said contact during the breaking of a fault current by the arcing contacts 3 and 4. The overpressure gases are discharged into the space between the delay means 18 and the second part 17, then pass into the space between the rod 6 and the tube conductor 31 by openings made for this purpose in the second part 17. Finally, these gases undergo a final expansion when passing through the volume adjacent to the interior wall of the casing 12 by openings made for this purpose in the conductive tube 31. Good heard, other arrangements of openings for the evacuation of gases in overpressure can be expected.

• un premier élément tubulaire 25 disposé dans le prolongement axial du contact 4, solidairement raccordé à ce dernier et pouvant coulisser à l'intérieur de la tige 6 lors du déplacement de celle-ci, la distance de mise en vitesse pour la tige 6 étant définie par la course autorisée pour ce coulissement,
• des troisièmes moyens de butée 23 fixés à une extrémité de l'élément tubulaire 25 au niveau du raccordement avec le contact 4,
• un second élément tubulaire 26 solidairement relié par une extrémité à la seconde partie 17 des moyens de renvoi 15, de diamètre supérieur à celui de l'élément tubulaire 25, pouvant coulisser le long des troisièmes moyens de butée 23 dans la direction axiale A lors du déplacement de la tige 6 et comportant à son autre extrémité un chapeau annulaire 27 destiné à venir en appui contre les moyens de butée 23,
• un troisième ressort 24 à spires disposé selon la direction axiale A, intercalé entre les premier et second éléments tubulaires, en appui d'un côté contre les troisièmes moyens de butée 23 et d'un autre côté contre la seconde partie 17 des moyens de renvoi 15.

The delay means 18 include:

• a first tubular element 25 disposed in the axial extension of the contact 4, integrally connected to the latter and capable of sliding inside the rod 6 during the displacement of the latter, the speed-up distance for the rod 6 being defined by the stroke authorized for this sliding,
• third abutment means 23 fixed to one end of the tubular element 25 at the connection with the contact 4,
• a second tubular element 26 integrally connected at one end to the second part 17 of the return means 15, of diameter greater than that of the tubular element 25, which can slide along the third stop means 23 in the axial direction A during the displacement of the rod 6 and comprising at its other end an annular cap 27 intended to come into abutment against the stop means 23,
• a third spring 24 with turns arranged in the axial direction A, interposed between the first and second tubular elements, bearing on one side against the third stop means 23 and on the other side against the second part 17 of the return means 15.

In the embodiment shown, the delay means 18 are dimensioned so that the start-up distance is equal to the stroke D that the return means 15 relative to the connection means 13, so as to obtain the simultaneous separation of the two pairs of contacts.

When the device cuts power, once the sliding contact 17A is disconnected from the conduction element 9 and before the instant of separation of the contacts 3 and 4, the fault current flows from the fixed contact 3 to the conductive tube 31 passing through the contact 4, the tubular element 25, sliding contacts 29, a portion of the second part 17 return means 15, and finally the sliding contacts 28.

During the common translational movement of parts 16 and 17 of the means of return 15, the movable contact 4 is held in abutment against the fixed contact 3 with a certain contact pressure thanks to the thrust exerted by the third spring 24. When the start-up distance has been traveled by the rod 6, the annular cap 27 arrives bearing against the stop means 23. The spring 24 no longer exerts any action on the contact 4 which is therefore driven in translation with the rod 6 and the second part 17. Thus, the movable contact 4 is integral in translation with parts 6 and 17 only from an instant given from the moment the device is triggered.

Similarly to the device shown in Figure 1, the operation of the device is here provided for obtaining the separation of the contacts 3 and 4 in the switch gas simultaneously with that of contacts 1 and 2 in the vacuum interrupter. It is however possible to have an early separation of the contacts of the gas switch, by arranging the elements of the device so that the speed-up distance is less than the distance D, similar to the arrangement shown in Figure 5.

Figure 8 shows schematically an embodiment of a device for hybrid shutdown, the simplified block diagram of which is shown in Figure 1. The gas switch contacts are pushed into each other with a certain distance cover when the cut-off device is closed, as in Figure 1.

The volume adjacent to the interior wall of the envelope common to both switches is dimensioned to accommodate a varistor 32 electrically connected in parallel to the vacuum switch contacts in order to limit the applied voltage on said switch. This allows to adequately distribute the voltage applied to the vacuum and gas switches respectively when the cut-off device is opened. The voltage distribution can also be adjusted using at least one capacitor mounted parallel to the cut-off device or parallel to one of the two switches.

In the case of an air-insulating device as shown where the devices switchgear can be housed in a vertical insulating jacket, it can be advantageous to have the vacuum switch in the most distant part of the enclosure of the ground. This makes it possible to obtain a distribution of natural tension which gives a tension on the gas cut-off device higher than that applied to the vacuum switch. Through elsewhere, the relative compactness of hybrid devices such as those represented in the present may allow the use of an existing insulating envelope intended for a non-hybrid gas switch.

The electrical connection between the varistor 32 and the movable contact of the switch vacuum is ensured via the metal sealing bellows of this switch. The electrical connection between the connection means 13 and the conductive pad forming the second stop means 19 is provided by sliding contacts. Ports or openings are provided at the connection between this stud and the conduction element 9 which surrounds the blowing chamber of the gas switch, to allow evacuation hot gases as explained in the commentary to figure 7. Such openings are also provided in the first and second parts 16 and 17 of the return means 15, as well as in the conductive tube in which this second part can slide.

Electrically insulating tie rods 30 participate in the mechanical maintenance of the gas switch in the enclosure of the switching device. These tie rods are fixed by a end on the face of the vacuum switch which is crossed by the rod carrying the contact mobile. They are rigidly connected by their other end to the conduction element 9 and thus keep the third contact fixed in the gas switch.

The device operating rod 6 is rigidly linked to the movable contact 4 thus than in the second part 17 of the return means 15. The three elements 6, 4 and 17 are therefore permanently united in translation in this embodiment.

Figure 9 is a schematic representation of another embodiment of a hybrid shut-off device in the closed position, in which the switch contacts gas are arranged end to end. Many elements are identical to those used for the embodiment shown in Figure 8. However, the different structure of gas switch contacts implies that the driving of the moving contact of this switch can not be performed as directly as for the embodiment where these contacts are fitted. In order to respect the desired opening sequence of switches, delay means 18 as detailed in FIG. 7 are provided to delay the setting in motion of said movable contact. These means allow the rod 6 to cover the start-up distance as explained above, and allow therefore the movable contact 4 to be driven by the rod 6 with a high speed at separation of the vacuum switch contacts begins, as well as in the embodiment with plug contacts.

Figure 10, the elements of the hybrid switching device shown are identical to those of figure 9, except for the varistor which was removed and the envelope insulator whose diameter has been reduced accordingly.

Figure 11 shows the device of Figure 10 at a time corresponding to the step in Figure 2.

The devices described above in Figures 1 to 11 do not however allow to obtain an arc blowing which is effective in all circumstances in the switch gas. In particular, in the case where the current to be cut is not large enough to generate a sufficient thermal effect to obtain the necessary overpressure in the volume of thermal blowing, the addition of an additional pneumatic blowing volume can provide sufficient overpressure for effective arc blowing, such as known for conventional high voltage circuit breakers. It should be noted that in a hybrid cut-off device, the need for blowing is lower than in a device conventional cut-off because the vacuum switch contributes to the withstand voltage recovery.

Figure 12, a high-voltage hybrid switching device incorporates a volume 11C additional pneumatic blower in addition to the blowing volume 11A thermal, in an embodiment for which this thermal blowing volume is motionless. Many parts of the device are common to the device shown in Figure 9, and in particular the contacts of the gas switch are arranged butt in closed position. The main modifications to be made to the figure 9 for the addition of the additional pneumatic blowing volume relate to the conductive wall 9 ′ which forms the bottom of the thermal blowing volume 11A as well as on the first part 16 of the movement return means of the device.

In what follows, the blowing volume is also called the compression volume. booster tire, since assistance with thermal blowing results from compression of the gas in this additional volume.

As known from the prior art, the volume of thermal blowing and the compression volume can communicate by valves, for example ball. This allows the passage of gases from the compression volume to the blowing volume thermal first during a first phase of compression, and then during the final phase of compression in case the overpressure generated by the thermal effect alone is insufficient for blowing the arc. This insufficiency is then compensated by a supply of compressed gas to the thermal blowing volume. Conversely, in the case where the overpressure generated by the thermal effect alone in volume 11A is sufficient and greater than the overpressure obtained by pneumatic compression in volume 11C, it it is advantageous not to let the gas escape from volume 11A towards volume 11C so not to reduce the effect of thermal blowing. In addition, in an implementation of a hybrid switching device as shown in figure 12, and in case of strong currents to be cut, it is necessary to prevent the overpressure in the volume of 11C compression could reach excessive values which would tend to slow down or block the action of the second spring 21 to open the contacts of the vacuum switch. In this Indeed, valves 35 are provided in the wall 9 'of the volume 11A to ensure the desired functions of unidirectional gas passage or isolation of the two volumes of blowing depending on the breaking of the weak or strong currents respectively.

On the other hand, at the end of a closing operation of the cut-off device hybrid, it is necessary not to create a depression in the blowing volume pneumatic 11C, this in order to be able to correctly ensure the compression of the gas if the device should open again. For this purpose, it is advantageous to provide at least one valve 36 for example ball in the bottom of the compression volume, this bottom being formed by an annular wall 16A which constitutes one end of the first part 16 of the movement return means of the device.

Finally, the compression volume 11C must be tight with respect to the gas of the envelope of the device during compression, so that the dielectric gas under pressure is channeled only to the gas switch contacts for blowing. To seal this volume, it is possible to increase the diameter of the wall annular 9 'of volume 11A relative to the embodiment of the device of FIG. 9 in order to make a sealed contact area 37 between this annular wall 9 'and the interior wall cylindrical of the first part 16 of the return means.

The compression volume 11C can be seen as the sum of two adjacent partial volumes Vc ₁ and Vc ₂ . The length of the volume Vc ₁ in the longitudinal direction corresponds to the stroke D mentioned on the block diagram of FIG. 1, which means that the compression volume 11C will be reduced to the volume Vc ₂ when the first part 16 of the return means will have traversed this race D at an instant which will correspond to the beginning of the separation of the contacts of the gas switch. Then, the volume 11C will continue to be compressed during the opening of the contacts of the vacuum switch under the action of the second spring 21, since the first part 16 of the return means will then be integral in movement with the movable contact of the vacuum switch and will continue to approach the annular wall 9 '.

In the previous embodiment for which the thermal blowing volume is stationary in the cut-off device, the compression stroke in the pneumatic blowing volume is at most equal to the sum of the distances D and d ₁ defined above. Thus, the compression volume is necessarily limited in the longitudinal direction. To obtain a significant additional pneumatic blowing, it is then necessary to increase the radial dimensions of the compression volume, and therefore in particular to increase the diameters of the annular walls 9 'and 16A which delimit this volume. This results in an increase in the radial size of the breaking device.

For medium voltage applications (less than 72.5kV) and in particular those where the insulation between the breaking chamber and the external environment is achieved by a metal casing, it is generally possible to have the radial size necessary for the device. On the other hand, such a radial size can pose problems. for applications where the isolation of the switching chamber is achieved by an enclosure porcelain.

Figure 13, a particular embodiment of a hybrid blow-off device tire is shown schematically. This embodiment differs significantly precedents of the fact that the thermal blowing volumes 40A and pneumatic 40C of the gas switch 40 are movable with the operating rod 6 of the device.

The hybrid switching device is shown in the closed position. The contacts of the vacuum switch 10 is pressed against each other, and the contacts of the switch gases are fitted into each other. The device has a number of similarities to that shown in Figure 8. In particular, the vacuum switch 10, the connection means 13, as well as the first and second elastic means can be identical in the two realizations.

Figure 13a, part of the device of Figure 19 centered on the gas switch 40 is shown in enlargement. As with the device in FIG. 8, the movement return means 15 comprise two parts 16 and 17 which are suitable for be moved together in abutment against one another and able to be separated after the beginning of the opening of the vacuum switch. The second part 17 is united in translation with the operating rod 6, because this part 17 is fixed to the periphery an approximately 40D cylindrical tubular wall which separates the two blowing volumes 40A and 40C and the gas contained in the envelope of the device. This wall 40D is in fact fixedly connected to the operating rod by means of a annular wall 39 which separates the two blowing volumes.

The thermal blowing volume 40A is delimited at one end by a nozzle blowing 40B fixed to one end of the wall 40D, this nozzle thus being integral with it translation with the operating rod 6. A permanent current contact 44 surrounds the end of the wall 40D and participates in the longitudinal holding of the nozzle against the wall, this contact therefore being movable with the rod and the nozzle. The 40D wall is conductive and allows the passage of permanent current from contact 44 to a conductive element tubular 45 which is fixed and is electrically connected to an outlet 33 of the device cut-off, this wall 40D being able to slide in leaktight fashion along the element tubular conductor 45 while remaining electrically in contact with the latter. The movable permanent current contact 44 has a tubular portion which is introduced in a fixed permanent current contact 43, which is tubular in shape and is electrically connected to connection means 13. The overlap distance of permanent current contacts 43 and 44 is of course provided less than the distance from covering D of the arcing contacts 3 and 4 of the gas switch 40, so that these contacts continuous current can be separated before the arcing contacts are separated at their turn during a power outage, as shown in Figure 14.

The fixed conductive element 45 maintains a sealing element 41 which has a fixed piston function for the compression volume 40C, and which is capable of isolating this compression volume of the adjacent volume 42 delimited by the rod 6 and the tubular element 45. This sealing element 41 is here provided with a valve 41A intended to allow passage dielectric gas from volume 42 to compression volume 40C during a reclosing operation of the hybrid switching device, thus avoiding creating a depression in this volume.

The annular wall 39 which separates the two blowing volumes 40A and 40C has openings 38 intended to allow the passage of compressed gases from the volume of compression 40C to the thermal blowing volume 40A. In the realization shown in the figure, these openings 38 are simple passages not fitted with valves, which is satisfactory in a number of applications. For example, this realization is effective when the blowing which is carried out by pneumatic compression to cut small currents with short arc times only needs one relatively small blowing complement by thermal effect when cutting the main currents.

As a variant not shown in the figure, the openings 38 may also include valves, as known from the prior art and in particular from patent FR2751782. In in addition, the sealing element 41 may be provided with a valve intended to limit the overpressure. in the compression volume by allowing the passage of overpressure gases to the volume 42.

Figure 14, the hybrid switching device of Figures 13 and 13a is shown in a intermediate stage of its opening, corresponding approximately to the moment when the contacts 3 and 4 of the gas switch separate i.e. when the moving contact 4 which is integral in movement with the operating rod has traveled the overlap distance D. At this instant, the annular wall 39 which separates the two blowing volumes has moved the same distance D to the fixed piston of the compression volume 40C, which allows compressed dielectric gas to pass into the thermal blowing volume as shown by an arrow in the figure.

Thus, after the separation of the arcing contacts of the gas switch, the blowing of the arc is partly effected by pneumatic compression. We can note that this compression is carried out during the entire stroke of the operating rod, at the difference from previous embodiments where the thermal blowing volume is stationary in the device. A hybrid shut-off device that has a blowing volume mobile thermal therefore has the advantage of being able to cut currents with durations arc in principle longer compared to a thermal volume device stationary as shown in Figure 12. Furthermore, the longitudinal dimension of the compression volume 40C is not limited by the dead travel D as previously, which allows to obtain a satisfactory compression volume without having to increase the radial dimension of this volume. Mobile thermal volume devices are therefore well suited for applications where the isolation of the switching chamber is achieved by a porcelain shell, and in general for higher high voltage applications at around 100kV.

In Figure 14 ', a hybrid switching device is shown in an embodiment close to that shown in Figure 14 while being relatively more complex. Indeed, although most of the elements of this device are common with the previous device, some modifications and additional elements have been made. In particular, the first elastic means comprise, in addition to the first spring 20, another spring 42, these two springs being arranged on either side of the movement return means 15 '. The spring 42 is interposed between the second part 17 'of the movement return means 15' and the tubular envelope of the compression volume 40C. The two springs 20 and 42 cooperate so that the operating rod 6 can be displaced from the dead stroke D while maintaining a certain pressure between the contacts of the vacuum interrupter. However, only the first spring 20 performs the function of maintaining this pressure, owing to the fact that a fixed tie rod 46 provided with an end stop allows the second part 17 ′ to be blocked in translation to prevent the force F ₄₂ applied by the spring 42 is not added to the force F ₂₀ applied by the first spring 20.

The stroke D1 that the first part 16 of the movement return means 15 ′ can travel under the action of the first spring 20 is considerably reduced compared to the previous embodiments. Thus, the force F ₂₀ applied by this spring varies less during an opening or closing operation of the hybrid cut-off device, which makes it possible to limit the forces applied to the vacuum switch during opening and closing of his contacts. The first elastic means being intended to allow the displacement of the operating rod 6 of a dead stroke D, it is necessary that the spring 42 can drive the rod over a certain stroke less than or equal to the distance D2 shown in the figure, before the first spring 20 causes this rod on the race D1 by means of movement return means 15 '. The sum of the two strokes D1 and D2 must be equal to the dead stroke D if simultaneous separation of the contacts of the gas and vacuum switches is desired. In addition, it is necessary that the force F ₄₂ be greater than the force F ₂₀ at least in the closed position shown, in order to allow the first part 16 of the movement return means 15 'to have traveled only the distance D1 after the second part 17 ′ of the movement return means 15 ′ is made integral in movement with the operating rod. It is possible to arrange the device of this figure 14 ′ to have a distance D1 relatively small compared to the distance D2 , which limits the travel of the first part 16 of the movement return means 15 '. This provides a relatively limited rebound of this part 16 when it comes into abutment against the shoulder 14 which is integral with the connection means 13, and thus makes it possible to limit the risk of dielectric re-ignition in the vacuum switch. However, even with this solution, it is difficult to completely avoid a rebound of the part 16, and it may prove useful to modify the device to make an improvement according to the present invention as presented in the description with reference to Figures 17 and 18. In particular, it is possible to replace the first part 16 as well as in particular the parts situated to its left in FIG. 14 'by a part of the device of FIG. 17. Indeed, in FIG. 17, the part of the device located to the left of part 16 is arranged to prevent a rebound of the movable contact of the vacuum switch when this part 16 has traveled its dead travel D.

Figure 15, an embodiment of a hybrid switching device according to the invention is shown diagrammatically. This achievement is functionally equivalent to the device shown in FIG. 12, due to the fact that the blowing volumes thermal 11A and pneumatic 11C respectively are fixed. It involves in relation to the device of FIG. 12 an improvement which makes it possible to prevent any movement from rebound of the movable contact of the vacuum switch, in order to avoid re-priming dielectric in this switch.

As in the device shown in FIG. 12, means of connection to dead travel are arranged to allow movement of the rod 6 which carries the contact movable 4 of the gas switch, while the vacuum switch is kept closed for this displacement corresponding to a dead stroke D. They notably include movement return means 15 which cooperate with a first spring 20 capable of acting on a connection means to keep the vacuum switch closed. But at the Unlike the device of FIG. 12, the dead-stroke connection means are here suitable to acquire a translational movement which is independent of the acquired movement simultaneously by the connection means 13 '.

Indeed, in the embodiments of hybrid switching devices as shown Figures 8 to 14 and 14 ', the first part 16 of the movement return means becomes integral in movement with the connection means 13 once the dead travel D or D1 traversed by this part 16. These achievements are not completely satisfactory because at the end of the dead race, part 16 can bounce against the first stop means 14 which are integral with the connection means 13, thus causing a rebound of this piece 13. Since the connection means 13 is necessarily integral in movement with the movable contact of the vacuum interrupter, the rebound of part 13 implies a similar rebound of this movable contact with respect to the fixed contact. This is not acceptable because the distance between the contacts of the vacuum interrupter is then significantly reduced in the phase corresponding to the start of the separation process of these contacts, which is likely to cause a dielectric reset in this switch.

As can be seen in FIG. 15, the dead-stroke connection means comprise first abutment means 14 'on which the first spring 20 rests to exert a force on the connection means 13 '. These first stop means 14 ' comprise at least one rod 14'A which is integral in movement with the first part 16 of the movement return means 15 and which comprises at one end a head 14'B. A single rod 14'A is shown in the figure for the sake of clarity, but it is understood that several similar rods can be fixed to the first part 16, for example arranged equidistant from each other along a circle centered on the longitudinal axis A of the device. Each rod then has the same length as the single rod shown, and comprises at one end a similar head 14'B. In an equivalent embodiment, a 14'A rod can also be made up of an angular portion of a tubular element whose axis coincides with axis A of the device, and a head 14′B could then have the shape of an angular portion of an annular element centered on this axis A.

The first abutment means 14 ′ further comprise a first element tubular support 14'C which is able to be moved in the longitudinal axial direction A along a fixed support element 50 which it surrounds. In the embodiment shown on the figure, the fixed support element 50 consists of a first part 50A which carries the fixed arcing contact 3 of the gas switch and of a second part 50B which is maintained fixed by means of an insulating tie rod 30 'fixed to one end of the device. The second part 50B keeps the first part 50A in place by means of fixing means 51 arranged along the axis A of the device, and is thus electrically in contact with this last.

The first tubular support element 14'C has an annular part which is crossed by the rod (s) 14'A, so that each rod 14'A is capable of sliding at through this 14'C element. Each head 14'B of a rod is capable of coming to bear in abutment against this annular part once the dead race D traveled by each rod in solidarity with the first part 16.

The first spring 20 is arranged in compression between the annular part of the first tubular element 14'C and the first part 16 of the return means of movement 15. During the relaxation of the spring 20 which causes the course of the race dead D, the first tubular element 14'C remains in abutment against the connection means 13 'which is integral in movement with the movable contact of the vacuum switch, which allows keep the vacuum switch closed. Once the dead race D has been covered by the movement return means 15 as well as by the rod (s) 14'A, the rebound of the spring 20 is abruptly interrupted because each head 14′B of a rod abuts against the first tubular support element 14'C, this state being designated as the setting stop of the first stop means 14 'in the following. The first tubular element 14'C support then becomes integral in movement with the first part 16 of the means movement return 15, and therefore the first stop means 14 'cease to exercise any force on the connection means 13 ', thus authorizing the setting in motion of the movable contact of the vacuum switch under the action of a second spring 21. The movement acquired by these first stop means 14 'with the first part 16 is therefore independent of the movement of the connection means 13 ', which has the advantage by compared to the previously shown achievements of being able to adjust the speed of displacement imposed on the movable contact of the vacuum switch by playing only on the characteristics of the second spring without taking into account the mass or the speed that owns this first part 16.

Advantageously, the distance d ₁ + g authorized for the displacement of the first tubular support element 14'C along the fixed support element 50 exceeds a certain clearance referenced g, also called the separation clearance, the distance from separation d ₁ of the vacuum switch contacts. It should be recalled that this distance d ₁ is also the distance authorized for the displacement of the connection means 13 ′, and that consequently the separation clearance g corresponds to the distance which separates the first tubular support element 14 ′ from this connection means 13 ′ at the end of opening of the vacuum switch as shown in FIG. 16. An annular shoulder 52 is formed on the first part 50A of the fixed support element 50 in order to form a fixed stop end of travel to stop the movement of the first element 14'C and therefore stop the movement of the first abutment means 14 'as well as that of the first part 16 of the movement return means 15 shortly after the abutment of these first stop means 14 '.

The connection means 13 ′ comprises a main part 13 ′ A fixed to the movable contact of the vacuum interrupter, consisting of a cylindrical stud of the same axis as the axis A of the device and provided at one end with an annular shoulder next to the vacuum switch. The other end of this cylindrical stud can slide in a cylindrical cavity of the same diameter formed in the second part 50B of the fixed support element 50, while ensuring the electrical connection between the movable contact of the vacuum interrupter and the fixed contact 3 of the gas switch which is carried by the first part 50A of the fixed support element 50. This second part 50B is provided with second abutment means 19 'against which abuts the annular shoulder of the part main 13'A of the connection means 13 ', when the latter has traversed the insulation stroke d ₁ integrally with the movable contact of the vacuum switch.

To this annular shoulder of the main part 13'A is fixed a tie rod 13'B which integrally connects this part 13'A to a second tubular support element 13'C which constitutes a secondary part of the connection means 13 '. This second element tubular 13'C surrounds the fixed support element 50 and is capable of being moved along this last in the axial direction A. Its primary function is to allow transmission by means of connection 13 ′ the force exerted by the first spring 20 to maintain the vacuum switch contacts closed with a certain contact pressure. In this situation, it is indeed in abutment against the first tubular support element 14'C of first stop means 14 '. On the other hand, it accommodates the second spring 21 between its internal cylindrical surface and the external cylindrical surface of the second part 50B of the fixed support element 50, and comprises at its end opposite the first means of abutment 14 ′ an annular shoulder serving to maintain the second spring 21 in compression. Thus, the thrust exerted on this annular shoulder by the second spring 21 during its detent allows movement of the entire connection means 13 '.

As for the high voltage hybrid switching device shown on the Figure 12, the device of Figure 15 incorporates a volume 11C of pneumatic blowing booster in addition to the thermal blowing volume 11A, in an embodiment for which this volume of thermal blowing is immobile.

Figure 16, the device of Figure 15 is shown at the end of a process power interruption. This process started with the release of the operating rod of the gas switch, which enabled the moving contact of the switch to speed up gas thanks in particular to the thrust exerted by the first spring 20 on the means of movement return 15, the second part 17 of which is integral in movement with the rod maneuver. This first spring thrust was exerted throughout the course of the dead stroke D by each rod 14'A of the first stop means 14 'integrally with the first part 16 of the movement return means 15. As soon as the dead stroke D has been traversed, the relaxation of the first spring 20 was interrupted by the abutment of the first stop means 14 ', and the movement of the second part 17 has become independent of that of the first part 16 of the movement return means 15.

Then, this first part 16 has freely traveled an additional distance d ₁ + g integrally with the first stop means 14 ', mainly due to the kinetic energy previously acquired by this mobile assembly. The additional path of this assembly is interrupted by the fixed abutment formed by the annular shoulder 52, as mentioned previously, at a longitudinal position for which the volume 11C of auxiliary pneumatic blowing is reduced to its minimum. As in the embodiment shown in FIG. 12, the piston of the pneumatic blowing volume is formed by an annular wall of the first part 16 of the movement return means 15. It can be noted that the compression in the volume 11C makes it possible to slow down the speed of the mobile assembly of the first stop means 14 'before these are stopped by the fixed stop formed by the annular shoulder 52.

Such a fixed stop 52 is not essential, and one can envisage a slightly different embodiment in which the piston formed by the annular wall of the first part 16 abuts against the partition wall of the two blowing volumes 11A and 11C a once the additional journey d ₁ + g of the mobile assembly in question has been completed.

This figure 16 represents the end of the opening of the hybrid cut-off device, this which corresponds to an instant after the stage described above where the course of first stop means 14 'is interrupted. The movement of the mobile contact of the gas switch continued after this step, solidly with the rod operation 6 and the second part 17 of the movement return means 15, until a sufficient insulation distance is reached for the arcing contacts of the switch gas after the arc between these contacts has been blown out.

The movable contact of the vacuum interrupter has traversed the separation distance d ₁ integrally with the connection means 13 ', the latter being kept pressed against the fixed support element 50 thanks to the force exerted by the second spring. 21 in compression.

It is understood that the improvement according to the invention, which makes it possible to provide the dead-stroke connection means a translational movement independent of that of the connection means, can also be implemented on cut-off devices hybrid that does not incorporate an additional pneumatic blowing volume as per example the devices shown in Figures 8 and 9.

In Figure 17 is shown schematically an embodiment of a hybrid switching device which is functionally equivalent to the device shown in FIG. 13, and which includes an improvement according to the invention making it possible to prevent any rebound of the movable contact of the vacuum switch.

As with the device in FIG. 13, the gas switch 40 includes thermal blowing volumes 40A and pneumatic 40C which are movable with the rod operation 6 of the device. The fixed piston of the pneumatic blowing volume 40C is not not shown in the figure, but a piston such as the sealing element 41 of the Figure 13 may be perfectly suitable. Apart from the parts which are united in movement of the operating rod, most of the elements of the cut-off device hybrid shown in Figures 17 and 18 is identical to the elements of the device of the figures 15 and 16. We can therefore refer to the comments on these figures 15 and 16 for the understanding of how this device works.

Unlike the embodiment in FIG. 15, the additional path d ₁ + g of the mobile assembly which includes the first stop means 14 ′ as well as the first part 16 of the movement return means is not interrupted here. by the annular shoulder 52, but by another annular shoulder 53 which forms a fixed stop at the end of the fixed support element 50. This fixed stop 53 is indeed dimensioned to stop the translational movement of the first part 16 at the end of the additional course of the mobile assembly, knowing that this movement is not here braked by compression in the pneumatic blowing volume.

Figure 18, the device of Figure 17 is shown at the end of contact opening the gas switch. For the understanding of the stages of the operation of the means displacement which are connected to the connection means 13 'and to the operating rod 6 of the device, reference may be made to the same as the comments in FIG. 16.

It may be noted for this embodiment that it is advantageous for the annular shoulder 52 to be positioned so as to leave only a very small clearance with the first tubular support element 14'C once the additional path d ₁ + g effected by the first abutment means 14 ′, this making it possible to prevent this element 14 ′ C from continuing its translational movement by compressing the first spring 20 due to its kinetic energy.

The decoupling clearance g allows in particular to tolerate slight rebounds of the first abutment means 14 ′ integrally with the first part 16 at the end of the additional path d ₁ + g of this mobile assembly. Indeed, such rebounds from a distance less than this clearance g will not affect the abutment of the connection means 13 'and therefore do not present the risk of reducing the distance between the contacts of the vacuum interrupter.

Figure 19, another embodiment of a hybrid breaking device according to the invention is shown diagrammatically and in partial view. The complete device can be extrapolated from the one shown in Figure 17 and which is functionally equivalent, the blowing nozzle 40B being movable with the operating rod of the device for each achievement. Structural differences relate to making contacts of arc 3 'and 4 of the gas switch, the latter being here arranged end to end. We can refer to figures 9 and 7 for an understanding of the arrangement of the contacts which are support against each other, in particular as regards the structure of the means 18 'which maintain pressure between the arcing contacts of the gas switch to resist electrodynamic forces during current flow. The structure of these means 18 'in FIG. 19 is similar to that of the means 18 for delaying the setting in movement of the movable contact in FIG. 7.

In this case, the movable contact 4 is directly fixed to the operating rod. 6 and is therefore permanently secured in translation of the rod. We can note that this realization with contacts arranged end to end allows to obtain a blowing volume relatively large thermal 11A for a limited radial size of the device, but this implies a significantly more complex realization than with contacts fitted as in Figure 13.

The means 18 ′ for maintaining contact pressure are mounted on the first part 50A of the fixed support element 50, and support at one end the third arcing contact 3 'which is not here completely fixed unlike the embodiments preceding. These means 18 'are arranged to allow the third arcing contact 3' to be moved with the fourth arcing contact 4 until the separation of these contacts, and to be then kept immobile in abutment after this separation while the fourth contact continues to run together with the operating rod during an interruption of current through the device.

In the present embodiment, we qualify the third arcing contact as quasi-fixed. 3 ', since the latter is only mobile during a relatively small part of the race total traversed by the movable arcing contact 4. This third arcing contact can therefore be considered almost fixed with respect to the fourth arcing contact. We can note that in similar embodiments of means 18 for maintaining contact pressure known from In the state of the art, an almost fixed arcing contact is also sometimes called semi-fixed contact.

For a hybrid switching device according to the invention, the production of the contacts of the gas switch arc will generally be able to call on one or the other of the two techniques illustrated here, in this case the press-in contact technique with a certain overlap distance or that of the contacts arranged end to end with means for maintaining contact pressure.

Figure 20, another embodiment of a hybrid breaking device according to the invention is shown in an embodiment for which the device is intended for a use as generator circuit breaker in a medium voltage network. Ways displacement which are connected to the connection means 13 'and to the operating rod 6 of the device are arranged here so that the separation of the contacts of the vacuum interrupter is significantly delayed compared to the separation of the arcing contacts from the gas switch.

Indeed, the overlap distance D _r of the contacts 3 and 4 of the gas switch is here less than half of the dead travel D of the first stop means 14 '. It will be recalled that this overlapping distance is also called the speed-up distance, in particular in the case of an equivalent embodiment where the contacts of the gas switch are arranged end to end. In general, for these applications of the device as a generator circuit breaker, it will be preferable to choose a dead travel D greater than twice this speed-up distance of the movable contact of the gas switch.

This implies that an electric arc is formed between the contacts of the gas switch. which are already separated by a certain distance before the dead travel D is completely traveled, i.e. before the separation of the contacts of the vacuum interrupter. The gas switch is therefore able to cause the current to flow through zero before that the vacuum switch does not cut the current, which is an advantage in the context of a use as generator circuit breaker.

It should be emphasized that a device of this type must be capable of cutting short-circuit currents with strong asymmetries which cause zero crossings of the delayed current. The hybrid switching device shown makes it possible to reduce the asymmetry of the current and to cause the zero crossing of the current earlier, at a compatible time with the operation of the vacuum switch.

The components of the device are essentially similar to those of the device of FIGS. 15 and 16, with the notable difference that the volume of thermal blowing 11A is not supported by an additional pneumatic blowing volume. Indeed, unlike this previous device, the gas switch is not asked here for cut low currents because in a medium voltage network this role is ensured by the vacuum switch which is also capable of holding the voltage restored.

Thus, the wall forming the bottom of the thermal blowing volume 11A does not have no opening. In addition, the first part 16 of the movement return means has at least one opening to balance the gas pressure between the volume inside this part 16 and the volume outside the displacement means, as well as in the device of FIGS. 17 and 18.

The length of the sliding rod of the first stop means 14 'must be extended relative to the device of FIG. 15 so as to allow the lengthening of the dead stroke D, and the characteristics of the first spring are provided so that this spring always exerts sufficient pressure on the vacuum switch contacts even when it has relaxed from a distance close to this distance D just before the separation of these contacts.

A hybrid cut-off device according to the invention allows the thermal phase of the cut-off of the current, that is to say the period of a few microseconds during which the restoration of the voltage begins, to be largely ensured by the vacuum switch of the device. For its part, the gas switch contributes essentially to the resistance to the peak value of the voltage, thanks to the relatively large contact separation distance inherent in this type of device in comparison with a vacuum switch. This in particular offers the possibility of using a gas other than SF ₆ for blowing the gas switch. In fact, SF ₆ is generally chosen for its properties of resistance to rapid rates of recovery of the voltage during the thermal phase of the cut. Since the resistance of the transient recovery voltage during the thermal phase is provided by the vacuum interrupter in a hybrid breaking device according to the invention, another gas or mixture of gases having sufficient dielectric properties can then be used in the gas switch of the device. Nitrogen under high pressure has the dielectric properties required at high voltage. Not presenting any risks for the environment, it constitutes a preferential solution for a use with a gas other than SF ₆ . Alternatively, a mixture composed of more than 80% nitrogen and another gas such as SF ₆ has at least the advantage of considerably reducing the risks for the environment compared to the use of pure SF ₆ .

Claims (19)

Hybrid type switching device for high or medium voltage, comprising an envelope (12) filled with a dielectric gas and having a longitudinal axis (A), a vacuum switch (10) disposed in the casing, comprising a first pair of arcing contacts consisting of a first contact (1) which is fixed and a second contact (2) which can be moved in translation in the axial direction (A), means provided for exerting on said second contact (2) a force such that the mutual pressure between the bearing surfaces of said first and second contact is greater than a determined value as long as said vacuum switch authorizes the passage of current, a gas switch (11, 40) disposed in the envelope, comprising a second pair of arcing contacts consisting of a third contact (3, 3 ') which is fixed or almost fixed and of a fourth contact (4 ) which can be moved in translation in the axial direction (A), an operating rod (6) connected to the fourth contact (4) and which can be immobilized or moved in translation by control means (8), characterized in that it further comprises a connection means (13 ') electrically connecting the second (2) and third (3, 3') contacts, able to be moved in translation in the axial direction (A) integrally with the second contact, displacement means connected to said connection means and to said operating rod to move them so as to separate the second and fourth contacts respectively from the first and third contacts, comprising dead travel connection means connecting said connection means (13 ' ) to said rod (6), these connecting means making it possible to move the rod by a determined dead stroke (D) while acting on said connection means to keep the vacuum switch closed during this movement, and in that once said dead travel (D) has passed through said rod (6), said dead travel connection means are capable of acquiring a translational movement in the axial direction (A) which is independent of the movement acquired simultaneously by said connection means (13 '). Cut-off device according to claim 1, intended for use as circuit breaker in a high voltage network, in which said displacement means are arranged so that the contact separations of the vacuum switches respectively (10) and gas (11, 40) occur simultaneously or slightly over time. Cutting device according to one of claims 1 and 2, wherein said means of dead travel linkage comprise movement return means (15) which cooperate with first elastic means capable of acting on said means of connection (13 ') to keep the vacuum switch closed, and include first abutment means (14 ') on which said first elastic means are based for exert a force on said connection means, said first stop means (14 ') being able to cancel said force once said dead travel (D) has been completed. Cut-off device according to claim 3, in which the said return transmission means movement (15) comprise two parts (16, 17) capable of being moved together in support one against the other and able to be dissociated after the beginning of the opening of the vacuum switch (10). Cutting device according to claims 3 and 4, wherein said first stop means (14 ') comprises at least one dead-stroke rod (14'A) which is integral with the movement of a first part (16) of said return means movement (15) and which comprises at one end a head (14'B), and comprise a first tubular support element (14'C) which is able to be moved in the axial direction (A) along a fixed support element (50) which it surrounds, said first tubular element having an annular part which is traversed by said dead stroke rod and against which said head is able to come to bear in abutment once said stroke is dead (D) traveled. Cut-off device according to one of claims 3 to 5, in which said displacement means comprise second elastic means capable of separating the contacts (1, 2) of the vacuum interrupter (10) as soon as the rod (6) maneuver traversed said dead travel (D) and able to move said connecting means (13 ') and the second contact (2) of an insulation stroke (d ₁ ) determined relative to the first contact (1) during a current interruption by the device, said isolation stroke corresponding to the complete separation distance of the first and second contacts. Cutting device according to one of claims 5 and 6, wherein said first elastic means comprise a first spring (20) which is arranged in compression between the annular part of said first tubular support element (14'C) and the first part (16) of said movement return means (15). Cutting device according to claims 6 and 7, wherein said second means elastic comprises a second spring (21) which is arranged in compression between a second part (50B) of the fixed support element (50) and an annular part of a second tubular support element (13'C) which surrounds said fixed support element, said second tubular support element being able to be moved along said second support element fixed in the axial direction (A) and being integrally connected by at least one tie rod (13'B) to a main part (13'A) of the connection means (13 '). Cutting device according to one of claims 5 to 8, wherein said first and second tubular support elements (13'C, 14'C) are stationary in abutment against one another as long as said dead travel (D) has not been covered by said operating rod (6) during a power interruption by the device. Cutting device according to claims 8 and 9, wherein said second part (50B) of the fixed support element (50) is provided with second abutment means (19 ') against which the main part abuts (13'A ) of said connection means (13 ′) when the latter has traversed said insulation stroke (d ₁ ). Cutting device according to one of claims 8 to 10, wherein said first part (50A) of the fixed support element supports the third arcing contact (3, 3 ') and is supported by said second part (50B) of this fixed support element thanks to fixing means (51) arranged along the axis (A) of the device, said second part being held fixed by an insulating tie rod (30 ') which is fixed to one end of the device. Cut-off device according to one of claims 6 to 11, in which a first part (16) of said movement return means (15) is capable of moving over a total stroke which is greater than the sum of the dead stroke (D) and the stroke insulation (dl) that the second contact (2) can travel. Cut-off device according to one of claims 4 to 12, in which a second part (17) of said movement return means (15) is integral in translation with the operating rod (6). Hybrid switching device according to one of claims 1 to 13, in which the device also comprises an additional pneumatic blowing volume (11C, 40C), adjacent to said thermal blowing volume (11A, 40A) and capable of communicating with the latter, delimited by a fixed or movable bottom which is capable of being brought closer to the volume of thermal blowing to compress the dielectric gas contained in said volume of pneumatic blowing during a power interruption by the device. Hybrid switching device according to one of claims 1 to 14, in which the contacts (3, 4) of the gas switch (11, 40) are fitted one inside the other in position closed with an overlap distance which is less than or equal to said dead travel (D). Hybrid switching device according to one of claims 1 to 14, in which the contacts (3, 4) of the gas switch (11) are in abutment abutting one another closed position, and in which means for delaying (18) the setting in motion of the fourth contact (4) are interposed between this contact and said rod (6). Hybrid switching device according to one of claims 1 to 14, in which the arcing contacts (3 ', 4) of the gas switch are in abutment against each other in closed position, and in that means (18 ') for maintaining contact pressure are arranged to allow an arcing contact (3 ') to be moved with the other contact (4) up to the separation of said contacts (3 ', 4) and to be held stationary after said separation. Cut-off device according to one of claims 1 and 3 to 17, intended for a use as generator circuit breaker for medium voltage network, in which said displacement means are arranged so that the separation of the contacts (1, 2) from the vacuum interrupter (10) occurs significantly delayed with respect to the separation of the arcing contacts (3, 3 ', 4) of the gas switch (11, 40), so that the passage zero current is caused by the gas switch before the vacuum switch cut the power. Cutting device according to claim 18, wherein the first means for stop (14 ') of the dead-stroke connecting means are arranged so that said dead-stroke (D) is greater than twice the speed-up distance (Dr) of the movable contact of the gas switch.

Images