FR2882852A1 - Gas insulated switchgear busbar and high voltage circuit breaker arcing chamber connecting system, has semi-automatic type coupler including balls cooperating with groove and pushrod to maintain bar in connected position - Google Patents

Abstract

The system has a support block connected to busbars. A hollow tube shaped bar (22) is provided with electrical contacts and slides relative to the support block. One electrical contact is connected to a plug-in connector of an arcing chamber. A semi-automatic type coupler includes balls that cooperate with a groove and a push rod to maintain the bar in a connected position during assembling and disassembling of the contacts. An independent claim is also included for a circuit breaker comprising a connecting system.

Description

CONNECTING A CUTTING CHAMBER OF AN APPLIANCE

BLINDED SWITCHING

DESCRIPTION 5 TECHNICAL FIELD

  The invention relates to the field of metal insulated switchgear switching equipment, also known by the acronym GIS (Gas Insulated Switchgear).

  The invention relates more particularly to the connection between the active part and the busbar of a switchgear, for example the breaking chamber of a circuit breaker.

  In particular, the system of the invention has a new feature relating to the maintenance of this type of equipment, with a simplification of the establishment and the output of the active part.

  STATE OF THE PRIOR ART A gas-insulated metal-enclosed switchgear is known, for example, from document EP-A-0 688 071: as shown schematically, for example in FIG. 5 of this document, a circuit-breaker (6) can thus have a active part, or breaking chamber, (66) located in a metal shell filled with insulating gas, which connects two remote electrical contacts (20, 70). The metal shell (18, 68) is composed of several parts, and in particular comprises a cover (75) at one of its ends. A mechanism (77) on the cover (75) actuates a rod (78) for transmitting the electrical potential between the remote connectors (20, 70), or isolating them.

  During assembly, the interrupting chamber in its entirety is inserted along the axis (13) in the envelope by the cover (75), then fixed and secured to the electrical connections (20, 70).

  For maintenance operations, whether preventive or corrective, the steps are reversed. It thus quickly appears that the removal of the active part is a heavy and complex process because of the necessary disconnections, in particular at the contact (70) located perpendicularly to the axis (13) of the interrupting chamber: an opening of the connection (69) concerned is necessary. This procedure is therefore particularly long and expensive, especially for compact GIS type equipment.

  DISCLOSURE OF THE INVENTION The invention proposes a connection system making it possible to overcome the disadvantages of existing equipment. The system according to the invention, while reducing the maintenance procedures, is remarkably simple to manufacture and inexpensive.

  In an advantageous mode, the system is easily accessible, which allows a reduction in the cost and time of intervention on a site. In another advantageous mode, despite its simplicity, the system is reliable thanks to a lock in the service position, and in the maintenance position.

  More specifically, the invention in one of its aspects relates to a connection system between a busbar and the active part of a circuit breaker. The system according to the invention comprises a connection in at least two parts, a part serving as support for the busbar, and a bar-shaped part provided with an electrical contact that can be connected to the active part. The two parts of the coupling are slidable relative to each other.

  Advantageously, the support portion is in the form of a tube mounted telescopically around the bar.

  The invention also relates to a cell comprising a connection system held in an envelope, advantageously in a metal envelope.

  In another aspect, the invention relates to a circuit breaker comprising such a connection system or such a cell and an active portion comprising a contact that can be connected to the connection system.

  In a preferred aspect, the connection system according to the invention can be accessible from the outside to ensure the displacement. To this end, the bar is provided with a lug that can be engaged with a tool to be moved. The lug can be in the form of a displacement axis which passes through the inside of the bar formed in a tubular manner; an opening on the wall of the bar allows access to the axis.

  In the case where the system is kept in an envelope, an access, advantageously provided with a tight cover, is located on the wall of the envelope at the opening of the bar. An indexing system can be coupled to the envelope.

  The invention in another aspect relates to tooling adapted to the system: the tool can take the form of a key that cooperates with the lug and the openings, as well as with the possible indexing system.

  In a preferred embodiment, the connection system according to the invention comprises a locking mechanism at the bar that moves. In order to maintain the connected state, the bar may comprise at its end at least one ball cooperating with a groove and a pusher. Advantageously, a return spring makes it possible to position the ball in the locking position in the absence of a disconnection bias.

  Advantageously, the locking mechanism is positioned at a female contact part of the displacement bar, and cooperates with a male contact part on the active part of the circuit breaker. The male part comprises in this case a groove which can accommodate the balls in the locking position.

  In a particularly preferred manner, the locking mechanism is present in conjunction with the movement lug, and is biased to unlock the system when moving tools. is put in place. For example, the pusher is located at the displacement lug and the return spring is compressed when the tool comes to engage the lug.

BRIEF DESCRIPTION OF THE DRAWINGS

  The features and advantages of the invention will be better understood on reading the description which follows and with reference to the accompanying drawings, given by way of illustration and in no way limitative.

  Figure 1 schematically illustrates the lateral connection between the active part of a high-voltage circuit breaker and a busbar according to the state of the art.

  Figure 2 shows the same part in a system according to the invention.

  FIGS. 3A and 3B show a connection system according to one embodiment of the invention comprising an automatic locking mechanism, respectively in connected mode and during unlocking and disconnection.

  DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS The system according to the invention is particularly suitable for a high-voltage circuit breaker, and will be described for this application. However, it will be clear to those skilled in the art that other configurations may be envisaged. Only a portion of a circuit breaker is shown below: the unillustrated portion can take known shapes or alternatives, and does not affect the connection as specified in the invention. Most elements of the circuit breaker are also schematized for similar reasons.

  A high-voltage circuit breaker 1, illustrated in FIG. 1, is in the general form of a metal casing 2, one end of which comprises a removable cover 3, or bottom of the tank, held on the casing 2, for example by screwing to keep a sealed enclosure in which is maintained an insulating gas under pressure.

  The active part 4 of the circuit breaker 1 is in a longitudinal shape along an axis AA, between a first end adjacent to the cover 3, and a second opposite end. The breaking chamber 4 comprises various elements that will not be detailed, but in particular two parts movable relative to each other to provide an electrical connection or a cutoff, the actuation being done via a mechanism 5 accessible from outside the casing 2 and a movable rod 6.

  The active part 4 is connected, at its second end (not shown) to an electrical pole, and transmits - or not - the current between this pole (not shown) and another electrical equipment. To this end, the metal casing 2 is provided with a lateral branch 7 allowing the passage to a set of bars 8 which transmits the current to the other apparatus.

  The busbar 8 is held in a cell 9 whose walls are unitary or integral with the metal shell 2. The busbar 8 is connected to the breaking chamber 4 via an electrical connection 10 comprising a internal portion 11 serving as a contact block with the busbar 8 and a portion 12 projecting out of the cell 9; the two parts 11, 12 are secured to each other, for example by screwing, to form the connector 10. The connector 10 is held by an insulating wall 13, usually in conical form, which separates the envelope 2 of the enclosure 9.

  On the active part 4 of the circuit breaker 1 is a radial connection portion 15 comprising a recess 16 in which can be inserted the electrical contact 10 of the busbar 8; the electrical connection is made on a portion of the recess 16 serving as socket 17.

  To dismount such a system, as deduced from FIG. 1, after having removed the bottom of the tank 3 to extract the whole of the active part 4 of the circuit breaker 1, it is necessary to remove the contact block 10 fixed on the insulating support 13: the busbar 8 located above the lateral output of the circuit-breaker 1 must thus be pulled out, which amounts to removing an assembly of the cell 9 from the switching equipment 1.

  Disassembly of elements that are not affected by the repair and / or in service of the interrupting chamber 4 is necessary, which proves to be costly, and may cause further damage.

  One solution to avoid unnecessary maneuvers would be to mount the active part 4 of the circuit breaker 1 by means of a knife and a plier that can be slid out by sliding, and not by a connector 10 inserted into a recess 16 This reliable solution is, however, expensive.

  In order to shorten the interruption time as much as possible for preventive or corrective maintenance operations while keeping costs minimal, the invention proposes a modification of the connection between the active part of the circuit breaker and the electrical contact. In particular, the connection system is such that the electrical contact connected to the busbar is movable without having to modify the position of the busbar itself, and thus keeping the corresponding cell in the state. Advantageously, a suitable tooling allows this setting in motion of the movable contact so as to leave enough space to extract the active part.

  As shown diagrammatically in FIG. 2, the contact block 10 of the state of the art is replaced by a telescopic connector system 20. The active part 4 of the circuit breaker can remain of identical construction to that known, even if arrangements can be made. be preferred for preferred embodiments; in particular, a protruding part 15 with a recess 16 allows the connection with the electrical connection 20 of the busbar 8.

  Advantageously, this projecting portion 15 is in the form of a centering cone.

  In the recess 16 of the contact part of the breaking chamber 4 is located a bar 22 provided with at least a first electrical contact 24.

  The contact bar 22 is preferably in the form of a cylindrical metal tube, for example of aluminum or copper, whose section at a first end is complementary to the recess 16. The first electrical contacts 24 are adapted to the mechanical catch 17 located at the active part 4 of the circuit breaker, for example of complementary shape; an example will be described in more detail below.

  The second end of the contact bar 22 cooperates with a support block 26 of the busbar 8. The connection system 20 is preferably such that the contact bar 22 slides inside the block 26 on a certain length d. The sliding support 26 can take any suitable shape, such as a tube, and is preferably made of aluminum or copper, advantageously in the same material as the sliding bar 22.

  The displacement bar 22 is manufactured and arranged so as to be able to go up in the support 26 enough to disconnect it from the projecting connector 15 and thus to be able to extract the active part 4 of the circuit breaker without being obliged to dismantle the ferrule placed on the output side 7 of the tank 2 of the circuit breaker. That is to say that the bar 22 fits into the support 26 with a length d greater than the depth of the recess 16; the relative dimensions result from the physical parameters of the various components of the circuit breaker.

  The connection system 20 further comprises means 30 for sliding the contact bar 22, and to control the movement of this bar 22 along its axis BB. The means 30 comprise. advantageously a lug 32 which can be engaged by a key-type device 34. The lug 32 is preferably in the form of a cylindrical receiving axis passing through the interior of the tube 22. On the wall of the tube , at the axis 32, there is an opening 36 allowing communication between the lug 32 and the outside of the bar 22, that is to say the cell 9. The opening 36 is studied and configured in order to ensure the optimal dielectric conditions for the contact, that is to say in particular by removing the sharp edges and optimizing its geometry by flat and rounded.

  In order to allow movement of the bar 22, the wall of the cell 9 further comprises an access 38 to the displacement means 32, 36 for a tool 34. Advantageously, this access 38 is composed of a tapping on the vessel 2 of the circuit breaker and provided with a removable sealing cover. The access 38 is located opposite the opening 36.

  When a withdrawal of the active part 4 is desired, a tool 34 of the key type is put in place by the access 38 and the opening 36, and engages with the pin 32. By leveraging, the pin 32 and therefore the bar 22 are moved along the axis BB to the support 26. As soon as the displacement is greater than the distance separating the first end of the tube 22 and the top of the projection 15 in the connected position, the contact bar 22 out of the projection 15: it is then possible to extract the pole 4 of the circuit breaker in its entirety. Advantageously, the openings 36, access 38 and pin 32 are positioned and dimensioned so as to allow a rise of the bar 22 of the order of 5 cm for a high-voltage circuit breaker, the projection 15 is usually slightly lower. The key 34 is of suitable material, for example steel, for the effort required to raise the bar, preferably of the order of 15 to 20 daN.

  Preferably, an indexing system 40 makes it possible to locate the positions of the bar 22 in connected and disconnected positions according to the position of the tool 34. The indexing system 40 may for example comprise a rule 42 provided with pins 44 and secured to the casing 2 of the circuit breaker. The pivot axis 46 of the key 34 for levering is preferably at a fixed position, for example at the access cover 38. The indexing system 40, and in particular a pin 44 integral with the key 34 at an orifice 48 thereof, can further ensure the locking of the bar 22 in the disconnected position (in dashed lines in Figure 2), to ensure the free passage of the interrupting chamber 4.

  The upper block 26 of the sliding contact guiding and maintaining the centering of the bar 22 when it separates from the projection 15 of the cutting chamber 4. In addition, the upper contact 26 also serves to support the electrical connection 20 ; it is therefore possible to remove the insulating cone 13 as it was present in the prior art (see Figure 1): this embodiment shown schematically in Figure 2 is advantageous from a cost point of view, even if the volume of Insulating gas present, for example SF6r in the metal shell 2 is slightly increased.

  For reasons of electrical safety, and in particular the risk of unwanted rise of the bar 22, when the connection is stressed, for example subjected to vibration forces or electrodynamic forces, a locking of the bar 22 in the connected position may be provided, preferably with automatic unlocking before disconnection.

  This locking function can be provided by a ball coupler 50 semi-automatic type.

  As illustrated in FIGS. 3, this coupler 50 may comprise a plurality of balls 52, advantageously arranged along a circumference, and cooperating with a groove 54. Preferably, the contact 24 of the bar 22 is arranged as a female part. and is secured with a mechanical catch in the form of a protuberance 17 located at the bottom of a recess 16 in which the displacement bar 22 is inserted; the bar 22 advantageously comprises a centering cone 56 of insulating material adapted to engage on the protuberance 17, and around which a cylindrical portion 58 is slidable.

  To allow the locking, the balls 52 are biased inside the groove 54. For this purpose, the cylindrical portion 58 comprises an inward projecting portion 60 which presses the balls 52 radially in the groove 54; the balls 52 are also maintained in the longitudinal direction relative to the distal end of the bar 22 by a recess on the centering cone 56. Preferably, the ring 58, 60 is coupled in translation relative to the centering cone 56 by spring means 62, which causes the locking device 50 to rest at a position in which the balls 52 are in the groove 54 (Figure 3A).

  The cylindrical portion 58 is furthermore coupled by a rod 64 to a pusher 66 in order to be displaced along the axis BB, in particular in a direction opposite to the spring means 62, thereby to unlock the device 50 by disengaging the balls 52 throat 54.

  The pusher 66 may advantageously be actuated by the tool 34 when it is put in place. In particular, the pusher 66 may be located on the sliding axis BB, at a distance from the displacement pin 32 less than the width of the engagement portion of the key 34: during the engagement between pin 32 and tooling 34 schematically in FIG. 3B, the key 34 moves the pusher 66 away from the desired movement (downward in the figure, while the disconnection involves upward movement) along the axis BB. This reverse movement is preferably associated with the compression of a spring 68 of stroke also allowing the automatic return to the locking position in the absence of stress. During this unlocking step, the ball 52 deviates from the groove 54 towards the bar 22 by releasing the passage of the male end 17 out of the centering cone 56 and the tubular portion 58.

  The bar 22 can then be disconnected by raising it with the aid of the wrench 34: the pivoting of the wrench 34 engaged with the lug 32 about its axis 46 makes the whole of a sufficient value breaking chamber 4, that is to say of a sufficient value so that the lower end of the bar 22 is located above the upper end of the projection 15, 17 of the socket.

  A new complete pole can then be introduced inside the tank 2 and fixed. The key 34 is used to press again the pusher 66 and compress the spring 68: the operation of the tool 34 allows the descent of the bar 22 which finds its housing vis-à-vis, thanks in particular to the upper guide by the support block 26, and the centering cone 56.

  The bar 22 being: abutting on the contact piece 15, which can be confirmed by the location of the bar position connected to the indexing means 40, the operating key 34 can be removed. The projection 60 is biased by the spring 62, the ball 52 rolls in the groove 54 of the nozzle 17, and holds solidly the bar 22 fixed on the socket 17: Figure 3A.

  Then simply replace the lid 3 closure to complete the intervention, and fill the envelope 2 of insulating gas if necessary.

  This embodiment is of course only an alternative, and it is possible to resume the conventional assembly of the couplers by envisaging the unlocking by pulling on the ring 62, the female body being mounted in the opposite direction and the male end 17 penetrating on the other side.

  Due to the fact that the active part of the circuit breaker can be disconnected simply, the maintenance intervention is greatly facilitated. In addition, the tooling is simple and secure design, also meeting the specifications requested on metal-encased posts, which is all the more in the direction of the economy.

  Although described in combination, it is clear that alternatives are possible and that the various functionalities can be used separately. In particular, the described locking device can be used for other connections in switching equipment. For example, in the case of a bar mounted in an envelope with contacts at each end, during assembly or disassembly of one of the two end contacts, the locking device can be used to hold the bar fixed on the contact not disassembled, thus eliminating the risk of finding the bar at the bottom of the envelope; the lock can be pushed with a rod if you want to remove the bar from the locked side.

  It is also possible to replace the geometry of the elements presented by alternatives. For example, the contact portion 15 may comprise a recessless projection, or the bar 22 may be solid and include two outer grooves holding a wrench 34 which engages around the bar 22. Another option is the design of a unlocking the bar by pulling on a cable or a tie rod in place of the latch pusher.

Claims (17)

  A system (20) for electrical connection with an interrupting chamber (4), comprising a coupling which extends between two ends, which is provided at a first end with a first electrical contact (24) which can be connected mechanical coupling (17) of an interrupting chamber (4), and at the second end of a support (26) which can be connected to a busbar (8), characterized in that the connection ( 20) comprises a bar (22) provided with the first electrical contact (24) and a block (26) at its second end comprising the support, the bar (22) slidable relative to the block (26).   2. System according to claim 1 wherein the block (26) is in the form of a tube telescopically mounted with the bar (22).   3. System according to one of claims 1 or 2 wherein the bar (22) further comprises a lug (32) displacement.   4. The system of claim 3 wherein the bar (22) is in the form of a hollow tube, the lug (32) is located inside the tube (22), and the tube (22) comprises a lateral opening (26), so that the lug (32) is accessible from the outside (9) of the tube.   5. Cell (9) circuit breaker comprising a casing (2) and a system (20) according to one of claims 1 to 4 located in the casing (2).   6. Cell (9) comprising an envelope (2) and a system (20) according to one of claims 3 or 4 located in the envelope (2), the envelope (2) comprising an access (38) provided with a tight cover positioned so that a tool (34) passing through the access (38) can be secured to the lug (32).   7. The cell of claim 6 further comprising an indexing system (40) of the position of the bar (22).   8. Key (34) adapted for a cell (9) according to one of claims 6 or 7 comprising an end capable of cooperating with the lug (32), and possibly the indexing system (40).   9. System according to one of claims 1 to 4 wherein the first end of the bar (22) comprises a locking device (50) capable of cooperating with the mechanical catch (17).   10. The system of claim 9 wherein the locking device (50) comprises at least one ball (52) cooperating with a groove (54) and a mechanism (58, 60, 64, 66) capable of forcing the balls (52). ) in and out of the throat (54).   11. System according to claim 10 comprising a return spring (62) of the balls (52) in the groove (54).   12. Circuit breaker comprising a system according to one of claims 1 to 4 or 9 to 11 or a cell according to one of claims 5 to 7, and a breaking chamber (4) provided with a mechanical latch (17) can cooperate with the system (20).   Circuit breaker according to Claim 12, in which the mechanical catch (17) is in the form of a protruding part (15) provided with a recess (16) which can receive the bar of the system (20).   14. Circuit breaker according to one of claims 12 or 13 wherein the mechanical attachment comprises a male portion (17) and wherein the first contact (24) of the bar (22) of the system (20) comprises a female part ( 56, 58) cooperating with the male part (17) of the mechanical catch.   The circuit breaker of claim 14 wherein the female portion (58) includes an internal projection (60), and the male portion (17) includes a groove (54).   16. Circuit breaker according to claim 15 comprising at least one ball (52) and a return spring (62), a pusher (66) connected to the female part (58), the ball (52) being able to cooperate with the groove (54) and the protrusion (60) of the female part (58) to ensure relative locking or unlocking between the bar (22) and the active part (4).   17. Circuit breaker according to claim 16 wherein the bar (22) comprises a displacement pin (32) which is capable of cooperating with the pusher (66).