EP4372778A1

EP4372778A1 - Load break or short-circuit currents switch and electrical equipment incorporating said switch

Info

Publication number: EP4372778A1
Application number: EP22753720.6A
Authority: EP
Inventors: Javier Larrieta Zubia; Severo Aranaga Lopez; Sergio BARRIO RODRIGUEZ; Jesús IZCARA ZURRO; Asier Bilbao Lezeta
Original assignee: Ormazabal Corporate Technology AIE
Current assignee: Ormazabal Corporate Technology AIE
Priority date: 2021-07-13
Filing date: 2022-07-07
Publication date: 2024-05-22
Also published as: WO2023285716A1; ES1275577Y; ES1275577U

Abstract

Load break or short-circuit currents switch (1) which can adopt at least three operating positions, making - breaking - disconnecting, as well as a fourth grounding position, in the latter case including a grounding contact, thus compactly arranging a load break or short-circuit currents switch capable of executing up to four operating positions (making, breaking, disconnecting and grounding) and that basically comprises a main circuit (2) for the circulation of electrical current and a secondary circuit (3) for circulation of electrical current in shunt, wherein the main circuit (2) comprises a switch - disconnector (4) equipped with a fixed contact (5) and a moving contact (6), and wherein the secondary circuit (3) comprises a vacuum switch (7) that in turn comprises a fixed contact (8) and a moving contact (9), the vacuum switch (7) being actuated by moving the moving contact (6) of the switch - disconnector (4) through a control mechanism (10).

Description

OBJECT OF THE INVENTION

The invention relates to a load break or short-circuit currents switch, for application in electrical power distribution networks, comprising a main circuit for circulating electrical current and a secondary circuit for circulating shunt electric current. The main circuit comprises a switch - disconnector with a fixed contact and a moving contact, while the secondary circuit comprises a vacuum switch that is actuated by the moving contact of the switch - disconnector.
The load break or short-circuit currents switch of the invention can adopt at least three operating positions, making - breaking - disconnecting, as well as a fourth grounding position, in the latter case comprising a grounding contact, thus having a compact load break or short-circuit currents switch capable of executing up to four operating positions (making, breaking, disconnecting and grounding).
Another object of the invention is an electrical equipment, such as a cell, which incorporates said load break or short-circuit currents switch in an insulated housing in a dielectric medium.

BACKGROUND OF THE INVENTION

At present, the electrical switchgear used in electric power distribution networks is installed in enclosures that are usually metallic, called cells. Said switchgear comprises operating means that perform the functions of breaking - disconnecting - grounding of the installation.
On the one hand, operating means are used such as disconnectors that comprise two contacts that can be joined to allow the current to pass or leave a physical separation determined by the safety standard or the manufacturer to prevent the passage of current, and which also comprise a third contact for grounding the electrical circuit. But these disconnectors are sometimes not capable of performing the functions of the switch, that is, breaking the current when the circuit is on load or in the event of a fault due to overcurrent, if they have not been designed for it or do not have the appropriate extinguishing means.
It is known to use operating means based on SF6 gas contact separation technology in order to break the current (the current when the circuit is on load or fault current due to overcurrent). This solution has numerous advantages in terms of the compactness of the electrical switchgear, its cost and its performance, mainly due to the exceptional properties of SF6 gas, such as dielectric strength, thermal conductivity, chemical stability, etc. However, SF6 gas has the disadvantage of being part of the gases with a great environmental impact due to its high potential for greenhouse effect (GWP = 22800).
On the other hand, operating means constituted by vacuum switches are known, which consist of a bottle inside of which a pair of electrical contacts is housed, a fixed one and the other a moving one that moves by the actuation of an operating mechanism, to perform the breaking - making functions of the corresponding electrical circuit. But these vacuum switches are not used for current breaking functions when the circuit is on load due to their high cost.
In this sense, solutions are known in which a vacuum switch is placed in a secondary or shunt circuit in such a way as to guarantee the breaking of the electric current and at the same time reduce the cost of this technology because the vacuum switch used can be of lower performance by having to withstand the electric current for a shorter time. This secondary circuit is inactive in permanent regime and is only traversed by the electric current when the switch - disconnector arranged in a main circuit has begun its opening sequence, by means of a progressive transfer of electric current from the main circuit to the secondary circuit. As the vacuum switch is generally at rest, it does not have to be dimensioned based on the restrictive electrical and dielectric performance of the permanent regime, such as the short-circuit making capacity.
There are examples of the state of the art that deal with this type of solutions that comprise a main circuit equipped with a first operating means, such as a switch - disconnector, through which the electric current circulates in permanent regime and a secondary circuit equipped with a second operating means, such as a vacuum switch, through which the shunt electric current circulates, that is, in the switch - disconnector opening sequence, the moving contact of this last element intercepts, during its opening, a free end of the secondary circuit and the electric current begins to circulate through the secondary circuit at the same time as it circulates through the main circuit. In this way, following the opening sequence, the switch - disconnector is separated from the main circuit without producing any electric arc in the circuit. The continuation of the opening sequence and therefore the actuation of the moving contact of the switch - disconnector on the secondary circuit open the vacuum switch, interrupting the electric current, extinguishing the electric arc and thus obtaining the breaking operating position. Subsequently, the moving contact of the switch - disconnector is separated from the free end of the secondary circuit and allows the vacuum switch to close its contacts, but without the passage of electric current, since the secondary circuit remains open. At this moment, the disconnecting operating position has been obtained. In case of having a grounding contact, the moving contact of the switch - disconnector would follow its opening sequence and by intercepting said moving contact the grounding contact would obtain the grounding position.
In this sense, some documents of the State of the Art that describe this type of solutions can be cited, for example, ES2387862T3 , ES2526220T3 , ES2525080T3 , DE102004006476B4 or WO2006074975A1 .
In document ES2387862T3 the moving contact of the main circuit disconnector, in its opening sequence, intercepts / interacts with an actuating means arranged in the branch of the secondary circuit and which is associated with the vacuum switch by means of a kinematic chain or movement transmission system to act on the moving contact of said vacuum switch and cause its opening. The actuating means is arranged at the free end of the branch of the secondary circuit, connected to it by means of an articulated area provided with a stop that prevents the movement of the actuating means in the opening direction of the disconnector and a spring that allows the movement of the actuating means in the closing direction of the disconnector, and that once the actuating means of the moving contact of the disconnector is released, said spring makes the actuating means return to the stop position in the disconnector closing. The actuating means comprises a first face covered by a conductor directed towards the disconnector and a second face opposite the first one and covered by an insulator. In this way, when the disconnector is opened, its moving contact touches the actuating means on its conductive face and the current circulates through the branch of the secondary circuit at the same time as it circulates through the branch of the main circuit. Continuing with the opening sequence, the disconnector is separated from the branch of the main circuit without producing any electric arc in the circuit. The continuation of the opening sequence and therefore the action of the moving contact of the disconnector on the branch of the secondary circuit opens the vacuum switch, interrupting the electric current and extinguishing the electric arc. In this document ES2387862T3 , it is expected that the vacuum switch closes its contacts again just after the opening of the circuit, but without the passage of electric current, since the branch of the secondary circuit remains open. In the closing sequence of the disconnector, its moving contact touches the actuating means on its face covered by an insulator and therefore there should be no current flow through the branch of the secondary circuit, that is, the branch of the secondary circuit must be kept open since the vacuum switch includes its closed contacts and since it is not sized based on the restrictive electrical and dielectric performance of the permanent regime, such as the making capacity against short-circuit, the vacuum switch does not withstand the passage of a current of such magnitude with its contacts closed. Therefore, due to the separation of the contacts of the vacuum switch, an electric arc would form between the separated contacts, this being an undesirable phenomenon that should be avoided since the formation of the arc can destroy the insulation and the contacts, as well as produce a sudden increase in temperature and pressure that can lead to explosions that may cause material damage, the generation of toxic gases, and even personal injury. In this sense, in the case of document ES2387862T3 , there is the drawback that in the disconnector closing sequence the electrical insulation distance between the electrical components (between the moving contact of the disconnector and the conductive face of the actuating means) may not be enough and consequently there may be a leakage line that establishes the circulation of the current through the branch of the secondary circuit, thus originating the previously mentioned undesired phenomenon referring to the formation of the electric arc between the contacts of the vacuum switch.
Similarly, ES2526220T3 has a means for actuating the moving contact of the vacuum switch in the branch of the secondary circuit, with the difference that in this solution the moving contact of the vacuum switch remains locked in its open position until the main circuit disconnector executes the closing sequence. The purpose of this blocking is to protect against a possible rapid re-engagement of the secondary circuit. However, this blocking means that the vacuum switch is not ready for the next breaking operation and that the entire branch of the secondary circuit or shunt is not at the same electrical potential while the disconnector remains open.
It is the object of document ES2525080T3 to simplify the kinematic chain to transmit the movement of the moving contact of the disconnector to the moving contact of the vacuum switch. In the solution of this document, the number of elements of the kinematic chain (referred to as "control mechanism" in the document) is reduced, which comprises a rotary rocker arm as a means of actuating the moving contact of the vacuum switch, which connects a rod that is associated with the moving contact of the vacuum switch with the moving contact of the main circuit. In this way, a unitary and flexibly mounted rocker arm replaces a control mechanism made up of parts articulated with each other. As in the previous cases, the means for actuating the moving contact of the vacuum switch, specifically the rocker arm, is part of the branch of the secondary circuit, being the electrical conduction through the branch of the secondary circuit provided by the rocker arm or possibly by a conductive switching lug, electrically connected to the moving contact of the vacuum switch and extending to a free end superimposed approximately on a free end of the rocker arm that intercepts the moving contact of the main circuit, wherein this moving contact of the main circuit frictions over the free end of the switching lug.
DE102004006476B4 also defines a means for actuating the moving contact of the vacuum switch that is part of the branch of the secondary circuit, comprising in said secondary circuit the complete kinematic chain for the transmission of movement to the moving contact of the vacuum switch.
On the contrary, in document WO2006074975A1 the actuating means is part of the main circuit, since in this case the actuating means is a cam disc that is electrically and mechanically connected to the moving contact of the main circuit. The actuating means is arranged at the free end of the moving contact of the main circuit, connected to it by means of an articulated area provided with a stop that prevents the movement of the actuating means in the opening direction of the disconnector (in the same way as in the case of ES2387862T3 ) and a spring that returns it to the stop position when closing the disconnector. In this solution, the moving contact of the vacuum switch comprises at its free end an electrically conductive pin element that is intercepted by the cam disc in the opening sequence of the main circuit. In particular, the cam disc comprises a guide slot into which the pin element is inserted that, as the main circuit follows its opening sequence, is forced to go through said guide slot, transmitting said movement to the moving contact of the vacuum switch. In this way, the electrical current shunts through the pin element and the cam disc. In the closing sequence of the main circuit, the cam disc does not interfere with the pin element, so the vacuum switch is not subjected to any action and remains with its contacts closed. This solution, however, has the drawback that the guide slot of the cam disc has to have a path that is synchronized with the movement path of the moving contact of the main circuit, so that as said moving contact of the main circuit moves, the pin element is located at the appropriate point in the guide slot to convert the angular displacement of the moving contact of the main circuit into linear displacement that the pin element must transmit to the moving contact of the vacuum switch. Also, the vacuum switch is fixed, that is, the vacuum switch does not comprise any movement, so the guide slot must be more precisely traced and thereby the inconvenience related to synchronization is reinforced.

DESCRIPTION OF THE INVENTION

The load break or short-circuit currents switch object of the present invention is applicable in electrical power distribution facilities such as, for example, electrical transformation centers, distribution centers, substations, etc., for the protection and operation of electrical circuits, and solves each and every one of the problems mentioned above, so that the switch of the invention comprises a kinematic chain or simplified movement transmission system to act on the moving contact of the vacuum switch and cause its opening, it avoids the problem related to a possible current spark-over between the moving contact of the switch - disconnector and the secondary circuit in the switch closing sequence and allows the vacuum switch to close its contacts once the disconnecting operating position has been obtained by the switch of the invention, thus leaving the vacuum switch ready for the next breaking operation.
The switch of the invention comprises a main circuit for the circulation of the electric current and a secondary circuit for the circulation of the shunt electric current. The main circuit comprises at least one first operating means, such as a switch - disconnector equipped with a fixed contact and a moving contact, while the secondary circuit comprises at least one second operating means, such as a vacuum switch comprising inside a fixed contact and a moving contact.
The switch of the invention can adopt at least three operating positions, making - breaking - disconnecting - grounding, so that the switch - disconnector can also comprise a grounding contact. In this way, the vacuum switch arranged in the secondary circuit performs the breaking operation and the switch - disconnector of the main circuit performs the making, disconnecting and grounding operations, thus compactly providing a load break or short-circuit currents switch capable of executing up to four operating positions.
In the opening sequence of the switch of the invention, the vacuum switch is actuated by the movement of the moving contact of the switch - disconnector through a control mechanism. The control mechanism comprises an electrically conductive tilting means, configured as at least one part made of conductive material, that is, this part conducts electricity on its entire external surface, and is attached to at least one lever through at least one first articulation element, such as a return spring. Said tilting means is mounted on a first free end of the lever and can tilt around the first articulation element in the opening sequence and/or in the closing sequence of the load break or short-circuit currents switch, that is, both in the opening run of the moving contact of the switch - disconnector and in the closing run of the moving contact of the switch - disconnector, only in the opening run of the moving contact of the switch - disconnector or only in the closing run of the moving contact of the switch - disconnector.
In the closing sequence of the switch of the invention, the tilting means does not interfere electrically or mechanically with the vacuum switch, and therefore neither with the secondary circuit. In other words, during the closing sequence there is a physical separation between the tilting means and the secondary circuit, with no electrical connection between them, thus avoiding the problem posed by the cited documents from the state of the art, relating to a possible current spark-over between the moving contact of the switch - disconnector and the secondary circuit, which would make the vacuum switch unable to withstand with its contacts closed and due to the separation of the contacts of the vacuum switch an arc would form between these separate contacts, which can cause a sudden increase in temperature and pressure that can lead to explosions that may cause material damage, the generation of toxic gases, and even personal injury. In the switch of the invention, this problem related to current spark-over is solved, since the moving contact of the switch - disconnector can be at least partially insulated and because the tilting means can rotate around the first articulation element or a first stop means can rotate around a third articulation element in a second direction (B) opposite to a first direction (A) until it is released from the moving contact of the switch - disconnector by sliding, without this having any electrical or mechanical effect on the secondary circuit or on the vacuum switch.
The first stop means of the control mechanism can be made of electrically conductive material wherein the tilting means may not be abutting in its rest position, so that the tilting means is not in electrical connection with the main circuit or with the secondary circuit, while in the opening sequence of the switch of the invention, the tilting means tilts around the first articulation element in the first direction (A) due to the thrust of the moving contact of the switch - disconnector until the tilting means abuts against the first stop means, such that said tilting means, the first stop means and the lever electrically and mechanically connect the moving contact of the vacuum switch with the moving contact of the switch - disconnector, with the first stop means and the moving contact of the vacuum switch being electrically connected by at least one electrically conductive means. At this moment the electrical current begins to circulate through the secondary circuit at the same time that it circulates through the main circuit. In the closing sequence of the switch of the invention, the tilting means rotates around the first articulation element in the second direction (B), opposite to direction (A), without electrically or mechanically connecting the moving contact of the vacuum switch with the moving contact of the switch - disconnector.
Both the lever and the first stop means can be made of insulating material or are insulated by another insulating material, so that in this case the tilting means is electrically connected to the moving contact of the vacuum switch by at least an electrically conductive medium. Therefore, in the opening sequence of the switch of the invention, as soon as the moving contact of the switch - disconnector intercepts the tilting means, the electrical current begins to circulate through the secondary circuit at the same time as it circulates through the main circuit. In the closing sequence of the switch of the invention, the first stop means can tilt around a third articulation element in the second direction (B) opposite to direction (A), without electrically or mechanically connecting the moving contact of the vacuum switch with the moving contact of the switch - disconnector. The first stop means can also comprise a protrusion where the moving contact of the switch - disconnector makes contact in the closing sequence of the switch of the invention.
On the contrary, the tilting means in its rest position can be abutting against the first stop means comprising the control mechanism and which may be mounted on the lever, said tilting means being in electrical and mechanical connection with the secondary circuit. In this sense, in the opening sequence of the switch - disconnector, its moving contact intercepts the tilting means during its opening run, at which moment the electric current begins to circulate through the secondary circuit at the same time that it circulates through the main circuit, since the moving contact of the vacuum switch and the moving contact of the switch - disconnector are electrically and mechanically connected through the tilting means and the lever, respectively. In this case, the tilting means is electrically connected to the moving contact of the vacuum switch by at least one electrically conductive means. In the event that the first stop means is electrically conductive, said first stop means is electrically connected to the moving contact of the vacuum switch by means of an electrically conductive means. In the closing sequence of the switch of the invention, the tilting means tilts around the first articulation element in the second direction (B), opposite to direction (A), without electrically or mechanically connecting the moving contact of the vacuum switch with the moving contact of the switch - disconnector.
In the state in which the electric current circulates both through the main circuit and through the secondary circuit, following the opening sequence, the moving contact of the switch - disconnector continues to push the tilting means and the latter pushes the lever. Due to the fact that the lever is also connected to a fixed part of the control mechanism by at least one second articulation element, such as a return spring that allows the lever to tilt, and to the moving contact of the vacuum switch by means of a mechanical connection point, the displacement of the lever due to the thrust of the tilting means causes the movement of the moving contact of the vacuum switch, thus starting the breaking operation. The moving contact of the switch - disconnector continues to push the tilting means and the latter pushes the lever, until the moving contact of the switch - disconnector releases the tilting means when the vacuum switch reaches its breaking position, thus interrupting the electrical current and extinguishing the electric arc.
The possibility that the tilting means may comprise a protrusion has been contemplated, so that both in the opening sequence and in the closing sequence of the switch of the invention, the moving contact of the switch - disconnector contacts said protrusion and pushes the tilting means.
Once the breaking operating position has been obtained, the tilting means separates from the moving contact of the switch - disconnector, and allows the vacuum switch to close its contacts, but without the passage of electric current since the secondary circuit remains open, leaving the vacuum switch ready for the next breaking operation and the entire branch of the secondary or shunt circuit at the same electrical potential while the switch - disconnector remains open. At this time, the disconnecting operating position has been obtained. From this point, the moving contact of the switch - disconnector would follow its opening sequence and by intercepting said moving contact the grounding contact would obtain the grounding position.
It has also been contemplated that the tilting means, instead of being a single part, may comprise two parts, a first part that can abut against the first stop means in an opening sequence of the switch of the invention and a second part which can tilt around the first articulation element in the closing sequence of the switch of the invention. Likewise, the first part of the tilting means can rest on a second stop means in its rest position, said first part and said second stop means being able to be connected by at least one flexible element, such as a return spring.
The switch - disconnector comprises an actuating shaft that acts on its moving contact to execute both the opening sequence and the closing sequence of the switch of the invention.
Lastly, the switch of the invention can be part of an electrical equipment and be integrated into said electrical equipment, such as a cell, which may comprise an enclosure in which the switch of the invention is integrated, immersed in a dielectric medium, at least one electrical connection element and one mechanical connection element accessible from the outside and inside of the enclosure, at least one cable compartment, one gas expansion compartment, as well as other electrical or electronic devices for measurement, control and protection , etc.

DESCRIPTION OF THE FIGURES

To complement the description and in order to help a better understanding of the features of the invention, according to several preferred examples of a practical embodiment thereof, a set of figures is attached as an integral part of said description in which, for illustrative and non-limiting purposes, the following has been represented:

Figure 1.- Shows a perspective view of the enclosure that incorporates inside immersed in a dielectric medium the switch of the invention, wherein at least one electrical connection element and one mechanical connection element have been represented accessible from the outside the enclosure.
Figure 2.- Shows an elevation view of the switch of the invention that incorporates at least part of its elements inside a housing.
Figure 3.- Shows an elevation view of the switch of the invention in its making operating position (the main electrical circuit is closed) according to a first embodiment of the invention, wherein the electrical current circulates only through the main circuit and wherein the housing of the load break or short-circuit currents switch or part of the lever of the control mechanism has not been represented for a better display.
Figure 4.- Shows an elevation view of the switch of the invention in its making operating position (the main electrical circuit is closed) according to a second embodiment of the invention, wherein the electrical current circulates only through the main circuit and wherein the housing of the load break or short-circuit currents switch or part of the lever of the control mechanism has not been represented for a better display.
Figure 5.- Shows an elevation view of the switch of the invention in its making operating position (the main electrical circuit is closed) according to a third embodiment of the invention, wherein the electrical current circulates only through the main circuit and wherein the housing of the load break or short-circuit currents switch or part of the lever of the control mechanism has not been represented for a better display.
Figure 6.- Shows an elevation view of the switch of the invention once the opening sequence has begun according to the embodiment of figure 3, wherein the electric current circulates both through the main circuit and through the secondary circuit.
Figure 7.- Shows an elevation view of the switch of the invention once the opening sequence has begun according to the embodiment of figure 4, wherein the electric current circulates both through the main circuit and through the secondary circuit.
Figure 8.- Shows an elevation view of the switch of the invention once the opening sequence has begun according to the embodiment of figure 5, wherein the electric current circulates both through the main circuit and through the secondary circuit.
Figure 9.- Shows an elevation view of the switch of the invention following the opening sequence according to the embodiment of figure 3, wherein the electric current only circulates through the shunt secondary circuit.
Figure 10.- Shows an elevation view of the switch of the invention following the opening sequence according to the embodiment of figure 4, wherein the electric current only circulates through the shunt secondary circuit.
Figure 11.- Shows an elevation view of the switch of the invention following the opening sequence according to the embodiment of figure 5, wherein the electric current only circulates through the shunt secondary circuit.
Figure 12.- Shows an elevation view of the switch of the invention following the opening sequence according to the embodiment of figure 3, in its breaking operating position.
Figure 13.- Shows an elevation view of the switch of the invention following the opening sequence according to the embodiment of figure 4, in its breaking operating position.
Figure 14.- Shows an elevation view of the switch of the invention following the opening sequence according to the embodiment of figure 5, in its breaking operating position.
Figure 15.- Shows an elevation view of the switch of the invention following the opening sequence according to the embodiment of figure 3, in its disconnecting operating position.
Figure 16.- Shows an elevation view of the switch of the invention following the opening sequence according to the embodiment of figure 4, in its disconnecting operating position.
Figure 17.- Shows an elevation view of the switch of the invention following the opening sequence according to the embodiment of figure 5, in its disconnecting operating position.
Figure 18.- Shows an elevation view of the switch of the invention according to the embodiment of figure 3, in its grounding operating position, wherein the housing of the load break or short-circuit currents switch or part of the lever of the control mechanism has not been represented for a better display.
Figure 19.- Shows an elevation view of the switch of the invention according to the embodiment of figure 4, in its grounding operating position.
Figure 20.- Shows an elevation view of the switch of the invention according to the embodiment of figure 5, in its grounding operating position.
Figures 21a - 21b.- Show respective details of the control mechanism that actuates the vacuum switch in the opening sequence of the switch of the invention according to the embodiment of figure 3.
Figures 22a - 22b.- Show respective details of the control mechanism that actuates the vacuum switch in the opening sequence of the switch of the invention according to the embodiment of figure 4, wherein the moving contact of the vacuum switch and the moving contact of the switch - disconnector are electrically connected through the tilting means and the first stop means, said first stop means being electrically connected with the moving contact of the vacuum switch through an electrically conductive means.
Figures 23a - 23b.- Show respective details of the control mechanism that actuates the vacuum switch in the opening sequence of the switch of the invention according to the embodiment of figure 4, wherein the moving contact of the vacuum switch and the moving contact of the switch - disconnector are electrically connected only through the tilting means, the tilting means being electrically connected to the moving contact of the vacuum switch through an electrically conductive means.
Figures 24a - 24b.- Show respective details of the control mechanism that actuates the vacuum switch in the opening sequence of the switch of the invention according to the embodiment of figure 5.
Figure 25.- Shows an elevation view of the switch of the invention in the closing sequence according to the embodiment of figure 3.
Figure 26.- Shows an elevation view of the switch of the invention in the closing sequence according to the embodiment of figure 4.
Figure 27.- Shows an elevation view of the switch of the invention in the closing sequence according to the embodiment of figure 5.
Figure 28.- Shows a perspective view of the electrical equipment that incorporates the switch of the present invention inside it.

PREFERRED EMBODIMENT OF THE INVENTION

Figure 1 shows an enclosure (28) inside which the load break or short-circuit currents switch (1) object of the present invention is installed, this enclosure (28) being able to be watertight, and insulated in any dielectric medium such as air, dry air, N₂, O₂, CO₂, or gas mixtures such as, for example, fluoroketones with vector gases such as CO₂, N₂, O₂, air or mixtures thereof, or gas mixtures such as, for example, hydrofluoroolefins with vector gases such as N₂, O₂, dry air, helium, CO₂ or mixtures thereof, or sulfur hexafluoride, etc.
The enclosure (28) comprises at least one electrical connection element (29), such as a male or female type bushing, and at least one mechanical connection element (32) accessible both from inside the enclosure (28) as well as from its outside, so that the coupling of other elements with the enclosure (28) is facilitated, such as a operating mechanism by means of mechanical connection elements (32) or other electrical switchgear by means of electrical connection elements (29). The load break or short-circuit currents switch (1) of the invention is installed inside said enclosure (28) and therefore isolated in the same dielectric medium that contains the enclosure (28).
As shown in figures 3-20, the load break or short-circuit currents switch (1) of the invention comprises a main circuit (2) for the circulation of the electric current and a secondary circuit (3) for the circulation of the shunt electric current. The main circuit (2) comprises at least a first operating means, such as a switch - disconnector (4), provided with a fixed contact (5) and a moving contact (6), while the secondary circuit (3) comprises at least one second operating means, such as a vacuum switch (7), which comprises inside a fixed contact (8) and a moving contact (9). The load break or short-circuit currents switch (1) of the invention can adopt at least three operating positions, making - breaking - disconnecting - grounding, so that the switch - disconnector (4) can also comprise a grounding contact (19). In this way, the vacuum switch (7) arranged in the secondary circuit (3) performs the breaking operation, as shown in figures 12-14, while the switch - disconnector (4) of the main circuit (2) performs the making, disconnecting and grounding operations, as shown in figures 3-5, 15-17 and 18-20 respectively.
Starting from the making operating position of the load break or short-circuit currents switch (1) of the invention represented in figures 3-5 and wherein the current only flows through the main circuit (2), in the opening sequence, the moving contact (6) of the switch - disconnector (4) intercepts, in the course of its opening run, a control mechanism (10), specifically with at least one tilting means (11) electrically conductive in its entire external contact surface that comprises said control mechanism (10). This tilting means (11) made of electrically conductive material may comprise at least one first protrusion (20), as shown in figures 3-27, in this case said first protrusion (20) being the one intercepted by the moving contact (6) of the switch - disconnector (4). The tilting means (11) is mounted on one end of at least one lever (12) made of insulating material through at least one first articulation element (13), such as a return spring.
According to a first embodiment of the invention, at the moment in which the moving contact (6) of the switch - disconnector (4) intersects with the tilting means (11) or with its first protrusion (20), it begins to push said tilting means (11) making it tilt around the first articulation element (13) in a first direction (A), without any current flowing through the secondary circuit (3), still current only flows through the main circuit (2). The moving contact (6) of the switch - disconnector (4) continues to push the tilting means (11), causing it to tilt in the first direction A, until the tilting means (11) abuts against a first stop means (14) that comprises the control mechanism (10) and which can be mounted on the lever (12), as can be seen in figure 6. At this very moment when the tilting means (11) abuts against the first stop means (14), the current begins to circulate through the secondary circuit (3) as well as through the main circuit (2), since up to this moment, the tilting means (11) in its rest position is not in contact with the first stop means (14). In this sense, the moving contact (9) of the vacuum switch (7) and the moving contact (6) of the switch - disconnector (4) are electrically connected through the tilting means (11) and the first stop means (14), being able to be electrically connected said first stop means (14) with the moving contact (9) of the vacuum switch (7) through at least one electrical conductive means (18), as shown in figures 21a -21b. Likewise, the moving contact (9) of the vacuum switch (7) and the moving contact (6) of the switch - disconnector (4) are mechanically connected through the tilting means (11), the first stop means (14) and of the lever (12). The first stop means (14) can be made of electrically conductive material, while the lever (12) can be made of insulating material or can be insulated by another insulating material.
In this first embodiment, the tilting means (11) can comprise two parts (21, 22), as shown in figures 21a-21b, a first part (21) that can abut against the first stop means (14) in an opening sequence of the load break or short-circuit currents switch (1) of the invention and a second part (22) that can tilt around the first articulation element (13) in the closing sequence of the load break or short-circuit currents switch (1) of the invention. Likewise, the first part (21) of the tilting means (11) can rest on a second stop means (25) in its rest position, said first part (21) and said second stop means (25) being able to be connected by means of at least one flexible element (26), such as a return spring.
According to a second embodiment of the invention, according to figure 4, in its rest position the tilting means (11) is in abutment with the first stop means (14), so that at the moment in which the moving contact (6) of the switch - disconnector (4) intercepts the tilting means (11) or its first protrusion (20) the current begins to circulate through the secondary circuit (3) as well as through the main circuit (2), as shown in figure 7. The moving contact (9) of the vacuum switch (7) and the moving contact (6) of the switch - disconnector (4) are electrically connected through the tilting means (11) and the first stop means (14), and said first stop means (14) being electrically connected with the moving contact (9) of the vacuum switch (7) through at least one electrically conductive means (18), as shown in figures 22a-22b. In this case, the first stop means (14) is made of electrically conductive material, while the lever (12) can be made of insulating material or can be insulated by another insulating material. Likewise, the possibility has been considered that the moving contact (9) of the vacuum switch (7) and the moving contact (6) of the switch - disconnector (4) are electrically connected only through the tilting means (11), the tilting means (11) being electrically connected to the moving contact (9) of the vacuum switch (7) through at least one electrically conductive means (18), as shown in figures 23a-23b. On the other hand, the moving contact (9) of the vacuum switch (7) and the moving contact (6) of the switch - disconnector (4) are mechanically connected through the tilting means (11), the first stop means (14) and the lever (12), as shown in figures 22a-22b and 23a-23b.
In a third possible embodiment of the invention, according to figure 5, in its rest position the tilting means (11) is not abutting against the first stop means (14) and the tilting means (11) is electrically connected to the moving contact (9) of the vacuum switch (7) through at least one electrically conductive means (18). Thus, at the moment in which the moving contact (6) of the switch - disconnector (4) intersects the tilting means (11) or its first protrusion (20), the current begins to circulate through the secondary circuit (3) at the same time than by the main circuit (2), as shown in figure 8. The moving contact (9) of the vacuum switch (7) and the moving contact (6) of the switch - disconnector (4) are electrically connected only through the tilting means (11), as shown in figures 24a-24b. Likewise, the moving contact (9) of the vacuum switch (7) and the moving contact (6) of the switch - disconnector (4) are mechanically connected through the tilting means (11) and the lever (12). The moving contact (6) of the switch - disconnector (4) continues to push the tilting means (11), causing it to tilt in the first direction (A), until the tilting means (11) abuts against a first stop means (14) that comprises the control mechanism (10) and which may be mounted on the lever (12).
Continuing with the opening sequence, the moving contact (6) of the switch - disconnector (4) separates from the fixed contact (5) and therefore from the main circuit (2) without producing any electric arc in the circuit and the current only circulates through the secondary circuit (3), as shown in figures 9-11. In turn, due to the thrust of the moving contact (6) of the switch - disconnector (4), the tilting means (11) pushes the first stop means (14) and this in turn pushes the lever (12). The lever (12) is connected to a fixed part (15) of the control mechanism (10) by means of a second articulation element (16), as shown in figures 2-27, around which the lever (12) tilts due to said thrust. Given that said lever (12) is also mechanically connected to the moving contact (9) of the vacuum switch (7) by means of at least one mechanical connection point (17), the tilting of the lever (12) causes the movement of the moving contact (9), thus beginning the separation between the contacts (8) and (9) of the vacuum switch (7). The moving contact (6) of the switch - disconnector (4) continues to push the tilting means (11) until the vacuum switch (7) reaches its breaking operating position, shown in figures 12-14, at which time the moving contact (6) of the switch - disconnector (4) releases the tilting means (11).
Once the breaking operating position has been obtained and the tilting means (11) of the moving contact (6) of the switch - disconnector (4) has been released, as shown in figures 15-17, it is possible to allow the vacuum switch (7) to close its contacts (8, 9), but without passage of electric current since the secondary circuit (3) remains open, and the lever (12) to return to its initial position by virtue of the action of the second articulation element (16), which can be, for example, a return spring. At this moment, the load break or short-circuit currents switch (1) of the invention is in the disconnecting operating position. The possibility has been considered that once the disconnecting operating position is obtained, the vacuum switch (7) does not close its contacts (8, 9), keeping them open until the closing sequence of the load break or short-circuit currents switch (1) of the invention.
From this point, the moving contact (6) of the switch - disconnector (4) can continue its opening sequence and when said moving contact (6) intercepts the grounding contact (19), the grounding position is obtained, as shown in figures 18-20.
In the closing sequence of the load break or short-circuit currents switch (1) of the invention, the tilting means (11) does not interfere electrically or mechanically with the vacuum switch (7), and therefore neither with the secondary circuit (3), because the moving contact (6) of the switch - disconnector (4) can be at least partially insulated by an insulating medium such as an insulating paint, an insulating cap, etc., and because the tilting means (11) can rotate around the first articulation element (13) in a second direction (B) opposite to direction (A) until it is released from the moving contact (6) of the switch - disconnector (4) by sliding, without this having any electrical or mechanical effect on the secondary circuit (3) or on the vacuum switch (7), that is, during the closing sequence there is a physical separation between the tilting means (11) and the secondary circuit (3), there being no mechanical or electric connection between both of them.
In the case of the first and second embodiments of the invention, according to figures 25 and 26, in the closing sequence the moving contact (6) of the switch - disconnector (4) contacts the first protrusion (20) and pushes the tilting means (11) making it tilt around the first articulation element (13) in the second direction (B) opposite to direction (A) until it is released by sliding. In the first embodiment, according to figure 25, specifically the first protrusion (20) is located in the second part (22) of the tilting means (11) and said second part (22) is the one that tilts around the first articulation element (13) in the second direction (B) until it is released by sliding.
In the case of the third embodiment of the invention, according to figure 27, in the closing sequence the moving contact (6) of the switch - disconnector (4) contacts a second protrusion (35) that comprises the first stop means (14) and pushes the first stop means (14) making it tilt around a third articulation element (34) in the second direction (B) opposite to direction (A) until it is released by sliding.
The switch - disconnector (4) comprises an actuating shaft (23), as shown in figures 2-20 and 25-27, which acts on the moving contact (6) to execute both the opening sequence and the closing sequence of the load break or short-circuit currents switch (1) of the invention due to the action of an operating mechanism not represented in the figures and which can be coupled to the enclosure (28) through the mechanical connection element (32) represented in figure 1.
The possibility has been considered that the load break or short-circuit currents switch (1) of the invention may comprise a housing (24), as shown in figure 2, wherein at least partially some of its elements are integrated, such as the moving contact (6) of the switch - disconnector (4), the control mechanism (10), the grounding contact (19) of the switch - disconnector (4), etc.
The load break or short-circuit currents switch (1) of the invention can comprise a three-phase configuration and therefore comprise part of its elements corresponding to the three phases, at least partially, incorporated inside the housing (24).
Finally, figure 28 shows electrical equipment (27), such as a cell, comprising at least one load break or short-circuit currents switch (1) of the invention in an enclosure (28) immersed in a dielectric medium, at least one electrical connection element (29) and a mechanical connection element (32) accessible from the outside and inside of the enclosure (28), at least one cable compartment (30), a gas expansion compartment (31), as well as other electrical or electronic devices (33) for measurement, control and protection, etc.

Claims

Load break or short-circuit currents switch (1) comprising a main circuit (2) for the circulation of the electric current and a secondary circuit (3) for the circulation of the shunt electric current, wherein the main circuit (2) comprises a switch - disconnector (4) provided with a fixed contact (5) and a moving contact (6), and wherein the secondary circuit (3) comprises a vacuum switch (7) which in turn comprises a fixed contact (8) and a moving contact (9), the vacuum switch (7) being activated by the movement of the moving contact (6) of the switch - disconnector (4) through a control mechanism (10), characterized in that the control mechanism (10) comprises an electrically conductive tilting means (11) connected to at least one lever (12), and in that at least the tilting means (11) and the lever (12) mechanically connect the moving contact (9) of the vacuum switch (7) with the moving contact (6) of the switch - disconnector (4) in the opening sequence of the load break or short-circuit currents switch (1).
Load break or short-circuit currents switch (1) according to claim 1, characterized in that the control mechanism (10) comprises a first stop means (14) wherein the tilting means (11) is not abutting in its rest position and wherein the tilting means (11) abuts in the opening sequence of the load break or short-circuit currents switch (1) due to the tilting of the tilting means (11) around a first articulation element (13).
Load break or short-circuit currents switch (1) according to claim 1, characterized in that the control mechanism (10) comprises a first stop means (14) wherein the tilting means (11) abuts in its rest position and wherein the tilting means (11) is not abutting in the closing sequence of the load break or short-circuit currents switch (1) due to the tilting of the tilting means (11) around a first articulation element (13).
Load break or short-circuit currents switch (1) according to any of the preceding claims, characterized in that the first stop means (14) is made of electrically conductive material and the lever (12) is made of insulating material or is insulated by another insulating material.
Load break or short-circuit currents switch (1) according to any of claims 1 to 3, characterized in that the first stop means (14) and the lever (12) are made of insulating material or are insulated by another insulating material.
Load break or short-circuit currents switch (1) according to claim 5, characterized in that the tilting means (11) is electrically connected to the moving contact (9) of the vacuum switch (7) by means of at least one electrically conductive means (18).
Load break or short-circuit currents switch (1) according to claim 4, characterized in that the first stop means (14) is electrically connected to the moving contact (9) of the vacuum switch (7) by means of at least one electrically conductive means (18).
Load break or short-circuit currents switch (1) according to any of the preceding claims, characterized in that the lever (12) is connected to a fixed part (15) of the control mechanism (10) by means of at least one second articulation element (16) that allows the lever (12) to tilt.
Load break or short-circuit currents switch (1) according to claim 8, characterized in that the lever (12) comprises a mechanical connection point (17) with the moving contact (9) of the vacuum switch (7).
Load break or short-circuit currents switch (1) according to any of the preceding claims, characterized in that it comprises a grounding contact (19).
Load break or short-circuit currents switch (1) according to claim 2, characterized in that the tilting means (11) comprises at least one first protrusion (20), so that in an opening sequence of the load break or short-circuit currents switch (1) the moving contact (6) of the switch - disconnector (4) contacts with said first protrusion (20) and pushes the tilting means (11) making it tilt around the first articulation element (13) in a first direction (A) until it hits the first stop means (14) and continues pushing it until it is released when the vacuum switch (7) reaches its breaking operating position, while in a closing sequence of the load break or short-circuit currents switch (1) the moving contact (6) of the switch - disconnector (4) makes contact with said first protrusion (20) and pushes the tilting means (11) causing it to tilt around the first articulation element (13) in a second direction (B) opposite to direction (A) until it is released by sliding.
Load break or short-circuit currents switch (1) according to claim 3, characterized in that the tilting means (11) comprises at least one first protrusion (20), so that in an opening sequence of the load break or short-circuit currents switch (1) the moving contact (6) of the switch - disconnector (4) contacts said first protrusion (20) and pushes the tilting means (11) that is abutting against the first stop means (14) and in turn the lever (12), releasing the tilting means (11) when the vacuum switch (7) reaches its breaking operating position, while in a closing sequence of the load break or short-circuit currents switch (1) the moving contact (6) of the switch - disconnector (4) makes contact with said first protrusion (20) and pushes the tilting means (11) making it tilt around the first articulation element (13) in a second direction (B) opposite to a first direction (A) until it is released by sliding.
Load break or short-circuit currents switch (1) according to claim 12, characterized in that the moving contact (6) of the switch - disconnector (4) is partially insulated by an insulating medium.
Load break or short-circuit currents switch (1) according to claim 5, characterized in that the first stop means (14) is mounted on one end of the lever (12) through a third articulation element (34), so that in an opening sequence of the load break or short-circuit currents switch (1) the moving contact (6) of the switch - disconnector (4) contacts a first protrusion (20) of the tilting means (11) and pushes the tilting means (11) making it tilt around the first articulation element (13) in a first direction (A) until it hits the first stop means (14) and continues to push it until it is released when the vacuum switch (7) reaches its breaking operating position, while in a closing sequence of the load break or short-circuit currents switch (1) the moving contact (6) of the switch - disconnector (4) contacts a second protrusion (35) of the first stop means (14) and pushes said first stop means (14) making it tilt around the third articulation element (34) in a second direction (B) opposite to direction (A) until it is released by sliding.
Load break or short-circuit currents switch (1) according to claim 11, characterized in that the tilting means (11) comprises two parts (21, 22), a first part (21) that abuts against the first stop means (14) in an opening sequence of the load break or short-circuit currents switch (1) and a second part (22) that pivots around the first articulation element (13) in the closing sequence of the load break or short-circuit currents switch (1).
Load break or short-circuit currents switch (1) according to claim 15, characterized in that the first part (21) of the tilting means (11) rests on a second stop means (25), said first part (21) and said second stop means (25) being connected by a flexible element (26).
Load break or short-circuit currents switch (1) according to any of the preceding claims, characterized in that the first articulation element (13), the second articulation element (16), the third articulation element (34) and the flexible element (26) comprise return springs.
Load break or short-circuit currents switch (1) according to any of the preceding claims, characterized in that the switch - disconnector (4) comprises an actuating shaft (23) that acts on the moving contact (6) of the switch - disconnector (4).
Load break or short-circuit currents switch (1) according to any of the preceding claims, characterized in that it comprises a housing (24).
Load break or short-circuit currents switch (1) according to any of the preceding claims, characterized in that it comprises a three-phase configuration.
Electrical equipment (27) comprising at least one load break or short-circuit currents switch (1) as described in any of the preceding claims, which also comprises an enclosure (28) wherein the load break or short-circuit currents switch (1) immersed in a dielectric medium is integrated, at least one electrical connection element (29) and a mechanical connection element (32) accessible from outside the enclosure (28), at least one cable compartment (30 ), a gas expansion compartment (31), as well as other electrical or electronic devices (33).