EP3599630B1 - Electrical device for vehicle and associated vehicle - Google Patents

Description

The present invention relates to an electrical device for a vehicle, in particular for a rail vehicle, the electrical device comprising a high voltage enclosure, the high voltage enclosure comprising an electrical switch, an actuator and a drive member connecting the switch to the actuator. .

Such a device is for example an electric circuit breaker. In this case, the device is placed in an electrical circuit for supplying electricity to a railway vehicle in order to protect said electrical supply circuit in the event of a short circuit.

We know from the document CN 104330733 a high voltage circuit breaker disposed in part on the roof of a vehicle and extending through an opening made in said roof. This circuit breaker comprises an epoxy material casing, a vacuum interrupter inside which extend a first electrical contact and a second electrical contact movable relative to the first electrical contact, each electrical contact being connected to connectors having high potentials. , typically potentials greater than 5 kV. Such a device is also known from the document FR 2 925 755 A1 .

However, such a device is not entirely satisfactory and is in particular liable to give rise to a risk of internal ignition of an electric arc.

An object of the invention is to provide an electrical device limiting the risk of malfunction.

To this end, the invention relates to an electrical device of the aforementioned type according to claim 1.

The electrical device according to the invention makes it possible, through said screen, to oppose the creation and propagation of a possible electric arc outside the enclosure. The screen also makes it possible to limit the diffusion, in the direction of electrically live parts, of humidity and dust present outside the device. The electrical device is therefore safer, and its service life is further extended.

• l'organe d'entrainement est mobile par rapport à l'écran ;
• la distance entre l'écran et l'organe d'entrainement est supérieure ou égale à 0,5 mm ;
• l'écran est flexible ;
• l'écran est réalisé en un matériau polymérique, le matériau polymérique comprenant au moins un élastomère, tel qu'une silicone ;
• l'écran présente une épaisseur supérieure ou égale à 2 mm, l'organe d'entrainement s'étendant selon un axe d'extension, l'épaisseur de l'écran étant mesurée selon ledit axe d'extension ;
• l'écran est fixé à l'enceinte.

According to other advantageous aspects of the invention, the device comprises one or more of the following characteristics, taken in isolation or in any technically possible combination:

• the drive member is movable relative to the screen;
• the distance between the screen and the drive member is greater than or equal to 0.5 mm;
• the screen is flexible;
• the screen is made of a polymeric material, the polymeric material comprising at least one elastomer, such as a silicone;
• the screen has a thickness greater than or equal to 2 mm, the drive member extending along an axis of extension, the thickness of the screen being measured along said axis of extension;
• the screen is attached to the speaker.

The subject of the invention is also a vehicle, in particular a railway vehicle, comprising an electrical device as defined above.

• la figure 1 est une vue schématique en coupe d'un dispositif électrique selon l'invention, le dispositif comprenant une enceinte haute tension à l'intérieur de laquelle s'est formé un arc électrique, le dispositif comprenant en outre un écran disposé à l'écart d'un organe d'entrainement ;
• la figure 2 est une vue schématique en coupe d'une partie d'un dispositif électrique analogue au dispositif de la figure 1, dans lequel l'écran est en contact avec l'organe d'entrainement ; et
• la figure 3 est une vue analogue à celle de la figure 2, l'écran présentant une épaisseur non constante.

Other aspects and advantages of the invention will become apparent on reading the description which follows, given solely by way of example, and made with reference to the appended drawings, in which:

• the figure 1 is a schematic sectional view of an electrical device according to the invention, the device comprising a high voltage enclosure inside which an electric arc has formed, the device further comprising a screen disposed away from 'a training body;
• the figure 2 is a schematic sectional view of part of an electrical device similar to the device of the figure 1 , wherein the screen is in contact with the drive member; and
• the figure 3 is a view similar to that of the figure 2 , the screen having a non-constant thickness.

In the remainder of the description, the expression “substantially equal to” defines a relation of equality at plus or minus 20%, preferably at plus or minus 10%.

For the purposes of the invention, the term “high voltage” is understood to mean an electric voltage substantially greater than or equal to 5 kilovolts (5 kV).

On the figure 1 , an electrical device 10 is intended to be mounted above or inside a railway vehicle (not shown), in particular a train, a tram, a metro or the like. Conventionally, the rail vehicle comprises in particular a roof, a pantograph and a high voltage electrical network. The electrical device 10 is for example intended to be mounted on the roof of the rail vehicle.

The electrical device 10 is for example a circuit breaker, a switch, a contactor, or any other device configured to allow the circulation of an electric current having a voltage greater than or equal to 5 kV. The current is in particular able to flow via bare live parts.

With reference to the figure 1 , the device 10 comprises a high voltage enclosure 12, an actuator 14, a drive member 16 and a screen 18. The term “screen” means within the meaning of the present invention a separation wall or a separation membrane. Preferably, the electrical device 10 further comprises a support 19.

The high voltage enclosure 12 is configured to allow the flow of an electric current having a voltage greater than or equal to 5 kV.

The enclosure 12 is likely to have different shapes depending on the nature of the electrical device 10. For example, the enclosure 12 has the shape of a rectangular parallelepiped. As a variant, the enclosure 12 has a symmetry of revolution about a longitudinal axis.

In the example of figure 1 , the enclosure 12 has a substantially cylindrical shape extending along a longitudinal axis A.

The enclosure 12 defines a central cavity 20 delimited by an outer wall 22. The enclosure 12 has at least one opening 24. In the example of figure 1 , the enclosure 12 has a first opening 24 oriented towards the actuator 14. The first opening 24 is preferably placed near the actuator 14, for example at a distance of less than 5 cm from the actuator 14.

Advantageously, the outer wall 22 has a plurality of circumferential annular fins 26 extending radially outwardly from the device 10. The fins 26 are substantially parallel to one another. The fins 26 reduce the risk of creating and propagating an electric arc on the surface of the outer wall 22 of the enclosure 12.

The enclosure 12 is made of an insulating material. Advantageously, the enclosure 12 is devoid of metallic material so as to ensure no electrical conduction. Preferably, the enclosure 12 is made of a polymeric material. The polymeric material preferably comprises at least one epoxy polymer, also known under the name of “polyepoxide” or of “epoxy polymer”. As a variant, the enclosure 12 is made of a ceramic material.

On the figure 1 , an electric arc 27 is shown propagating inside the enclosure 12.

The enclosure 12 comprises an electrical switch 30, arranged in the enclosure 12.

The electrical switch 30 comprises a first electrical contact 32, a second electrical contact 34 and a bulb 36 within which extend the first electrical contact 32 and the second electrical contact 34.

For example, the switch 30 is a vacuum interrupter, the bulb 36 then being a vacuum interrupter. As known per se, the use of a vacuum interrupter 30 allows to switch currents and to isolate a circuit under a high voltage with short inter-contact distances, the vacuum playing the role of electrical insulator.

The first contact 32 is fixed relative to the bulb 36. The second electrical contact 34 is movable between a closed position (or closed position) of the switch 30 in which the second contact 34 bears against the first contact 32. (as shown on figure 1 ) and an open position (or open position) of the switch 30 in which the second contact 34 is away from the first contact 32.

The electrical contacts 32, 34 are electrically connected to a respective electrical connection terminal 38, 40, each connection terminal 38, 40 being disposed outside the bulb 36. For example, the second electrical contact 34 is connected to its respective connection terminal 40 by means of a braid 42.

As known per se, the connection terminals 38, 40 are able to be electrically connected together in the closed position of the switch 30, the electrical contacts 32, 34 then being pressed against each other, and are capable of being electrically isolated from one another in the open position of the switch 30, the electrical contacts 32, 34 then being away from one another. The connection terminals 38, 40 are suitable for withstanding electrical voltages greater than 5 kV. The connection terminals 38, 40 are for example connected to a pantograph or to the electrical network of the railway vehicle.

The drive member 16 is arranged outside the switch 30 and extends along an axis of extension. In the example of figure 1 , said axis of extension coincides with the longitudinal axis A of the enclosure 12. The drive member 16 extends through the opening of the enclosure 12.

The drive member 16 has a first end 50 and a second end 52 opposite the first end 50 along the axis of extension of the drive member 16. The drive member 16 is fixed to the second contact 34 movable at its first end 50 and is fixed to the actuator 14 at its second end 52. The fixing of the drive member 16 at its second end 52 to the actuator 14 is a direct or even indirect fixing via an angle transmission or a reduction gear.

The drive member 16 connects the switch 30 to the actuator 14. The drive member 16 allows the movement of the second electrical contact 34 between the closed position and the open position of the switch 30.

In the example of figure 1 , the drive member 16 has the shape of a rod 54. The rod 54 has a radial section, said section having for example the shape of a circle, an ellipse or a polygon, in particular of a rectangle.

The drive member 16 provides electrical insulation between the second electrical contact 34 and the actuator 14. The drive member 16 is made, for example, of laminated material based on glass fibers.

Advantageously, and as shown in figure 1 , the drive member 16 comprises at least one fin 56 projecting radially with respect to the rod 54. The fin (s) 56 limit (s) the risk of propagation of a respective electric arc 27 on the surface of the drive member 16.

The drive member 16 comprises at least one return member (not shown) arranged to exert on the second electrical contact 34 a return force from the closed position of the switch 30 to the open position of the switch. switch 30. The return member is for example a spring.

The actuator 14 acts against the return member. The actuator 14 is arranged to exert a force opposite to the force exerted by the return member while maintaining the second electrical contact 34 in the closed position. In the example of figure 1 , the actuator 14 is an electromagnet.

The actuator 14 is arranged on a support. For example, the actuator 14 is placed inside a box 58.

The actuator 14 is configured to cause the movement of the drive member 16 and thus the movement of the second electrical contact 34 between the open position and the closed position. The actuator 14 thus controls the passage of current inside the electrical switch 30.

The screen 18 is placed between the high voltage enclosure 12 and the actuator 14, so that the enclosure 12 and the actuator 14 are arranged on either side of said screen 18. The screen 18 is preferably fixed. to the enclosure 12, for example by means of a screwing and / or clamping member (not shown). As a variant, the screen 18 is glued to the enclosure 12.

As shown on figure 1 , the cavity 20 of the enclosure 12 is partly delimited by the screen 18. The screen 18 partially closes the first opening 24 at one end of the enclosure 12 along the axis of extension.

The screen 18 has a thickness E greater than or equal to 2 mm, the thickness E of the screen 18 being measured along the axis of extension of the drive member 16. In the example of figures 1 and 2 , the thickness E of the screen 18 is substantially constant.

Alternatively, on the figure 3 , the screen 18 has a non-constant thickness E.

The screen 18 is made of a polymeric material. Preferably, the polymeric material comprises at least one elastomer, advantageously at least one silicone, also called polysiloxane.

The screen 18 has a recess 62 through which extends the driving member 16. The distance D between the screen 18 and the driving member 16 is less than 3 mm, preferably less than 2 mm. .

This distance D limits the risk of creation or propagation of an electric arc 27 formed in the enclosure 12 towards the outside of said enclosure 12. This distance D also limits the diffusion of humidity present in the air, from the outside of the enclosure 12 towards the inside of the enclosure 12. Thus, the inside of the enclosure 12 has a lower humidity level than the humidity level near the actuator 14 The screen 18 acts as an anti-humidity and anti-electric arc barrier.

The drive member 16 is movable relative to the screen 18.

As shown on figure 1 , the screen 18 is disposed away from the driving member 16. The distance D between the screen 18 and the driving member 16 is greater than or equal to 0.5 mm.

As a variant, on figures 2 and 3 , the screen 18 rests against the driving member 16. In the example of figure 3 , the edge 61 bears against the driving member 16. The frictional forces between the screen 18 and the driving member 16 are low enough to allow the movement of the driving member 16 between the closed position and the open position.

As a variant, the screen 18 is fixed to the drive member 16, for example by gluing. According to this variant, the screen 18 is capable of breaking in the event of a pressure greater than 0.2 MPa (2 bars).

Advantageously, the screen 18 is flexible. The term “flexible” is understood to mean that the screen 18 is capable of deforming under the effect of a pressure greater than 0.2 MPa (2 bars), called the critical pressure Pc.

The screen 18 is able to deform between a rest configuration, shown in solid lines on the figure 1 , and a distorted configuration, shown in dotted lines on the figure 1 .

In the rest configuration, the screen 18 extends substantially along a plane normal to the axis of extension of the drive member 16 and the recess 62 has a minimum area, called A _rest .

In the deformed configuration, the screen 18 has a curved surface, and the recess 62 has an area greater than the minimum area A at _rest .

In the event of an overpressure within the enclosure 12, due for example to an electric arc 27 (also called “ flashover” in English), the screen 18 is able to deform, limiting the risk of degradation of the electrical device 10, up to perforation of the enclosure 12.

It will be understood that it is possible to choose the nature and / or the thickness E of the screen 18 as a function of the electrical device 10, of the voltages involved or of the pressure capable of being supported by the enclosure 12.

In the example of figure 1 , the enclosure 12 is arranged on the support 19 and extends in a direction substantially perpendicular to the plane of said support 19. The screen 18 is arranged between the enclosure 12 and the support 19.

For example, the support 19 is formed by at least part of the roof of the rail vehicle. As a variant, the support 19 is formed of a plate fixed to at least part of the roof of the rail vehicle.

The support 19 has an opening 72 through which extends the drive member 16, so that the switch 30 and the actuator 14 are arranged on either side of the support 19.

The operation of the electrical device 10 according to the invention will now be described.

When using the electrical device 10, a high voltage electric current flows through the conductive parts of the enclosure 12. The screen 18 is then in the idle configuration.

When an electric arc 27 forms inside the enclosure 12, the screen 18 forms, at least temporarily, an obstacle to the propagation of said electric arc 27 outside the enclosure 12.

The electric arc 27 causes an increase in the pressure inside the enclosure 12. When the pressure is less than the critical pressure Pc, the screen 18 does not deform and remains in the rest configuration.

When the pressure inside the enclosure 12 is greater than or equal to the critical pressure Pc, the screen 18 is deformed to a deformed configuration shown in dotted lines on the diagram. figure 1 . This makes it possible to reduce the pressure inside the enclosure 12 and to distribute it in the box 58.

The screen 18 makes it possible on the one hand to hinder, or even prevent, the creation of a possible electric arc 27 towards the outside of the enclosure 12 and, on the other hand, to limit the diffusion of humidity. present outside the device 10 to the electric switch 30.

In addition, in the case where the electric arc 27 is sufficiently strong and risks damaging the device 10, or even causing the degradation of the enclosure 12, the screen 18 is deformed, thus preventing too great an overpressure. inside the device 10. The correct operation of the electrical device 10 is thus reinforced.

It will then be understood that the electrical device 10 according to the invention is safer and has a longer lifespan than the device of the state of the art.

Claims (7)

1. Electrical device (10) for a vehicle, in particular for a rail vehicle, the electrical device (10) comprising:

   - a high-voltage enclosure (12), the high-voltage enclosure (12) including an electrical switch (30);

   - an actuator (14); and

   - a drive member (16) connecting the switch (30) to the actuator (14);

   the electrical device (10) further comprises a screen (18) arranged between the enclosure (12) and the actuator (14), the screen (18) having a recess (62) through which the drive member (16) extends, the distance (D) between the screen (18) and the drive member (16) being less than 3 mm, preferably less than 2 mm,
   characterised in that the screen (18) is flexible and capable of being deformed under the effect of a pressure greater than 0.2 MPa.
2. Device (10) according to claim 1, wherein the drive member (16) is movable relative to the screen (18).
3. Device (10) according to either claim 1 or claim 2, wherein the distance (D) between the screen (18) and the drive member (16) is greater than or equal to 0.5 mm.
4. Device (10) according to any of claims 1 to 3, wherein the screen (18) is made of a polymeric material, the polymeric material comprising at least one elastomer, such as a silicone.
5. Device (10) according to any of claims 1 to 4, wherein the screen (18) has a thickness (E) greater than or equal to 2 mm, the drive member (16) extending along an axis of extension, and the thickness (E) of the screen (18) being measured along said axis of extension.
6. Device (10) according to any of claims 1 to 5, wherein the screen (18) is secured to the enclosure (12).
7. Vehicle, in particular a rail vehicle, comprising an electrical device (10) according to any of claims 1 to 6.

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