SWITCH HAVING AN ARC-QUENCHING DEVICE

Abstract

A switching device in a vacuum switching tube or for arc quenching in gases. The switching device has an arc-quenching device. There is also described a method for operating a switching device in a vacuum switching tube or in arc quenching in gases, which switching device has an arc-quenching device for medium-voltage, low-voltage and/or high-voltage applications.

Claims

1-13. (canceled)

14. A switching device for application in a vacuum switching tube or for arc quenching in gases, the switching device comprising: a contact system having a moveable contact electrically conductively connected to a first electrical contact and a fixed contact electrically conductively connected to a second electrical contact; an arc-quenching device having: an arrangement for generating a magnetic field which is constituted in a perpendicular plane to a direction of motion of said moveable contact, wherein said arrangement for generating the magnetic field including a U-shaped core having a base arranged between said fixed contact and an electrical connecting lead of said fixed contact which constitutes a first current loop, wherein said connecting lead connects said fixed contact to said second electrical contact in an electrically conductive manner, and said U-shaped core having two limbs that extend along said contact system, around said contact system; two or more arc-quenching electrodes laterally offset from said contact system such that a movement of said moveable contact of said contact system is not restricted by said two or more arc-quenching electrodes; said two or more arc-quenching electrodes, when said contact system is in an open state, being laterally offset between said moveable contact and said fixed contact; said two or more arc-quenching electrodes being arranged perpendicularly to the direction of motion of said moveable contact; and said two or more arc-quenching electrodes being arranged on an open side of said U-shaped core of said arrangement for generating the magnetic field, such that a Lorentz force can act on moving electrons in a plasma of an arc in the magnetic field of said arrangement for generating the magnetic field; an electrical counter-pulse device having at least one first capacitor and/or having at least one transformer, wherein said electrical counter-pulse device: is connected to said first electrical contact and to said second electrical contact; and is connected to said two or more arc-quenching electrodes such that a first arc-quenching electrode of said two or more arc-quenching electrodes, in the open state of said contact system, is arranged in closer spatial proximity to said fixed contact than to said moveable contact, and such that said first capacitor and/or said at least one transformer, on a first side, is connected to said first arc-quenching electrode, wherein the first side assumes a polarity of said first electrical contact; and is connected to said two or more arc-quenching electrodes, such that a second arc-quenching electrode of said two or more arc-quenching electrodes, in the open state of said contact system, is arranged in closer spatial proximity to said moveable contact than to said fixed contact, and such that said first capacitor and/or said at least one transformer (46), on a second side, is connected to said second arc-quenching electrode, wherein the second side assumes a polarity of said second electrical contact.

15. The switching device according to claim 14, wherein said electrical counter-pulse device comprises a first capacitor or said electrical counter-pulse device comprises a first capacitor, a second capacitor and a third capacitor, and wherein said first capacitor, said second capacitor and said third capacitor are connected in series.

16. The switching device according to claim 15, wherein: said electrical counter-pulse device comprises at least one parallel circuit comprised of said first capacitor and said transformer, wherein said first capacitor is connected to two or more of said arc-quenching electrodes in an electrically conductive manner; or said electrical counter-pulse device is comprised only of said at least one transformer, wherein said at least one transformer is connected to two or more of said arc-quenching electrodes in an electrically conductive manner.

17. The switching device according to claim 14, wherein: said moveable contact is bonded by way of a second current loop, which is angled through 90; and said moveable contact, with at least part of said 90-angled second current loop, is arranged in said U-shaped core of said arrangement such that, upon opening the energized contact system, a second force acts on said moveable contact that is oriented in the direction of the opening moveable contact.

18. The switching device according to claim 17, wherein an opening of said contact system is executed exclusively by the second force.

19. The switching device according to claim 17, wherein an opening of said contact system is executed by an external force, which is transmitted from an exterior of said arc-quenching device to said moveable contact, and by the second force.

20. The switching device according to claim 14, configured for medium-voltage, low-voltage and/or high-voltage applications.

21. The switching device according to claim 14, configured as a switching device for direct current.

22. The switching device according to claim 14, configured as a switching device for alternating current.

23. The switching device according to claim 14, configured as a switching device for current limiting.

24. The switching device according to claim 14, further comprising a sliding contact and/or a flexible conductor connecting said moveable contact of said contact system to said first electrical contact.

25. A method of operating a switching device according to claim 14, the method comprising: providing an arc-quenching device with an arrangement for generating a magnetic field which is constituted in a perpendicular plane to the direction of motion of a moveable contact in a contact system; moving an arc that is generated upon the opening of the contact system by means of the arc-quenching device towards two or more arc-quenching electrodes of the arc-quenching device; and thus discharging the electrical counter-pulse device such that, via the arc-quenching electrodes, a counter-pulse which counteracts the arcing current is introduced into the contact system, to thereby quench the arc in the arc quenching device.

26. The method according to claim 25, wherein the counter-pulse of the electrical counter-pulse device is an electric voltage or an electric current.

Description

[0043] The invention is described hereinafter on the basis of two figures and one exemplary embodiment, with reference to the attached figures.

[0044] FIG. 1: shows a schematic view of an exemplary embodiment of a switching device with an open contact system.

[0045] FIG. 2: shows a schematic view of an exemplary embodiment of a switching device with an open contact system, having alternative electrical counter-pulse devices.

[0046] FIG. 1 shows a schematic view of the switching device 1 with an open contact system 4. The contact system 4 is comprised of a fixed contact 5 and a moveable contact 7. The contact system 4 and an arrangement 13 for the generation of a magnetic field 42 of an arc-quenching device are arranged in a vacuum tube 10, only an indication of which is included in FIG. 1.

[0047] The moveable contact 7 is connected via a second conductor loop 6 and a sliding contact 9 to a first electrical contact 2. In this case, the moveable contact 7 is guided, for example, in a bearing 11. A vacuum-tight connection of the moveable contact 7 to a vacuum tube can be achieved by means of a bellows, folding bellows or corrugated bellowswhich are not represented here. This arrangement can also be operated in gases, which is not represented. The fixed contact 5 is connected via the first current loop 6 to a second electrical contact 3.

[0048] The contact system 4 is arranged in an arc-quenching device, which incorporates an arrangement 13 for generating a magnetic field 42. The arrangement 13 comprises a U-shaped core 14 having a base 15, a first limb 19 and a second limb 20. The limbs 19, 20 enclose two sides of the U-shaped core, whereas two further sides are open. The region of the U-shaped core 14 arranged opposite the base 15 is likewise open.

[0049] The first arc-quenching electrode 34 and the second arc-quenching electrode 36 are arranged with a lateral offset from the contact system 4, such that the moveable contact 7 of the contact system 4, in its movement, is not restricted by the two arc-quenching electrodes 34, 36. In the open state of the contact system 4, the two arc-quenching electrodes 34, 36 are laterally offset between the moveable contact 7 and the fixed contact 5. The two arc-quenching electrodes 34, 36 are situated on one of the open sides of the U-shaped core 14, specifically on the open side of the U-shaped core 14 upon which a Lorentz force 38 acts on the moving electrons in the plasma of the arc 22 in the magnetic field 42 of the arrangement 13.

[0050] In FIG. 1, the arc-quenching electrodes incorporate U-shaped insulating jackets 59.

[0051] FIG. 1 represents a situation in which the first electrical contact 2 lies at a negative potential, and the second electrical contact 3 lies at a positive potential. In the event of an inverse polarity, the device operates in an analogous manner, such that both alternating currents and direct currents can be switched. As a result of the current which flows in response to the potential difference, an arc 22 is generated upon the opening of the contact system 4, in the plasma of which electrons move from the moveable contact 7 to the fixed contact 5. As a result of the magnetic field 42 generated by the arrangement 13, the electrons in the plasma of the arc 22 move in the direction of the arc-quenching electrodes 34, 36. As a result, the arc sparks over to the arc-quenching electrodes 36, 34. The arc-quenching device further comprises an electrical counter-pulse device 44 having at least one first capacitor 46. In the exemplary embodiment represented in FIG. 1, the electrical counter-pulse device 44 incorporates a capacitor 46, a second capacitor 45, and a third capacitor 47.

[0052] The electrical counter-pulse device 44 is connected to the first electrical contact 2 and to the second electrical contact 3.

[0053] The first arc-quenching electrode 34 which, in the open state of the contact system 4, is arranged in closer spatial proximity to the fixed contact 5 than to the moveable contact 7, is electrically connected to the side of the first capacitor 46 which carries the polarity of the first electrical contact 2.

[0054] The second arc-quenching electrode 36 which, in the open state of the contact system 4, is arranged in closer spatial proximity to the moveable contact 7 than to the fixed contact 5, is connected to the side of the first capacitor 46 which carries the polarity of the second electrical contact 3.

[0055] By means of this arrangement, and the electrical connection of the arc-quenching electrodes 34, 36, in the event of the spark-over of an arc from one contact (in this case, the moveable contact 7) via the arc-quenching electrodes 36, 34 to the other contact (in this case, the fixed contact 5), a counter-current is injected from the capacitor 46 into the arc-quenching device. This results in the quenching of the arc 22.

[0056] Additionally, by means of the second conductor loop 6 which is angled through 90, the current flowing in said conductor loop 6 and the magnetic field 42 generated by the arrangement 13 exert a force on the moveable contact, which results in the opening of the contact system 4, or in the accelerated opening of the contact system 4.

[0057] FIG. 2 represents the exemplary embodiment of the switching device 1 according to FIG. 1, and additionally shows two alternative embodiments of the electrical counter-pulse device 44, having a transformer 46 or a transformer 46 and a first capacitor 46.

[0058] FIG. 2, analogously to FIG. 1, shows the design of the contact system 4, having the moveable contact 7 and the fixed contact 5. The fixed contact 5 is electrically connected via a first current loop 6 to a second electrical contact 3. The moveable contact 7 is electrically connected via a second contact loop 6 and the sliding contact 9 to the first contact 2.

[0059] The moveable contact is moveably mounted in the bearing 11, and can move in the direction of motion 12.

[0060] The arrangement 13 having the U-shaped core 14, the base 15, the first limb 19 and the second limb 20 is employed for the generation of a magnetic field 42 which, in the event of the occurrence of an arc 22 in the contact system 4, in combination with the movement of electrons in the plasma of the arc 22, exerts a Lorentz force 38.

[0061] By the action of the Lorentz force 38, the arc is moved onto the arcing path 22 via the arc-quenching electrodes 34, 36. In the event of the spark-over of the arc 22 to the arc-quenching electrodes 34, 36, a counter-pulse is applied to the arc-quenching electrodes 34, 36 by the electrical counter-pulse device 44, such that the arc 22 on the arcing path 22 is quenched.

[0062] The force 58 resulting from the magnetic field 42 and the current 60 in the conductor loop 6 and acting on the moveable contact 7 is represented in an analogous manner to FIG. 1.

[0063] The arc-quenching electrodes 34, 36 in FIG. 2 again incorporate optional U-shaped insulating jackets 59.

[0064] The arc-quenching electrodes 34, 36 additionally incorporate optional surface area enlargements, and thus respectively constitute a first arc-quenching electrode having a surface area enlargement 34, and a second arc-quenching electrode having a surface area enlargement 36.

[0065] In addition to the electrical counter-pulse device 44 in FIG. 1, having the first capacitor 46, the second capacitor 45 and the third capacitor 47, FIG. 2 also shows two alternative electrical counter-pulse devices 44. However, only one variant of the electrical counter-pulse device 44 is employed.

[0066] The first alternative electrical counter-pulse device 44 comprises a transformer 46 and a first capacitor 46 which is parallel-connected to the transformer 46. In an analogous manner to FIG. 1, the capacitor 46 is connected to the arc-quenching electrodes 34, 36 such that, in the event of an arc 22, said arc 22 is quenched on the arcing path 22 by a counter-pulse from the electrical counter-pulse device 44.

[0067] The second alternative electrical counter-pulse device 44 comprises a transformer 46. In an analogous manner to the capacitor 46 in FIG. 1, the transformer 46 is connected to the arc-quenching electrodes 34, 36 such that, in the event of an arc 22, said arc 22 is quenched on the arcing path 22 by a counter-pulse from the electrical counter-pulse device 44.

[0068] The option for the provision of one or more further capacitors up-circuit and down-circuit of a transformer 46 is not represented or described in further detail.

LIST OF REFERENCE NUMBERS

[0069] 1 Switching device [0070] 2 First electrical contact [0071] 3 Second electrical contact [0072] 4 Contact system [0073] 5 Fixed contact of the contact system [0074] 6 First current loop for the generation of the magnetic field with the arrangement 13 [0075] 6 Second current loop for the generation of a force 58 on the moveable contact 7 [0076] 7 Moveable contact of the contact system [0077] 9 Sliding contact [0078] 10 Vacuum tube [0079] 11 Bearing [0080] 12 Direction of motion [0081] 13 Arrangement [0082] 14 U-shaped core [0083] 15 Base [0084] 19 First limb [0085] 20 Second limb [0086] 22 Arc [0087] 34 First arc-quenching electrode [0088] 34 First arc-quenching electrode with surface area enlargement [0089] 36 Second arc-quenching electrode [0090] 36 Second arc-quenching electrode with surface area enlargement [0091] 38 Lorentz force resulting from the magnetic field 42 and the movement of the electrons [0092] 42 Magnetic field and orientation of magnetic field constituted by the arrangement 13 [0093] 44 Electrical counter-pulse device [0094] 45 Second capacitor [0095] 46 First capacitor [0096] 46 Transformer [0097] 47 Third capacitor [0098] 58 Force resulting from the magnetic field 42 and the current 60 in the conductor loop 6, acting on the moveable contact [0099] 59 U-shaped insulating jacket [0100] 60 Current or current flux I