WO2014068053A1

WO2014068053A1 - Dc switchgear

Info

Publication number: WO2014068053A1
Application number: PCT/EP2013/072804
Authority: WO
Inventors: Johann Koppensteiner
Original assignee: Eaton Industries (Austria) Gmbh
Priority date: 2012-10-31
Filing date: 2013-10-31
Publication date: 2014-05-08
Also published as: DE102012110410A1; CN104813429B; CN104813429A; BR112015009673A2; EP2915175B1; EP2915175A1; RU2015120617A; RU2656231C2

Abstract

The invention relates to a DC switchgear (1) with at least one electrical input (2) and at least one electrical output (3), and with at least one first switching contact (4), a second switching contact (5) and a mobile jumper (20), a current path being electrically conductive from the input (2) to the output (3) when the first switching contact (4) and the second switching contact (5) are conductively connected by means of the jumper (20), the DC switchgear (1) further comprising an arc extinguishing assembly (6). According to the invention, the arc extinguishing assembly (6) comprises a first arc extinguishing chamber (7) and a second arc extinguishing chamber (8), each comprising a plurality of extinguishing plates (9). The DC switchgear (1) further comprises a magnet array (10) which is configured such that a Lorentz force (12) acts upon arcs (11), which are caused by a switching process, in the first arc extinguishing chamber (7) and in the second arc extinguishing chamber (8) in the direction of the extinguishing plates (9).

Description

DC SWITCHGEAR

The invention relates to a DC switching device according to the preamble of

Claim 1.

There are switching devices for switching DC currents known per se. However, the use of direct current for a long time was usually limited to the low power range in which there were hardly any problems in switching the direct currents.

Since the spread of photovoltaic applications and powerful battery back-up systems for computerized server systems, it is also necessary to switch DC currents of higher voltage and power. The known AC switchgear have proved unsuitable in many respects. For example, when switching DC currents with an AC switch, even at voltages and currents far below the maximum AC power limits of the AC switch concerned, it can

Total loss come. As a result, in addition to the failure of an electrical system, this can also lead to a fire.

The object of the invention is therefore to provide a DC switching device of the type mentioned, with which the mentioned disadvantages can be avoided, and with which DC currents high power can be switched safely.

This is achieved by the features of claim 1 according to the invention.

Thereby, a DC switching device can be created, which is a high

Switching capacity at direct currents, and which is therefore suitable

To switch high current DC currents. Such a DC switching device has a high level of security, in particular against thermal destruction.

The subclaims relate to further advantageous embodiments of the invention. It is hereby expressly referred to the wording of the claims, whereby the claims at this point are incorporated by reference into the description and are considered to be reproduced verbatim.

The invention will be described in more detail with reference to the accompanying drawings, in which only preferred embodiments are shown by way of example. Showing:

Fig. 1 shows a particularly preferred embodiment of a subject

DC switching device in a partially sectioned view in elevation;

FIG. 2 shows the arc extinguishing arrangement of the DC switching device according to FIG. 1 in axonometric representation; FIG. and

Fig. 3, the arc extinguishing arrangement of FIG. 2 in a sectional view in elevation.

Figs. 1 to 3 show a particularly preferred embodiment of a

DC switching device 1, or an arc extinguishing arrangement 6 of such

DC switching device 1, wherein the DC switching device 1 has at least one electrical input 2 and at least one electrical output 3, and with at least a first switching contact 4, a second switching contact 5 and a movable

Switching bridge 20, wherein a current path from the input 2 to the output 3 is electrically connected, when the first switching contact 4 and the second switching contact 5 are conductively connected by means of the switching bridge 20, wherein the DC switching device 1 further comprises an arc extinguishing arrangement 6, wherein the arc extinguishing arrangement 6 a first arc quenching chamber 7 and a second arc quenching chamber 8, each comprising a plurality of quenching plates 9, and wherein the DC switching device 1 has a magnet assembly 10 which is formed such that on - by a

Switching caused - arcs 11, in the first arc quenching chamber 7 and in the second arc quenching chamber 8, each a Lorentz force 12 in the direction of

Fire plates 9 acts.

Thereby, a DC switching device 1 can be created, which is a high

Switching capacity at direct currents, and which is therefore suitable

To switch high current DC currents. Such a DC switching device 1 has a high level of security, in particular against thermal destruction. The subject invention relates to switching devices, which are provided for the switching of direct currents and specially designed. In particular, the invention relates to DC switching devices 1, which are intended and designed for the intended switching high voltages in the range of several hundred volts, about 600V operating voltage, as well as currents in the two-digit ampere range.

Hereinafter, the invention with reference to a preferred embodiment of a

DC switching device 1 described in more detail with a single switching path. However, it is also possible to provide designs with several parallel switching paths.

An objective DC switching device 1 has an electrical input 2 and an electrical output 3, which are preferably designed as screw terminals, as shown in Fig. 1. Furthermore, the DC switching device 1 has a

Insulating housing on.

The DC switching device 1 has a single switching path, but with a double interruption of this single switching path is provided. It is preferably provided that the first and the second switching contact 4, 5 are fixed to the housing, and can be electrically connected by a movable switching bridge 20, whereby an electrically conductive current path from the input 2 to the output 3 is formed. It is provided that the position of the switching bridge 20 is manually controlled by the shift lever 19. It is preferably provided that the shift lever 19 acts on the switching bridge 20 via a snap-action switching mechanism in order to achieve a sudden opening and closing of the switching path. It may also be provided to carry out the subject DC switching device 1 as so-called. Self-switch, which one or more triggers, such as a

Overcurrent release and / or has a short-circuit release. Furthermore, it is preferably provided that the DC switching device 1 has a switching mechanism, in particular when the same is carried out as a self-switch.

With closed switching contacts, the current flow through the illustrated

DC switching device 1 from the electrical input 2 to the first switching contact 4, from this via the switching bridge 20 to the second switching contact 5 and from this further to

Although the switching bridge 20 has two, designed as electrical contacts areas to the first switching contact 4 and the second

To contact switching contact 5, this is in the diction of the subject application only referred to as a switching bridge 20. It can also be provided that also the first switching contact 4 and the second switching contact 5 are designed as movable electrical contacts.

The DC switching device 1 further comprises an arc extinguishing arrangement 6 in order to extinguish arcs 11, which arise in the course of a switching operation, to extinguish. This is to prevent that due to so-called "stationary" arcs 11 continues to flow through the DC switching device 1 and also due to the thermal effect of the arcs 11 damage to the DC switching device 1 takes place.

Such arcs 11 occur in particular during a switch-off.

"Switching off" refers to the separation of the switching bridge 20 of the first and second electrical switching contact 4, 5 to prevent current flow through the DC switching device 1. The physical relationships in the ignition of a

Arcs are described in the induction law.

Fig. 2 shows a preferred embodiment of the arc extinguishing arrangement 6. In the

Representation of FIG. 2, the first switching contact 4 and the second switching contact 5 are shown, but these are shown without any further contact, only their arrangement relative to the respective arc extinguishing chambers 7, 8 to

illustrate. The same applies to the switching bridge 20 likewise shown in FIG. 2.

The arc extinguishing arrangement 6 has a first arc quenching chamber 7 and a second arc quenching chamber 8. It is preferably provided that the first

Arc quenching chamber 7 is assigned to the first switching contact 4, and that the second arc quenching chamber 8 is associated with the second switching contact 5. The term "assigned" refers in this context to an arrangement of the relevant arc quenching chamber 7, 8 with respect to the specified switching contact 4, 5 in such a way that an emerging at the switching contact 4, 5 arc 11 its way into or to the relevant arc quenching chamber 7, 8 shows the two switching contacts 4, 5 in the region of the respective arc quenching chamber 7, 8.

Preferably, as in the illustrated embodiment, it is provided that the first

Arc quenching chamber 7 and the second arc quenching chamber 8 in the

DC switching device 1 are arranged parallel to each other, as shown in FIGS. 2 and 3. It is preferably provided that in each case one arc guide rail 18 is connected in each case to the first switching contact 4 and to the second switching contact 5, which are arranged opposite the quenching plates 9 in the arc extinguishing arrangement 6, therefore in the respective arc quenching chamber 7, 8. In FIGS. 1 to 3, only the arc running rail 18 connected to the first switching contact 4 is shown.

In the first arc quenching chamber 7 and the second arc quenching chamber 8, a plurality of quenching plates 9 are arranged in each case. The quenching plates 9 are preferably arranged substantially normal to the arc guide rail 18. In each case at least one quenching plate 9 of the first arc quenching chamber 7 is in this case with a

Splitter plate 9 of the second arc extinguishing chamber 8 electrically connected.

If the switching bridge 20 is moved away from the first switching contact 4 and the second switching contact 5 during a current flow via the DC switching device 1, an arc 11 is formed from the first switching contact 4 to the switching bridge 20, as well as another one

Arc 11 from the switching bridge 20 to the second switching contact 5. At a certain length of the to be bridged by the arcs 11 air gap these jump to the

Extinguishing plates 9 of the arc extinguishing chambers 7, 8 via. It has been found that the present at this time arcs 11 have an astonishing stability, and it may be that these arcs 11 at the respective quenching plates 9, where they contact, remain, until it is for the thermal destruction of the

DC switching device 1 comes. This problem is not known in the AC technique in the way it comes to quickly extinguishing occurring AC arcs due to the constant zero crossings of the applied voltage.

It is therefore provided that the DC switching device 1 has a magnet assembly 10 which is designed such that on the - caused by a switching operation - arcs 11, in the first arc quenching chamber 7 and in the second

Arc quenching chamber 8, each a Lorentz force 12 in the direction of the quenching plates 9 acts. Therefore, that acts on the respective occurring arcs 11 a Lorentz force 12 which accelerates the arc 11 in the first arc quenching chamber 7 and the arc 11 in the second arc quenching chamber 8 toward the quenching plates 9 and the arcs 11 formally to the quenching plates 9 and in the spaces between the quenching plates 9 presses. Since an electric arc 11 involves moving electric charges, corresponding forces also act on them in a magnetic field. In other words, it is provided that the magnet arrangement 10 generates a B-field which is normal to the longitudinal extension of the arcs 11 in the region of the arcs 11. This is shown approximately in FIG. 3, which shows a particularly preferred embodiment of the subject invention. 3, the two arcs 11 are shown as vectors, which are arranged projecting on the cutting plane, as well as the respectively acting Lorentz forces 12 and F. The areas in which arcing 11 occur and their direction, are by the construction of the DC switching device 1 or can be influenced by the construction of the DC switching device 1.

Any type of arrangement of magnets in the magnet assembly 10 suitable for achieving the stated function may be provided. It is preferably provided that the magnet arrangement 10 has at least one first magnet 13 and one second magnet 14, in particular that the magnet arrangement 10 has exactly one first and one second magnet 13, 14. This is in the arrangement with two separate

Arc quenching chambers 7, 8 a very good effect achievable with little design effort.

It has proven to be particularly easy to implement embodiment of the subject invention, that the first magnet 13 and the second magnet 14 are arranged with mutually facing poles of the same polarity in the DC switching device 1.

Therefore, for example, the first magnet 13 and the second magnet 14 are respectively arranged such that their north poles face each other, therefore, the two magnets 13, 14 repel each other.

It has proven to be advantageous in this case to carry out the first magnet 13 and the second magnet 14 in each case as flat or sheet-like magnets, with a very small thickness, whose poles are respectively formed on the cover surfaces. Therefore, one of the two surfaces is a south pole and the other surface is a north pole. Preferably, the magnets used are each permanent magnets.

To be particularly advantageous, the arrangement of the first magnet 13 has laterally on the first arc quenching chamber 7 and the second magnet 14 laterally to the second arc quenching chamber 8 proved, creating a very uniform B field distribution in the two arc extinguishing chambers 7, 8 can be achieved.

It has proved to be particularly advantageous, in particular with regard to production, that the first magnet 13 and the second magnet 14 are arranged between the first arc quenching chamber 7 and the second arc quenching chamber 8. The two magnets 13, 14 are arranged in a web 15 between the two arc extinguishing chambers 7, 8, as shown in Fig. 3. In Fig. 2, the web 15 thus formed is clearly visible. By this web 15 also results in a distance between the two

Arc quenching chambers 7, 8, which the thermal capacity of the entire

Arc extinguishing arrangement 6 increases. To achieve a uniform magnetic field B in the two arc extinguishing chambers 7, 8 is provided according to a preferred embodiment that outside the first arc quenching chamber 7 and the second arc quenching chamber 8 each partially a U-shaped yoke 16, 17 is arranged. It is provided in particular, and as shown in Fig. 3, that mutually facing legs of the two yokes 16, 17 are arranged adjacent to each other in the region of the web 15, and in each case directly adjacent to these legs of the first and the second magnet are arranged. The two yokes 16, 17 are formed of ferromagnetic material.

Claims

claims

1. DC switching device (1) with at least one electrical input (2) and

at least one electrical outlet (3) and at least one first

Switching contact (4), a second switching contact (5) and a movable switching bridge (20), wherein a current path from the input (2) to the output (3) is electrically conductive when the first switching contact (4) and the second switching contact (5) by means of the switching bridge (20) are conductively connected, wherein the DC switching device (1) further a

Arc extinguishing arrangement (6), characterized in that the

Arc quenching assembly (6) comprises a first arc quenching chamber (7) and a second arc quenching chamber (8), each comprising a plurality of quenching plates (9), and that the DC switching device (1) comprises a magnet assembly (10) which is designed such that on - Arcs caused by a switching process

(11), in the first arc quenching chamber (7) and in the second

Arc quenching chamber (8), in each case a Lorentz force (12) in the direction of the quenching plates (9) acts.

2. DC switching device (1) according to claim 1, characterized in that the first arc quenching chamber (7) and the second arc quenching chamber (8) in the

DC switching device (1) are arranged parallel to each other.

3. DC switching device (1) according to claim 1 or 2, characterized in that the magnet arrangement (10) has at least one first magnet (13) and a second magnet (14).

4. DC switching device (1) according to claim 3, characterized in that the first magnet (13) and the second magnet (14) are arranged with mutually facing poles of the same polarity in the DC switching device (1).

5. DC switching device (1) according to claim 3 or 4, characterized in that the first magnet (13) and the second magnet (14) between the first

Arc quenching chamber (7) and the second arc quenching chamber (8) are arranged.

6. DC switching device (1) according to one of claims 1 to 5, characterized in that outside the first arc quenching chamber (7) and the second

Arc quenching chamber (8) each area a U-shaped yoke (16, 17) is arranged.

7. DC switching device (1) according to one of claims 1 to 6, characterized in that in each case an arc guide rail (18) with the first switching contact (4) and with the second switching contact (5) is in each case conductively connected, which in relation to the

Extinguishing plates (9) in the arc extinguishing arrangement (6) are arranged.