WO2010018099A1

WO2010018099A1 - Busbar apparatus with current taps

Info

Publication number: WO2010018099A1
Application number: PCT/EP2009/060045
Authority: WO
Inventors: Frank Alefelder; Anton Frenzel; Rene Piotrowski; Olaf Wellner
Original assignee: Siemens Aktiengesellschaft
Priority date: 2008-08-13
Filing date: 2009-08-03
Publication date: 2010-02-18
Also published as: DE102008037968A1

Abstract

The invention relates to a busbar apparatus for busbar trunking systems in an electrical power supply system, in particular a three-phase low-voltage power distribution system. The busbar apparatus according to the invention allows heat to be exchanged between the busbars of the busbar apparatus for mutual cooling of the busbars. Furthermore, the current tap is not restricted to a small number of predetermined points on the busbar trunking system. Heat transmission between the busbars (11, 12) is assisted via a heat exchanging unit (W1, W2), which runs within a sandwich arrangement, for each busbar (11, 12). A contact section (K1, K2) which projects out of the sandwich arrangement, of each busbar provides a tapping area for the connection of electrical loads.

Description

description

Busbar device with power taps

The invention relates to a busbar device for

Busbar trunking in an electrical energy supply system according to the preamble of claim 1, in particular for a three-phase low-voltage energy distribution.

A common design of such busbar trunking is that several elongated shaped rail plates are arranged in parallel, wherein per phase of the electrical energy supply system, a rail plate are used as a phase conductor and one or more other rail plates as neutral. Optionally, in addition, a rail plate as

Protective conductor provided. The sheet metal plates may be actual sheets or similarly shaped profile parts such as e.g. to act extruded profiles.

An important aspect in the design of busbar trunking systems is their cost-effectiveness. It expresses u.a. in the amount of material needed to make a rail segment. For a given length of such a rail segment, the material requirement can be reduced by choosing the thinnest and narrower rail plates, i. the cross-sectional area of the rail plates is chosen as small as possible.

The opposite is the current carrying capacity of the rail plates. Rail panels must have a larger cross-sectional area, the greater the electrical currents that are to be routed via the busbar trunking. Otherwise, ie if the cross-section of the sheet metal is too small, the rail plates become too hot, which results in an increase in the specific resistance of the rail sheets, which in turn leads to further heating of the rail sheets. For a given sheet metal cross-section, the current-carrying capacity of a rail plate and thus the cost-effectiveness of the busbar device can be further increased by ensuring good heat dissipation from those rail sheets through which high currents flow. As a result, the heating of the rail plate and the concomitant increase in the specific resistance of the rail plate is reduced. An improvement in heat dissipation is achieved by the rail plates are spatially close to each other, so that there is an improved heat coupling between the sheets. If a phase in a three-phase network is heavily loaded by a load connected to the busbar, so that the corresponding current-carrying busbar is strongly heated, the thermal coupling between the busbars causes the resulting heat to be distributed to the busbars of less stressed phases and thus the current-carrying sheet is cooled. The close guidance of rail plates to increase the thermal coupling is also called sandwich arrangement.

In a sandwich arrangement, however, the connection of electrical loads to the busbar trunking is not directly possible because the small distance of the rail plates no space for the attachment of contacts, the so-called. Tap offers and even electrical flashovers between bare contact areas on the rail plates possible are. Therefore, specially trained rail segments are introduced along the course of the busbar trunking, which have rail plates with tapping options.

This Abgriffsmöglichkeiten can be created for example by the fact that the rail plates are laid in the provided for the connection of a consumer rail segment at a greater distance from each other. This makes it possible to connect contacts to bare contact areas of the rail panels. Because of the increased distance between the rail plates, however, the heat coupling greatly reduced between the rails, which can lead to excessive heating of a rail plate in this section, if this rail plate carries a strong current.

In order to be able to guide the rail plates closely in a sandwich arrangement even in the region of the tap, therefore, in another form of the tap, connections are led out transversely to the running direction of the rail device from a sandwich arrangement. This can be done by soldering a tapping element to each plate in the section in question. These tapping elements are fan-shaped apart, so that contact areas at these tapping elements are spaced far enough for the attachment of contacts.

As an alternative to soldering tap elements and tap elements are locally offset generated in the sheet edges by squeezing the sheet edges. The tapping elements thus produced protrude bead-like over the sheet bundle of the sandwich assembly and allow by their exposed position on the sheets and their mutual local offset along the path of the rails that uncovered contact areas and so conductors can be connected for the connection of electrical equipment ,

A disadvantage of the above-described solutions for power tapping for sandwich assemblies is the necessary special mechanical processing of a rail segment for the tap. When installing a power supply system with busbar trunking, the tap-off sections must be scheduled in advance. This means that the locations of the electrical consumers to be supplied must be known in the planning of the electrical distribution system. If an electrical load is added or added, the busbar trunking must be disconnected and a segment with tapping options for that load must be inserted. The invention is therefore an object of the invention to provide a busway with continuously in the direction continuously thermally coupled busbars and in addition to be connected to the current tap not a few predetermined points of the power busbar.

The object is achieved by a busbar device having the features of patent claim 1. Advantageous embodiments of the invention are described in the subclaims.

The busbar device according to the invention thus has at least one first and one second elongate busbar extending in a common longitudinal direction, the shape of the busbars and their arrangement in the busbar device being selected such that an imaginary plane passing through the center of gravity the first busbar and the center of gravity of the second busbar extends and which also extends in the longitudinal direction, the two busbars each divided into a contact portion and a heat exchange section and thereby results in a distance between the center of gravity of the contact portion of the first busbar and the center of gravity of the Contact portion of the second bus bar, which is greater than the distance between the center of gravity of the heat exchange portion of the first bus bar and the center of gravity of the heat exchange portion of the second bus bar.

The focal points of the defined by the imaginary plane contact or heat exchange sections can be determined in such a way that the contact and the heat exchange section of a busbar are considered to be solved from each other and the priorities of these independent sections are determined. The distance between the centers of gravity of the contact portions is preferably at least 1.005 times the distance between the centers of gravity of the heat exchange sections. In particular, it is preferably at least 1.01 times, at least 1.05 times or less. at least 1.1 times the distance of the centers of gravity of the heat exchange sections.

The geometrical boundary conditions according to the invention result in a busbar device with parallel busbars, which allows a comparatively high heat transfer over the heat exchange sections along its course in the longitudinal direction, since these areas are arranged spatially closer to each other. The heat exchange sections thus form a sandwich arrangement. At the same time are available with the contact portions areas that protrude from the sandwich arrangement and can be spaced far enough to attach contacts for connecting consumers to the busbar device can. Since the contact portions along the entire or almost entire course of the bus bars are formed, the above-mentioned technical problem is solved by the trained according to claim 1 busbar.

The (measurable) greater distance of the centers of gravity between the contact sections compared to the distance between the centers of the heat exchange sections results in the advantage that contact sections protrude over the entire extension of the busbar device according to the invention in the longitudinal direction or at least over a substantial part thereof from the sandwich arrangement , so that a connection of electrical consumers almost everywhere along the busbar device is possible.

As a busbar for a busbar device according to the invention is suitable in a special way a profile part, i. a preferably one-piece elongated workpiece whose profile is the same in a cross section perpendicular to the longitudinal direction over the course in the longitudinal direction, at least for the major part.

Another advantage of the inventively constructed busbar device is that from the sandwich arrangement protruding contact portions also serve as heat sink elements for the sandwich arrangement in such a way that heat which has been distributed by the thermal coupling of the busbars in the sandwich arrangement, led out via the contact portions of the sandwich assembly and discharged to the environment.

It is advantageous to arrange the busbar in such a way that the contact sections are located on the same side of the imaginary plane. On the same side of a plane, the two contact sections are if they are in a common area or hemisphere delimited by the imaginary plane. As a result, all contact sections are accessible from one direction. This enables fast connection and disconnection of electrical consumers.

A busbar device for a three-phase network advantageously has at least four busbars. This makes it possible to allow electrical consumers to tap the three phases (three-phase current) and the neutral conductor.

In a particularly advantageous embodiment of the busbar device according to the invention, the contact sections have tap areas for attaching contacts which have such a great distance from one another that a mutual electrical isolation already results from the ambient air between the tap areas of different busbars. As a result, the tap areas do not have to be insulated by electrically insulating materials. Contacts for connecting electrical loads can be quickly attached to or removed from the busbar device at the tap areas without the need for further measures relating to the isolation of the tap areas. The conductor rail device according to the invention can be realized in a particularly simple manner by busbars with an angled cross-sectional profile.

A further advantage results from the use of busbars which have profiles which are offset in cross-section. As a result, tap areas can be created on the busbar device, which are all aligned in parallel in the same spatial direction. This simplifies the attachment of contacts in a special way. By a cranked profile is to be understood that the profile of the busbar in a cross section perpendicular to the longitudinal direction has a staircase shape with a first and a second stage, wherein the two bending angles of the staircase-shaped profile are blunt than a right angle.

A busbar device with at least eight busbars has the advantage that two three-phase systems, each with three phases and one neutral conductor each, can be guided independently of one another in the busbar device. Here are the focal points of the contact portions of at least four of the busbars on one side of the imaginary plane, while the focal points of the contact portions of the remaining busbars are on the other side of the plane. On the same side of the imaginary

Plane are focal points of contact sections when they are in a common area bounded by the plane or half space.

It is also advantageous if the busbar device has a further busbar with a simple flat profile. Such a bus bar can be arranged within the sandwich arrangement and serve as a protective conductor. Also, use as an additional neutral conductor is possible, whereby a larger cross-sectional area is available for the neutral conductor. The invention will be explained in more detail below with reference to exemplary embodiments. The following drawings show:

1 shows a perspective view of a busbar device according to the invention,

2 shows a cross section of the arrangement of FIG. 1,

3 to 8 show cross sections of further embodiments of the busbar device according to the invention.

In the figures, with the exception of FIG 6, only the conductor elements of the bus bars are shown. Electrical insulations of the busbars, as they may still be to be accommodated between the busbars, are shown only in FIG. 6 (in an exemplary form).

In Figure 1, a bus bar device according to the invention is shown in a perspective view. On view are two busbars 11, 12, which extend predominantly along a common longitudinal direction, the longitudinal direction being indicated by the line L-L '. Since the extension predominates in the longitudinal direction, the dimensions of each busbar in other spatial directions are smaller. From the fact that the busbars extend in a common, ie the same longitudinal direction L-L ', they run parallel or at least largely parallel.

A plane E also extends in the longitudinal direction. Without this being shown in FIG. 1, the plane E should additionally run through the center of gravity of each illustrated busbar 11, 12. The plane E divides each of the bus bars 11, 12 into a respective contact section K1, K2 and a heat exchange section W1, W2. The heat exchange sections Wl, W2 are spatially very close to each other. On the other hand, the contact sections K1, K2 have regions in which the busbars 11, 12 are further spaced apart. FIG. 2 shows a cross section perpendicular to the longitudinal direction LL 'of the busbar device from FIG. Both busbars 11, 12 can be seen. The busbars 11, 12 have bent profiles. The cross section runs through the

Focus points Sl, S2 of the two busbars 11, 12. In FIG. 2, it can be seen that the center of gravity S1, S2 lie in the plane E from FIG. The plane E delimits an upper region B or a half-space from a lower region or half-space. In the upper region B are the contact portions Kl, K2 of the busbars 11, 12. The contact sections Kl, K2 can be assigned to focal points SKl, SK2.

On the other side of the horizontally extending in Figure 2 level E, i. underneath it are the heat exchange sections W1, W2 of the busbars 11, 12. They are therefore outside the area B. Focal points SW1, SW2 of the heat exchange sections W1, W2 can also be determined for heat exchange sections W1, W2. These have a distance AW to each other, which is smaller than the distance AK between the centers of gravity SKl, SK2 of the contact sections Kl, K2.

The cross sections in the following FIGS. 3 to 8 are all formed perpendicular to the longitudinal direction L-L 'described in connection with FIG.

In Figure 3 is a cross section through a bus bar device according to the invention is shown, are used in the busbars 11, 12 with flat profiles. The busbars 11, 12 are arranged offset to one another, so that a plane E through the focal points Sl, S2 of the busbars 11, 12 in the illustration in FIG 3 obliquely. Through the plane E is in each busbar 11, 12 a contact portion Kl, K2 delimited by a heat exchange section Wl, W2. The distance AK between the centers of gravity SKl, SK2 of the contact sections Kl, K2 is inventively greater than the distance AW between the centers of gravity SWl, SW2 of the heat exchange sections Wl, W2. Also in the embodiment shown in FIG Heat exchanger sections Wl, W2 according to the invention extend spatially close to each other in a sandwich arrangement. At the same time, the contact sections K1, K2 have free-standing regions which protrude from the sandwich arrangement and to which consumers can be connected.

In FIG 4 and FIG 5 each show a cross section through a busbar device according to the invention. In both figures, busbars 11, 12 are shown, which have simple angled profiles.

In FIG 4, an upper portion of the busbars 11, 12 is bent at an obtuse angle, wherein in cross-section, the upper legs of the busbars 11, 12 diverge, resulting in a Y-shape.

In FIG 5, the busbars 11, 12 on the other hand, L-profiles, so that there is a T-shape of the busbar device in cross section.

6 shows a cross section through a busbar device according to the invention with a total of four busbars 11-14. All busbars shown in FIG. 6 have cranked profiles comparable to those in FIG. The busbars 11-14 are in the area in which they are closely guided spatially, each with a solid insulating material II, 12, 13, 14 sheathed. Insulation of the busbars is possible in all embodiments of the busbar according to the invention also in the form that a plurality of busbars are surrounded by the same insulating body. This can be achieved, for example, by pouring several busbars into an insulating and hardening material.

As in FIG. 2, the contact sections in the upper region of the busbars are also located in FIG. 6 for each busbar 11-14, so that the contact sections are all accessible from one direction, from the top in FIG. The contact portions of the busbars 11-14 in FIG 6 have In addition, all a bare tap area Al, A2, A3, A4, which are therefore not covered by insulation II, 12, 13, 14. This is intended to indicate that the distance of the tap areas Al, A2, A3, A4 to each other is so great that electrical insulation of the tap areas against each other for voltages already present in a three-phase low-voltage power supply already exists through the medium surrounding the busbar device, ie, for example Ambient air results. Instead of air, however, it is also possible to use, for example, oil or sulfur hexafluoride.

The busbar device according to the invention shown in cross-section according to the invention comprises a total of eight busbars 11-18. Starting from the area in which the busbars are spatially narrow, ie the area of the sandwich arrangement, the contact sections of four busbars 11-14 have 7 upward and from the remaining four busbars 15-18 down. The busbars with the upwardly directed contact sections and those with the downwardly directed contact sections can be assigned to two different three-phase power supplies. Thus, in the busbar device in FIG. 7, there are two independent busbar devices of the type shown in FIG. 6, the two busbar devices being arranged point-symmetrically relative to one another. However, it is also conceivable to interconnect the busbars 11 - 18 in a different way with each other. So could e.g. alternately the contact region of a busbar upwards and an adjacent to be carried out from under the sandwich arrangement forth. This would be done by loading all three phases of one of the three-phase power supplies, e.g. the busbars 11 - 14, ensure by a three-phase load that heat dissipation through the bus bars 15 - 18 is ensured.

In Figure 8, a further embodiment of the bus bar device according to the invention is shown in cross section, in between the busbars 11 - 14 with contact portions an additional busbar 15 is arranged with a flat profile in the region of the narrow spatial guide (sandwich arrangement). Further, in FIG. 8, a housing 19 is shown with a cover 20, as it could be used as a housing for a busbar device. Without this being shown, the use of a housing is also possible for the remaining embodiments of the busbar device according to the invention.

The additional bus bar 15 can be used, for example, to increase the conductor cross-section of a phase conductor or the neutral conductor by attaching contacts, which are not shown in the figure, to one of the remaining bus bars. The use of the additional busbar as a protective conductor is also conceivable.

The described pouring of the bus bars into an insulating material can be achieved by using a housing 19, e.g. take place by the housing is filled up to a height with the insulating material, which still allows a connection of contacts to terminal areas comparable to those in FIG 6.

In all shown embodiments of the busbar device according to the invention, the busbars on a heat exchange section, via which a transfer of heat from one busbar to another busbar is favored by a spatially close management of the busbars. At the same time in the longitudinal direction of the busbar device electrical consumers without structural changes of

Busbar device are connected, since the busbars have a contact portion, which can provide sufficient space for the attachment of contacts.

Claims

claims

A busbar device for a busbar trunking system in a power supply system having at least a first and a second busbar (11, 12),

- Wherein the busbars (11, 12) extend predominantly in a common longitudinal direction (LL ') and an imaginary plane (E), by the center of gravity (Sl) of the first busbar (11) and the center of gravity (S2) of the second busbar (12) and extending in the longitudinal direction (LL '), the busbars (11, 12) in each case in a contact portion (Kl, K2) and a heat exchange section (Wl, W2) divided, characterized in that the distance (AK) between the center of gravity (SKl) of the contact section (K1) of the first busbar (11) and the center of gravity (SK2) of the contact section (K2) of the second busbar (12) is greater than the distance (AW) between the center of gravity (SWl) the heat exchange section (Wl) of the first bus bar (11) and the center of gravity (SW2) of the heat exchange section (W2) of the second bus bar (12).

2. Busbar device according to the preceding claim, in that there are the contact portions (Kl, K2) of the busbars (11, 12) on the same side of the imaginary plane (E).

3. Busbar device according to one of the preceding claims, d a d u r c h e c e n e c e in that the busbar device comprises a total of at least four busbars (11, 12, 13, 14).

4. Busbar device according to one of the preceding claims, characterized in that the contact portions of the bus bars each have a Abgriffsbereich (Al, A2, A3, A4), wherein the Abgriffsbereiche are electrically isolated by air against each other.

5. Busbar device according to one of the preceding claims, characterized in that the busbars in a cross section perpendicular to

Longitudinal in each case have a simple angled profile.

6. Busbar device according to one of claims 1 to 4, d a d e r c h e c e n e c e in that the busbars in a cross section perpendicular to the longitudinal direction each have a cranked profile.

7. Busbar device according to one of the preceding arrival claims, characterized in that the busbar device comprises a total of at least eight busbars, wherein the contact portions of at least four of the busbars (11, 12, 13, 14) on a common side of the plane and the contact portions the remaining busbars (11, 12, 13, 14) are located on the other side of the plane.

8. Busbar device according to one of the preceding claims, d a d u r c h e c e n e c e in that the busbar device additionally comprises a busbar (15) whose profile is a flat profile in a cross section perpendicular to the longitudinal direction.