EP1406369B1 - Device for inductive coupling of electric signals to a voltage supply line and method for making a wound web - Google Patents

Abstract

Device for inductively coupling electrical signals (power line communications signals) with a voltage supply line (12) having an insulating sleeve (15) comprises a loop (13) made from a nanocrystalline or amorphous ferromagnetic material and consisting of two annular parts (16a, 16b). An Independent claim is also included for a process for processing a band coil made from a nanocrystalline or amorphous ferromagnetic material comprising feeding the band coil into a pot-like container, impregnating the coil with a casting composition and separating the coil into at least two parts.

Description

The invention initially relates to a device for the inductive coupling of electrical signals (PLC signals) to a particular current-carrying, possibly provided with a Isolierumhüllung voltage supply line according to the preamble of claim 1.

To realize a data or signal transmission over an existing power supply network, a great deal of effort has already been made. A special aspect relates to the coupling of the PLC (Powerline Communication) signals on high-voltage lines, medium-voltage lines and low-voltage lines. The term signal coupling is intended to allow bi-directional data transmission in the context of the invention, ie both the Aufspielen of signals on the power supply line as well as the decoupling or decoupling existing on the power supply line to be transmitted signals.

The aim of the invention is to further develop the Ankoppelstelle, the type of signal coupling is inductive. Inductive signal coupling means that the coupling is effected indirectly by magnetic excitation of a magnetic element and does not take place in a capacitive manner or by direct electrical contacting of the voltage supply line.

The coupling of signals to a power supply line prepares i.a. problems when the power supply lines have large cross sections, as is the case with high, medium and low voltage lines. If signal coupling is to take place, for example, in the area of a transformer station, the available installation space for such a device is also limited.

It is finally known to carry out a signal coupling directly by an electrical contacting of the power supply line. In this case, however, the power supply line, which is provided with an insulating sheath and in some cases flows through very high currents of up to a few 100 amperes, must be processed by highly specialized experts who carry out stripping.

In addition, it has already been considered to encompass power supply lines with so-called folding ferrites. Although an inductive signal coupling is already possible in this way. The problem, however, is a saturation of this arrangement which, with the high currents of perhaps 300 or 400 amperes flowing through the power supply line, leads to an impractical, very limited use of the device due to a very narrow usable frequency band. In addition, additional capacitive components are regularly provided in such folding ferrites, so that in these contemplated coupling points only in a very narrow band resonance range, which is determined by the inductance of the folding ferrite together with the capacitive element, a signal transmission is possible. Finally, the folding ferrite can not be designed too voluminous.

The object of the invention is to develop a device according to the preamble of claim 1 such that it enables an improved inductive coupling of electrical signals to a power supply line.

The invention solves this problem with the features of claim 1, in particular with those of the characterizing part, and is accordingly characterized by a substantially annular clamp of nanocrystalline or amorphous ferromagnetic material which can be assembled from at least two parts.

The principle of the invention is therefore first to use a clamp made of a special material. In contrast to ferrites, which do not fulfill the desired magnetic properties for an optimized coupling of signals to a voltage supply line, nanocrystalline or amorphous ferromagnetic materials are particularly suitable for this purpose.

Such materials, which are produced in a very complex manner, in particular by means of rapid solidification technology by casting a melt with extremely rapid cooling, directly into a thin strip, are available, for example, from the company Vacuumschmelze under the trade names Vitrovac and Vitroperm. Further information is available at www.vacuumschmelze.de, for example.

These are soft magnetic materials, ie those materials in which the hysteresis loop is designed to be particularly narrow.

Nanocrystalline or amorphous ferromagnetic materials offer, for example, a particularly high initial permeability, which may be, for example, in the range of 20,000 or 40,000, but also higher. A high initial permeability, ie a maximum μ _r at initial, initial magnetic excitation by a current (ie the slope of a new curve in a BH diagram), is of particular importance.

The term amorphous expresses a particular ordering property of the ferromagnetic material, and describes the fact that in this material no long-range order or crystal structure is present. This amorphous state corresponds to the material state immediately after shock freezing. By a subsequent heat treatment or annealing process, a change in state from the amorphous to a nanocrystalline state takes place. Nanocrystalline in this context means that the grain sizes of the magnetic districts are in the nanometer range (average diameter 10 to 20 nm). In addition, nanocrystalline materials are usually characterized by a two-phase structure in which a fine-crystalline grain having the above-mentioned grain diameter is embedded in an amorphous residual phase.

In addition to very high saturation inductions, the initial permeability plays a special role as the physical size and measurable feature of these materials. For example, by using such materials with such high initial permeabilities as stated above, with an assumed minimum coupling factor of -3 dB and a lower transmission frequency of 2 MHz, an inductance L of the device of 4 μH can still be achieved.

Further details of the type of material used for the device are described below.

A second aspect of the invention provides that the clamp made of nanocrystalline or amorphous, ferromagnetic material composed of at least two parts and is annular. In this way, a device is possible, which surrounds the power supply line on its outer circumferential surface, and due to the Zertrenn- or decomposability or assemblability readily mountable, namely, can be placed on the power supply line. The possibly existing Isolierumhüllung the power supply line must not be injured for this purpose become. The assembly as well as the dismantling of the device according to the invention can thus be carried out by specialized personnel, which does not have to have the necessary knowledge for a stripping.

Optionally, to ensure the cohesion of the at least two parts in use, fasteners such as screw, may be provided. It can alternatively be used but also tape, since the clamp is not exposed to any special mechanical forces.

As a power supply line in the context of this invention, for example, a medium voltage line is understood, which has an inner, electrically conductive core and an outer, electrically insulated shield, for example, a mesh of metallic threads. In the case of these so-called coaxial cables, with the device according to the invention, the signals can be coupled directly to the shielding, and a digital transmission can pass through the shielding. However, it can also be provided to first carry out a signal coupling onto the shield and to transmit the signal for forwarding to the inner core, that is to say the core of the coaxial cable, by means of a special circuit.

From the WO 02/46777 For example, a measuring apparatus for measuring leakage currents is known, which contains an inner core of amorphous ferromagnetic material. From this document, it is not known to assemble a clamp of a nano-crystalline or amorphous, ferromagnetic material of two parts.

From the US-A-5,341,280 is a device for transmitting electrical power from a power source to an electrical load known. The known device has a magnetic core, which consists in a forceps-like arrangement of two hinged together with hinged parts.

From the US 3,924,223 is a device for inductive coupling of PLC electrical signals to a particular current-carrying power supply line, with a substantially annular, composed of two parts clamp made of a magnetic material. This document shows so-called "folding ferrite", which have already been explained at the outset. A clamp made of nanocrystalline or amorphous, ferromagnetic material is not apparent from this document.

From the EP 0 302 746 A2 is a process for producing a tape roll of the material VATROVAC-6025F out (see column 7, lines 37 to 63). However, this document does not show a method that divides such a tape roll into at least two parts.

In accordance with a further aspect of the invention, due to its geometric structure, the clamp furthermore offers the possibility of signal coupling to a voltage supply line even at locations where the voltage supply line is strongly curved. Due to a clamp-like design with only a small thickness of the radius of curvature plays a minor role.

According to one embodiment of the invention, the clamp is composed of two substantially semicircular parts. This allows on the one hand an arrangement with a small number of components, so that the handling is easier. On the other hand, in this embodiment, only two separating cuts, for example, along a common diameter plane of a substantially annular belt coil required, so that the tape roll is minimally damaged in its structure.

According to a particularly advantageous embodiment of the invention, the clamp is formed from a continuous annular band wound, which is divided into at least two parts. This embodiment of the invention makes it possible, inter alia, to use conventional, commercially available annular belt coils of nanocrystalline or amorphous, ferromagnetic material.

According to a further advantageous embodiment of the invention, the tape roll is cut at least along a plane. A cut along a plane, in particular along a common diameter plane, offers the possibility of minimizing the risk of damage to the inner structure of the band roll.

According to a further advantageous embodiment of the invention, the tape roll on a particular prior to cutting attached impregnation in the manner of a potting compound. The provision of a potting compound offers the possibility to reinforce the tape wrap in its structure before cutting, in particular to stiffen. A cutting of such a reinforced tape winding creates ever a condition of the tape roll by this can be divided into two parts. The potting compound can, depending on the state of delivery of the tape roll, penetrate into free spaces, in particular in pores of the tape roll and in spaces between the layers. However, it is also conceivable that the potting compound is disposed substantially on the outer surfaces, so for example on the outer circumferential surface and on the annular end faces of the tape roll and surrounds the tape roll in this way corset-like.

According to a further advantageous embodiment of the invention, the potting compound is a resin, in particular a thermosetting epoxy resin or a temperature-resistant polyester resin. This embodiment of the invention enables the use of inexpensive and commercially available potting compounds with particularly good processability and handling.

According to a further advantageous embodiment of the invention, the tape roll has been subjected to vacuum before impregnation and the potting compound in open spaces, eg. B. penetrated into pores of the tape roll. The provision of vacuum before impregnation offers the possibility of a particularly good and safe corset formation by the potting compound.

According to a further advantageous embodiment of the invention, the clamp in the assembled state in the mating region of each two adjacent parts on a thin gap. The joining region, that is to say the region in which two neighboring parts abut each other almost, is provided according to this advantageous embodiment with a thin, in particular defined gap. The gap may for example have a width of the order of 10 microns and be filled with air or paper, possibly also with an adhesive strip. It is important that the gap is filled with a non-magnetic and non-conductive material. In particular, in this context of importance that the cut surfaces of the tape roll in the mounted state of the clamp are not directly adjacent to each other. It is also advantageous in this context that the cut surfaces are particularly smooth or flat and show no fringe formation, which would be disadvantageous for magnetic reasons.

The invention further relates to a method for processing a substantially annular band wound of nanocrystalline or amorphous ferromagnetic material according to the preamble of claim 16.

Such a processing method is not known. The commercially available tapes listed above are usually very brittle, and even more brittle after heat treatment, ie after their transfer from the amorphous to the nanocrystalline state. The tape roll produced in this way usually represents the final shape, ie the finished processed state of the tape roll. The known tape wraps are usually transported in toroidal containers and find use as storage chokes. Optionally, a sintered material can be additionally attached here.

The object of this invention is to provide a machining method according to the preamble of claim 16, which allows the use of the processed tape roll in a device for inductive coupling of electrical signals to a particular current-carrying, possibly provided with Isolierumhüllung power supply line.

1. a) Einbringen des Bandwickels in ein topfartiges, evakuierbares Behältnis,
2. b) Imprägnieren des Bandwickels mit einer Vergussmasse,
3. c) Zertrennen des Bandwickels in wenigstens zwei Teile,

wobei der Bandwickel wenigstens im Bereich der Trennstellen imprägniert wird.The invention solves this problem with the features of claim 16, in particular with the characteristics of the characterizing part, and is accordingly characterized by the steps

1. a) introducing the tape roll into a cup-like, evacuable container,
2. b) impregnating the tape roll with a potting compound,
3. c) severing the tape roll into at least two parts,

wherein the tape roll is impregnated at least in the region of the separation points.

The principle of the invention thus consists essentially of a conventional, finished, substantially annular band wound, the a plurality of winding layers nanocrystalline or amorphous, ferromagnetic material is first to introduce into a container. Subsequently, a potting compound can be introduced into the container with which the tape roll is impregnated or impregnated. The potting compound is in particular, if according to an advantageous embodiment of the invention, the container is evacuated and is applied after the introduction of the tape roll in the container and before impregnating the tape roll of the tape roll with a vacuum, due to the existing vacuum in the free spaces, so if necessary The column or pores of the ribbon wrap are sucked in. Even if no vacuum is applied, in principle it is possible to provide by attaching the potting compound for a stiffening, which occupies at least the surfaces, so the outer sides of the tape roll with potting compound. However, the application of a vacuum is much more advantageous.

After impregnation, the tape roll can be cut into at least two parts, for example cut. It is sufficient in principle if the tape roll is impregnated at least in the region of those points at which a separation takes place subsequently.

The processing method according to the invention provides a possibility to initially provide the tape roll with a corset in the form of the potting compound, which ensures a stiffening of the tape roll, so that it can be subsequently severed. The application of a vacuum to the tape roll before the process step of impregnation ensures a particularly close concern of the corset-like potting compound or for a certain penetration, if necessary. The nanocrystalline or amorphous, ferromagnetic material which was originally very brittle and can not readily be processed, which is unsuitable for subsequent processing, is thus even brought into a form in which the ribbon wound can be severed.

Fig. 1

schematisch in teilgeschnittener Ansicht einen Querschnitt durch eine erfindungsgemäße Vorrichtung zur induktiven Ankopplung von elektrischen Signalen mit einer Schelle sowie eine mit einer Isolierumhüllung versehene Spannungsversorgungsleitung,

Fig. 2

die Anordnung gemäß Fig. 1 etwa gemäß Ansichtspfeil 11 in einer perspektivischen, schematischen Ansicht,

Fig. 3

in vergrößerter Darstellung, einen Fügungsbereich zwischen zwei eine Schelle bildenden Teilen etwa gemäß Teilkreis III in Fig. 1, und

Fig. 4

schematisch, in teilgeschnittener Ansicht etwa gemäß Schnittlinie IV-IV in Fig. 1, unter Weglassung der Spannungsversorgungsleitung, und nicht maßstabsgetreu, einen bearbeiteten Bandwickel, wobei gestrichelt zusätzlich ein evakuierbares Behältnis dargestellt ist.

Further advantages of the invention will become apparent from the non-cited subclaims and with reference to the following description of an embodiment shown in FIGS. In the drawings show:

Fig. 1

1 is a schematic partial cross-sectional view of a device according to the invention for the inductive coupling of electrical signals to a clamp and a voltage supply line provided with an insulating sheath, FIG.

Fig. 2

the arrangement according to Fig. 1 approximately in accordance with arrow 11 in a perspective, schematic view,

Fig. 3

in an enlarged view, a mating area between two parts forming a clamp approximately according to pitch III in Fig. 1 , and

Fig. 4

schematically, in a partially sectioned view approximately according to section line IV-IV in Fig. 1 , omitting the power supply line, and not to scale, a processed tape roll, with an additional evacuated container is shown in dashed lines.

The apparatus designated in its entirety in the figures with 10 for the inductive coupling of electrical signals is first based on the Fig. 1 explained as follows:

A merely schematically indicated signal generator / signal receiver module 11 transmits or receives electrical signals, in particular high-frequency signals. Usually they are signals of a frequency range approximately between 2 and 20 MHz, in which data is transmitted. The electrical signals should be loaded onto a power supply line 12 or tapped from this line 12, so that a data transmission via the power supply network can be performed. The power supply line 12 is, for example, a high voltage power line, a medium voltage line or a low voltage line on which typically AC voltage in the kilovolt range with a low frequency, for example 50 to 60 Hz is applied. Since the signals are high frequency signals, signal transmission and provision of electrical power through the power grid, which is primarily the target of the power grid, does not interfere.

According to Fig. 1 the power supply line 12 is provided with an insulating sheath 15. This does not necessarily have to be the case, but is common with the voltage supply lines concerned here.

According to Fig. 1 the conduit 12 is encompassed on its outer circumferential surface by a clamp 13, which consists of two substantially semicircular elements 16a and 16b.

From the schematic, perspective view according to Fig. 2 it is clear that the clamp 13 is a substantially annular body. Between the inner peripheral surface 36 of the clamp 13 and the outer circumferential surface 37 of the power supply line 12 (FIG. Fig. 1 ) is an annular space 38, whose arrangement and size is not relevant. However, it is crucial that a signal line 14, which is connected to the signal generator / signal receiver module 11, surrounds the clamp 13 in the manner of half a winding and for this purpose passes through the annular clearance 38.

The basic physical principle of such an inductive coupling of signals to a voltage supply line 12 is as follows:

High-frequency signals, which are on the signal line 14, cause a magnetic excitation of the clamp 13, since this consists of ferromagnetic material, wherein the material itself will be discussed later in detail. The magnetic excitation gives the clamp 13th then to the power supply line 12 on, again in the form of electrical pulses (voltages). The clamp thus acts in the manner of a transformer, wherein the signal line 14 and the power supply line 12 represent a primary winding and corresponding to a secondary winding of a transformer with the winding number 1. Strictly speaking, the signal line 14 surrounds the clamp 13, although only with half a winding and the power line 12 due to their large, approximately infinite length, the clamp 13 also only in the manner of half a winding. However, consideration such that power line 12 and signal line 14 are actually one full turn is acceptable in this geometry.

What is desired in this arrangement, on the one hand, is a very broadband transmission range, that is, only a very low attenuation of signals in a large frequency range. In other words, a uniform coupling factor over a wide frequency range is advantageous.

On the other hand, it is of particular importance that the clamp 13 remaining permanently on the voltage supply line 12 does not hinder the basic function of the voltage supply network. It should be noted in particular that currents of up to a few 100 A, typically about 300 or 400 A, flow through the voltage supply line 12, so that with regard to the magnetic properties of the clamp 13 special requirements must be met, and in particular saturation is prevented.

The solution according to the invention provides that the clamp 13 consists of nanocrystalline or amorphous, ferromagnetic material. Such a material is an alloy called soft magnetic material. Soft magnetic in this context means that the hysteresis curve, ie the curve in a BH diagram, represents a particularly narrow hysteresis loop. The narrower the hysteresis loop, that is, the smaller the area between the two branches, which or Abbewegung (eg, an alternating current through the power supply line 12 therethrough), the lower are electrical losses, which means a conversion into heat energy.

The alloy composition of these materials is usually formed from the basic elements iron, cobalt and nickel and additional elements such as silicon, boron, manganese, copper, niobium, molybdenum or chromium. The exact nature of the composition, both in terms of the nature of the ingredients and their proportions will not be discussed here. However, nanocrystalline or amorphous ferromagnetic materials are commercially available, for example, from the company Vakuumschmelze. The preparation of such materials is extremely complicated, and instead of conventional subsequent process melting, as is the case with crystalline materials, by rapid solidification technology, by casting a melt with extremely rapid cooling, the material is made into a thin strip. The tapes are usually wound at very low temperatures, for example nitrogen-cooled coils on a tape winding (ring band core).

Such a tape roll is initially schematically in the Fig. 4 represented and designated by the reference numeral 23. A band winding 23 consists of a plurality of winding layers 19, which are wound from a radially innermost winding layer 20 having a radial inner end, not shown, to a radially outer winding layer 21 with an outer radial end, also not shown. The commercially available tape wraps usually have tape thicknesses in the micron range, that is, a winding layer 19 of such a tape roll 23 has approximately a tape thickness of for example 23 microns (about 20 to 25 microns). A tape roll 23, as it is commercially available, is extremely brittle and easily unworkable. The material of the tape roll, that is nanocrystalline or amorphous, ferromagnetic material is used according to the invention for producing a clamp 13. First, therefore, the processing method for processing a Bandwickels 23 are explained from nanocrystalline or amorphous, ferromagnetic material.

According to Fig. 4 the tape roll 23 is a circular trained body, the first in one in the right half of the Fig. 4 only schematically indicated cup body 22 is arranged. The cup body 22 has a substantially U-shaped cross section with a bottom wall 39 and two side walls formed by the U-legs 40a, 40b, so that an annular groove-like receptacle for the tape roll 23 is provided. In the area of the side walls are in addition, like that the left half of the Fig. 4 makes clear, silicone pad members 24a and 24b provided that store the vulnerable tape roll 23 soft. For the sake of clarity, with respect to a central longitudinal axis M right half of Fig. 4 indicated only schematically and the left half of Fig. 4 shown in more detail.

At an engaging in the material of the tape roll 23 processing the tape roll 23 is unthinkable due to the brittle, highly fragile state of the tape roll.

According to the tape winding 23 is introduced for processing together with the cup 22 in an evacuable container 25, which in Fig. 4 is shown in dashed lines. The evacuable container 25 has a bottom element 27, a centrally located centrally disposed mandrel 26 and side walls 28, so that a ringnutartiger receiving space for the cup 22 and the tape roll 23 is provided. The container 25 is now closed by a cover member 29.

A schematically indicated air outlet 30 serves to connect a pump so that the interior of the container 25 can be evacuated. An inlet indicated only schematically by the reference numeral 31 is used to introduce a potting compound 32. The potting compound 32 is in particular a resin, for example a thermosetting one Two component epoxy resin. The potting compound 32 penetrates into the evacuated interior of the container 25 and can now fill all existing in the area of the tape roll 23 free spaces. For example, the potting compound 32 can penetrate into free spaces between two individual, adjacent winding layers 19 and possibly also into the smallest pores. The arrangement of the inlets and outlets 31, 30 is of course only to be understood schematically.

After curing of the potting compound 32, this provides the band wrap 23 enveloping body in the manner of a stiffening framework ready. Now, the lid member 29 of the container can be opened and the molded tape roll 23 are removed. Due to the aligned along the central longitudinal axis M mandrel 26, the molded tape roll 23 corresponding to a central inner recess which in the use state of the device 10 from the power supply line 12 according to the Figures 1 and 2 is penetrated. In this context, it should be noted that the presentation of the FIGS. 1 to 4 are not to scale to understand but in terms of their geometric relationships to illustrate the invention only in an illustrative manner.

The cast tape roll 23 can now by means of a diamond-tipped saw, alternatively, for example, by means of a water jet cutting machine, optionally with laser or plasma jet, along a cutting plane E, ie approximately along the plane of the paper Fig. 4 , are cut into two semicircular halves 16a and 16b. Of particular importance is that material areas of the potting compound 32 in the region of the annular end faces 34a and 34b of the tape roll 23 abut and prevent in this way a breaking of the winding layers 19 during cutting safe.

Usually, moreover, a material is chosen for the potting compound, which has a high glass transition temperature, advantageously above 100 ° C. In this way occurs even at such high, during the Processing generated temperatures no change in the stiffness of the potting compound.

After performing the dicing operation, the cut surfaces 33a, 33b (FIG. Fig. 3 ) advantageously provided with a cover, such as an adhesive strip or a paint. The very flat, smooth cut surfaces 33a, 33b are substantially free of fraying and protected by the attached, not shown cover from further damage.

The two now finished halves 16a, 16b of the substantially annular clamp 13 can now be mounted around a power supply line 12 around. For this purpose, usually separate fasteners, in the simplest case, an in Fig. 2 indicated adhesive strip 25 which provide a cohesion of the two parts 16 a, 16 b. Of course, screw connection elements od. Like. Provided, and optionally also cohesively-integrally formed as part of the potting compound 32 with.

In the circumferential direction u of the clamp 13, thus following the course of the winding layers 19, a nearly continuously continuous body is formed, which in each case has a gap 18 in the region of two joining regions 17 due to the divided, two-part arrangement. The gap 18 is not necessarily present due to the composite arrangement of the clamp 13 and is tolerated, but is essential in its meaning and affects the magnetic properties of the clamp 13 positively. In particular, by arranging a gap 18, a change of the characteristic of the device 10 becomes possible, in particular a flatter increase in the BH characteristic, whereby the danger of a saturation induction at very high currents is further reduced.

The gap 18 according to the invention has a width d in the range of about 10 microns and is filled with a non-conductive and non-magnetic medium, for example with paper. The gap 18 may also be formed as an air gap.

Claims (22)

1. Device (10) for the inductive coupling of electrical signals (PLC signals) to a voltage supply line (12) which is in particular current-carrying and is optionally provided with an insulating sheath (15), characterised by a substantially annular clip (13), which can be composed of at least two parts (16a, 16b), of nanocrystalline or amorphous, ferromagnetic material,
2. Device according to Claim 1, characterised in that the parts (16a, 16b) essentially extend along a circular arc.
3. Device according to Claim 1 or 2, characterised in that the clip (13) is composed of two substantially semicircular parts (16a, 16b).
4. Device according to any one of Claims 1 to 3, characterised in that the clip (13) is formed from a continuously annular wound web (23) which is divided into at least two parts (16a, 16b).
5. Device according to Claim 4, characterised in that the wound web (23) consists of a plurality of material layers (19, 20, 21) which are each of a thickness of several µm, for example 20 µm.
6. Device according to Claim 4 or 5, characterised in that the wound web (23) is cut along at least one plane (E).
7. Device according to Claim 6, characterised in that the wound web (23) comprises an impregnation like a casting compound (32) which is in particular applied prior to cutting.
8. Device according to Claim 7, characterised in that the casting compound (32) is a resin, in particular a thermosetting epoxy resin or a thermally stable polyester resin.
9. Device according to Claim 7 or 8, characterised in that the wound web (23) has been subjected to a vacuum prior to impregnation, and the casting compound has penetrated into free spaces, e.g. into pores, of the wound web.
10. Device according to any one of the preceding Claims, characterised in that the clip comprises a narrow gap (18) in the joining area (17) of each two adjacent parts in the assembled state.
11. Device according to Claim 10, characterised in that the gap (18) is filled with a filler, e.g. with air or with paper.
12. Device according to Claim 10 or 11, characterised in that the gap (18) is between 3 µm and 30 µm wide, in particular approximately 10 µm wide (thickness d).
13. Device according to any one of the preceding Claims, characterised in that the material has an initial permeability of at least 20000, in particular an initial permeability of approximately 40000.
14. Device according to any one of the preceding Claims, characterised in that the clip (13) comprises at least one fastening element (35) for connecting the parts (16a, 16b) together.
15. Device according to Claim 14, characterised in that at least one adhesive tape is provided as the fastening element (35).
16. Method for processing a substantially annular wound web (23) of nanocrystalline or amorphous, ferromagnetic material, characterised by the steps:

    a) introducing the wound web into a pot-like container (25),

    b) impregnating the wound web (23) with a casting compound (32),

    c) dividing the wound web (23) into at least two parts (16a, 16b),

    wherein the wound web (23) is impregnated at least in the area of the separation points.
17. Method according to Claim 16, characterised in that the container (25) can be evacuated, and the following step takes place between step a) and step b):

    d) subjecting the wound web (23) to a vacuum.
18. Method according to Claim 16 or 17, characterised in that the casting compound (32) consists of a resin, in particular of a thermosetting epoxy resin, e.g. a two-component epoxy resin, or of a thermally stable polyester resin.
19. Method according to any one of Claims 16 to 18, characterised in that the casting compound (32) has a glass transition temperature of above 100°C.
20. Method according to any one of Claims 16 to 19, characterised in that the following step takes place between step b) and step c):

    e) curing the casting compound (32), in particular at high temperatures.
21. Method according to any one of Claims 16 to 20, characterised in that step c) is carried out by means of a cutting device, in particular by means of a diamond saw or a water jet cutting device.
22. Method according to any one of Claims 16 to 21, characterised in that the following step is also carried out after step c):

    f) covering the cut faces (33a, 33b) of the wound web (23), for example by means of an adhesive tape or by means of lacquer.

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