WO2012095321A2 - Device for improving the electrical properties of a coating of a conductor or the like by insulating materials, and method for using said device - Google Patents

Abstract

The invention relates to a device for improving the dielectric strength of an insulating substrate on the surface of an electric conductor, a device being mounted downstream of the coating device of the conductor, which device achieves an alignment of the molecules and/or nanoparticles or the like of the still liquid insulation substrate by exposing the device to a high voltage. The invention also relates to a method for using said device, whereby a symmetric anisotropic alignment of the molecules and/or nanoparticles or the like in the device is carried out.

Description

 Device for improving the electrical

Characteristics of coating a conductor or the like with insulating materials, and a method of using such a device

The invention relates to a device for improving the electrical properties of a coating by means of an insulating material on the surface of conductors for electrical use, and to a method of using a liquid insulating material on surfaces of conductors for electrical use by such a device. DD 281 314 A7 discloses a process for the electrical coating of parts which are completely or partially electrically conductive. Such a coating composition consists of any polymers that may be mixed with fillers, or inorganic suspensions that can be applied uniformly to parts by the coating thickness and duration is adjustable by selecting the process parameters. In this case, at least one solvent and a highly dispersed hydrophobicized silica have been added to the coating composition, so that the silica in combination with the solvent under the influence of the electric field on the

CONFIRMATION COPY Coating part is deposited and there builds a stabilizing framework for the coating composition.

WO 02/36 851 A1 describes a method and a device for the surface treatment of electrically insulating substrates, which are used to coat substrates.

DE 103 20 805 B4 discloses a device for processing cylindrical, at least one electrically conductive vein having substrates with a process space and by applying a voltage to at least one, the process space associated, fixedly disposed on the device electrode and a counter electrode, wherein in A plasma is ignitable in the process space and the applied voltage is an AC voltage.

Insulating materials whose basic components consist essentially of polymers or the like applied on a surface of a conductor or the like often do not have sufficient insulating strengths. This inevitably leads to creeping and sliding discharges. Such low insulation resistance is characterized by the fact that a non-self-contained, homogeneous insulation barrier is present. In this case, the dielectric strength of an insulating material corresponds to an electric field strength which may at most prevail in the conductor, without there being a voltage breakdown. Known paint layers of electrical conductors or the like have an isotropic surface with respect to their molecules or the like.

In the art, particles with a particle size that move in the nanoscale (nanoscale particles) have an increasing Application found. This also applies to dispersions containing particles with magnetic or ferroelectric properties.

For example, transformers consist of a magnetic circuit with a ferrite or iron core around which the corresponding conductors of various circuits are wound so that the current of each circuit is passed around the core several times. In this case, such transformers work according to the induction principle, this consists of a magnetic flux that generates a magnetic field. In an ideal transformer, the voltages on the windings due to the electromagnetic induction are proportional to the rate of change of the magnetic flux and the number of turns of the winding. In order to increase the magnetic induction, transformers ideally have cores.

The inductance is an electrical property of a current-carrying conductor, where due to a change in the electric current, a magnetic field is built up.

The object of the invention is to increase the breakdown and dielectric strength in the low and high-frequency voltage range of insulation in electrical conductors, such as wires, cables or the like. Furthermore, a lower damping effect should occur in the high-frequency range in the case of the conductors or the like. The invention should lead to a reduction of the process times and a reduced use of insulating materials. In addition to increasing the dielectric strength should also be possible to increase the line inductance of the electrical conductors, so as to build the inductors made from the conductors, transformers or the like, for example, to make smaller or more powerful. The object of the invention is achieved by a device according to claim 1 and by an insulating substrate according to claim 6 and a method according to claim 7 for the realization. The subclaims have a further embodiment of the solution principle of the invention to the content.

There is therefore proposed a device for improving the electrical properties of a coating of an insulating substrate or one or more paint layers on the surface of conductors for electrical applications, such as wires, or the like with a coating device for applying a liquid insulating substrate, the orientation of the isotropic molecules and / or nanoparticles or aggregates of the still liquid insulating substrate achieved by application of a high voltage by the device according to the invention. In this case, the conductor is continuously moved through the device, so that at the end of the device, a curing of the insulating substrate with simultaneous alignment of the molecules and / or nanoparticles or the like has taken place. By the electric field of the high voltage or a field strength, a symmetrical alignment, preferably in the tangential direction of the molecules or the nanoparticles or the like is carried out so that the surface of the insulating material assumes an anisotropic structure. By means of the targeted alignment of the molecules or the like, virtually a closed surface of the insulating substrate is achieved without requiring thickening of the insulating layer. Depending on the use of the conductors, no additional insulation materials or aggregates are necessary. Already without addition of additives in the insulating substrate much larger dielectric constants can be achieved. By a repeated application of the method, that means there are several Insulating substrate layers applied to each other, the electrical strength increases in addition to other mechanical properties of the electrical conductor. The inventive method can also be applied to so-called baked enamels.

To increase the dielectric strength, it is possible to provide the insulating substrates used with certain, particularly effective additives in the form of paint fillers. Barium titanate or strontium titanate or mica or serpentine or fiber glarpentine or glass fibers or aluminum oxide or the like have proven to be particularly suitable additives. It is also possible to use all non-expressive effective additives.

The addition of additives to the insulating substrates already increases the dielectric strength to a known extent. By incorporating the aggregates, which in particular have a platelet geometry in the molecular range, an alignment by treatment with a high voltage is achieved by a method according to the invention to be described. This means that the isotropic orientation of the platelets is converted into an anisotropic alignment of the platelets in one direction due to the applied high voltage, which is designed as a DC voltage. Spherical particles are less suitable for such use, because thereby the degree of coverage of the conductor surface is not optimal. It remain between the individual spherical molecules to large gaps. For this reason, it is important to obtain the appropriate additives through a chemical process in the desired optimized form. Due to the geometry of long-formed molecules and the orientation by the high-voltage treatment during the hardening process, the dielectric strength improves over 50% over conventional applications. This means that different additives can be used for different electrical uses of the conductor wires. Si, for example, for the thermal conductivity of a different additive than, for example, an additive to increase inductances or dielectric strength necessary.

Aggregates of any kind change the properties of the insulating substrate quite decisively with the high-voltage process according to the invention. The varnish used as the insulating substrate is usually a polymer. Such a lacquer layer with its molecules is isotropic, this applies to any type of insulating substrates. Alone by the application of a high-DC voltage created by the process according to the invention, an alignment of the molecules or the like in an anisotropic arrangement. This anisotropy means a closed or close to closed surface. A completely closed surface is achieved by several insulating substrate layers one above the other, d. H. the process of coating is repeated several times. This is already the case today. However, by the invention it is possible to align the molecules horizontally and thus achieve a higher degree of coverage and thus a higher dielectric strength.

Even today, paint coatings of conductors or the like are carried out with an insulating substrate in multiple layers to ensure a uniform quality. This may be a whole number of layers depending on the use of the conductor. By the invention, however, it is possible to achieve a lower paint usage, because the number of paint layers may be lower due to the aggregates. This means not only a saving of paint quantities but also lower process times. Also, the coating of the conductor mechanically stable, ie it can be bent more. At the same time, however, this also means that the paint does not peel off, which is certainly the case with very thick layers of paint in the usual manner of application.

The proportion of aggregates depends on the desired use. Aggregates up to about 40% are to be mentioned as the upper limit, because in addition the molecules can only be aligned insufficiently by the process according to the invention. This is because the individual molecules or the like are enveloped by the insulating substrates, so that there is no grain contact against each other. In the electrical properties, it is not important that the surface is completely closed by a paint layer alone by the molecules in the aligned state. Due to the multiple application, d. H. in several layers on top of each other, the problem of holes is repaired.

A conductor surface produced by the method according to the invention requires substantially less coating layers than conventionally produced surfaces. This has the consequence that the use of material is lower and this also leads to a reduction of the process times, at the same time significantly improved electrical properties. The insulating material is mechanically stable by the method according to the invention, because it can be subjected to greater mechanical stress, without changing its achievements and exceed. A faster processing is also possible.

The molecules or macromolecules or nanoparticles usually present in the insulating substrate have a heterogeneous state of an isotropic molecule composite. By the application of a High voltage to the device, which consists essentially of a helix with at least two electrical conductors, an aligned homogeneous dressing is achieved with a self-contained anisotropic surface of the not yet solidified (hardened) insulating material, which is retained after curing.

In a further preferred method, it is possible that the electrical properties are increased in terms of their self-inductance. These nanoparticulate ingredients of the insulating substrate do not increase the dielectric strength. Rather, they serve to increase the inductance and to enhance corresponding magnetic properties. Thus, it is possible, depending on the use of the electrical conductor here to cause a higher line inductance than only pure copper or aluminum conductors or the like. This results in that electrical components that can be built much smaller with such wires, which include an increased line inductance. In addition to the already mentioned transformers, these include corresponding windings for motors or generators. The molecules or ferritic nanoparticles present in the insulating substrate also have a heterogeneous state within the liquid insulating substrate. By applying a high voltage to the device according to the invention, which consists essentially of a helix with at least two electrical conductors, a directed homogeneous bond is achieved with a quasi-closed anisotropic surface of the not yet solidified insulating material, which remains after curing.

Depending on the desired use of the conductors coated by the method according to the invention, it is possible for them to be used directly or pass indirectly through several coating lines without the hardened layers losing their anisotropic structure.

Thus, it is possible that the ferritic nanoparticles are also exclusively alone depending on the use of the conductor, introduced into the paint and can be aligned accordingly. By way of the invention, however, it is also possible that different layers can be applied to a conductor both to increase the dielectric strength and to increase the line inductance.

The coils, the at least two conductors, are in a preferred embodiment progressively spaced apart, d. H. they are wound gradually progressively narrower. This achieves a "creeping" alignment of the isotropic molecular structure or the like into an anisotropic structure.

In a further preferred embodiment, it is possible that the at least two electrical conductors are executed in opposite directions with a progressive pitch. A possible construction of the device for the anisotropic alignment of the molecules or the like in the paint can be constructed, for example, such that the at least two conductors are applied on a silicate tube in progressive or approximately equal distances on the outside diameter. The inner diameter of the tube is dimensioned so that the provided with the paint insulation conductor passes without contact with the pipe. For safe high voltage insulation, another tube or body includes the silicate tube with the coils, the sealed space between the outer tube and the inner tube being filled with an insulating oil. In a further preferred embodiment, it is also possible to make this gap with a suitable insulating resin or the like high voltage resistant. At the ends of the sealed pipes or the like, there are the high voltage electrical connections provided by a power supply allowing a continuous change in the high voltage. The entire device is held by a holder.

The device may also be referred to as a dipole, wherein the corresponding device may also consist of a quadrupole. The applied high voltage, which is preferably a DC voltage, depends on the dielectric strength of the insulating substrate used on the conductor to be coated or the like.

By applying the high voltage to the device described above, the anisotropic surface of the coating of the conductor is reached, resulting in that the previously existing disorderly isotropic structure of the molecules or the like is virtually closed with their gaps. By the inventive device and the method used therewith, a targeted alignment of the molecular structure or the like of the insulating material is achieved. This means that an internal and external uniform surface is achieved by the molecular structure, which has significantly fewer defects than a normal common surface coating of electrical conductors or the like. In this case, an electrical as well as a mechanical improvement of the coating is achieved. Depending on the desired use of the conductors coated according to the method of the invention, it is possible for them to pass directly or indirectly through a plurality of coating sections without the hardened layers losing their anisotropic structure. In a further preferred embodiment, it is possible that the device described above, the coating subsequent to the part of the Coating plant is. In such a case, for example, an immersion bath would cause the molecules to be aligned within or after the bath. By the above-described procedure of the method in connection with the device, an increase in the coating thickness is avoided, so that, for example, in insulated wires when used on winding bodies, a higher filling factor is achieved with a simultaneous increase in the dielectric strength.

By means of the invention, a substantially better conductor surface and thus an increase in quality of the product with a smaller outside diameter, less process costs and shorter processing time are achieved.

Furthermore, the invention is characterized in particular by the fact that a significant increase in the dielectric strength in the low-frequency range is achieved. At the same time, however, a low-loss filter and damping effect is achieved even in the high-frequency range. However, this also applies to the dielectric strength and the mechanical behavior in the HF range.

In order to achieve the same or significantly improved dielectric strength in wires, a much lower material usage is necessary by the invention. This means that insulating coatings are saved to a great extent, because significantly less insulating layers must be applied one above the other. This gives the paint a better quality, because fewer defects are included. At the same time, however, this also means that the process times of the coating can be reduced.

Claims

claims Device for improving the electrical properties of a coating by means of an insulating substrate on the surface of conductors for electrical applications, such as wires or the like with a coating device for applying the liquid insulating substrate on the surface of the conductor or the like, characterized in that the device downstream of the coating device which achieves alignment of molecules and / or nanoparticles and / or additives of the uncured insulating substrate by applying high voltage to the device, the conductor or the like being moved continuously through the device, and of an isotropic molecular arrangement and / or nanoparticle arrangement and / or aggregate arrangement becomes an anisotropic molecular arrangement or the like. Apparatus according to claim 1, characterized in that the device consists essentially of a helix, consisting of at least two electrical conductors, which surround the same direction or in opposite directions with a progressive slope through the moving coated conductor by means of a distance. Apparatus according to claim 1 or 2, characterized in that the distances between the at least two filaments of the electrical conductors of the device to the end of the device are narrower, and kept distant by means of a holder. Device according to one of the preceding claims, characterized in that the device consists essentially of a silicate tube or the like with applied coils, through which the conductor to be processed or the like is passed, and that the silicate tube or the like is surrounded by a spaced body, the filled with an insulating oil or an insulating resin. Device according to one of the preceding claims, characterized in that a plurality of the molecular alignment or the like serving devices are connected in series or used individually to achieve multiple layers of paint on the conductors or the like. An insulating substrate having a molecular structure and / or aggregates and / or ferritic nanoparticles to provide a homogeneous substantially closed solid surface of an electrical conductor. A method of using a liquid insulating substrate according to claim 6 on surfaces of conductors for electrical use, by means of a device having an inlet and an outlet for the continuous, coated conductor or the like, wherein anisotropic orientation is applied by applying a high voltage to the device of isotropic molecules and / or ferritic nanoparticles and / or aggregates after coating the conductor on the liquid insulating substrate prior to solidification in a continuous process. 8. The method according to claim 6 and 7, characterized in that a symmetrical alignment of the molecules and / or nanoparticles or the like of the conductor is carried out in the device. A method according to claim 6, 7 and 8, characterized in that an alignment of the molecules and / or ferritic nanoparticles and / or the aggregates in the device by applying a rectified high voltage and / or a magnetic field is achieved. 10. The method according to any one of claims 6 to 9, characterized in that the method for coating with subsequent alignment of the isotropic molecular and / or aggregates and / or the ferritic nanoparticle composite repeatedly to a directed homogeneous anisotropic composite in a conductor or the like becomes.