FR2643496A1 - Multi-layer insulation for an electrical conductor, which includes, at least on the surface, a low-ductility metal or alloy, and method of manufacturing this insulation - Google Patents
Multi-layer insulation for an electrical conductor, which includes, at least on the surface, a low-ductility metal or alloy, and method of manufacturing this insulation Download PDFInfo
- Publication number
- FR2643496A1 FR2643496A1 FR8902231A FR8902231A FR2643496A1 FR 2643496 A1 FR2643496 A1 FR 2643496A1 FR 8902231 A FR8902231 A FR 8902231A FR 8902231 A FR8902231 A FR 8902231A FR 2643496 A1 FR2643496 A1 FR 2643496A1
- Authority
- FR
- France
- Prior art keywords
- layer
- powder
- conductor
- insulation
- thermoplastic polymer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F5/00—Coils
- H01F5/06—Insulation of windings
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
- H01F41/04—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing coils
- H01F41/12—Insulating of windings
- H01F41/122—Insulating between turns or between winding layers
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Superconductors And Manufacturing Methods Therefor (AREA)
Abstract
Description
Isolant multicouches pour conducteur électrique comportant au moins en surface un métal ou alliage peu ductile, et procédé de fabrication de cet isolant
La présente invention concerne un isolant multicouches pour conducteur électrique comportant au moins en surface un métal ou alliage peu ductile, ainsi qu'un procédé de fabrication de cet isolant. Elle s'applique en particulier aux isolants multicouches pour supraconducteurs électriques circulaires ou méplats, formés de brins torsadés et transposés constitués de filaments fins de matériau supraconducteur noyés dans une matrice entourée d'une couronne de métal ou alliage de résistivité élevée, notamment de cupronickel.Multilayer insulator for electrical conductor comprising at least a slightly ductile metal or alloy on the surface, and process for manufacturing this insulator
The present invention relates to a multilayer insulator for an electrical conductor comprising at least on the surface a metal or alloy which is not very ductile, as well as a method for manufacturing this insulator. It applies in particular to multilayer insulators for circular or flat electrical superconductors, formed of twisted and transposed strands made up of fine filaments of superconductive material embedded in a matrix surrounded by a crown of metal or alloy of high resistivity, in particular cupronickel.
Les conducteurs comportant en surface un alliage peu ductile présentent l'inconvénient par rapport aux conducteurs en cuivre ou aluminium qu'ils laissent supporter par leur isolation l'essentiel des efforts mécaniques auxquels sont soumis les éléments conducteurs électriques, tels que bobinages, barres Roebel, en lesquels ils sont assemblés. I1 peut donc se produire des décollements, des cassures ou des fissures de l'isolant, entraSnant des dangers de détérioration progressive de cet isolant, source de courts-circuits ou de mouvements de brins et d'accidents pour le personnel.Dans le cas des supraconducteurs, comportant des brins en matériau supraconducteur entourés d'une enveloppe de métal ou alliage de résistivité élevée, on estime généralement que le moindre déplacement d'un brin supraconducteur de l'ordre d'un micromètre peut suffire, sous l'effet de la conversion de l'énergie de frottement en énergie calorifique, à cntratner une élévation de température du conducteur conduisant à une transition de 1' étant supraconducteur à l'état résistif normal, et par là à rendre l'appareil ou la Tachine supraconductrice inapte à fonctionner. The conductors comprising a slightly ductile alloy on the surface have the drawback compared to the copper or aluminum conductors which they allow to be supported by their insulation for most of the mechanical stresses to which the electric conductive elements are subjected, such as coils, Roebel bars, in which they are assembled. It can therefore occur detachments, breaks or cracks in the insulation, causing dangers of progressive deterioration of this insulation, source of short circuits or strand movements and accidents for personnel. superconductive, comprising strands of superconductive material surrounded by a metal shell or high resistivity alloy, it is generally estimated that the slightest displacement of a superconductive strand of the order of one micrometer may be sufficient, under the effect of the conversion of the friction energy into calorific energy, to control a rise in temperature of the conductor leading to a transition from 1 being superconductive to the normal resistive state, and thereby rendering the device or the Tachine superconductive unfit to function .
La présente invention a pour but de procurer un isolant multicouches pour conducteur électrique comportant au moins en surface un métal ou alliage peu ductile, qui soit susceptible de résister à des contraintes mécaniques importantes, tant lors de sa fabrication que de son fonctionnement, sans apparition de décollements, de cassures ou de fissurations, ou dans lesquels des cassures ou fissurations apparues au cours de la fabrication se réparent spontanément par une sorte de cicatrisation, grâce à un certain effet de fluage de sa couche externe. Elle a encore pour but d'assurer lors de la cuisson du vernis un blocage mécanique de différents brins ou assemblages de conducteurs entre eux, ce qui permet dans le cas de brins supraconducteurs d'obtenir un conducteur supraconducteur multibrins mécaniquement stabilisé. The object of the present invention is to provide a multilayer insulator for an electrical conductor comprising at least on the surface a metal or alloy which is not very ductile, which is capable of withstanding significant mechanical stresses, both during its manufacture and during its operation, without the appearance of detachments, breaks or cracks, or in which breaks or cracks appeared during the manufacturing repair spontaneously by a kind of cicatrization, thanks to a certain effect of creep of its external layer. It also aims to ensure during the firing of the varnish a mechanical blocking of different strands or assemblies of conductors between them, which allows in the case of superconductive strands to obtain a multilayer superconducting conductor mechanically stabilized.
L'isolant multicouches selon l'invention est caractérisé en ce que sa première couche, au contact du conducteur, est en résine époxy chargée d'un matériau minéral inerte, et en ce que sa seconde couche est en un polymère thermoplastique non chargé, de température de fusion ou de ramollissement inférieure à celle de la première couche, déposé sous forme de poudre, puis homogénéisé par chauffage. The multilayer insulation according to the invention is characterized in that its first layer, in contact with the conductor, is made of epoxy resin loaded with an inert mineral material, and in that its second layer is made of an uncharged thermoplastic polymer, of melting or softening temperature lower than that of the first layer, deposited in the form of powder, then homogenized by heating.
I1 répond en outre de préférence à au moins l'une des caractéristiques suivantes - Le matériau minéral inerte de la première couche est l'oxyde de titane. It also preferably meets at least one of the following characteristics - The inert mineral material of the first layer is titanium oxide.
- Le polymère thermoplastique de la seconde couche est du polyvinylbutyral.- The thermoplastic polymer of the second layer is polyvinyl butyral.
Le procédé de fabrication de l'isolant multicouches de l'invention, dans lequel on dépose autour du conducteur la première couche de résine époxy chargée d'un matériau minéral inerte, est caractérisé en ce que l'on dépose autour de la première couche le poudre de polymère thermoplastique et en ce que l'on fait passer le fil ainsi revêtu à travers un four à une température au plus égale à 2500 C. The process for manufacturing the multilayer insulation of the invention, in which the first layer of epoxy resin loaded with an inert mineral material is deposited around the conductor, is characterized in that the first layer is deposited around the first layer. thermoplastic polymer powder and in that the wire thus coated is passed through an oven at a temperature at most equal to 2500 C.
Selon une première variante, on effectue le dépôt de la poudre de polymère thermoplastique par effet électrostatique. According to a first variant, the thermoplastic polymer powder is deposited by electrostatic effect.
Selon une autre variante, on effectue le dépôt de la poudre de polymère thermoplastique par passage du conducteur muni de la première couche à travers un lit fluidité de cette poudre. According to another variant, the thermoplastic polymer powder is deposited by passing the conductor provided with the first layer through a fluidity bed of this powder.
I1 est décrit ci-après, à titre d'exemple et en référence à la figure unique du dessin annexé, un procédé et un dispositif de dépôt d'une couche externe thermoadhérente d'un polymère thermoplastique sur un conducteur électrique déjà muni d'une première couche isolante en résine époxy chargée d'une poudre minérale. I1 is described below, by way of example and with reference to the single figure of the accompanying drawing, a method and a device for depositing a thermoadherent external layer of a thermoplastic polymer on an electrical conductor already provided with a first insulating layer of epoxy resin loaded with mineral powder.
La poudre minérale ajoutée à la résine époxy (comportant en outre un agent durcisseur phénolique) parait touer le rôle d'une entretoise entre les fils du conducteur, assurant ainsi le maintien d'un certain écartement entre eux. C'est de préférence de l'oxyde de titane, mais on peut également utiliser d'autres minéraux tels que l'oxyde de zinc, le sulfate de baryum, le carbonate de calcium, le mica, la silice, l'alumine ou des dérivés du zirconium. La proportion d'oxyde de titane est par exemple de 10 % en poids, et la grosseur de ses grains inférieure à 100 micromètres. The mineral powder added to the epoxy resin (further comprising a phenolic hardening agent) seems to play the role of a spacer between the wires of the conductor, thus ensuring the maintenance of a certain distance between them. It is preferably titanium oxide, but it is also possible to use other minerals such as zinc oxide, barium sulphate, calcium carbonate, mica, silica, alumina or zirconium derivatives. The proportion of titanium oxide is for example 10% by weight, and the size of its grains less than 100 micrometers.
Le conducteur 1 se déroule à partir d'un tambour de dérouleur 2. I1 passe de celui-ci par l'intermédiaire du frein 3 à un appareil de décapage aux ultra-sons 4 dans un bain de solvant mixte toluène-isopropanol. Ainsi nettoyé, le conducteur pénètre dans l'appareil de poudrage électrostatique 5, alimenté sous une tension de 40 Kilovolts. Une poudre de résine polyvinylbutyral chargée électriquement vient s'y déposer sur le conducteur chargé à une polarité opposée. The conductor 1 takes place from an unwinding drum 2. I1 passes from the latter via the brake 3 to an ultrasonic pickling apparatus 4 in a bath of mixed toluene-isopropanol solvent. Thus cleaned, the conductor enters the electrostatic powdering apparatus 5, supplied with a voltage of 40 kilovolts. An electrically charged polyvinyl butyral resin powder is deposited there on the charged conductor at an opposite polarity.
Le conducteur entouré de la couche de poudre de résine se rend alors au four de cuisson aux infra-rouges 6, dont l'atmosphère interne est à une température ne dépassant pas 2500 C. The conductor surrounded by the layer of resin powder then goes to the infrared baking oven 6, the internal atmosphere of which is at a temperature not exceeding 2500 C.
Bien qu'il soit difficile d'évaluer la température que prend le conducteur lui-même lors de sa traversée de ce four, on peut penser qu'elle reste notablement inférieure à celle de son atmos phère, de sorte que, même s'il s'agit d'un supraconducteur, ses propriétés supraconductrices ne sont pas altérées.Although it is difficult to assess the temperature that the driver himself takes when crossing this oven, we can think that it remains significantly lower than that of its atmosphere, so that, even if it is a superconductor, its superconductive properties are not altered.
Du four, le conducteur passe dans un bac de refroidissement à eau 7, puis à un cabestan de réglage de sa tension 8, à un organe de régulation des à-ooups de tension 9 et à l'enrouleur de stockage 10. From the oven, the conductor goes into a water cooling tank 7, then to a tension capstan 8, to a tension regulator 9 and to the storage reel 10.
La tension de claquage d'un fil revetu d'une couche thermoadhérente de 35 micromètres d'épaisseur selon l'invention était de 4,7 à 6 Kilovolts. I1 résistait à un essai de choc thermique d'une demi-heure à 2000 C. The breakdown tension of a wire coated with a thermoadherent layer 35 micrometers thick according to the invention was 4.7 to 6 Kilovolts. It withstood a half hour thermal shock test at 2000 C.
L'invention permet notamment la fabrication de bobinages à spires jointives ou non jointives, et l'assemblage du conducteur à partir de plusieurs brins supraconducteurs composites, dans le cas où chaque brin est diélectriquement isolé des autres. The invention allows in particular the manufacture of windings with contiguous or non-contiguous turns, and the assembly of the conductor from several composite superconductive strands, in the case where each strand is dielectrically isolated from the others.
Claims (6)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8902231A FR2643496A1 (en) | 1989-02-21 | 1989-02-21 | Multi-layer insulation for an electrical conductor, which includes, at least on the surface, a low-ductility metal or alloy, and method of manufacturing this insulation |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8902231A FR2643496A1 (en) | 1989-02-21 | 1989-02-21 | Multi-layer insulation for an electrical conductor, which includes, at least on the surface, a low-ductility metal or alloy, and method of manufacturing this insulation |
Publications (1)
Publication Number | Publication Date |
---|---|
FR2643496A1 true FR2643496A1 (en) | 1990-08-24 |
Family
ID=9378974
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
FR8902231A Withdrawn FR2643496A1 (en) | 1989-02-21 | 1989-02-21 | Multi-layer insulation for an electrical conductor, which includes, at least on the surface, a low-ductility metal or alloy, and method of manufacturing this insulation |
Country Status (1)
Country | Link |
---|---|
FR (1) | FR2643496A1 (en) |
Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2944235A (en) * | 1957-03-21 | 1960-07-05 | Melville F Peters | High temperature coil structure |
US3300843A (en) * | 1961-02-09 | 1967-01-31 | Furukawa Electric Co Ltd | Self-bonding magnet wire and method |
US3856566A (en) * | 1972-05-24 | 1974-12-24 | Gen Cable Corp | Method of making insulated magnet wire |
US4163826A (en) * | 1977-02-28 | 1979-08-07 | Sumitomo Electric Industries, Ltd. | Self-bonding magnet wires and coils made therefrom |
EP0008431A2 (en) * | 1978-08-25 | 1980-03-05 | Siemens Aktiengesellschaft | Process for insulating supraconductors in a magnetic winding |
US4231151A (en) * | 1978-10-03 | 1980-11-04 | Westinghouse Electric Corp. | Method and apparatus for manufacturing a filament served bondable conductor |
NL8001891A (en) * | 1980-03-31 | 1981-11-02 | Rea Magnet Wire Company Inc | Magnet wire with good winding and insertion properties - has a nylon-11 or nylon 12 top-coat having improved electrical properties in moisture environments |
US4388371A (en) * | 1981-06-29 | 1983-06-14 | General Electric Company | Self-bonding acrylic polymer overcoat for coated metal substrates |
US4614670A (en) * | 1985-07-25 | 1986-09-30 | Essex Group, Inc. | Method for insulating a magnet wire with an aromatic titanate modified nylon |
JPS63164413A (en) * | 1986-12-26 | 1988-07-07 | Mitsubishi Electric Corp | Oil filled electric apparatus |
-
1989
- 1989-02-21 FR FR8902231A patent/FR2643496A1/en not_active Withdrawn
Patent Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2944235A (en) * | 1957-03-21 | 1960-07-05 | Melville F Peters | High temperature coil structure |
US3300843A (en) * | 1961-02-09 | 1967-01-31 | Furukawa Electric Co Ltd | Self-bonding magnet wire and method |
US3856566A (en) * | 1972-05-24 | 1974-12-24 | Gen Cable Corp | Method of making insulated magnet wire |
US4163826A (en) * | 1977-02-28 | 1979-08-07 | Sumitomo Electric Industries, Ltd. | Self-bonding magnet wires and coils made therefrom |
EP0008431A2 (en) * | 1978-08-25 | 1980-03-05 | Siemens Aktiengesellschaft | Process for insulating supraconductors in a magnetic winding |
US4231151A (en) * | 1978-10-03 | 1980-11-04 | Westinghouse Electric Corp. | Method and apparatus for manufacturing a filament served bondable conductor |
NL8001891A (en) * | 1980-03-31 | 1981-11-02 | Rea Magnet Wire Company Inc | Magnet wire with good winding and insertion properties - has a nylon-11 or nylon 12 top-coat having improved electrical properties in moisture environments |
US4388371A (en) * | 1981-06-29 | 1983-06-14 | General Electric Company | Self-bonding acrylic polymer overcoat for coated metal substrates |
US4614670A (en) * | 1985-07-25 | 1986-09-30 | Essex Group, Inc. | Method for insulating a magnet wire with an aromatic titanate modified nylon |
JPS63164413A (en) * | 1986-12-26 | 1988-07-07 | Mitsubishi Electric Corp | Oil filled electric apparatus |
Non-Patent Citations (1)
Title |
---|
PATENT ABSTRACTS OF JAPAN vol. 12, no. 425 (E-681)(3272) 10 novembre 1988, & JP-A-63 164413 (MITSUBISHI ELECTRIC CORP.,) 07 juillet 1988, * |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4342814A (en) | Heat-resistant electrically insulated wires and a method for preparing the same | |
CA1177921A (en) | Electromechanical cable resistant to high temperatures and pressures, and process for making same | |
US5861578A (en) | Electrical conductors coated with corona resistant, multilayer insulation system | |
CA2312883C (en) | Abrasion resistant coated wire | |
EP2040267B1 (en) | Electric cable resisting the propagation of an electric arc | |
EP2557572B1 (en) | Electric cable resistant to partial discharges | |
EP0596791A1 (en) | Superconducting winding, in particular for current limiter and current limiter with such a winding | |
JP2827333B2 (en) | Manufacturing method of heat-resistant insulating coil | |
GB2046501A (en) | Heat-resistant insulated electric wires and coils and methods of making and connecting such wires | |
US4109375A (en) | Method of making adhesive coated electrical conductors | |
EP3358575B1 (en) | Electric cable resistant to partial discharges | |
FR2643496A1 (en) | Multi-layer insulation for an electrical conductor, which includes, at least on the surface, a low-ductility metal or alloy, and method of manufacturing this insulation | |
US3006794A (en) | Articles of manufacture such as electrical coils and method of producing the same | |
US4276102A (en) | Method for compacting transposed cable strands | |
US3273225A (en) | Method of making electromagnetic structures for high-temperature service | |
EP2808874B1 (en) | Electric cable including at least one electrically insulating layer | |
US4274895A (en) | Method of manufacturing a flexible electric cable which has a tinned stranded conductor on which an insulation is applied at a high temperature | |
JPH0125166B2 (en) | ||
EP0568415B1 (en) | Insulating method of an electrical conductor and insulated electrical wire obtained by this method | |
US3365688A (en) | Electromagnetic structures for hightemperature service | |
DE2342070C3 (en) | Process for the production of a winding insulation for an electrical machine that is suitable for permanent temperature loads above 250 C | |
JP2826740B2 (en) | Manufacturing method of glass insulated wire | |
US3015686A (en) | Article of manufacture utilizing a stranded core construction and method of making | |
CN218602156U (en) | Enameled wire with high PDIV bilateral super-thick paint film | |
JPS6362041B2 (en) |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
ST | Notification of lapse |