US3595982A - Supercounducting alternating current cable - Google Patents

Supercounducting alternating current cable Download PDF

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US3595982A
US3595982A US784809A US3595982DA US3595982A US 3595982 A US3595982 A US 3595982A US 784809 A US784809 A US 784809A US 3595982D A US3595982D A US 3595982DA US 3595982 A US3595982 A US 3595982A
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helium
conductor
cable
cable according
disposed
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Wilhelm Kafka
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Siemens AG
Siemens Corp
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Siemens Corp
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B12/00—Superconductive or hyperconductive conductors, cables, or transmission lines
    • H01B12/14—Superconductive or hyperconductive conductors, cables, or transmission lines characterised by the disposition of thermal insulation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
    • Y02E40/60—Superconducting electric elements or equipment; Power systems integrating superconducting elements or equipment

Definitions

  • a superconducting alternating current cable has a space for conducting a fluid of insulating helium and a carrier member for conducting a fluid of cooling helium.
  • the carrier member maintains the insulating helium separate from the cooling helium, the insulating helium being kept at a pressure different from that of the cooling helium.
  • SUPERCONDUCTING ALTERNATING CURRENT CABLE My invention relates to superconducting cables and more particularly to superconducting cables wherein helium is used as a cooling as well as an insulation medium.
  • Superconducting alternating current cables are known in various configurations one of which has superconductors with an electrical insulation of solid dielectric material between the conductors of different voltage. The heat insulation is disposed outside the electrical insulation. Cooling is effected by liquid helium which removes the heat resulting from alternating current losses in the conductor and eddy current losses in normal-con ducting metals insofar as they occur within the heat insulation as well as losses developed by mechanical alternating forces and dielectric losses which appear within the electrical insulation. Also removed in this way is the heatwhich penetrates the heat insulation.
  • each current conductor is provided with a tubular carrier equipped with a thin outside layer of niobium and is cooled from within by liquid helium.
  • the current conductor is surrounded by heat insulation and then enclosed by an electrical insulation of solid insulating materials, the latter being at room temperature. With this arrangement, the dielectric losses are dissipated directly to the surrounding.
  • the heat insulation must transmit the magnetic forces between the conductors, and because of itsless than ideal elasticity, certain losses will be produced by the alternating forces and will occur, for the most part, at low temperatures. Because the heat insulation must be more stable than in the first referred to configuration in order to transmit the magnetic forces, it has a relatively high heat conductivity. However, this configuration too has other disadvantages which have heretofore prevented its practical utilization. For example, the heat insulation requires substantial space which makes the electrical insulation expensive. Also, the capacitance of such cables is very high while the wave propagation velocity is small which renders its use in transmitting over great distances impractical.
  • a three-phase cable has four tubular conductors coaxially disposed with respect to each other and each conductor comprises a carrier tube having a niobium layer.
  • the inner and the outer tubular conductors each serve as a conductor for one phase of the three phase current and the third three-phase current is guided across the other tubular conductors which are positioned between the inner and the outer conductors and are separated by a vacuum chamber which provides a thermal insulation.
  • liquid helium is provided which is simultaneously used to cool the tubular conductors.
  • the helium is conducted into the space between the inside conductor and the adjacent first conductor for the third phase in one direction along the cable axis and returned in opposite direction via the intermediate space between the second conductor for the third phase and the outer conductor which surrounds the second conductor.
  • great care must be taken to ensure that no gas bubbles will occur in the helium while the heat is being removed which impair the effect of the insulation, or if gas bubbles do occur, that the helium will withstand the full peak voltage between the tubular conductors.
  • This requires a very high helium throughput or a very high pressure in the helium.
  • this has associated with it the disadvantage of requiring a considerable expenditure for cooling and a costly construction of the cable.
  • the vaporcooling method which is preferable in connection with helium cannot be employed.
  • I provide a cable wherein the helium which serves as an insulating medium and the helium which serves as a cooling medium are separated from each other and are maintained at different pressures.
  • Liquid helium in particular can be used as an insulation means and subjected to higher pressures than the helium which serves as a coolant.
  • the higher pressure in the insulation space prevents evaporation of the liquid helium which serves as an insulation means and also prevents the formation of gas bubbles therein. Consequently, the insulation has a high dielectric strength. Due to the somewhat higher temperature in the insulation chamber containing the liquid helium, the difference in pressure should be appropriately great, and may amount, for example, to 0.5 to 5 atmospheres.
  • the spaces provided for receiving the insulating helium are connected at the cable ends or at several places along the cable to pumps or pressure bottles equipped with reducing valves.
  • gaseous helium may be used as an insulating medium which is under a lower pressure than that of the flowing, liquid and evaporating helium which serves as a coolant.
  • the lower pressure in the insulation space prevents a condensation or droplet formation of the gaseous helium which serves as an insulating medium. Since the latter may not be colder than the helium which serves as a coolant, condensation of the gaseous helium is impossible.
  • This type of insulation is especially preferred in superconducting communication cables in which condensation and droplet formation can cause undesirable changes of line constants along the length of the cable.
  • spacers of solid insulating material are provided between conductors of different potentials for maintaining the intermediate space filled with the insulating helium.
  • the space holders are preferably made of synthetic material having a low dielectric loss factor and are so spatially arranged that their volume constitutes only a small fraction of the entire intermediate space which serves as an insulator.
  • Suitable plastics are, for example, polyethylene, polytetrafluorideethylene and polystyrol.
  • a preferred construction for a space holder disposed between a tubular outer conductor or a tubular sleeve which encloses the insulating helium and a concentrically positioned inner conductor is a thread of plastic having a low dielectric loss factor, such as polytetrafluoride-ethylene.
  • the plastic is shaped as a screw spring and is wound around the inside conductor in the shape of a spiral.
  • the pitch of the thread in the screw spring preferably approximates or is equal to the diameter of the screw spring.
  • the average, relative dielectric constant e of the electrical insulation is important for calculating the cable capacitance.
  • the dielectric losses may be calculated in a similar manner with a median dielectric loss factor tan 8.
  • the dielectric loss factor for liquid helium is not exactly known, but it may be assumed to be less than 10'.
  • Polyethylene probable has the smallest losses of all synthetic materials, however, it is not certain whether it maintains enough elasticity at 4 to 5 K.
  • the usage of polytetrafluorideethylene is preferred, the material not being brittle even at low temperatures.
  • the dielectric loss factor, tan 6, for gaseous helium and polytetrafluoride-ethylene is smaller than 5X10 and for liquid helium and polytetrafluoride-ethylene, tan 8 smaller than 5.95Xl.
  • Approximately percent of the volume of polytetrafluoride-ethylene is assumed to have a dielectric loss factor of about 10". In estimating the economy of a cable, the primary factor to be considered is the ratio of the dielectric loss to the rated output.
  • the rated output P cannot be arbitrarily increased beyond the natural output of the cable when energy is transmitted across a distance of more than 5 percent of the wave length of the current to be transmitted, because otherwise, the inductive voltage drop along the cable will become too great. Therefore, the ratio of the dielectric losses to the natural output P /P can be con sidered to be a criteria of economy.
  • Typical of a cable which uses gaseous helium as an insulation medium and spacers of polytctrafluoride-ethylene is a product 5.15Xl0'.
  • the product is 6.3X10', and for a cable using a solid polytetrafluoride-ethylene insulation, the product is 1.48X 10".
  • it is therefore 23 times larger than when liquid helium is used to form the insulation and 29 times larger than when gaseous helium is used.
  • the difference may be further increased if it becomes possible to produce the space holders of polyethylene with tan 8 l0. This polyethylene having a small loss factor seems to be unsuited for use as a solid insulation because of cracks which form during the coolingprocess.
  • the voltage reliability of the cable using a helium insulation against short term voltage peaks can be further increased by providing, in addition to the helium insulation, a solid insulation comprised of a synthetic material with a small dielectric loss factor, which during normal operation, takes over only a small portion of the voltage and thus has only small dielectric losses but which has the capability of taking over the full voltage peak for a short period during a breakdown of the helium insulation. After a disappearance of the voltage peak, the breakdown through the helium too disappears and the cable has again the same low loss as before.
  • An additional insulation of this type may be arranged directly below the outer conductor, when a pair of coaxial conductors is involved.
  • a number of thin plastic foils for example, of polytetrafluorideethylene are wound with overlapping edges upon the spacer, and only then is the outer conductor applied. Since the dielectric strength of the ploytetrafluoride-ethylene foils is essentially greater than that of the gaseous or the liquid helium, a thin layer suffices, which, due to its greater dielectric constant, takes over only a small fraction of the voltage during operation and causes only small losses.
  • the magnitude of the cooling device depends not only on the dielectric losses but also on the influx of heat and, thus, on the diameter of the cable.
  • the ratio d,,/d determines the wave resistance and the capacitance of the cable and can therefore not be arbitrarily reduced.
  • d diameter of the outer conductor, d diameter of the inner conductor.
  • the outer cable diameter therefore depends on the diameter d, of the inside conductor.
  • the cable comprises on or several conductor pairs having an inner conductor and a tubular outer conductor which encloses the inner conductor.
  • the space between the inner conductor and the outer conductor is filled with helium which serves as insulation, while at the outside of the tubular outer conductor, helium is circulated which serves as a coolant.
  • the inner conductor may be shaped as a wire, for example, but a tubular design is preferable, so that it can conduct liquid helium serving as a coolant.
  • the cable may also be built up of several parallel, cylindrical conductors, rather than coaxial conductor pairs.
  • each conductor is concentrically arranged in a tube of poorly conducting metal or plastic material which encloses the conductor so as to be spaced a determined distance therefrom. The distance is maintained by spacers as I in the case of coaxial conductor pairs.
  • the intermediate space between conductor and tube is filled with helium which serves as an insulating medium whilc liquid helium surrounds the outside of the tube and serves as a coolant.
  • the conductors are preferably tubular in shape so that they can conduct liquid helium acting as a coolant. Three such conductors can form a three-phase current system.
  • the superconductor is preferably provided only in form of a thin layer disposed on a carrier comprised of metal or insulating material.
  • soft superconductors such as niobium or lead have no alternating current losses.
  • the current penetrates only to a depth of approximately 10" cm.
  • the hard superconductors are only used in the form of very thin layers or loaded to a value far below their critical current density. Thin layers of superconductors may be produced by vapor disposition, galvanic precipitation and other known methods.
  • superconductors may be applied on a foil which is then placed around a conductor carrier or the spacer without pitch.
  • superconductors may be in the form of lead wires or tubes, a separate carrior not being required.
  • the heat insulation must not be compressed, it is advantageous when laying the cable to divide the outer, vacuumtight pressure conduit along its length and to insert the pipe for the cooling helium together with the heat insulation and the intermediate shield from above into the lower portion of the pressure conduit.
  • the pipe is held within pressure conduit by wires having a poor thermal conductivity.
  • the upper portion of the pressure conduit is subsequently applied and a tight vacuum is ensured by welding or soldering an outer skin of, for example, steel, placed around the pressure conduit.
  • the conductor pairs or the three-phase systems may be pulled into the pipe through which the cooling helium passes at the site where the cable is to be situated.
  • outside pressure conduit Since the outside pressure conduit is not subjected to a temperature change and does not contract, tensions or longitudinal displacements occur between this conduit and the inner pipes. This condition can be avoided by arranging the inner pipe which holds the liquid cooling helium into a snakelike shape which stretches to form an almost straight line during the cooling off process. The outside pressure conduit must then provide room for these snakelike configurations. It is particularly preferred to also arrange the outer pressure conduit into a snakelike form having a high up curvature less than that of the pipe holding the cooling helium at room temperature, that is, prior to the cooling process.
  • the heat insulation and cooling arrangem'ent of a high-current cable of the present invention with communication cables.
  • the high-current conductors do not influence the communication conductors at all, if they are built up as coaxial conductor pairs of soft superconductors and the outer conductor is grounded. Since the diameters of the communication conductors are considerably smaller than the diameters of the high-current conductors, they may be pulled into the spaces between the high-current conductors. Although the intermediate spaces offer less room for the cooling helium, no disadvantage is presented, rather, this affords an advantage because along hilly terrain where the cable will be inclined which prevents the cooling helium is prevented from flowing away rapidly.
  • the cable is subdivided into as many three-phase subsystems as there are feeding points provided in the distribution network.
  • the ends of the partial cables lying at one end of the cable are connected with the power installation and the other ends of the partial cables are connected with spatially distributed feeding points of the distribution network to be supplied by the power plant.
  • a network fed by a power station having a capacity of 1000 MW., the short circuit power would have an order of magnitude of l0,000 MVA., if the central feeding is via conventional cables.
  • the cable of the invention By subdividing the cable of the invention into l0 subconductor systems, it is possible to reduce the short circuit power at each feed point to 400 MVA.
  • the low transmission voltages of the cable of the invention make it possible to operate only with, for example, 20--30 kv., without transformation, from the generator of the power plant to the network being supplied.
  • the transmission constants of such cables resemble more those of a multiple overhead' line than those of conventional cables.
  • the -line resistance is however zero and the leakage is slight. Therefore, the cables of the invention are well suited for transmission over great distances.
  • the superconductors it is not necessary to give the superconductors such a dimension that they can withstand the full short circuit current in the superconducting state. It is satisfactory that the superconductors do not yet pass from the superconducting into the normal conducting state at such current values which are expected of the cable without disconnecting that is, at currents which exceed the rated current by approximately 50 percent. Still larger currents will be cut off, as soon as possible in view of the other parts of the distribution network.
  • the cable can be constructed, without any particular enlargement, so that the short circuit current is received by the normal conducting carrier of the superconducting layers for the time prior to disconnection. It is preferable to fabricate these carriers from relatively pure metal because then the resistivity will then be especially low at a low temperature and the short circuit current will cause fewer losses. In case of frequent short circuits and rapid reclosing, an enlargement of the cooling plant for the recycled helium may be required.
  • FIG. I is a side view, partially in section, of an embodiment of a transmission line of the invention equipped with a spiral spring spacer.
  • FIG. 2 is a view partially in section of the transmission line of FIG. '1 taken along the line n41.
  • FIG. 3 is a side view, partially in section, of an embodiment of a transmission line of the invention equipped with conical sleeve spacers.
  • FIG. 4 is a view partially in section, of the transmission line of FIG. 3 taken along the line IV-IV.
  • FIG. 5 is a sectional view of a cable having six coaxial conductor pairs.
  • FIG. 6 is a sectional view of a three-phase system having three parallel, noneoaxial conductors.
  • FIG. 7 is a longitudinal section through an outer pressure conduit in which a pipe for the cooling helium is mounted, the pipe being illustrated having the snakelike configuration when being mounted.
  • FIG. 8 is a schematic representation of a city feeder system fed from a distant power installation having short circuit power which is limited.
  • FIG. 9 is a side view, partially in section, of an embodiment of the cable according to the invention wherein the tubes carrying the superconductors are made ofinsulating material.
  • FIG. 10 is a view partially in section of the transmission line of FIG. 9 taken along the line IXIX.
  • FIGS. 1 and 2 show a coaxial pair of conductors wherein reference numeral 1 designates the inside conductor.
  • the coaxial pair consists of a thin superconducting layer 8 of pure niobium on a tape-shaped foil 9 of 99.9 percent pure aluminum.
  • This tape-shaped foil is placed around the carrier pipe 2 of pure aluminum or wound around it in turns of very high pitch with the superconducting layer facing outwardly.
  • Helices ofa spiral spring 3 are wound about the inside conductor to form a spacer.
  • the spiral spring is comprised of threads of polytetrafluoride'ethylene.
  • the outside conductor 4 is wound about he spacer in the form ofan aluminum band 10 having a superconducting layer 11 disposed so that the superconducting layer faces inwardly.
  • the space 5 formed by the inner and outer tubes constitutes a conducting means for helium which serves as an insulating agent.
  • the liquid helium which acts as the coolant passes through the inside chamber 7 of the carrier pipe 2 and surrounds the outer side of the tube 6.
  • FIGS. 9 and I0 A configuration similar to that shown in FIGS. I and 2 is shown in FIGS. 9 and I0 wherein the numerals correspond to the same materials as in FIGS. I and 2 except that the carrier pipe 6 and the tube 2 of the latter are depicted as made of insulating material and have the reference numerals 7] and 72 respectively.
  • FIGS. 3 and 4 illustrate another form of the spacer.
  • Slotted, conically formed sleeves 13 made of synthetic material are alternately pushed upon the inside conductor I from different sides.
  • openings I4 have been provided in the sleeves.
  • the spacer is provided with a slot 15 which is used for mounting the spacer upon the inside conductor ll.
  • These spacers can contract freely during cooling in tangential and axial direction and will not suffer critical strains.
  • the spacers are easy to produce since they are not required to absorb any electrical forces. Rather, the spacers support only the weight of the inside conductor l and the carrier pipe 2 with the cooling helium contained therein.
  • a thin wrap 16 of insulating material having a low dielectric loss factor is disposed between the spacer l3 and the superconducting layer 11.
  • FIG. 5 illustrates the cross section of a cable with six coaxial conductor pairs 21 which are of the same construction as the conductor airs shown in FIGS. 1 and 2 or FIGS. 3 and 4.
  • the six pairs of conductors are located in an aluminum tube 22.
  • a first heat insulation 23 of plastic foils with reflecting metal layers is places.
  • An intermediate aluminum shield 24 is placed over the insulation 23.
  • the shield 24 is in heat-conductive relation with aluminum tubings 25 which transport liquid nitrogen.
  • a second heat insulation 26 also comprised of plastic foils with reflecting metal layers is placed-over the shield 24 and tubings 25.
  • the entire configuration is located in a longitudinally divided reinforced concrete pipe 27 which absorbs the outside atmospheric pressure. After the tube 22 and the heat insulation as well as the intermediate shield are embedded, the tube 22 is supported with respect to the pressure pipe 27 by thin threads 30 and the lid 28 is applied. 1
  • the pressure pipe 27 is provided on its exterior with a covering 29 of plastic or metal which is welded, soldered or cemented along its length.
  • the space between pipes 22 and 27 is evacuated.
  • the coaxial conductor pairs 21 may be pulled into tube 22 before or after the latter has been secured in pipe 27.
  • the free space 31 in tube 22 and the inside spaces 7 of the inside conductors of the conductor pair 21 serve to receive the liquid cooling helium.
  • Interwoven wires or fibers of insulating material between the conductor pairs 21 ensure that the cooling helium penetrates into all interstices and that the occurring gas bubbles rise to the top.
  • the tubing 22 which encloses the cooling helium may be extruded or pulled without a seam or it may be placed around the conductor pairs in the form of a sheet and thereafter welded longitudinally.
  • the insulating helium is contained in the spaces 5 between the conductors of the coaxial conductor pairs 21.
  • FIG. 6 illustrates an alternating current system comprised of three parallel noneoaxial conductors 41.
  • Each conductor is made of a tube of highly pure lead.
  • the spacers 42 are the plastic sleeves illustrated in FIGS. 3 and 4. They carry extruded tubes 43 of a synthetic material, such as, a polyethylene mixture which remains elastic at low temperatures. The exterior of these tubes may be provided with a low conductive coating.
  • the insulating material occupies the space 44 between the tubes 43 and the conductors 41.
  • cooling helium lies outside ofthc tubes 43 and inside the conductors 4l.
  • the three conductors are held together by tapes 45 so that the current forces will not force them apart. Because of these forces, the spacer 42 must be made stronger than is the case in coaxial conductor pairs.
  • a star-shaped spacer 46 is provided so that the space between the three tubes 43 can be traversed by the cooling helium.
  • a plurality of such three-phase systems may be combined into a single highvoltage cable and be disposed in a common helium tube 47 made of aluminum.
  • a disadvantage of this noncoaxial design is that alternating forces which occur between the three conductors produce losses in the spacers 42, 46 and synthetic tubes all having an elasticity less than ideal. This embodiment is therefore primarily recommended for smaller current intensities in single conductors.
  • FIG. 7 shows a longitudinal section through the outer pressure conduit of a cable in which a pipe is mounted for carrying the cooling helium.
  • the helium tube 5 is illustrated with solid lines to show its position prior to cooling and with dashed lines to show its position after cooling.
  • the outer pressure tube is designated by reference numeral 52 and the bracing between the helium tube SI and the pressure tube 52 is designated by reference numeral 53.
  • the helium tube 51 assumes only a very slight snakelike configuration. However, the tube 51 is not completely straight to ensure that it will bend toward the correct side after being reheated.
  • the heat insulation is pressed at one side against the pressure tube 52. This is permissible for super insulation since the required distance between the individual foils is restored during the cooling process.
  • FIG. 8 illustrates a deice wherein superconducting alternating-current cables having a plurality of three-phase systems are utilized for limiting short circuits in a spatially expanded distribution network.
  • the distribution network 6] is fed by a distant power station 62.
  • Each feeder point 63 of the network 61 is connected via switches 64 to one subsystem 65 of the cable 66.
  • the heat insulation 68 is illustrated by dashed lines.
  • the short circuit power flows over the corresponding subsystem, the inductance of which, limits this flow. If the short circuit is simultaneously isolated by switch 64 and a corresponding switch 67 at the power plant end of the subsystem, and is also disconnected in the distribution network by means of meshnetwork switches, then the remaining network will stay in operation.
  • FIGS. 8 illustrates a so-called one-pole illustration wherein only one conductor is shown of the three conductors of the three-phase network 61 and the subcables 65.
  • the individual subcable can consist, for example, of the three-phase system shown in FIG. 6 or of three coaxial pairs of conductors, each, as illustrated in FIGS. 1 to 4.
  • the cable shown in FIGS. 5 contains two'such three-phase subcables.
  • Pressure means 69 connected to the spaces for insulting helium of the subcables 65 are disposed at the ends and along the length of the cable.
  • said insulating helium I being liquid and being at a pressure greater than that of said cooling liquid.
  • said insulating helium being gaseous and being at a pressure lower than that of said cooling helium.
  • a cable according to claim 1 comprising pressure means at each end of the cable for maintaining a difference in pressure between said insulating helium and said cooling helium.
  • a cable according to claim 1 comprising pressure means at predetermined locations along the length of said cable for maintaining a difference in pressure between said insulating helium and said cooling helium.
  • said first conductor means and said second conductor means together forming a coaxial conductor pair and an outer enclosure surrounding said coaxial conductor pair so as to define a space therebetween for conducting additional cooling helium in surrounding relation to said coaxial conductor pair.
  • said first conductor and said second conductor means both being annular members of metal, a layer of superconductive material being disposed on each of said annular members so as to be coaxial therewith 8.
  • said first conductor means comprising an annular member of insulating material
  • said second conductor means comprising a tubular member of insulating material surrounding said annular member so as to define a space therebetween for said insulating helium, a layer of superconductive material being disposed on said annular member so as to be coaxial therewith, and another layer of superconductive material being disposed on said tubular member so as to be coaxial therewith.
  • a cable according to claim 1 said first conductor means being at a potentialdifferent than that of said second conductor means, and a spacer of insulation material disposed inter mediate said first conductor means and said second conductor means for maintaining the former separate from the latter, said spacer having a volume substantially less than that of said space.
  • said spacer being a spiral spring consisting of a thread of synthetic material spirally wound about said conductor means.
  • said spacer being a plurality of conical sleeve members each consisting of synthetic material, each of said sleeve members having a slot and openings in its wall and being slidably mounted on said first conductor means.
  • a cable according to claim 9 a wrap of insulating material having a low dielectric loss factor being disposed between said spacer and said second conductor means.
  • a cable according to claim 1 said first conductor means and said second conductor means together constituting a conductor pair, said cable comprising a plurality of said conductor pairs, a pipe wherein said conductor pairs are disposed, said pipe containing additional cooling helium surroundings said conductor pairs, and a conduit, said pipe being disposed within said conduit so as to define an annular heat-insulating space therebetween.
  • a cable according to claim 13 comprising a foil of synthetic material having a layer of reflecting metal, said foil being disposed intermediate said pipe and said conduit.
  • a cable according to claim 14 comprising a plurality of said foils disposed intermediate said pipe and said conduit, and intermediate shield disposed between two adjacent ones of said foils, and a supply of liquid nitrogen in operative proximity to said shield for cooling the same.
  • conduit being longitudinally disposed in a snakelike configuration and having a height of curvature, at a given transverse section, less than that of said pipe at the same section.
  • a superconducting cable according to claim 18 for interconnecting a power station with feeder points of a dis'tribu tion network, having said number of conductor pairs connected to said feeder points at one end and to the power station at the other end.
  • said annular members consisting of metal selected from the group consisting of aluminum, copper and lead.
  • a cable according to claim 1 comprising solid insulation members disposed in said space at the ends ofthe cable.
  • a superconducting cable according to claim 23 for interconnecting a power station with feeder points of a distribution network, having said number of said three-phase systems connected to said feeder points at one end and to the power station at the other end.
  • a superconducting current cable comprising a tubular electrical conductor means a fluid of cooling helium inside said conductor means, a tubular member of synthetic material concentric with and enclosing said conductor means and defining a space therebetween, a fluid of insulating helium in said space, and an outer enclosure surrounding said tubular member of synthetic material and defining a second space .therebetween, and additional cooling helium in said second space, said conductor means consisting at least partially of a superconductive material.

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Cited By (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3715451A (en) * 1971-09-14 1973-02-06 A Hammer Superconductor structure, and method of making the same
US3715453A (en) * 1971-04-28 1973-02-06 Co Generale D Electricite Cryogenic connection enclosure
US3723634A (en) * 1971-03-04 1973-03-27 Gen Electricite And L Air Liqu Cryogenic cable and process for making the same
US3730966A (en) * 1971-01-21 1973-05-01 Gen Electric Cryogenic cable
US3735018A (en) * 1970-09-02 1973-05-22 Kabel Metallwerke Ghh Supercooled electric cable
US3736365A (en) * 1971-04-14 1973-05-29 Comp Generale Electricite Cryogenic cable
US3749811A (en) * 1971-03-10 1973-07-31 Siemens Ag Superconducting cable
US3780205A (en) * 1971-08-23 1973-12-18 M Aupoix Thermal insulation device for a very low-temperature line
US3904394A (en) * 1972-10-21 1975-09-09 Philips Corp Cold transport line
US3933037A (en) * 1973-02-06 1976-01-20 Centre National D'etudes Spatiales Device including a thermostatic enclosure, which is suspended from a tropospheric balloon
US3959549A (en) * 1973-08-08 1976-05-25 Siemens Aktiengesellschaft Multi-layer insulation for deep-cooled cables
US4394534A (en) * 1980-01-14 1983-07-19 Electric Power Research Institute, Inc. Cryogenic cable and method of making same
US4397807A (en) * 1980-01-14 1983-08-09 Electric Power Research Institute, Inc. Method of making cryogenic cable
US4409579A (en) * 1982-07-09 1983-10-11 Clem John R Superconducting magnetic shielding apparatus and method
FR2553578A1 (fr) * 1983-10-13 1985-04-19 Telefunken Electronic Gmbh Dispositif pour un composant electronique fonctionnant a basses temperatures
USH369H (en) 1982-03-15 1987-11-03 The United States Of America As Represented By The Department Of Energy Mechanically stable, high aspect ratio, multifilar, wound, ribbon-type conductor and method for manufacturing same
WO1999007003A1 (en) * 1997-08-01 1999-02-11 Eurus Technologies, Inc. A high temperature superconductor and method of making and using same
WO2001033579A1 (en) * 1999-10-29 2001-05-10 Nkt Cables A/S Method of producing a superconducting cable
US20020035039A1 (en) * 1998-12-24 2002-03-21 Marco Nassi Superconducting cable
US20030178080A1 (en) * 2002-03-13 2003-09-25 Nexans Pipeline for the transport of refrigerated media
US6697712B1 (en) * 2000-04-24 2004-02-24 Utilx Corporation Distributed cable feed system and method
US20060175078A1 (en) * 2003-09-24 2006-08-10 Sumitomo Electric Industries, Ltd. Super-conductive cable
US20060284711A1 (en) * 2005-05-26 2006-12-21 Siemens Magnet Technology Ltd. Electromagnet
US20090084581A1 (en) * 2007-09-28 2009-04-02 Vivant Medical, Inc. Cable Stand-Off
US20090247412A1 (en) * 2008-03-28 2009-10-01 American Superconductor Corporation Superconducting cable assembly and method of assembly
US20120025535A1 (en) * 2011-05-26 2012-02-02 Christof Martin Sihler Methods and systems for direct current power transmission
US20120094553A1 (en) * 2009-06-12 2012-04-19 Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd., Bus Bar and Connector
US20130233592A1 (en) * 2012-03-06 2013-09-12 Shenzhen Luxshare Precision Industry Co., Ltd. Signal transmission line disposed with conductive plastic material layer
US20130269966A1 (en) * 2010-12-15 2013-10-17 Robert Emme High Voltage Electric Cable
EP2693449A1 (en) 2012-07-31 2014-02-05 Nexans Electric conductor element
US20190066878A1 (en) * 2015-10-19 2019-02-28 Siemens Aktiengesellschaft Energy Transmission Apparatus For A Vehicle
US11264148B2 (en) * 2015-12-25 2022-03-01 Hitachi Metals, Ltd. Composite cable and composite harness
CN115954154A (zh) * 2023-03-15 2023-04-11 宇航电缆有限公司 一种复合式的便捷低压电缆

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2140195B (en) * 1982-12-03 1986-04-30 Electric Power Res Inst Cryogenic cable and method of making same

Cited By (49)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3735018A (en) * 1970-09-02 1973-05-22 Kabel Metallwerke Ghh Supercooled electric cable
US3730966A (en) * 1971-01-21 1973-05-01 Gen Electric Cryogenic cable
US3723634A (en) * 1971-03-04 1973-03-27 Gen Electricite And L Air Liqu Cryogenic cable and process for making the same
US3749811A (en) * 1971-03-10 1973-07-31 Siemens Ag Superconducting cable
US3736365A (en) * 1971-04-14 1973-05-29 Comp Generale Electricite Cryogenic cable
US3715453A (en) * 1971-04-28 1973-02-06 Co Generale D Electricite Cryogenic connection enclosure
US3780205A (en) * 1971-08-23 1973-12-18 M Aupoix Thermal insulation device for a very low-temperature line
US3715451A (en) * 1971-09-14 1973-02-06 A Hammer Superconductor structure, and method of making the same
US3904394A (en) * 1972-10-21 1975-09-09 Philips Corp Cold transport line
US3933037A (en) * 1973-02-06 1976-01-20 Centre National D'etudes Spatiales Device including a thermostatic enclosure, which is suspended from a tropospheric balloon
US3959549A (en) * 1973-08-08 1976-05-25 Siemens Aktiengesellschaft Multi-layer insulation for deep-cooled cables
US4394534A (en) * 1980-01-14 1983-07-19 Electric Power Research Institute, Inc. Cryogenic cable and method of making same
US4397807A (en) * 1980-01-14 1983-08-09 Electric Power Research Institute, Inc. Method of making cryogenic cable
USH369H (en) 1982-03-15 1987-11-03 The United States Of America As Represented By The Department Of Energy Mechanically stable, high aspect ratio, multifilar, wound, ribbon-type conductor and method for manufacturing same
US4409579A (en) * 1982-07-09 1983-10-11 Clem John R Superconducting magnetic shielding apparatus and method
FR2553578A1 (fr) * 1983-10-13 1985-04-19 Telefunken Electronic Gmbh Dispositif pour un composant electronique fonctionnant a basses temperatures
DE3337195A1 (de) * 1983-10-13 1985-04-25 Telefunken electronic GmbH, 7100 Heilbronn Anordnung fuer ein bei niederen temperaturen betriebsfaehiges elektronisches bauelement
US4625229A (en) * 1983-10-13 1986-11-25 Telefunken Electronic Gmbh Arrangement for permitting rapid cooling of an electronic component operable at low temperatures
WO1999007003A1 (en) * 1997-08-01 1999-02-11 Eurus Technologies, Inc. A high temperature superconductor and method of making and using same
US6844490B2 (en) * 1998-12-24 2005-01-18 Pirelli Cavi E Sistemi S.P.A. Superconducting cable
US20020035039A1 (en) * 1998-12-24 2002-03-21 Marco Nassi Superconducting cable
WO2001033579A1 (en) * 1999-10-29 2001-05-10 Nkt Cables A/S Method of producing a superconducting cable
US6697712B1 (en) * 2000-04-24 2004-02-24 Utilx Corporation Distributed cable feed system and method
US20030178080A1 (en) * 2002-03-13 2003-09-25 Nexans Pipeline for the transport of refrigerated media
US6732765B2 (en) * 2002-03-13 2004-05-11 Nexans Pipeline for the transport of refrigerated media
US20060175078A1 (en) * 2003-09-24 2006-08-10 Sumitomo Electric Industries, Ltd. Super-conductive cable
US7598458B2 (en) 2003-09-24 2009-10-06 Sumitomo Electric Industries, Ltd. Super-conductive cable
EP1667171A4 (en) * 2003-09-24 2008-07-23 Sumitomo Electric Industries SUPERCONDUCTING CABLE
US20060284711A1 (en) * 2005-05-26 2006-12-21 Siemens Magnet Technology Ltd. Electromagnet
US20090039991A1 (en) * 2005-05-26 2009-02-12 Siemens Magnet Technology Ltd. Electromagnet
US7859375B2 (en) * 2005-05-26 2010-12-28 Siemens Plc Electromagnet
US20090084581A1 (en) * 2007-09-28 2009-04-02 Vivant Medical, Inc. Cable Stand-Off
US8651146B2 (en) * 2007-09-28 2014-02-18 Covidien Lp Cable stand-off
US20090247412A1 (en) * 2008-03-28 2009-10-01 American Superconductor Corporation Superconducting cable assembly and method of assembly
WO2009120833A1 (en) * 2008-03-28 2009-10-01 American Superconductor Corporation Superconducting cable assembly and method of assembly
US8478374B2 (en) 2008-03-28 2013-07-02 American Superconductor Corporation Superconducting cable assembly and method of assembly
US20120094553A1 (en) * 2009-06-12 2012-04-19 Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd., Bus Bar and Connector
US8500473B2 (en) * 2009-06-12 2013-08-06 Kobe Steel, Ltd. Bus bar and connector
US8847069B2 (en) * 2010-12-15 2014-09-30 Abb Technology Ag High voltage electric cable
US20130269966A1 (en) * 2010-12-15 2013-10-17 Robert Emme High Voltage Electric Cable
US20120025535A1 (en) * 2011-05-26 2012-02-02 Christof Martin Sihler Methods and systems for direct current power transmission
US8373307B2 (en) * 2011-05-26 2013-02-12 General Electric Company Methods and systems for direct current power transmission
US20130233592A1 (en) * 2012-03-06 2013-09-12 Shenzhen Luxshare Precision Industry Co., Ltd. Signal transmission line disposed with conductive plastic material layer
US8735725B2 (en) * 2012-03-06 2014-05-27 Shenzhen Luxshare Precision Industry Co., Ltd. Signal transmission line disposed with conductive plastic material layer
EP2693449A1 (en) 2012-07-31 2014-02-05 Nexans Electric conductor element
US20190066878A1 (en) * 2015-10-19 2019-02-28 Siemens Aktiengesellschaft Energy Transmission Apparatus For A Vehicle
US11264148B2 (en) * 2015-12-25 2022-03-01 Hitachi Metals, Ltd. Composite cable and composite harness
CN115954154A (zh) * 2023-03-15 2023-04-11 宇航电缆有限公司 一种复合式的便捷低压电缆
CN115954154B (zh) * 2023-03-15 2023-05-05 宇航电缆有限公司 一种复合式的便捷低压电缆

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DE1640750B1 (de) 1971-04-22
FR1600958A (enrdf_load_html_response) 1970-08-03
SE342343B (enrdf_load_html_response) 1972-01-31
GB1245655A (en) 1971-09-08

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