Patent Description:
High-field magnets are often constructed from superconductors due to the capability of superconductors to carry a high current without resistance. Such magnets may, for instance, carry currents greater than <NUM> kA. <CIT> discloses a superconductor cable having a plurality of flat, tape-shaped ribbon superconductor wires assembled to form a stack having a rectangular cross section, the stack having a twist about a longitudinal axis of the stack. Multiple superconductor cables including twisted stacked-cables of the flat-tape-shaped superconductor wires, and power cable comprising the twisted flat-tape stacked cables are disclosed. Superconducting power cable disposed within and separated from an electrical insulator with a space passing cryo-coolant between the superconducting cable and insulator is also disclosed. <CIT> discloses high-current, compact, flexible conductors containing high temperature superconducting (HTS) tapes. The HTS tapes are arranged into a stack, a plurality of stacks are arranged to form a superstructure, and the superstructure is twisted about the cable axis to obtain a HTS cable. There remains a need for reducing eddy current and/or current coupling heating in a superconducting cable.

According to the present invention, there is provided a cable according to claim <NUM> comprising a plurality of high temperature superconductor (HTS) components, a plurality of electrically conductive segments extending along the cable, each of the plurality of electrically conductive segments comprising a groove in which one of the plurality of HTS components is arranged, and an electrically insulating material arranged between adjacent electrically conductive segments of the plurality of electrically conductive segments that electrically insulates the plurality of electrically conductive segments from one another.

According to some aspects, a magnet is provided comprising a coil comprising a plurality of windings of a cable according to the invention.

The foregoing apparatus and method embodiments may be implemented with any suitable combination of aspects, features, and acts described above or in further detail below, within the scope defined by the appended claims. These and other aspects, embodiments, and features of the present teachings can be more fully understood from the following description in conjunction with the accompanying drawings.

Operating high-field magnets at high current (e.g., greater than <NUM> kA) may present challenges when operating in variable current mode, usually referred to as an alternating current (AC) mode. In particular, inductive heating may occur as a result of the changing magnetic field. In cases where the magnet comprises a current-carrying superconductor, such inductive heating may cause at least part of the superconductor to become non-superconducting ("normal") leading to temperature instability and possible damage to the magnet. Sources of inductive heating may include eddy currents induced within a conductor, and/or coupling currents generated within two parallel current paths that are close to one another.

A high-field superconducting magnet often comprises multiple electrically insulated cable turns grouped in a multi-layer or multi-pancake arrangement. This allows the magnet to be driven in an AC mode by changing the power supply current over time, which in turn causes the field produced by the magnet to changes over time as well. During a transient event, such as charging the magnet or discharging the magnet, each cable turn of the magnet is exposed to a variable magnetic field. As noted above, this variation in field can induce eddy currents (and therefore heating) in the electrically conducting parts of the cable. Such heating can significantly reduce the superconductor temperature margin (i.e. the difference between a temperature at which the magnet is operating and the temperature above which the superconductor may lose its superconducting characteristics). Thus, if uncontrolled, such heating can lead to the superconductor losing its superconducting abilities, often referred to as a "quench.

Conventional approaches to reduce the AC losses in a superconducting cable include reducing the size of the current-carrying wires and/or twisting the wires into a spiral. The smaller wires may reduce the size of the hysteresis losses and coupling currents that develop between parallel current paths, whereas twisting may reduce the length over which two conductive paths are parallel to one another. For instance, the so-called Cable in Conduit Conductor (CICC) braided cable approach includes small diameter filaments embedded and twisted together with conductive wires.

These approaches are very difficult or impossible to implement with respect to high temperature superconductors (HTS), however, which are typically not formed from wires. Rather, an HTS cable typically comprises a superconductor component having a wide aspect ratio, which is often referred to as a "tape. " It can be challenging to reduce the size of such a tape into smaller units and also to twist the highly aspected tape, however. As such, conventional approaches to reduce AC losses in a superconducting cable may be ineffective for HTS cables.

The inventors have recognized and appreciated concepts, structures, processes and techniques for reducing eddy current and/or current coupling heating in a superconducting cable by arranging resistive layers within the structural components of the cable. In particular, the structure that supports the current-carrying components may be partitioned and at least partially insulated between the partitions. Introduction of such resistive layers has been observed to reduce eddy currents and coupling heating by a significant factor, as discussed further below.

In at least some implementations, the current-carrying components such as HTS tape may be otherwise configured as in conventional approaches. For instance, a cable may comprise an electrically conducting structure that supports one or more HTS tapes. The electrically conducting structure, sometimes referred to as a "former," may be partitioned so that separate segments of the former each support one or more HTS tapes and so that the separate segments are separated from one another by electrically insulating material. In cases where a plurality of HTS tapes are supported by one segment of the former, the HTS tapes may be arranged in a stack, layered on top of each other along a direction that is the same as the smallest dimensional axis of the tape (e.g., tapes that are long, wide and have a small thickness are layered in the thickness direction).

According to some embodiments, a superconducting cable may include a number of segments comprising at least one HTS. In some cases, the segments are radial segments comprising at least one HTS. In some cases, the radial segments may exhibit radial symmetry. Each segment may comprise a separate and independent current-carrier that includes, or is composed of, an HTS, and an electrical insulator may be arranged between the radial segments. As a result, the cable may comprise multiple current-carrying regions separated by insulators.

According to some embodiments, a superconducting cable may comprise a central cooling channel. This channel may pass through an interior of the cable and be adjacent to the multiple partitions of the structure that supports the current-carrying components, thereby providing cooling to the multiple partitions and to the HTS components supported by the multiple partitions. In some cases, the channel may be formed by omitting regions of the partitions of the cable to form an interior hollow space. Additionally, or alternatively, the channel may be formed by a tubular element that passes through the interior of the cable and provides support to the cooling channel. Such a tubular element may comprise the same, or different, material(s) than the partitions of the structure that support the current-carrying components.

According to some embodiments, a superconducting cable may comprise a number of partitions of the structure that supports the current-carrying components that are twisted about a common axis. Each partition of the structure may, for instance, follow a helical path while supporting a respective one of the current-carrying components.

Following below are more detailed descriptions of various concepts related to, and embodiments of, techniques for reducing eddy current and/or current coupling heating in a superconducting cable. It should be appreciated that various aspects described herein may be implemented within the scope defined by the appended claims.

<FIG> illustrates a cross-sectional view of a superconducting cable, according to some embodiments. In the example of <FIG>, cable <NUM> comprises a plurality of electrically conductive segments, here three electrically conductive segments <NUM>, which are separated from one another by an electrically insulating material <NUM>. Each of the electrically conductive segments 110a, 110b, 110c generally referred to herein as <NUM> supports, and is in electrical contact with, a respective superconductor component 130a, 130b, 130c generally referred to herein as <NUM>. As discussed above, electrically insulating material <NUM> may reduce eddy currents and coupling heating (and in some cases by a significant factor) compared with a cable that utilizes a single region of electrically conductive material to support each of the superconductor components of the cable. The insulating material <NUM> fully insulates each of the electrically conductive segments <NUM> from one another.

During operation of the cable <NUM>, at least the superconductor components <NUM> are cooled to below their superconducting transition so that they may carry current at zero resistance. The electrically conductive segments <NUM> act as stabilizers during a quench: when one of the superconductor components <NUM> quenches, heat may be conducted through the electrically conductive segment that supports the quenched superconductor component to the other electrically conductive segments, thereby quenching the whole cross section of the cable. Subsequently, a non-superconducting zone within superconductor components <NUM> may be created and propagate along the cable.

According to some embodiments, each electrically conductive segment <NUM> may be arranged in electrical contact with a respective superconductor component <NUM>. Such contact may occur as a result of direct physical contact between the electrically conductive segment and the respective superconductor component, and/or may occur as a result of indirect contact via an intermediate electrically conductive material.

In the example of <FIG>, the electrically conductive segments <NUM> are arranged in a radially symmetric manner around a central axis of the cable. This configuration may provide for simpler fabrication of the cable, since the electrically conductive segments may be fabricated with the same cross-sectional dimensions, then assembled in the cable <NUM>. Notwithstanding these advantages, the techniques described herein are not limited to electrically conductive segments exhibiting such symmetry, as any suitable size and shape of electrically conductive segments may be employed in a cable.

According to some embodiments, electrically conductive segments <NUM> may comprise, or may consist of, copper. Copper may represent a desirable material due to its high thermal conductivity, thereby providing a stabilizing function in case of a quench, as well as being electrically conductive. Other suitable materials that electrically conductive segments <NUM> may comprise, or may consist of, include aluminum.

According to some embodiments, electrically insulating material <NUM> is arranged to contact different ones of the electrically conductive segments <NUM> on either side. As shown in <FIG>, electrically insulating material <NUM> is arranged between adjacent pairs of the electrically conductive segments <NUM>, and may be arranged so as to contact both segments of the pair (ideally, so as to leave no gaps, or substantially no gaps, between the electrically insulating material <NUM> and each electrically conductive segment). In some embodiments, the insulating material <NUM> may be provided in the form of a tape that may be arranged between the pairs of the electrically conductive segments <NUM>. In some cases, the tape may be an adhesive tape and adhered to the adjacent electrically conductive segments <NUM> via the adhesive so that the tape is adhered to the electrically conductive segments.

According to some embodiments, superconductor components <NUM> may comprise one or more high temperature superconductors (HTS). As used herein, a "high temperature superconductor" or "HTS" refers to a material that has a critical temperature above <NUM>°K, wherein the critical temperature refers to the temperature below which the electrical resistivity of the material is zero. The critical temperature can in some cases depend on other factors such as the presence of an electromagnetic field. It will be appreciated that where the critical temperature of a material is referred to herein, this may refer to whatever the critical temperature happens to be for that material under the given conditions.

In some embodiments, superconductor components <NUM> may comprise an HTS tape, which is a long, thin strand of HTS material with cross-sectional dimensions in the range of about <NUM> to about <NUM> in thickness (or height) and a width in the range of about <NUM> to about <NUM> (and with a length that extends along the length of the cable, i.e., into and out of the page in the example of <FIG>). In some embodiments, HTS tape may comprise a polycrystalline HTS and/or may have a high level of grain alignment. In some embodiments, superconductor components <NUM> may comprise a stack of HTS tapes, being a plurality of HTS tapes arranged on top of one another along the width and length directions. An HTS tape stack may thereby have a thickness equal to (or approximately equal to) the thickness of an individual tape multiplied by the number of tapes in the stack.

According to some embodiments, insulating material <NUM> may comprise polyimide (e.g., Kapton®), epoxy resin, phenolic resin, a plastic, an elastomer, steel (e.g., stainless steel) or combinations thereof. According to some embodiments, insulating material may have a breakdown voltage or dielectric strength of greater than <NUM> kV/mm, of greater than <NUM> kV/mm, of greater than <NUM> kV/mm, of greater than <NUM> kV/mm.

In some embodiments, insulating material <NUM> may comprise, or may consist of, a high-resistivity material that is nonetheless electrically conductive to some extent. In this respect, references to material <NUM> being "insulating" refers to the fact that the material <NUM> is much less electrically conductive than the material making up the electrically conductive segments <NUM>. For instance, in some embodiments, the electrically conductive segments <NUM> may comprise a highly conductive material such as copper, whereas the insulating material <NUM> may comprise steel, which is not strictly an insulator but is nonetheless far more insulating than copper.

In the example of <FIG>, the electrically conductive segments <NUM> may provide mechanical integrity to the cable in addition to the aforementioned advantages with respect to quenching behavior. The electrically conductive segments <NUM> may be formed into or may conform to a desired shape and may provide a substantial amount of structural strength to the cable. This is in contrast to other superconducting cables such as the Cable in Conduit Conductor (CICC) braided cables discussed above, which feature twisted copper rods that can deform under high electromagnetic loads.

According to some embodiments, electrically conductive segments <NUM> may be twisted along the length of the cable <NUM>. That is, the electrically conductive segments <NUM> may be twisted around a central longitudinal axis of the cable; as such, the cross-sectional view of <FIG> may be accurate at various points along the cable but for the rotational orientation of the view shown, which will rotate about the center of the cable as the cross-sectional view is moved along the length of the cable. A helical path is one example of a twisted path that the electrically conductive segments may follow around the central longitudinal axis of the cable. In such a configuration, the electrically conductive segments <NUM> may be aligned along respective helical paths with a center of each helix being the central longitudinal axis of the cable. Similarly, the superconductor components <NUM> may be supported by the electrically conductive segments <NUM> along the length of the cable in the manner shown in <FIG>, and thereby also be aligned along respective helical paths with a center of each helix being the central longitudinal axis of the cable. Arranging the superconductor components <NUM> along twisted paths may reduce the length over which two conductive paths are parallel to one another, and thereby reduce this source of inductive heating.

According to some embodiments, cable <NUM> may comprise one or more cooling channels, such as tubular cooling channels that may run along the longitudinal axis of the cable. Although the example of <FIG> does not illustrate any cooling channels, in general any number of channels may be formed or otherwise provided through the cable to provide cooling to the electrically conductive segments <NUM> and/or to the superconductor components <NUM>. Such channels may for instance provide a path for cryogenic liquid such as liquid helium or liquid nitrogen to flow and carry heat away from the electrically conductive segments <NUM> and/or the superconductor components <NUM>. In some cases, one or more cooling channels may be arranged in contact with, or in close proximity to, the electrically conductive segments <NUM>. In such cases, cooling of the superconductor components <NUM> may be achieved indirectly through cooling of the electrically conductive segments. In other cases, one or more cooling channels may be arranged in contact with, or in close proximity to, the superconductor components <NUM>. Coolant may be provided through a cooling channel at a high pressure, such as above <NUM> bar.

Although not explicitly shown in <FIG>, according to some embodiments, cable <NUM> may comprise a jacket arranged exterior to the electrically conductive segments <NUM>. A jacket may provide additional structural stability over and above that provided by the electrically conductive segments <NUM>, and may for instance comprise, or may consist of, steel, Inconel®, Nitronic® <NUM>, Nitronic® <NUM>, Incoloy®, or combinations thereof.

<FIG> illustrates a cross-sectional view of a superconducting cable, according to some embodiments. Cable <NUM> is an example of cable <NUM> shown in <FIG> that includes electrically conductive segments <NUM> arranged in a radially symmetric manner around a central cooling channel <NUM>. The electrically conductive segments <NUM> are configured to hold respective HTS tape stacks <NUM> within respective channels <NUM> (<FIG>) within each segment. In the example embodiment of <FIG>, the channels <NUM> are arranged at a perimeter of each segment. <FIG> illustrates a single electrically conductive segment <NUM> separately from cable <NUM> to depict the channel <NUM>. It may be noted that cable <NUM> may be produced from three instances of the same electrically conductive segment <NUM> arranged as shown in <FIG>. The illustrative cable of <FIG> comprises a jacket <NUM> arranged exterior to the electrically conductive segments. According to some embodiments, jacket <NUM> may comprise, or may consist of, steel, Inconel®, Nitronic® <NUM>, Nitronic® <NUM>, Incoloy®, or combinations thereof.

In the example of <FIG>, the HTS tape stacks <NUM> are arranged in contact with an alloy <NUM>, which provides at least part of the electrical contact between the HTS tape stacks and each respective electrically conductive segment <NUM>. As discussed further below, one technique to produce electrical contact between the HTS tape and the electrically conductive segment is to fill space between the tape and the segment with a liquid alloy such as solder. As such, the alloy <NUM> may comprise, or may consist of, a Pb and/or Sn solder. In some embodiments, the alloy <NUM> may comprise a metal having a melting point of less than <NUM>, wherein at least <NUM> wt% of the metal is Pb and/or Sn, and at least <NUM> wt% of the metal is Cu.

<FIG> illustrates a cross-sectional view of a superconducting cable, according to some embodiments. Cable <NUM> is an example of cable <NUM> shown in <FIG> that includes electrically conductive segments <NUM> arranged in a radially symmetric manner around a perimeter of a central cooling channel <NUM>. The electrically conductive segments <NUM> are configured to hold respective HTS tape stacks <NUM> within respective channels arranged within each segment. In the example embodiment of <FIG>, the channels <NUM> are arranged at a perimeter of each segment. <FIG> illustrates a single electrically conductive segment <NUM> separately from cable <NUM> to depict the channel <NUM>. It may be noted that cable <NUM> may be produced from five instances of the same electrically conductive segment <NUM> arranged as shown in <FIG>. According to some embodiments, jacket <NUM> may comprise, or may consist of, steel, steel, Inconel®, Nitronic® <NUM>, Nitronic® <NUM>, Incoloy®, or combinations thereof.

In the example of <FIG>, the HTS tape stacks <NUM> are arranged in contact with an alloy <NUM>, which provides at least part of the electrical contact between the HTS tape stacks and each respective electrically conductive segment <NUM>. As discussed further below, one technique to produce electrical contact between the HTS tape and the electrically conductive segment is to fill space between the tape and the segment with a liquid alloy such as solder. As such, the alloy <NUM> may comprise, or may consist of, a Pb and/or Sn solder. In some embodiments, the alloy <NUM> may comprise a metal having a melting point that is at least <NUM> and less than <NUM>, wherein at least <NUM> wt% of the metal is Pb and/or Sn, and at least <NUM> wt% of the metal is Cu.

In the examples of <FIG> the channels of the electrically conductive segments in each cable that house the HTS tape stacks are depicted as being rectangular in cross-section, though it will be appreciated that the channels are not limited to this shape. For example, the channels of the electrically conductive segments comprise a groove into which a superconductor is inserted so that the channels have a curved inner surface.

<FIG> depicts eddy currents within a superconducting cable having a single conductive structure supporting multiple HTS tape stacks, according to some embodiments. As may be noted from the illustrative example of <FIG>, eddy currents represented by arrows may circulate around the cross section of the cable <NUM> and through the HTS tape stacks <NUM>. As shown in the example of <FIG>, the cable includes a single conductive structure <NUM> that supports all four of the HTS stacks <NUM>.

In contrast, <FIG> depicts eddy currents within a superconducting cable comprising four electrically conductive segments <NUM> each supporting a separate HTS tape stack <NUM> and comprising insulating material between the segments, according to some embodiments. As may be noted from the illustrative example of <FIG>, eddy currents represented by arrows circulate within cable <NUM> in much smaller paths within each separate electrically conductive segment <NUM> when compared with the paths shown in <FIG>. As a result of the smaller current loops in cable <NUM>, inductive heating in the cable is expected to be much lower than in cable <NUM> when both cables operate in an AC mode.

<FIG> further illustrate the performance differences between a superconducting cable that has a single conductive structure supporting multiple HTS tapes and a superconducting cable comprising multiple electrically conductive segments and insulating material between the segments, according to some embodiments. <FIG> depict results of finite element modeling of cables of these types when each is subjected to a current sweep of the transverse external magnetic field, as shown in <FIG>. Specifically, as shown in <FIG>, a <NUM> second +<NUM> kA/-<NUM> kA transport current sweep was simulated in a +<NUM> T / -<NUM> T sweep of the transverse external magnetic field.

As shown in <FIG>, which depicts a qualitative amount of power deposited in the cable by eddy currents over time, the sweep produces a much greater amount of power in the conventional cable (light gray) than in the cable comprising multiple electrically conductive segments (black). Similarly, as shown in <FIG>, which depicts a qualitative energy deposited in the cable by eddy currents over time, the sweep deposits a much greater amount of energy in the conventional cable (light gray) than in the cable comprising multiple electrically conductive segments (black).

<FIG> is an isometric view of a superconducting cable having portions of an outer jacket <NUM> removed to reveal multiple electrically conductive segments in a twisted configuration. As discussed above in relation to <FIG>, in some embodiments the multiple electrically conductive segments may be twisted around a common axis along the length of the cable (e.g. a common central longitudinal axis of the cable). This configuration is shown in <FIG>, which depicts cable <NUM> comprising superconductor components <NUM> and insulating portions <NUM>; the intervening electrically conductive segments which fill the space between the superconductor components and the insulating portions are not shown for clarity. As discussed above, arranging the superconductor components in a twisted shape may reduce the length over which two conductive paths are parallel to one another, and thereby reduce this source of inductive heating. Combined with the reduction in the size of eddy current loops afforded by the insulated electrically conductive segments as discussed above, inductive heating may be dramatically reduced.

<FIG> depict cross-sectional views of a superconducting cable with various external insulation arrangements, according to some embodiments. For purposes of illustration, a cable similar to that shown in <FIG> is depicted in <FIG> with the various external insulation arrangements. In the example of <FIG>, cable assembly <NUM> comprises a cable surrounded by a jacket <NUM> (e.g., a stainless steel jacket), which is wrapped in a first dielectric layer (e.g., a layer of polyimide such as Kapton®, a fiberglass cloth) <NUM>, around which is provided a second dielectric layer (e.g., fiberglass) <NUM>.

In the example of <FIG>, cable assembly <NUM> comprises a first dielectric layer (e.g., a polyimide layer, fiberglass cloth) <NUM> arranged around a cable, around which a jacket <NUM> is arranged. A second dielectric layer (e.g., a layer of fiberglass) <NUM> surrounds the jacket <NUM> (e.g., a stainless steel jacket).

In the example of <FIG>, cable assembly <NUM> comprises a dielectric layer (e.g., a polyimide layer, fiberglass cloth) <NUM> arranged around a cable, and a jacket <NUM> (e.g., a stainless steel jacket) arranged around the cable and dielectric <NUM>.

In some embodiments, a cable assembly may be wrapped in a dielectric (e.g., fiberglass cloth, polyimide) and then vacuum pressure impregnated to fill the remaining space between the cable turns with a dielectric, such as an epoxy resin. For instance, the cable assembly may be wrapped in a first dielectric, arranged in a number of turns, then vacuum pressure impregnated with epoxy. The epoxy may be cured via thermal means or otherwise.

In some embodiments, a cable assembly may be arranged within a structural matrix. For instance, the jacket may comprise a number of channels in which windings of a cable assembly (or windings of multiple cable assemblies) may be arranged. As such, the jacket may act as a structural support (e.g., structural plate) supporting multiple windings of one or more cable assemblies. Such a jacket may be surrounded by one or more dielectric layers as described above, in some embodiments.

<FIG> is a flowchart of a method of fabricating a superconducting cable, according to some embodiments. Method <NUM> begins in act <NUM> in which a plurality of electrically conductive segments are fabricated. Such fabrication may be accomplished through any subtractive or additive process including, but not limited to extrusion, machining and/or additive fabrication. For instance, structures may be fabricated (e.g., from a metal such as copper) having the cross-section shown in <FIG> or <FIG> (or any other cross-section suitable for subsequent insertion of a superconductor component and arrangement into a cable). In act <NUM>, the segments are also insulated with a suitable insulation material such as polyimide and/or any other dielectric. In some embodiments, the insulation material may be a tape, which may comprise an adhesive on either or both sides via which the insulation material may be adhered to the electrically conductive segments.

In act <NUM>, the electrically conductive segments fabricated in act <NUM> are assembled into a single structure. Optionally in act <NUM>, a cooling channel may be assembled, formed or otherwise provided via the electrically conductive segments. For example for the cable shown in <FIG>, a central cooling channel may be arranged with insulation around it in the center with the multiple electrically conductive segments surrounding it.

In act <NUM>, the assembled collection of electrically conductive segments (and optional cooling channel) may be twisted to produce a shape like that shown in <FIG>. For example, the assembly may be twisted along its length by holding the ends of the assembly in place and rotating them with respect to one another.

In act <NUM>, HTS tape stacks may be inserted into channels or other cavities within the assembled electrically conductive segments. In some cases, the HTS tape stacks may be fed into such channels or cavities, as sufficient space may be provided in the channels or cavities present in the electrically conductive segments to allow the HTS tape stacks to be safely pushed through the cable assembly. In act <NUM>, the assembly is inserted into a jack provided for structural stability (e.g., a stainless steel jacket) and the resulting cable wound into a desired shape.

In act <NUM>, any empty space present within channels or cavities of the cable (except for the cooling channel) may be filled by impregnating the space with a suitable alloy. In some embodiments, a vacuum pressure impregnation (VPI) process may be performed to fill the space with a Pb and/or Sn solder. Such a process may comprise one or more of the following steps: cleaning the empty space within the cable using an acidic solution following by a water rinse; evacuating the space within the cable; purging the space with an inert gas; depositing flux into the space to coat the HTS tape and the electrically conductive segments; draining any excess flux from the cable; heating the cable to a temperature below, at or above a temperature at which the alloy to be deposited will melt; and flowing a molten alloy (e.g., a PbSn solder) into the cable. In some embodiments, the HTS tape may be pre-tinned with a metal (e.g., a PbSn solder) to promote a good bond between the HTS tape and the alloy.

<FIG> is a three-dimensional graphic of a fusion power plant with a cutaway portion illustrating various components of the power plant, according to some embodiments. A magnet within a fusion power plant may be formed from a superconducting cable as described above. <FIG> shows a cross-section through a power plant and includes a magnet coil <NUM>, which is fabricated from, or otherwise includes, a superconducting cable as discussed and described above, a neutron shield <NUM>, and a core region <NUM>. According to some embodiments, the magnet coil <NUM> may be, or may form part of, a central solenoid and/or other poloidal field solenoidal coils.

Persons having ordinary skill in the art may appreciate other embodiments of the concepts, structures, processes, results, and techniques disclosed herein. It is appreciated that superconducting cables configured according to the concepts, structures, processes and techniques described herein may be useful for a wide variety of applications, including applications in which the superconducting cable is wound into a coil to form a magnet. For instance, one such application is conducting nuclear magnetic resonance (NMR) research into, for example, solid state physics, physiology, or proteins, for which such cables may be wound into a magnet. Another application is performing clinical magnetic resonance imaging (MRI) for medical scanning of an organism or a portion thereof, for which compact, high-field magnets are needed. Yet another application is high-field MRI, for which large bore solenoids are required. Still another application is for performing magnetic research in physics, chemistry, and materials science. Further applications is in magnets for particle accelerators for materials processing or interrogation; electrical power generators; medical accelerators for proton therapy, radiation therapy, and radiation generation generally; superconducting energy storage; magnetohydrodynamic (MHD) electrical generators; and material separation, such as mining, semiconductor fabrication, and recycling. It is appreciated that the above list of applications is not exhaustive, and there are further applications to which the concepts, structures, processes, and techniques disclosed herein may be put without deviating from their scope.

Having thus described several aspects of at least one embodiment of the disclosed concepts, structures, processes, and techniques, it is to be appreciated that various alterations, modifications, and improvements will readily occur to those skilled in the art, within the scope defined by the appended claims.

Also, the described concepts, structures, processes, and techniques may be embodied as a method, of which an example has been provided. The acts performed as part of the method may be ordered in any suitable way. Accordingly, embodiments may be constructed in which acts are performed in an order different than illustrated, which may include performing some acts simultaneously, even though shown as sequential acts in illustrative embodiments.

The terms "approximately" and "about" may be used to mean within ±<NUM>% of a target value in some embodiments, within ± <NUM>% of a target value in some embodiments, within ±<NUM>% of a target value in some embodiments, and yet within ±<NUM>% of a target value in some embodiments. The terms "approximately" and "about" may include the target value. The term "substantially equal" may be used to refer to values that are within ±<NUM>% of one another in some embodiments, within ±<NUM>% of one another in some embodiments, within ±<NUM>% of one another in some embodiments, and yet within ±<NUM>% of one another in some embodiments.

The term "substantially" may be used to refer to values that are within ±<NUM>% of a comparative measure in some embodiments, within ± <NUM>% in some embodiments, within ±<NUM>% in some embodiments, and yet within ±<NUM>% in some embodiments. For example, a first direction that is "substantially" perpendicular to a second direction may refer to a first direction that is within ±<NUM>% of making a <NUM>° angle with the second direction in some embodiments, within ± <NUM>% of making a <NUM>° angle with the second direction in some embodiments, within ±<NUM>% of making a <NUM>° angle with the second direction in some embodiments, and yet within ±<NUM>% of making a <NUM>° angle with the second direction in some embodiments.

Claim 1:
A cable (<NUM>) comprising:
a plurality of high temperature superconductor (HTS) components (130A, 130B, 130C);
a plurality of electrically conductive segments extending along the cable (110A, 110B, 110C), each of the plurality of electrically conductive segments comprising a groove in which one of the plurality of HTS components is arranged; characterised by
an electrically insulating material (<NUM>) arranged between adjacent electrically conductive segments of the plurality of electrically conductive segments that electrically insulates the plurality of electrically conductive segments from one another.