Device, Magnet, and Manufacturing Method

Abstract

Described herein are means for constructing robust high magnetic field superconducting magnets using simple fabrication techniques, and concepts, systems, and techniques that enable modular components that scale well towards commercialization. Utilizing non-insulated high temperature superconducting tape (HTS) enables an optimized coolant path - the resulting magnet assembly is inherently structurally strong, which enables maximum utilization of the high magnetic fields available by HTS technology. Additionally, the concepts described herein enable control of the quench induced current distribution in the tape stack and the surrounding upper structure in order to safely dissipate the quench energy while at the same time obtaining an acceptable magnet charge time. The end result is a structurally and thermally robust high magnetic field magnet assembly that is passively protected against quench failure situations.

Description

Background Art

[0001]

[0001] As is known in the art, existing techniques for fabricating high-field superconducting magnetics include (1) low-temperature superconductor (LTS) cable-in-conduit conductor (CICC) designs such as those used for ITER's toroidal field magnetics, and (2) high-temperature superconductor (HTS) designs based on HTS tapes wound directly into layer-wound coils or spiral-wound "pancake" coil assemblies. A method similar to CICC based on HTS conductors is further sought.

[0002]

[0002] In the CICC method, the conduit is electrically insulated from the winding pack. The coolant is constrained to flow inside the conduit. The shapes of the winding pack and the outer support shell define the shapes of the current path and the coolant path. For an example of an ITER toroidal field coil, the winding pack and the outer support shell are provided to have a D shape. The winding pack and the outer shell structure are mainly responsible for containing the Lorentz force generated by the high-field magnet (i.e., the winding pack and the shell must support the Lorentz load). In the case of a magnet quench event (which must be detected with high reliability and with sufficient lead time to reduce damage by an external protection system), the stored magnetic energy is dissipated into an external resistor at the magnet terminals. Thus, the current in the CICC avoids the normal regions in the superconductor and instead flows into the copper stabilizer.

[0003]

[0003] The need for copper stabilizers and coolant channels within the conduit, combined with the need for high voltage electrical insulation, complicates magnet design because these elements are structurally weak and yet they occupy a significant amount of volume within the winding. Additionally, the manufacturing process for CICC-based magnetic devices necessarily includes many steps, including stranding of the strands / tape, covering these sub-elements together, and bending and inserting the CICC into the winding, which is long and laborious.

Summary of the Invention

Means for Solving the Problems

[0004]

[0004] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key or essential features or combinations of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0005]

[0005] Described herein are means for constructing robust high magnetic field superconducting magnets using fabrication techniques that are relatively simple compared to conventional fabrication techniques, and concepts, systems, structures, and techniques that enable modular components that scale well towards commercialization. Utilizing non-insulated high temperature superconducting tape (HTS) enables enhanced (and ideally, optimized) coolant paths - the resulting magnet assembly is inherently structurally strong. This allows for a high degree (and ideally, maximum utilization) of the high magnetic fields available with HTS tape technology. Additionally, the concepts described herein safely dissipate quench energy while simultaneously obtaining an acceptable magnet charge time Enable control of the quench-induced current distribution in the tape stack and the surrounding upper structure. The end result is a structurally and thermally robust high-field magnet assembly that is passively protected against quench failure situations.

[0006]

[0006] In embodiments, the concepts described can facilitate the commercialization of high-field magnets for use in fusion power facilities (e.g., small fusion power facilities) and in high-energy physics applications. However, after reading the description provided herein, one of ordinary skill in the art will readily appreciate that the disclosed concepts are generally applicable to use in a wide range of other applications where high-field magnets can be used (e.g., a wide range of industrial uses). Such applications include, but are not limited to, uses in the medical and life science fields (e.g., magnetic resonance imaging and spectroscopy); uses in the fields of chemistry, biochemistry, and biology (e.g., nuclear magnetic resonance (NMR), NMR spectroscopy, electron paramagnetic resonance (EPR), and Fourier transform ion cyclotron resonance (FT-ICR)); uses in particle accelerators and detectors (e.g., for use in healthcare applications such as in equipment for radiation therapy); uses in devices for the generation and control of high-temperature hydrogen plasmas; uses in the realm of transportation; uses in the realm of power generation and conversion; uses in heavy industry; uses in weapons and defense; and uses in the realm of high-energy particle physics.

[0007] According to one aspect of the concepts described herein, a high magnetic field magnet assembly includes a plurality of conductive plates, each of the plurality of conductive plates having a spiral groove provided therein, and the plurality of conductive plates are arranged (e.g., stacked) to form a one-piece pancake assembly having a first outermost surface and a second opposite outermost surface. The high magnetic field magnet assembly further includes a non-insulated (NI) HTS tape stack disposed within a channel formed by the grooves of the first and second conductive plates. In an embodiment, the HTS stack may include a co-wind material that may comprise one or a combination of a non-insulating material, an insulating material, or a semi-conductive material. In an embodiment, the channel may be sized to enclose two or more stacks, and a separate structure optionally mechanically engageable with the plates is disposed between the stacks. The channel has a first opening on the first outermost surface of the pancake assembly and a second opening on the second opposite outermost surface of the pancake assembly. The NI HTS tape (and the co-wind stack when included) is continuously disposed within the channel such that the NI HTS tape (and co-wind stack) forms a path from the first outermost surface of the pancake assembly to the second opposite outermost surface of the pancake assembly.

[0008] In an embodiment, a pair of spiral-grooved plates (e.g., an upper plate and a lower plate) are stacked to form a one-piece double pancake assembly.

[0009] In an embodiment, two identical spiral-grooved plates are assembled back-to-back, and an insulating material is inserted or otherwise disposed between the plates. One or more HTS tape stacks with co-winding are disposed into grooves aligning an inward spiral on the upper plate, a helix to the lower plate, and an outward spiral on the lower plate.

[0010]

[0010] In an embodiment, the high magnetic field magnet assembly can include a co-wound material and a surface coating that are selected to provide a desired (and ideally, optimized) magnet quench behavior.

[0011]

[0011] In an embodiment, the high magnetic field magnet assembly is prepared from a composite of a base material that is selected to provide a desired (and ideally, optimized) magnet quench behavior. It can include a spiral-grooved plate and a surface coating (electrically insulating, conductive, and / or semiconductive).

[0012]

[0012] In an embodiment, a bladder element can be included within the tape stack to preload the stack prior to soldering, or to eliminate the need for soldering.

[0013]

[0013] In an embodiment, the bladder element may be filled with a material that is liquid during assembly but solid at the magnet operating temperature. The heat of fusion associated with this material can act as a large thermal reservoir to protect the HTS during a quench event.

[0014]

[0014] In an embodiment, a copper spiral lid can be soldered, or otherwise joined or affixed, to the tape bundle to assist in facilitating heat removal to a coolant channel plate stacked on top of the spiral.

[0015]

[0015] In an embodiment, grooves can be machined into the upper surface of the copper spiral lid and the base plate along and / or across the path of the spiral winding to facilitate coolant passage.

[0016]

[0016] In an embodiment, a copper interconnect between a pancake with inward-facing spiral grooves and a pancake with outward-facing spiral grooves may be used. This copper interconnect may be used at both the inner diameter (ID) and outer diameter (OD) of each spiral groove winding plate. In this case, the magnet assembly is constructed by simply stacking on top of each other a series of plates filled with HTS with spiral grooves that are alternately arranged with coolant channel plates, and / or by using coolant channel grooves cut into the surface of the plates as described above, and simply stacking on top of each other a series of plates filled with HTS with spiral grooves.

[0017]

[0017] In an embodiment, the HTS and the co-wound stack are embedded within a matrix of copper or other high electrical conductivity material where it enters and exits the spiral groove winding plate, and where the stack transitions from one spiral groove winding plate to another. This helps to protect the HTS against overheating and damage during magnet charging and magnet quench situations.

[0018] In another aspect of the concepts described herein, the magnet assembly of stacked plates comprises a first plate, a second plate disposed above the first plate, an electrical insulating material disposed between the first and second plates, and one or more HTS tape stacks, each of which may include co-wound material (conductive, electrically insulating, and / or semiconductive). The first plate is provided with at least one spiral-shaped groove provided therein. The second plate may further be provided with at least one spiral groove provided therein such that when the first surface of the first plate is disposed above the first surface of the second plate, the grooves form a channel having a spiral shape directed inward on the first plate, a helix to the second (or lower) plate, and a spiral directed outward on the lower plate. The electrical insulating material is disposed between the first and second plates. The HTS tape stack with co-winding is disposed within the channel such that this enables a winding having a spiral shape. While the winding will generally be of a spiral shape, it should be appreciated that the magnet core may be provided having a D shape, a solenoid shape, a circular shape, or any other shape suitable for the application for which the magnet core is to be used. Similarly, the helical channel can be deformed into the shape required to facilitate a continuous channel that allows the HTS tape stack to pass from the first plate to the second plate. After reading the description provided herein, one of ordinary skill in the art will appreciate how to select the appropriate winding and magnet shape for the needs of an individual application. It can be deformed into the shape required to facilitate a continuous channel that allows the HTS tape stack to pass from the first plate to the second plate. After reading the description provided herein, one of ordinary skill in the art will appreciate how to select the appropriate winding and magnet shape for the needs of an individual application.

[0019]

[0019] In one embodiment, the grooves in the first and second plates are substantially the same. The first and second plates may further have substantially the same spiral-shaped grooves and may be assembled back-to-back.

[0020]

[0020] The channels form a spiral that goes inward on the upper plate, a helix to the lower plate, and a spiral that goes outward on the lower plate. An HTS tape laminate that may include co-wound material can be inserted into the grooved channels. The co-wound material and the surface coating can be selected to optimize the magnet quench behavior.

[0021]

[0021] In an embodiment, a bladder element can be included as co-wound material within the HTS tape laminate. The bladder element can be configured within the HTS tape laminate to pre-load the HTS tape laminate prior to soldering. In an embodiment, the bladder element can further be configured within the HTS tape laminate to eliminate the need for soldering. The bladder element can further be configured to pre-compress the HTS tape laminate against the load-bearing sidewalls of at least one spiral groove.

[0022]

[0022] In an embodiment, the bladder element may be filled with a material that is liquid during assembly but solid at the magnet operating temperature. One such material includes, but is not limited to, gallium. The heat of fusion associated with this material can act as a large thermal reservoir to limit the temperature rise of the HTS during a quench event.

[0023]

[0023] In an embodiment, the number, size, and type of HTS tapes within the laminate with optional co-wound material can be varied by location along the spiral path, if desired, to save cost and / or to optimize the magnet quench response, among other things.

[0024]

[0024] The magnet can further comprise at least one coolant channel. In an embodiment, the at least one coolant channel can be provided in one or both of the first and second plates. In an embodiment, the coolant channel can include one or more coolant paths extending along the HTS tape stack. In other embodiments, the at least one coolant channel can include one or more coolant channel plates that are alternately arranged with one or both of the first and second plates or are sandwiched within such a stack of plates that can comprise a magnet assembly. In such embodiments, the coolant channel path need not extend along the HTS tape stack. In some embodiments, the coolant channel is formed by cutting a groove in the surface of the plate, including a copper lid disposed above the HTS tape stack. Such a coolant channel groove need not extend along the HTS tape stack.

[0025]

[0025] The magnet can further comprise a conductive plate disposed between the first and second plates or sandwiched within such a stack of plates that can comprise a magnet assembly. The conductive plate can be provided from any conductive material, including but not limited to copper. The conductive plate can further be provided from a thermally conductive material and can be configured to provide conduction cooling.

[0026]

[0026] In addition, the magnet can comprise one or more electrical interconnects between the first and second plates, and such one or more electrical interconnects are configured to establish and maintain a high electrical resistance in some regions to minimize the flow of bypass current between each of the winding plates during magnet charging.

[0027] ​

[0027] In another aspect, a method for constructing a high magnetic field magnet includes assembling a series of spiral-grooved plates filled with HTS, stacked between coolant channel plates, and forming one or more inter-pancake electrical connections, each of the one or more inter-pancake connections having low electrical resistance characteristics. The step of forming one or more inter-pancake connections can include automatically forming the one or more inter-pancake connections.

[0028]

[0028] The method can further include applying a preload to the HTS tape stack within the spiral-grooved plate to eliminate the need for soldering.

[0029]

[0029] In another aspect of the concepts described herein, a magnet assembly includes a first conductive plate having a first surface with a plurality of grooves provided therein, the grooves defined by one or more walls, at least two of the plurality of grooves having different widths, the first conductive plate, and a non-insulated (NI) high temperature superconductor (HTS) tape stack having a predetermined length such that the NI HTS tape stack forms a continuous path between the outermost groove in the first conductive plate and the innermost groove of the first conductive plate and is disposed within the plurality of grooves. In an embodiment, the HTS tape is configured within each groove such that in response to a generated force, the HTS tape stack distributes the force into the first and second conductive plates.

[0030]

[0030] In an embodiment, the magnet assembly further includes a second conductive plate such that when the first surface of the first plate is disposed above the first surface of the second plate, the grooves form channels having an opening at a first end of the channel, and the HTS tape is disposed above the first conductive plate to form a continuous path between the first conductive plate and the second conductive plate.

[0031]

[0031] In an embodiment, the HTS tape laminate is disposed in one of a plurality of grooves of varying widths and is wound around the HTS tape laminate itself so as to occupy the width of the groove.

[0032]

[0032] In an embodiment, the wall defining the groove in the first conductive plate is provided with a variable wall thickness such that the thickness of a first portion of the wall is different from the thickness of a second portion of the same wall.

[0033]

[0033] In an embodiment, the wall defining the groove in the first conductive plate is provided with different wall thicknesses.

[0034]

[0034] In an embodiment, the thickness of a first portion of the first wall in a first radial direction as measured from the center of the first conductive plate is different from the thickness of a first portion of a second different wall along the same first radial direction.

[0035]

[0035] In an embodiment, the first and second conductive plates have substantially the same spiral-shaped grooves.

[0036]

[0036] In an embodiment, the NI HTS tape laminate is composed of two or more NI HTS tape laminates joined by low-resistance electrical connections.

[0037]

[0037] In an embodiment, the material comprising the NI HTS tape laminate in the first and second plates is continuous across the plates.

[0038]

[0038] In an embodiment, the NI HTS tape laminate further comprises a co-wound material disposed in the groove such that the HTS tape and the co-wound laminate follow a path between the outermost first groove of the first conductive plate and the innermost groove of the first conductive plate, and the HTS tape and the co-wound laminate are configured in the groove to distribute force into the first and second conductive plates in response to the force generated.

[0039]

[0039] In an embodiment, the co-wound material is provided as one or more of a conductive material, an electrically insulating material, and / or a semiconductive material.

[0040]

[0040] In an embodiment, the co-wound material is selected to optimize the magnet quench behavior, or the magnet charging behavior, or both.

[0041]

[0041] In an embodiment, the HTS tape and the co-wound stack pass between the plates on which they are stacked; the HTS tape and the co-wound stack enter into and exit from the magnet assembly; and the electrical interconnects are embedded within the parent material of a high electrical conductivity material at locations where they are formed between the windings.

[0042]

[0042] In an embodiment, the co-wound material varies either in composition or thickness along the length of the NI HTS tape stack.

[0043]

[0043] In an embodiment, the electrically insulating material is disposed in a selected area between the plates to be stacked.

[0044]

[0044] In an embodiment, the NI HTS tape stack includes one or more HTS tapes, and the number, size, and type of the HTS tapes within the NI HTS tape stack vary along the length of the NI HTS tape stack.

[0045]

[0045] In an embodiment, the groove defines a spiral that goes inward on the first conductive plate, the inward spiral has a first end and a second end, the first electrical plate has a helical opening provided therein, the helical opening has a first end and a second end, the first end of the helical opening is coupled to the second end of the inward spiral, and the second end of the helical opening leading to the second conductive plate is coupled to the first end of an outward spiral provided within the second conductive plate.

[0046]

[0046] In an embodiment, the bladder element is included within the HTS tape stack. In an embodiment, the bladder element is configured to pre-compress the HTS tape stack against the load-bearing sidewalls of at least one spiral groove. In an embodiment, the bladder element encapsulates a material that is liquid or gaseous during magnet assembly and is solid or liquid or gaseous, or is discharged, during magnet operation. In an embodiment, the bladder element encapsulates a material that exhibits a phase change from solid to liquid and / or from liquid to gas during magnet operation.

[0047]

[0047] In an embodiment, the first conductive plate has at least one coolant channel provided therein. In an embodiment, the coolant channel includes one or more coolant paths disposed along the HTS tape stack. In an embodiment, the at least one coolant channel includes one or more coolant channel plates that are alternately disposed with one or both of the first plate and the second conductive plate. In an embodiment, the at least one coolant channel includes one or more coolant paths disposed along a path different from the path of the HTS tape stack. In an embodiment, the conductive plate can be inserted between the first conductive plate and the second conductive plate.

[0048]

[0048] In an embodiment, a high electrical conductivity coating can be disposed on at least one selected location of the first and second conductive plates.

[0049]

[0049] In an embodiment, the conductive plate wholly or partially includes copper.

[0050]

[0050] In an embodiment, the conductive plate wholly or partially includes copper.

[0051]

[0051] Some embodiments relate to an apparatus comprising a conductive plate having a groove and a high temperature superconductor (HTS) tape stack disposed within the groove, the HTS tape stack having a spiral shape.

[0052]

[0052] The groove may have a spiral shape.

[0053]

[0053] The conductive plate may include a metal or a metal alloy.

[0054]

[0054] The device may further include a coolant channel.

[0055]

[0055] The coolant channel may be disposed within the groove.

[0056]

[0056] The coolant channel may be disposed outside the groove.

[0057]

[0057] The HTS tape stack may be a non-insulated HTS tape stack.

[0058]

[0058] The HTS tape stack may include a plurality of windings, and the conductive plate provides an electrical connection between each winding of the plurality of windings.

[0059]

[0059] The device may further include a shim or a blada within the groove.

[0060]

[0060] The conductive plate may be a first conductive plate, the groove may be a first groove, the HTS tape stack may be a first HTS tape stack, and the device may further include a second conductive plate having a second groove and a second HTS tape stack disposed within the second groove and having a spiral shape, and the first HTS tape stack is electrically coupled to the second HTS tape stack.

[0061]

[0061] The first conductive plate may be electrically insulated from the second conductive plate.

[0062]

[0062] When the first and / or second conductive plates are grouped together, the first and second conductive plates have one or more alignment structures for aligning the first and second conductive plates.

[0063]

[0063] The device may further include a conductive connection portion between the first HTS tape stack and the second HTS tape stack.

[0064]

[0064] The conductive connection portion may include a high-temperature superconductor or a metal that is not a superconductor at a temperature above 30 Kelvin.

[0065]

[0065] The conductive connection portion may include copper.

[0066]

[0066] The conductive connection portion may be formed between the innermost windings of the first and second HTS tape stacks or between the outermost windings of the first and second HTS tape stacks.

[0067]

[0067] The first HTS tape stack and the second HTS tape stack may be the same HTS tape stack.

[0068]

[0068] The transition portion between the first HTS tape stack and the second HTS tape stack may be formed by a helical portion of the same HTS tape stack.

[0069]

[0069] The first groove may include at least the first and second windings. The first winding has a first width, the second winding has a second width, and the second width is greater than the first width.

[0070]

[0070] The second winding of the groove may include a plurality of windings of the HTS tape stack.

[0071]

[0071] The device may include a magnet.

[0072]

[0072] The HTS tape stack may include a rare earth oxide.​

[0073]

[0073] The HTS tape laminate may contain a rare earth barium copper oxide.

[0074]

[0074] The device may further include a conductive terminal block electrically coupled to the HTS tape laminate.

[0075]

[0075] Some embodiments relate to a manufacturing method including the steps of forming a conductive plate having a groove and disposing a high temperature superconductor (HTS) tape laminate in a spiral shape within the groove.

[0076]

[0076] The foregoing and other objects, features, and advantages will become apparent from the following more detailed description of embodiments, as illustrated in the accompanying drawings in which like reference numerals refer to the same parts throughout different views. The drawings are not necessarily to scale, and instead emphasis is placed on illustrating the principles of the embodiments.

Brief Description of the Drawings

[0077]

Figure 1

[0077] An isometric view of a portion of a double pancake magnet assembly of stacked plates with spiral grooves, which may be the same as or similar to the double pancake magnet assembly of stacked plates with spiral grooves shown in FIG. 1C.

Figure 1A

[0078] An isometric view of a portion of a double pancake magnet assembly of stacked plates with spiral grooves, which may be the same as or similar to the double pancake magnet assembly of stacked plates with spiral grooves shown in FIG. 1C.

Figure 1B

[0079] An isometric view of a portion of a double pancake magnet assembly of stacked plates with spiral grooves, which may be the same as or similar to the double pancake magnet assembly of stacked plates with spiral grooves shown in FIG. 1C.

Figure 1C

[0080] Isometric view of a double pancake magnet assembly of stacked plates with spiral grooves.

Figure 2

[0081] A series of cross-sectional views of a plate with spiral grooves showing options for coolant channels extending along the HTS tape.

Figure 2A

Figure 3

[0082] Cross-sectional view of two plates having spiral grooves provided therein, said plates being stacked with respect to a shared coolant channel plate or a conduction-cooled plate.

Figure 3A

[0083] Cross-sectional view of two plates having spiral grooves provided therein, said plates being stacked with respect to a shared coolant channel plate or a conduction-cooled plate and having copper interconnects between the pancakes fabricated within regions of those two plates.

Figure 4

[0084] Cross-sectional view of a magnet having a hydraulic bladder.

Figure 5

[0085] A series of cross-sectional views of a magnet illustrating the selection of materials, coatings, and insulators in co-wound tape stacks and spiral grooves that can be used to control the heat application region of a magnet quench.

Figure 5A

Figure 6

[0086] Cross-sectional view of a spiral-grooved magnet plate assembly taken in the direction across line 6-6 of the spiral-grooved plate shown in FIG. 6A.

Figure 6A

[0087] Top view of the first spiral-grooved plate.

Figure 6B

[0088] Top view of a channel plate having an insulating radial coolant channel provided therein.

Figure 6C

[0089] Top view of a second plate with spiral grooves.

Figure 7

[0090] Top view of a double - pancake magnet assembly of stacked plates with variable - width spiral grooves.

Figure 7A

[0091] Cross - sectional view of the double - pancake magnet assembly of stacked plates with variable - width spiral grooves of FIG. 7 taken along line A - A of FIG. 7.

Figure 7B

[0092] Cross - sectional view of the double - pancake magnet assembly of stacked plates with variable - width spiral grooves of FIG. 7 taken along line B - B of FIG. 7.

Figure 7C

[0093] Cross - sectional view of the double - pancake magnet assembly of stacked plates with variable - width spiral grooves of FIG. 7 taken along line C - C of FIG. 7.

Figure 7D

[0094] Perspective view of a portion of the double - pancake magnet assembly 7 of stacked plates with variable - width spiral grooves taken along line A - A of FIG. 7.

Mode for Carrying Out the Invention

[0078]

[0095] Described herein are concepts and techniques for enabling high-field magnets. Described herein are structures and techniques for the design and construction of high-field magnets having a relatively small size and shape. The concepts, structures, and techniques described provide means for constructing robust high-field superconducting magnets using fabrication techniques that are relatively simple compared to prior art high-field magnet fabrication techniques. Furthermore, the concepts, structures, and techniques described can utilize modular components that scale well towards commercialization. The high-field magnet assemblies described can utilize stacked plates with spiral grooves and non-insulated high-temperature superconducting (HTS) tape. The non-insulated tape allows current to flow from one winding to the outer winding of the tape of the superconductor, without the need for, but sometimes without, an insulating material. Such an approach can inherently result in a structurally strong magnet assembly, which allows for high (and ideally, maximum) utilization of the high magnetic fields available by HTS technology. Furthermore, the use of stacked plates with spiral grooves and non-insulated HTS tape stacks (or HTS tapes and co-wound stacks with conductive, non-conductive, and / or semiconductive materials) disposed within the spiral grooves can allow for the inclusion of coolant paths, which in some cases can be optimized coolant paths.

[0079]

[0096] The HTS tape includes an HTS material. As used herein, the phrase "HTS material" or "HTS superconductor" refers to a superconducting material having a critical temperature above 30K in its self-field. Examples of HTS superconductors include, but are not limited to, rare earth oxides, such as rare earth barium copper oxides (REBCO).

[0080]

[0097] A pancake assembly is provided in which the HTS is self-wound. The HTS tapes themselves (including optional co-winds) associated with the grooved plate provide the mechanical strength required to generate a high magnetic field. In embodiments, the spiral preferably has a circular geometry, of course. As a result of the HTS tapes themselves providing the essential mechanical strength, such coils are easy to construct and mechanically strong. For example, an 8 Tesla double pancake non-insulated (NI) HTS tape coil was designed, constructed, and successfully operated within less than six months. In some embodiments, the NI HTS tape (and co-wind stack when used) forms a continuous path from the first outermost surface of the pancake assembly to the second outermost surface on the opposite side of the pancake assembly. However, it should be appreciated that in some embodiments, the path of one material may be interrupted and not continuous. Thus, it should be appreciated that the grooved path is at least somewhat continuous, but the material disposed within the grooved path may not be continuous.

[0081]

[0098] The NI HTS pancakes are of particular interest because they have unique current shunting characteristics / phenomena during a magnet quench. Specifically, since the HTS tape (or tape stack) is not insulated or only partially insulated, Joule heating can be distributed somewhat uniformly throughout the winding. It is desirable to optimize and fully utilize this behavior by devising a robust, passively protected magnet design that can operate at high energy density. The spiral-grooved plate assembly configuration described herein can control the distributed quench drive current in the coil structure and reduce (and ideally minimize) the magnitude and duration of the current shunting current and, therefore, the Joule heating and temperature rise of the HTS tape stack itself. Furthermore, the current is electromagnetically coupled to the spiral-grooved plate and other surrounding structures, which, by careful selection of the magnet design, may further lead to a uniform current distribution and a reduced temperature rise due to Joule heating, because the magnetic field energy can be dissipated in a much larger volume of material compared to prior art techniques.

[0082]

[0099] In addition, the concepts, structures, and techniques described enable control of the quench-induced current distribution in the HTS tape stack and the surrounding upper structure to safely dissipate the quench energy while simultaneously obtaining an acceptable magnet charge time. The end result is a structurally and thermally robust high-field magnet assembly that is passively protected against quench failure situations.

[0083]

[0100] Fusion power plants (e.g., small fusion power plants) and fusion research experiments (e.g., Although references to the use of such high magnetic field magnet assemblies as being related to, e.g., SPARC, are sometimes made herein, such references are not intended to be limiting and should not be construed as limiting. The high magnetic field magnet assemblies enabled by the concepts described herein find use in a variety of applications including, but not limited to, applications in the field of high energy physics, applications in the fields of medicine and life sciences, applications in the fields of chemistry, biochemistry, and biology, applications in the fields of particle accelerators and detectors, applications in the field of devices for the generation and control of high temperature hydrogen plasmas, applications in the field of transportation, applications in the field of power generation and conversion, applications in heavy industry, applications in weapons and defense, as well as it is recognized that they find use in a wide variety of applications including, but not limited to, applications in the field of high energy particle physics.

[0101] For example, in the fields of medicine and life sciences, the concepts described herein The high magnetic field magnets enabled by [the relevant technology] can be found in use in magnetic resonance imaging (MRI) and spectroscopy. In the fields of chemistry, biochemistry, and biology, the high magnetic field magnets enabled by the concepts described herein can be found in use in nuclear magnetic resonance (NMR), NMR spectroscopy, electron paramagnetic resonance (EPR), and Fourier transform ion cyclotron resonance (FT-ICR). In the realm of particle accelerators and detectors, the high magnetic field magnets enabled by the concepts described herein can be found in use in healthcare applications such as in equipment for radiation therapy and in charge particle beam transmission (e.g., from an accelerator to a target / patient). In the realm of transportation, the high magnetic field magnets enabled by the concepts described herein can be found in use in high power density motors, generators, and MHD propulsion (e.g., in electric aircraft, maglev trains, hyperloop concepts, railway engines and transformers, ship propulsion and generators, and vehicles). In the realm of utilities and power applications, the high magnetic field magnets enabled by the concepts described herein can be found in use in electrical machinery, power generation and power conversion systems (e.g., wind turbines, transformers, synchronous condensers, utility generators producing up to or greater than 300 MW such as those producing 300 MW or more, superconducting energy storage, and MHD energy generation). The high magnetic field magnets enabled by the concepts described herein can be found in use in the realm of heavy industrial applications (e.g., large industrial motors, magnetic separation, disposable mixing systems, induction heaters). In the realm of weapons and defense applications, the high magnetic field magnets enabled by the concepts described herein can be found in use in propulsion motors and generators, electromagnetic pulse (EMP) generation, power supplies for directed energy weapons, and in railguns / coilguns.

[0084]

[0102] One or more HTS tes arranged within a spiral groove or channel References to wound - up assemblies, or HTS wound - up assemblies and co - windings, are sometimes made herein. As used herein, the term "HTS tape wound - up assembly" is to be understood to include a "wound - up assembly" having multiple layers of HTS tape, or only a single layer of HTS tape, and, optionally, one or more tapes made of non - HTS materials which are herein referred to as "co - winding" tapes. The number, size, and type of tape layers to be used in any individual HTS tape wound - up assembly are selected according to the requirements of the individual application. For example, in an application that only requires low current capacity and can accept high inductance characteristics, a single - layer tape wound - up assembly may be used. However, in high - current / low - inductance applications (e.g., small - scale fusion applications), HTS tape wound - up assemblies prepared from a single layer or multiple individual layers of HTS tape up to many individual layers (e.g., in the range of 10 to 1000 layers, or more) may be used. In cases where multiple HTS tape layers are included within an HTS tape wound - up assembly, the multiple layers of HTS tape are essentially joined in parallel to enable a structure with increased current - carrying characteristics relative to a single HTS tape layer.

[0085]

[0103] Like elements are given like reference numerals throughout several views Referring now to FIGS. 1 - 1C, a series of views illustrate the use of a stacked - plate concept with spiral grooves used to form a so - called one - piece "double - pancake assembly" 100 (FIG. 1A). It should be appreciated that details of the current lead connections are omitted for clarity in the description and drawings.

[0086]

[0104] In an overall overview, FIGS. 1 - 1C illustrate an example of a spiral - grooved plate that can be stacked to form an integral so - called "double - pancake" assembly 100. In the illustrated example, two (optionally identical) plates with spiral grooves (Figure 1) are assembled back-to-back, and an insulating material is inserted between or otherwise disposed between those plates (Figure 1A). An HTS tape laminate that may include co-wound material is inserted into a grooved channel (Figure 1B) that can align an inward spiral on the upper plate, a helix to the lower plate, and an outward spiral on the lower plate. In some embodiments, the HTS tape laminate is wound continuously (i.e., without interruption or subdivision) from the upper surface to the lower surface of the pancake assembly. In some embodiments, the NI HTS tape (and co-wound laminate when used) may be subdivided or otherwise have interruptions provided therein (e.g., the path of one material may be interrupted and not continuous). While the grooved path may be described as being at least somewhat continuous (even though the cross-sectional shape may vary throughout the length of the grooved path), it should thus be appreciated that the material packed or otherwise disposed within the grooved path may be continuous or may be provided in parts (e.g., subdivided). In some embodiments, two or more HTS tape laminates may be disposed into the grooves with material disposed between the laminates, and that material may mechanically engage the plates, such as by the spiral grooves, either separately or in association with the tape laminate. In some embodiments, some or all of the co-wound material may be disposed to mechanically engage the plates, such as by the spiral grooves, either separately or in association with the tape laminate.

[0087]

[0105] The co-wound material and surface coating are desired (and ideally, optimized (Ru) It can be selected to bring about magnet quench behavior. In an embodiment, the braider element can also be included within the tape stack to apply a preload to the stack prior to soldering or to eliminate the need for soldering. A copper (or other high thermal conductivity material) spiral lid (Figure 1C) can be soldered, or otherwise joined or affixed to the tape bundle to assist in facilitating heat removal to the coolant channel plate stacked on top of the spiral (see Figures 3 and 6, which will be described in detail below). Another embodiment uses a copper interconnect between a pancake with inward spiral grooves and a pancake with outward spiral grooves (see Figure 3). This copper interconnect can be used at both the inner diameter (ID) and outer diameter (OD) of each spiral-grooved winding plate. In this case, the magnet assembly can be constructed by simply stacking a series of plates filled with HTS with spiral grooves, arranged alternately with coolant channel plates, on top of each other (e.g., similar to that shown and described in connection with Figure 6 below, but without the external connections between the double pancakes). Depending on the application, the coolant channel plate can be replaced by a conduction cooling plate or eliminated altogether.

[0088]

[0106] An exemplary stacked plate double pancake magnet assembly 100 (Figure 1A) is the first It includes a first plate 105 (FIG. 1) having two opposite surfaces 105a, 105b and a groove 125. The first plate 105 includes, or can be formed from, any conductive material including, for example, a metal or an alloy. Such materials include, but are not limited to, one or more of nickel-based superalloys such as Inconel 718 and Hastelloy C276, austenitic stainless steels, and dispersion-strengthened copper alloys. Factors influencing material selection include, but are not limited to, mechanical strength, electrical conductivity, thermal conductivity, and coefficient of thermal expansion. Composite materials of different materials can be used. The material can be selected to optimize the uniformity of quench energy imparted, the structural integrity under load and under unusual circumstances, and to minimize cost. Additive manufacturing techniques can be readily used to fabricate the plate geometries on which the magnets can be constructed.

[0089]

[0107] A groove 125 is provided, which is initially helical as the groove enters the plate The shape can be, and then have a spiral shape within the plate. In this exemplary embodiment, the spiral is provided as a curvilinear spiral (i.e., a substantially continuous and radially expanding or contracting curve either around a central point on a flat plane or around an axis so as to form a cylinder). In other embodiments, it should be appreciated that a shape similar to a spiral can be used (i.e., a winding body forming an overall expanding or contracting path either around a central point on a flat plane or around an axis). As used herein, the term "spiral shape" includes "spiral-like" shapes. For example, in some embodiments, it may be desirable or necessary to utilize a shape similar to a rectangular spiral. In still other embodiments, it may be desirable or necessary to utilize a shape similar to a triangular spiral. In still other embodiments, it may be desirable or necessary to utilize a shape similar to an oval spiral. Other spiral-like shapes, including geometrically irregular shapes, may further be used. After reading the disclosure provided herein, one of ordinary skill in the art will appreciate how to select an individual spiral or spiral-like geometric form / shape for use in an individual application. It should further be appreciated that the spiral or spiral-like grooves can be provided with a constant pitch (i.e., the same pitch) or can be provided with a variable pitch. The variable pitch can provide significant design flexibility, for example, by providing space between the windings to receive coolant passages between the pancake plates and / or increasing the strength of the pancake in certain areas while reducing the overall magnet weight and / or enabling a more uniform quench energy deposition.

[0090]

[0108] The first plate 105, in this exemplary embodiment, the first plate 105 to the second Included to assist in attaching to a plate (e.g., the second plate 110 of FIG. 1A) are optional interface apertures 120a-N. In some embodiments, the attaching can be performed by conventional fasteners as is generally known. In embodiments, other fastening techniques can be used to join or otherwise attach two or more plates. Such techniques include, but are not limited to, welding, soldering, and brazing. Features including, but not limited to, weld lips, flanges, weld reliefs, screw holes, rivets, and special attachment points can be added to the plate to accommodate the fastening techniques used in a commercial production environment.

[0091]

[0109] As will become apparent from the description in the following specification, groove 125 (FIG. 1) is configured to receive a high temperature superconductor (HTS) tape stack (e.g., the HTS tape stack 150 of FIG. 1C) in this embodiment. The HTS tape stack may be composed entirely of HTS tapes, or may include "co-wound" tapes that are separately sandwiched and / or stacked on top of the stack of HTS tapes, i.e., tapes made entirely of non-HTS materials. The co-wound material can be conductive, insulating, or semiconducting. In some embodiments, the electrical properties of the co-wound material can be selected to be advantageous for optimizing the quench behavior. In other embodiments, two or more stacks can be arranged in a groove, and a separating material is disposed therebetween. In this case, the dimensions of the groove that may include secondary grooves for engaging the separating material are appropriately modified. The co-wound tape may further include a "bladder" as further described below. Some of the factors considered in selecting the characteristics of the HTS tape include, but are not limited to, the operating current of the individual tape, the total current desired in the tape stack, the strain characteristics of the tape, and other mechanical characteristics. In some applications, it may be desirable to vary the number, size, and / or type of HTS tapes in the stack depending on the location along the path, for any of a variety of reasons, such as to save cost, size, and / or weight. The current shunting attribute of the stacked non-insulated HTS tapes with optional co-winding takes this possibility into account. For example, in a region of low magnetic field strength, the number of HTS tapes in the stack can be reduced, taking advantage of the fact that the operating current in the remaining HTS tapes can be increased. Factors influencing the selection of the HTS tape width include, but are not limited to, the Lorentz loading on the tape stack and the reaction load on the sidewalls of the grooved channel. Thus, the dimensions of the spiral groove in the plate are selected to accommodate the dimensions of the HTS tape stack that can vary in location.

[0092]

[0110] In an embodiment, the HTS tape stack has a spiral groove 130 (i.e., 3, is fed or otherwise disposed into the end of a so-called inwardly directed spiral groove 130).

[0093]

[0111] In the embodiment shown here, the alignment pins 115a-N are It is used to connect to an interface (eg, plate 110 in FIG. 1A) and maintain orientation.

[0094]

[0112] Referring briefly to FIG. 1A, a stacked plate double pancake magnet assembly 10 The second plate 110 of FIG. 0 is disposed above the first plate 105 such that the grooves 125 provided in each of the respective plates 105, 110 are aligned.

[0095]

[0113] The mating faces of the two spiral grooved plates are such that plates 105 and 110 are H The TS tape stacks may be partially electrically insulated from one another by the application of an insulating coating and / or insulating plate 140 (further depicted as 440 in FIG. 4) so ​​that they are electrically connected only across the contact area, including where the TS tape stack transitions from one plate to the other, 125.

[0096]

[0114] The second plate 110 has an inwardly directed channel having a generally spiral shape. Formed or otherwise provided is a groove 135 defining a spiral 136. As alluded to above in connection with groove 125, groove 135 is shown here having a generally curved spiral shape, although it should be appreciated that other spiral shapes may also be used, including but not limited to square, rectangular, triangular, or oval shapes. In the embodiment shown here, one end of groove 135 connects to a helical channel 137 that passes between plates 105 and 110.

[0097]

[0115] When the grooves in each plate are paired together, they form an inwardly directed Channels such as the spiral channel 136 can be formed. The inward spiral channel 136 receives the HTS tape and the co-wound laminate (e.g., the HTS tape and co-wound laminate 150 of FIG. 1C) that are fed into the helical channel 137. The helical channel 137 is coupled to the helical groove 125 of the first plate 105 such that the HTS tape laminate can be fed (or otherwise provided or oriented) through the helical channel 137 into the helical groove 125 of the first plate 105.

[0098]

[0116] In some embodiments, the material surrounding the helical channel is selected to have high thermal and electrical conductivity and can be, for example, copper. It should be appreciated that this concept allows for some flexibility in the selection of the material within this region, as well as the particular procedures by which the geometric form of the helical channel is formed and mechanically and electrically supported.

[0099]

[0117] In some embodiments, the HTS tape and co-wound laminate are embedded within copper, or other suitable high electrical conductivity material, over a wide area that includes where the HTS tape and co-wound laminate enter and exit the channels on each of the plates with spiral grooves and extends to the current feeder connection on the outside of the plate with spiral grooves without interruption. This helps protect the HTS from overheating and damage during magnet charging and magnet quench events.

[0100]

[0118] Referring now to FIG. 1B, the HTS tape laminate 150 that may include co-wound material is disposed within the inwardly directed spiral groove channel 135. A coolant channel 155 or a thermally conductive elongate member 155 (FIG. 1C) that contacts a separate coolant channel (not shown) is disposed on top of the HTS tape stack. The coolant channel or the thermally conductive elongate member 155 (FIG. 1C) is configured to enable the magnet assembly 100 to be properly cooled during all stages of magnetic operation, including, but not limited to, magnet charging where local joule heating would occur from the bypass current. In some embodiments, the coolant channel 155 or the thermally conductive elongate member 155 is omitted.

[0101]

[0119] Referring now to FIG. 1C, the second plate 110 has an HTS tape stack 150 disposed therein. The HTS tape stack 150 is inserted into or otherwise disposed within the spiral groove channels 135 and the helical grooves 137 (most clearly visible in FIG. 1B), which direct or otherwise orient the HTS tape stack 150 into the spiral groove channels 135 of the first plate 105.

[0102]

[0120] In embodiments, the first and second plates 105, 110 include, but are not limited to, superalloys such as Inconel 7 18, Hastelloy C276, as well as a variety of structural materials including, but not limited to, stainless steels such as 316, and dispersion strengthened copper alloys such as GRCop-84, or may be formed from them. In embodiments, it may be desirable to coat or otherwise dispose a material layer within the channels 130, 135. Such materials may include, but are not necessarily limited to, electrodeposited solder to aid in fabrication, semiconductor coatings of various thicknesses to control quench current distribution, copper plating / coatings, and / or ceramic coatings.

[0103]

[0121] In some embodiments, the channels 130, 135, and / or the overall The plate assemblies 105, 110 can be formed by additive manufacturing techniques such as three-dimensional (3-D) printing. Such techniques have already demonstrated the ability to fabricate structures of the required size and shape using a variety of structural materials such as superalloys like Inconel 718, Inconel 625, as well as 316 stainless steel and dispersion-strengthened copper alloy GRCop-84. Suffice it to say that a variety of additive manufacturing techniques can be used for fabrication using a variety of different materials.

[0104]

[0122] Significantly, in embodiments, the HTS tape stack and the co-winding 15 0 may not be insulated, may be partially insulated, and / or may contain a semiconductive material.

[0105]

[0123] The HTS tape stack may be composed entirely of HTS tape, or may include a "co-winding" tape that is separately sandwiched and / or stacked on top of the stack of HTS tapes, i.e., a tape made entirely of a non-superconducting material. The co-winding material may be conductive, insulating, or semiconductive, with electrical properties selected to be advantageous for optimizing the quench behavior. The co-winding tape may further include a "bladder" as further described below. In some embodiments, the HTS tape stack 150 may be formed outside the channel and then disposed within the channel. In other embodiments, elements of the HTS tape stack 150, including but not limited to those containing co-winding material, may be formed directly into the channels 13 0, 155, for example, by 3D printing techniques.

[0106]

[0124] In some embodiments, the cross-sectional shapes of the grooves in the first and second plates may be substantially the same. In other embodiments, the cross-sectional shapes of the grooves in the first and second plates may be different (e.g., to accommodate features such as structural elements that may be specific to the plate).

[0107]

[0125] Furthermore, in some embodiments, the first and second plates may further have substantially the same spiral-shaped grooves such that when the plates are assembled, the grooves form channels with their backs facing each other, i.e., in a configuration where the grooves are on opposite-facing surfaces. In other embodiments, the spiral shapes within each plate may be different. In embodiments, the channels form an inward spiral on the upper plate, a helix to the lower plate, and an outward spiral on the lower plate. The HTS tape stack and co-winding can be inserted into the channels. The co-winding material and surface coating can be selected to safely distribute the magnet quench energy within the volume of the structure.

[0108]

[0126] In some applications (e.g., the proposed toroidal field coil for the SPARC experiment), it may be necessary to remove heat (e.g., neutron-induced heating, copper joints) generated from a volume source within the region of the tape stack in order to maintain the operating temperature. The stacked plate approach with spiral grooves can readily accommodate this in several ways. FIGS. 2 and 2A illustrate two different embodiments with coolant channels disposed along the tape stack. Overall, the coolant channels are arranged beside (e.g., adjacent to, next to, or in the vicinity of) the main load path (e.g., the superconductor). The HTS tape plane coated with copper can be oriented orthogonal to the coolant channels, which maximizes heat transfer. FIG. 3 illustrates an alternative approach using coolant channel plates within the stack that are shared between opposite-facing pancakes. In embodiments, the channels form an inward spiral on the upper plate, a helix to the lower plate, and an outward spiral on the lower plate. The HTS tape stack and co-winding can be inserted into the channels. The co-winding material and surface coating can be selected to safely distribute the magnet quench energy within the volume of the structure.

[0109]

[0127] In some applications (e.g., the proposed toroidal field coil for the SPARC experiment), it may be necessary to remove heat (e.g., neutron-induced heating, copper joints) generated from a volume source within the region of the tape stack in order to maintain the operating temperature. The stacked plate approach with spiral grooves can readily accommodate this in several ways. FIGS. 2 and 2A illustrate two different embodiments with coolant channels disposed along the tape stack. Overall, the coolant channels are arranged beside (e.g., adjacent to, next to, or in the vicinity of) the main load path (e.g., the superconductor). The HTS tape plane coated with copper can be oriented orthogonal to the coolant channels, which maximizes heat transfer. FIG. 3 illustrates an alternative approach using coolant channel plates within the stack that are shared between opposite-facing pancakes. In some applications (e.g., the proposed toroidal field coil for the SPARC experiment), it may be necessary to remove heat (e.g., neutron-induced heating, copper joints) generated from a volume source within the region of the tape stack in order to maintain the operating temperature. The stacked plate approach with spiral grooves can readily accommodate this in several ways. FIGS. 2 and 2A illustrate two different embodiments with coolant channels disposed along the tape stack. Overall, the coolant channels are arranged beside (e.g., adjacent to, next to, or in the vicinity of) the main load path (e.g., the superconductor). The HTS tape plane coated with copper can be oriented orthogonal to the coolant channels, which maximizes heat transfer. FIG. 3 illustrates an alternative approach using coolant channel plates within the stack that are shared between opposite-facing pancakes.

[0110]

[0128] FIGS. 2 and 2A show cross-sections of the plates with the grooves seated in recesses within the plates. This plate , in contrast to the plates of FIGS. 1-1C, where the groove walls are above the main surface of the plate. Referring now to FIG. 2, the plate 205a with spiral grooves includes a groove or channel 230. In this exemplary embodiment, the channel 230 is provided with a rectangular cross-sectional shape. In other embodiments, the channel 230 may be provided with other cross-sectional shapes (i.e., other than rectangular) including, but not limited to, square, triangular, oval, or rounded, or other regular geometric shapes. The cross-sectional shape of the channel may be selected to be complementary to the shape of the HTS tape and vice versa. Ideally, but optionally, the HTS tape (or a combination of HTS tapes, and co-wound and / or shims and / or blading devices) substantially occupies the cross-section of the channel. Generally, it is desirable but optional for the channel 230 to be filled with a material having as high a mechanical strength, high thermal heat capacity, high thermal conductivity, and electrical properties optimized for magnet quench response as possible (e.g., to the extent possible given material properties, and / or mechanical and / or manufacturing tolerances, and / or manufacturing techniques).

[0111]

[0129] In this exemplary embodiment, the plate 205a has a width 233 of about 15 mm. The channel 230 has a depth of about 11 mm into the plate 205a. The channel further has a length 234 of about 9 mm. Inserted into or otherwise disposed within the channel 230 is an HTS tape stack 250 having a width 231 of about 6 mm and a length 232 of about 8.33 mm. Here, a wedge-shaped shim 235 is provided for the HT The S tape stack 250 is inserted or otherwise arranged into the groove 230 such that it is pressed against the sidewalls of the groove. In this illustrative embodiment, one of the channels is formed or otherwise provided at a distance 239 of about 4.25 mm from the surface of the plate 205a. However, these dimensions are merely illustrative as the structures described herein can have any of a variety of suitable dimensions.

[0112]

[0130] In an embodiment, the magnet assembly further comprises one or more coolant channels. In embodiments, the one or more coolant channels may be provided in one or both of the first and second plates. In embodiments, the one or more coolant channels may include one or more coolant passages disposed proximate to the HTS tape stack. In other embodiments, the one or more coolant channels may include one or more cooling channel plates interleaved or otherwise distributed between the plates that make up the high field magnet assembly.

[0113]

[0131] A coolant channel 215 is provided adjacent the HTS tape stack 250. In this illustrative embodiment, the coolant channel 215 is formed or otherwise defined by a thermally conductive member 210 having a C-shape (e.g., a C-shaped channel member 210) positioned on top of the HTS tape stack 250. In this illustrative embodiment, the coolant channel is approximately 30 mm long. 2It is provided with an area. However, this area is merely illustrative, because any suitable coolant channel area can be used. The thermally conductive member 210 may include one or more of copper, copper alloy, and high thermal conductivity materials. The coolant channel 215 is covered or otherwise closed (or capped) using a lid 220 that is fixed (e.g., welded or otherwise fixed) onto the plate 205a. The lid 220 is configured to enclose the HTS tape stack 250 and the coolant channel 215 within the groove 230. In one embodiment, a tape stack having a length of about 8 mm can be prepared from about 190 HTS tapes each 6 mm wide. In an embodiment, a superalloy (e.g., Hastelloy) can be used as a co-wound material to achieve the above 8 mm length with a reduced number of HTS tapes.

[0114]

[0132] In an embodiment, a plurality of plates with spiral grooves can be used, and high A method for constructing a high magnetic field magnet includes assembling a series of spiral-grooved plates filled with HTS that are stacked between coolant channel plates, and forming one or more inter-pancake electrical connections, each of the one or more inter-pancake connections having low electrical resistance characteristics such that the resulting Joule heating can be received by the coolant system. In an embodiment, the step of forming one or more inter-pancake connections can include automatically forming one or more other inter-pancake connections.

[0115]

[0133] FIG. 2A is a cross-sectional view of the spiral-grooved plate 205b. The spiral-grooved The plate 205b can be substantially similar to the plate 205a. In this embodiment, the welding lid is not used to enclose the HTS tape stack 250 and the coolant channel 215. The coolant channel 215 is encapsulated by a rectangular coolant tube 240. The rectangular coolant tube can include one or more of copper, copper alloy, or any other material having thermal conductivity characteristics similar to or greater than those of the materials described previously.

[0116]

[0134] In the example illustrated by FIGS. 2 - 2A, the HTS tape stack 250 is oriented perpendicular to the coolant channel 215. This orientation can be selected to increase (and ideally, maximize) heat transfer. Those skilled in the art will understand that other orientations can be used. and preferably, maximized). Those skilled in the art will understand that other orientations can be used.

[0117]

[0135] As mentioned above, FIGS. 3 and 3A illustrate an alternative approach using a shared coolant channel 340 between two oppositely - oriented pancakes 330, 335. In an embodiment, this can be achieved by a coolant channel plate within the stack that is shared between the two oppositely - oriented pancakes 330, 335. In some embodiments, grooves are cut into the surfaces of both oppositely - oriented pancakes 330 and 335 to form the coolant channel (FIG. 3A). FIGS. 3 and 3A are cross - sectional views showing the option of stacking two grooved plates against a shared coolant channel (e.g., by a shared coolant channel plate, or by a conduction - cooled plate, or by cutting matching grooves into the surface of the grooved plate, as well as into the copper lid covering the HTS stack and the co - winding). If desired, copper interconnects between the pancakes can be fabricated within this region. It should be noted that elements similar to those in FIGS. 3 and 3A are given similar reference numerals.

[0118]

[0136] ​​This "coolant channel plate" concept provides significant flexibility for improving (and ideally, optimizing) the coolant path. This can be a useful feature in some applications such as SPARC toroidal field coils. As an alternative, a conduction-cooled plate can be used in place of, or eliminated entirely from, designs and applications that have a low level of internal volume heating.

[0119]

[0137] To control the quench dynamics and to help reduce the temperature rise of the HTS tape during a quench, a conduction plate (e.g., copper) can be inserted between the double pancakes, and one finding is that quench-induced eddy currents will be preferentially induced within these structures, which serves to localize the magnetic energy deposition to regions that are thermally and electrically isolated from the HTS tape. Such structures are, of course, accommodated by the stacked plate design concept with spiral grooves, and those structures can be directly incorporated into the coolant channel plate design that is electrically isolated from the pancakes and in good thermal contact with the coolant. To control the quench dynamics and to help reduce the temperature rise of the HTS tape during a quench, a high electrical conductivity coating (e.g., copper) and / or an insulating coating (e.g., alumina) can be applied to selected regions of the spiral grooved plate, including but not limited to the grooved sides and the non-grooved sides of the plate, and one finding is that the quench-induced current density, distribution, and resulting Joule heating can be controlled by tailoring the resistance of the major electrical paths within the magnet structure.

[0120]

[0138] To control the quench dynamics and to help reduce the temperature rise of the HTS tape during a quench, This stacked plate geometry can, of course, further, as shown in Figure 3A

[0121]

[0139] This stacked plate geometry can, of course, further, as shown in Figure 3A As shown, if desired, it receives the copper interconnects between the pancakes. At the same time, the grooved plate / coolant channel plate assembly can be designed by a suitable selection of materials to maintain a relatively high resistance electrical connection between adjacent pancake windings, which can be used to reduce the magnet charge time in this non-insulated superconducting magnet design.

[0122]

[0140] It may be advantageous to apply a preload to the tape stack in the groove before soldering, or to use a preloading mechanism that eliminates the need for soldering altogether. FIGS. 2 and 5 illustrate the use of a "wedge shim" to accommodate this, although the use of a hydraulic bladder is also possible (FIG. 4) and preferred in many instances.

[0123]

[0123]

[0141] FIG. 3 shows two plates 330, 335 having spiral grooves 320 provided therein is a cross-sectional view. Plates 330, 335 have a shared coolant assembly 340 therebetween, and the assembly can be a coolant channel (such as can be readily made by, for example, providing in a coolant channel plate and / or by cutting grooves in the upper surface of the spiral-grooved plate and in the copper covering the HTS stack and co-winding), or a conduction-cooled plate as described above. The double-pancake structure prepared from the spiral-grooved plates 330, 335 and the coolant assembly 340 can have a width 341 of about 20 mm, but this width is merely illustrative. In the illustrative embodiment of FIG. 3, the spiral groove 320 includes an HTS tape stack 305 with an optional co-winding material and a cover plate 310 that can be composed of copper or other thermally conductive material. In other embodiments, the cover plate 310 can be eliminated such that the HTS stack and co-winding are exposed directly to the coolant or directly to the conduction plate. In this illustrative embodiment, the plate has a length 336 of about 14 mm, the tape and channel 320 are provided with a width 337 of about 4 mm and a length 338 of about 4.5 mm, and one of the channels (here illustrated as channel 320a) is formed or otherwise provided at a distance 339 of about 2.5 mm from the surface of plate 335. However, these dimensions are merely illustrative because the structures described herein can have any of a variety of suitable dimensions.

[0124]

[0142] One embodiment where the coolant assembly 340 is a coolant channel between plates 330, 335 In a configuration, the coolant path established by the channels is not constrained to flow along the HTS stack, and thus can be optimized for heat removal. For example, short radial paths across the HTS stack that more effectively spread heat across the winding can be used. This can be useful for applications where a high level of internal volume heating of the magnet windings can occur (e.g., toroidal field magnets for SPARC). Additionally, multiple coolant annular tubes can be used that reduce the coolant velocity and drive pressure requirements. Ultimately, the coolant passages can have variable sizes and can be realized by diverting more volume into the winding section relative to the structural elements only when those passages are needed. In embodiments with a lower level of internal volume heating, conduction cooling techniques may be appropriate. In this case, the coolant channel plates may be replaced by, or even eliminated by, plates that are conduction cooled.

[0125]

[0143] To control the quench dynamics and to help reduce the temperature rise of the HTS tape stack 305 during a quench, a conduction plate (e.g., copper) can be inserted between plates 330, 335 within the coolant channel region 340. Thus, the quench-induced eddy currents will be preferentially induced within the conduction plate, which localizes the dissipation of the stored magnetic energy to a region that is thermally and electrically isolated from the HTS tape 305.

[0126]

[0144] FIG. 3A is a cross-sectional view of two plates 330, 335 having grooves 320 provided therein It is a figure. Plates 330 and 335 are stacked with respect to a shared coolant assembly 340 that can be a coolant channel plate, a groove in the upper surface of the plate, or a conduction-cooled plate. An interconnect 350 is disposed within the region between plates 330 and 335. This interconnect serves to bridge the current path between the innermost windings of adjacent plates within the magnetic assembly (see 621 in FIG. 6, 621a in FIG. 6A, and 720b in FIG. 6C). In an exemplary embodiment, the interconnect 350 can include copper (e.g., high thermal and electrical conductivity copper) that is soldered to the HTS stack by an interfacial layer (e.g., using an indium or indium alloy interfacial layer) to bridge the connection. Connections soldered at a suitable low melting temperature can further be used. The interconnect 350 combined with the overall electrical connection between plates 3 30 and 335 is configured to receive the bypass current flowing during magnetic charging, while further increasing (and ideally, maximizing) the electrical resistance between plates 330 and 335, which reduces (and ideally, minimizes) the magnet charging time.

[0127]

[0145] FIG. 4 is a cross-sectional view of a magnet 400 including a first plate 430 and a second plate 435 is. An insulator 440 is disposed between plates 430 and 445. In this embodiment, the insulator 440 inhibits (and ideally, prevents) the bypass current generated from magnetic charging from flowing directly across plates 430 and 435. Instead, such current is forced to flow along the plates and propagate (or jump) across the plates only in the vicinity of the interplate interconnect in that embodiment (e.g., interconnect 350 in FIG. 3A) or in the vicinity of the helical HTS tape stack interconnect in that embodiment (e.g., groove 125 in FIG. 1). The insulator can be composed of, but is not limited to, fiberglass composites, mineral insulators (e.g., mica), alumina, or insulating coatings such as alumina.

[0128]

[0146] The spiral groove 420 is provided in the plates 430, 435. The co-wound material is included The obtained HTS tape stack 405 is inserted into the groove 420, and a lid assembly 410 (which can be provided as a copper lid assembly, for example) is disposed on top of the HTS tape stack and the co-wound 405.

[0129]

[0147] The bladder element 415 (or, more simply, the bladder 415) is disposed in the groove (or channel) to compress the stack 405 against the side wall 411. In an embodiment, the bladder 415 can be a hydraulic bladder into which hydraulic fluid can be applied to effect compression. In some embodiments, the bladder 415 is positioned such that the tape stack 405 is compressed against the main load-bearing side wall. In this example, the tape stack is provided with a width 412 of about 4 mm and a length 413 of about 4.5 mm, and the direction of the main load (i.e., the main Lorentz force (IxB) load) in FIG. 4 is designated by reference numeral 416, which consequently indicates that the side wall 411 corresponds to the main load-bearing side wall. The bladder 415 compresses the HTS tape stack 405 such that the impact of the Lorentz force (IxB) load being cyclically applied and released can be reduced (and ideally, minimized). In this illustrative embodiment, one of the channels (here, channel 420a) is formed or otherwise provided at a distance 439 of about 2.5 mm from the surface of the plate 435. However, these dimensions are merely illustrative, because the structures described herein can have any of a variety of suitable dimensions.

[0130]

[0148] In an embodiment, the bladder element is a co-wound element within the HTS tape stack It may be included as part of the HTS tape laminate. The bladder element may be configured within the HTS tape laminate to facilitate the soldering process by applying a preload to the HTS tape laminate prior to soldering so as to fix the HTS tape laminate at a desired position. In an embodiment, the bladder element may further be configured within the HTS tape laminate so as to eliminate the need for soldering. The bladder element may further be configured to pre-compress the HTS tape laminate against the load-bearing sidewalls of at least one spiral groove.

[0131]

[0149] In some examples, after the HTS tape laminate 405 is soldered, the hydraulic fluid can be removed and further replaced by an inert gas. In the case where the bladder 415 is empty, the bladder serves as a spring to accommodate the differential thermal contraction of the soldered HTS laminate 405 relative to the grooved plates 430, 435 during the magnet cooling and warm-up periods, in order to reduce the risk of HTS laminate and co-winding peel damage. works.

[0132]

[0150] In other examples, if the hydraulic fluid is retained, the compressive force on the HTS tape laminate 405 can be maintained such that the laminate is fully immobilized. The hydraulic fluid can be selected such that it freezes at the magnet operating temperature, eliminating the need to actively maintain the hydraulic pressure.

[0133]

[0151] In some cases, the bladder element is liquid during assembly but the magnet operating temperature There may be materials that are solid at a certain temperature and contain (e.g., are filled with that material or, in other forms, have that material disposed therein). One such material includes, but is not limited to, gallium. The heat of fusion associated with this material can act as a large thermal reservoir to limit the temperature rise of the tape laminate 405 during a quench event, i.e., to limit the HTS laminate temperature such that it is below the melting temperature of 29.8 degrees Celsius in the case of gallium.

[0134]

[0152] In all of these embodiments, the selection of materials, coatings, conductors , semiconductors, and insulators in the assembly can be used to improve (and ideally, optimize) the current shunting and eddy current paths in response to a magnet quench event and to safely distribute the magnet quench energy over a large volume.

[0135]

[0153] Similar elements are given similar reference designations. Now refer to FIGS. 5 - 5A Then, shown is a cross-sectional view of a magnet illustrating an example of how the selection of materials, coatings, conductors, semiconductors, and insulators in a co-wound tape stack and a plate with spiral grooves can be used to control the region of magnet quench energy heat-induced quench according to the embodiments described herein. The arrow designated by reference numeral 510 in FIGS. 5 - 5A represents the flow of a current shunt current driven by a quench event. In this example, current is driven from a first (or lower) HTS tape stack 505a to a second HTS stack 505b (here, the closest neighbor 505b of stack 505a). Taking up the configuration of tape stack 505b as illustrative of tape stack 505a, tape stack 505b is disposed within a groove 506 provided within a plate 530. A wedge shim 508 (or alternatively, a blada) is disposed within the groove 506 adjacent to tape stack 505b. A coolant channel 515 defined by a C-shaped member 520 is disposed in thermal contact with tape stack 505b. A lid 525 is disposed above the coolant channel. The wedge shim 508, coolant channel 515, C-shaped member 520, and lid 525 can be the same or similar (both in structure and function) to the wedge shim (or blada), coolant channel, C-shaped member, and lid described hereinabove in connection with FIGS. 2 - 4.

[0136]

[0154] The rate of volumetric heat generation in the plate with spiral grooves due to the quench current is ηj 2It can be quantified, where j is the current shunt current density and η is the electrical resistivity of the material through which the current flows. In FIG. 5A, the insulator 540 is inserted as a co-wound material at the base of the HTS stack, while in FIG. 5, such an insulator does not exist. Since the insulator exists in FIG. 5A, the quench current flows deeper and over a longer distance into the backbone of the grooved plate 530 compared to the embodiment in FIG. 5. Thus, the volume in which the quench energy is dissipated is larger in FIG. 5A compared to FIG. 5. Alternatively or in addition, the non-grooved side portions of the spiral grooved plate can be coated with a high electrical conductivity material (e.g., copper), which promotes the deep flow of the current shunt current into the backbone of the spiral grooved plate, thereby increasing the volume of the material in which the quench energy is dissipated. This can be done.

[0137]

[0155] In overview, FIGS. 6 - 6C show how a spiral grooved, HTS-filled The interleaved stack of the plates to be embedded and the coolant channel plates (improved by coolant channel grooves machined into the surface of the spiral groove plates according to the description) can be illustrated to be assembled to form a high magnetic field magnet. In these illustrations, it should be perceived that options for interconnects between pancakes (such as the copper interconnects described in FIG. 3) are shown. However, it should be understood that the helical tape interconnect options as described above in connection with FIG. 1 can further be used and are preferred in some applications (such as small fusion applications). In one embodiment, a magnet with a radial build of H = 160 mm, a width W = 140 mm, and a clear bore diameter S = 100 mm is expected to produce approximately 20 Tesla axially using existing commercially available HTS tape. The spiral grooved plates can be fabricated by additive manufacturing techniques (such as 3D printing) in superalloys such as Inconel 625 using commercially available methods. The stress in the support plates is expected to be well within acceptable limits for 3D printed parts made from Inconel 625.

[0138]

[0156] FIG. 6 is a cross-sectional view of a high magnetic field coil 600 comprising a stack of six spiral grooved double pancakes 605a - 605f, generally represented as 605, each of the double pancakes being accompanied by coolant channel plates 606a - 606f inserted therebetween or otherwise disposed. As touched upon above, in one embodiment, the high magnetic field coil 600 is expected to achieve approximately 20 Tesla axially using existing commercially available HTS tape according to the embodiments described herein.

[0139]

[0157] In this embodiment, the current passes through the external feed-in section 615 to the top of FIG. 6 ​flows into and out of each double pancake 605 therein. The current wraps around the spiral grooves of each plate and alternately passes through cross-sectional views of 635 and 630. In this case, an internal interconnect (represented generally as 621) is used to connect the electrical path across the innermost winding, spiral winding, similar to the internal connection 350 described above in connection with FIG. 3A. Thus, the pairs of connected spiral grooved plates effectively form six double pancake subassemblies 605a - 605f.

[0140]

[0158] In this embodiment, a feeding portion represented generally as 620 is configured to send and receive coolant into coolant channels 622a - 622f disposed in the middle of the double pancake assembly.

[0141]

[0159] FIG. 6A is a top view of an exemplary magnet assembly 600, the cross-sectional view of which is shown in FIG. 6, of a first spiral grooved plate 705a. The plate 705a can be provided from any conductive material 706 including a metal or alloy. Such materials include, but are not limited to, one or more of nickel-based superalloys such as Inconel 718 and Hastelloy C276, austenitic stainless steels, and dispersion-strengthened copper alloys. Factors influencing material selection include, but are not limited to, mechanical strength, electrical conductivity, thermal conductivity, and coefficient of thermal expansion. In an embodiment, the plate material 706 can include a composite of different materials. The material can be selected to optimize the uniformity of quench energy imparted, structural integrity under load and under off-normal situations, and to minimize cost. As touched upon above, additive manufacturing techniques can be readily used to fabricate the plate geometries used upon which the magnets can be built.

[0142]

[0160] The first plate 705a is configured to receive an HTS tape stack 710a. It includes an inlet 715a. The HTS tape stack 710a is fed into the groove channel (e.g., the groove or channel 130 in FIG. 1) of the first plate 705a. In this embodiment, the first plate 705a includes an electrical interconnect 621a in the innermost winding, similar to 350 illustrated in FIG. 3A. In this case, the electrical interconnect components are in the shape of a circular ring. The first plate 705a is stacked on a second plate (e.g., the second plate 705b in FIG. 6C), and a cooling plate 730 (e.g., the insulating radial coolant channel plate shown in FIG. 6B) is inserted between the two spiral-grooved plates 705a, 705b. Thus, in this exemplary embodiment, the spiral-grooved plates 705a, 705b and the cooling plate 730 form a double-pancake structure.

[0143]

[0161] In some embodiments, the HTS tape and the co-wound stack include locations where the HTS tape and the co-wound stack enter (715a) and exit (715b) channels on each of the spiral-grooved plates and are embedded in copper, or other suitable high electrical conductivity material in a wide area that extends without interruption to the current feed connection on the outside of the spiral-grooved plates. This helps protect the HTS from overheating and damage during magnet charging and magnet quench events.

[0144]

[0162] In some embodiments, two or more HTS tape stacks can be disposed within the grooved channel and separate structures and / or co-wound materials are disposed between the tape stacks, and the dimensions of the channel grooves are appropriately modified to receive these materials and / or to mechanically engage these materials, such as by secondary spiral grooves. In some embodiments, some or all of the co-wound materials can be disposed to mechanically engage the plates, such as by spiral grooves.

[0145]

[0163] The internal electrical interconnect, which perhaps takes the shape of a circular ring in this example case, Furthermore, it should be noted that it may be used on the outermost turns to connect between double pancake assemblies.

[0146]

[0164] If the double pancake embodiment of FIGS. 1-1C is used, as shown here It should be noted that there would be no need to use internal interconnects at the innermost turns. Instead, the HTS tape stack and co-wrap would be continuously connected from spiral groove plate 705a to plate 705c. In this case, the coolant channel plates would be placed beside each double pancake assembly, rather than between the two plates that form the double pancake assembly as depicted here.

[0147]

[0165] FIG. 6B shows a tubular coolant passage 735 having radially insulating coolant channels 735 disposed therein. 7 is a top view of the cooling channel plate 730. The cooling channel plate 730 is configured to receive cooling fluid via the coolant inlet assemblies 745a-N. In this embodiment, four separate flow paths of coolant into and out of the cooling channel plate are depicted by arrows. The cooling channel plate is constructed such that it is electrically isolated from the spiral groove plates 705a and 705b when it is placed in the assembly. This feature prevents bypass currents resulting from magnet charging from flowing through the coolant channel plate between the plates 705a and 705b. This function can be accomplished by fabricating the plate from a non-conductive material, such as, but not limited to, a fiberglass composite; applying an insulating coating to an otherwise conductive base material, or by some other suitable means. In some embodiments, the coolant channel plate forms only the side walls of the coolant channels, with the adjacent HTS stack and spiral groove plate forming the remaining walls. In this case, the coolant is in direct contact with the HTS stack and co-windings. In other embodiments, grooves can be cut into the surfaces of adjacent spiral grooved plates and into the copper lid material to serve as coolant channels. The grooves can extend along or across the HTS stack as needed to facilitate cooling, optimize coolant passage length, and minimize pressure drop.

[0148]

[0166] Please note that the coolant paths shown in FIG. 6B are for illustration only. It should be understood that these paths can be tailored by the needs and constraints in magnet design, such as heat removal and structural integrity considerations of the magnet assembly. The coolant channel plate can be replaced by a conductively cooled plate, or eliminated altogether, replaced by a simple insulating material. In the latter case, the coolant channel passages can be formed by cutting grooves into the surface of the spiral grooved plate and into the copper lid material.

[0149]

[0167] FIG. 6C is a top view of the second spiral grooved plate 705b. 1A )。 In this embodiment, the second plate 705b includes an inlet 715b configured to receive an HTS tape stack 710b. The HTS tape stack 710b is fed into the groove channel (e.g., groove channel 135 of FIG. 1A ) of the second plate 705b. The HTS tape stack 710a is fed into the groove channel (e.g., groove channel 135 of FIG. 1A ) of the second plate 705b. In this embodiment, the second plate 705b includes electrical interconnects 720b that align with and mate with the electrical interconnects 720a of the first plate 715a.

[0150]

[0168] In overview, Figures 7-7D show that the HTS tape stack is directly FIG. 7-7D illustrate an alternative embodiment of a double pancake assembly of stacked plates with spiral grooves wound within some intervals or grooves on the stack itself. FIGS. 7-7D further illustrate a portion of the periphery of the outer diameter of the coil and a conductive terminal block spanning the entire periphery of the inner diameter of the coil. In some embodiments, the inner and outer conductive terminal blocks span only a portion of their respective peripheries or the entire periphery of the coil. In embodiments, the conductive terminal block is provided as a copper terminal block, although any material having a suitable electrical conductivity may be used. The plates with spiral grooves can be fabricated by the techniques described above. In the embodiments of FIGS. 7-7D, the HTS stack may include a co-wound material as described above, and it is appreciated that the thickness and composition of the stack can be varied along the length of the stack to optimize for current density, magnetic field concentration, and quench behavior.

[0151]

[0169] It is appreciated that the use of variable-width spiral grooves has several advantages. By varying the width of the grooves, the HTS stack (and co-winding) can be wound directly onto itself a given number of times within each radial groove. Doing so allows for precise control over the current density distribution within the winding, which can be used to reduce magnetic field strength variations and concentrations within the HTS tape due to self-fields. Under the assumption that the magnetic field will decrease in magnitude with increasing distance from the center of the assembly 800, it is appreciated that the HTS stack can withstand a larger number of self-winds within each groove with increasing radial distance from the center of the assembly.

[0152]

[0170] Moreover, the use of variable-width spiral grooves is for the entire length of the HTS tape stack This eliminates the need to cut (or otherwise form or provide) "thin grooves" in the plate. For purposes of this disclosure, a groove is considered "thin" when its depth is more than twice its width. Thus, using plates with variable width spiral grooves provided therein allows for the production of thin HTS tape stacks without the need for using thin grooves. The design further allows the coil and its structure to be separately optimized with respect to magnetic field generation, self-field experienced by the HTS tape, and mechanical loading, i.e., structural stiffness, location for welds and fasteners, location for coolant channels including channels between plates.

[0153]

[0171] Similar elements are given similar reference designations throughout the several views. 7-7D, in which a variable width spiral grooved stacked plate double pancake magnet assembly 800 includes a plate 802 and disposed within the plate is a conductive (e.g., copper) terminal block 804 and an HTS tape stack 806 that is contained within several grooves of varying widths and wound on itself to occupy (and ideally completely occupy - i.e., "fill") the space of each such groove. In particular, magnet assembly 800 includes walls 810, 812, 814, 816, and 818 that define various grooves that are filled by HTS stack 806 (and any co-windings). Magnet assembly 800 further includes a second optional copper terminal block 820 along an inner diameter of the assembly. The magnet assembly 800 further includes an outer structural member 822 and an inner structural member 824, which may be made from the same material as the stacked plates 802.

[0154]

[0172] Grooves in a Double Pancake Magnet Assembly of Stacked Plates with Variable Width Spiral Grooves It is appreciated that the number of HTS tape stacks (and therefore the number of walls) may vary depending on the intended use. It is further appreciated that the number of HTS tape stacks and / or co-wound turns in each groove may likewise vary depending on the intended use. Thus, Figure 7 is merely illustrative, and after reading the description provided herein, those of ordinary skill in the art will appreciate how to adapt the concepts, techniques, and structures described herein to form other embodiments.

[0155]

[0173] Each of the walls 810, 812, 814, 816, and 818 has the same structure as described above. 8. The magnetic tape stack 806 may include cooling means such as those described above, and / or may provide structural support for the magnetic forces experienced by the HTS tape stack 806.

[0156]

[0174] Each of the walls 810, 812, 814, 816, and 818 is connected to a magnet assembly 80. 7D , some (or even all) of the walls have varying (i.e., tapering) thicknesses at different angular positions (see, e.g., wall 818, including wall portions 818a, 818b). Thus, the same continuous wall may appear to have several portions of varying wall thickness at any given cross-section.

[0157]

[0175] The overall width of a given wall along a given cross section is the total width of that wall as it appears in the cross section. This overall width may be calculated as the sum of the radial extents of each of the portions. This overall width may or may not be equal for different walls in different embodiments, and the overall width of a given wall may vary as a function of the angular position of the respective cross-section.

[0158]

[0176] 7A-7C are diagrams showing the magnet assembly 800 of FIG. 7 along lines AA, BB, and a cross-sectional view taken along C-C, while FIG. 7D shows a perspective view of a portion of the magnet assembly 800.

[0159]

[0177] Referring now to FIG. 7A, the plate 802 is shown with the outer diameter of the magnet assembly 800 at the lower left side (adjacent reference number 822), and the inner diameter of the magnet assembly 800 at the upper right side (adjacent reference number 824). The copper terminal block 804 is shown at the lower left enclosing a portion 806a of the HTS tape laminate 806 on two sides. The third inner surface side of the tape laminate portion 806a abuts the wall 810, while the fourth side of the tape laminate portion 806a may abut another spiral-grooved magnet assembly (not shown) stacked with respect to that fourth side according to the concepts, techniques, and structures disclosed herein. of the magnet assembly 800 at the lower left side (adjacent reference number 822), and the inner diameter of the magnet assembly 800 at the upper right side (adjacent reference number 824). The copper terminal block 804 is shown at the lower left enclosing a portion 806a of the HTS tape laminate 806 on two sides. The third inner surface side of the tape laminate portion 806a abuts the wall 810, while the fourth side of the tape laminate portion 806a may abut another spiral-grooved magnet assembly (not shown) stacked with respect to that fourth side according to the concepts, techniques, and structures disclosed herein. Referring now to FIGS. 7 and 7A, in an individual cross-section A-A of the magnet assembly 800, four layers of the HTS tape laminate 806 are defined by the wall 810 and a portion 812a of the wall 812, and are wound within the grooves running between those walls 810 and portion 812a with respect to themselves. Two such layers 806b and 806c of the HTS tape laminate 806 are shown in FIG. 7A. It is perceived that layering the HTS tape laminate 806 on itself (e.g., in the form of layers 806b and 806c) can advantageously distribute the self-magnetic field strength within the magnet assembly 800 as desired by individual applications.

[0160]

[0178] Referring to FIGS. 7 and 7A, in an individual cross-section A-A of the magnet assembly 800, four layers of the HTS tape laminate 806 are defined by the wall 810 and a portion 812a of the wall 812, and are wound within the grooves running between those walls 810 and portion 812a with respect to themselves. Two such layers 806b and 806c of the HTS tape laminate 806 are shown in FIG. 7A. It is perceived that layering the HTS tape laminate 806 on itself (e.g., in the form of layers 806b and 806c) can advantageously distribute the self-magnetic field strength within the magnet assembly 800 as desired by individual applications. Referring to FIGS. 7 and 7A, in an individual cross-section A-A of the magnet assembly 800, four layers of the HTS tape laminate 806 are defined by the wall 810 and a portion 812a of the wall 812, and are wound within the grooves running between those walls 810 and portion 812a with respect to themselves. Two such layers 806b and 806c of the HTS tape laminate 806 are shown in FIG. 7A. It is perceived that layering the HTS tape laminate 806 on itself (e.g., in the form of layers 806b and 806c) can advantageously distribute the self-magnetic field strength within the magnet assembly 800 as desired by individual applications.

[0161]

[0179] The layers of the HTS tape laminate 806 are with a portion 812a and a portion 81 of the wall 812 2b. As noted above, wall 812 wraps around magnet assembly 800 two or more times, such that two portions 812a and 812b of the wall appear at separate cross sections AA. A channel between these portions 812a and 812b is provided to permit adjacent winding of a single HTS tape stack 806 between the larger groove defined by walls 810 and 812a and the larger groove defined by walls 812b and 814a. Thus, it is seen that an embodiment of magnet assembly 800 may include a single thin stack and still permit high inductance windings.

[0162]

[0180] According to the pattern described above, a portion 812b of the wall 812 is HT 8. The six layers of the stack are wound relative to one another in a groove defined by the portion 812b and a portion 814a of the wall 814. A channel is provided between the portion 814a and a portion 814b of the same wall 814, through which a layer of the HTS tape stack 806 emerges on the other side of the wall 814 as layer 806e. The three layers of the stack are wound relative to one another in a groove defined by the portion 814b of the wall 814 and a portion 816a of the wall 816. A channel is provided between the portion 816a and a portion 816b of the same wall 816, through which a layer of the HTS tape stack 806 emerges on the other side of the wall 816 as layer 806f. The three layers of the stack are wound relative to one another within a groove defined by a portion 816b of wall 816 and a portion 818a of wall 818. A channel is provided between portion 818a and a portion 818b of the same wall 818, and wound through the channel is a layer of HTS tape stack 806.

[0163]

[0181] The innermost portion of the magnet assembly 800, as shown in FIG. It can be occupied by a second optional copper terminal block 820. This non-superconducting terminal block 820 can be used, in some embodiments, to transfer current from (or into) the superconducting HTS tape stack 806. Note that the terminal block 820 can extend completely through the plate 802 to provide an external point of electrical contact. Alternatively, the HTS tape stack 806 can continue its winding from the innermost layer 806g into the adjacent stacked magnet assembly, according to the concepts, techniques, and structures described above. It is appreciated that other configurations of the space between the inner wall (e.g., wall 818) and the inner diameter (e.g., member 824) can be used in various embodiments.

[0164]

[0182] Figure 7B is a cross-section of Figure 7 taken along line B-B, showing a similar pattern with the outer diameter of the magnet assembly 80 0 on the left, and the inner diameter on the right. Thus, as described above, the outer member 822 is shown, then the terminal block 804 above the plate 802, and then the layer 806a of the HTS tape stack 806 that wraps through the channel between the terminal block 804 and the wall 810. Next shown are four layers of the stack in the groove between the wall 810 and the outer portion 812a of the wall 812, and then the layer of the stack in the channel between the portions 812a and 812b of the wall 812.

[0165]

[0183] Of particular note is that the portion 812a, as shown in Figure 7B, is in Figure 7A It is thicker radially than the corresponding portion 812a of the same wall 812 as shown in [figure number]. Thus, the difference between the cross-sections of these figures illustrates how the wall 812 has a varying thickness in different angular directions in the magnet assemblies 800, and in particular, illustrates the tapered shape of the wall 812. Conversely, a portion 812b as shown in FIG. 7B is thinner radially than the corresponding portion 812b of the same wall 812 as shown in FIG. 7A. However, the sum of the radial thicknesses of portions 812a and 812b - that is, the "overall thickness" of the wall 812 along this cross-section - is the same in both figures and does not vary with the angular direction of the cross-section.

[0166]

[0184] Having an invariant overall thickness can be advantageous in some embodiments such that, for example, to the extent that each of portions 812a and 812b provides some structural support for the magnetic force to be redirected, this structural support is uniform and does not vary with the angular direction. However, as explained above, in some embodiments, the overall thickness of the wall 812 can vary with the angular direction. Moreover, in some embodiments, the width of the tape stack can vary with the distance along the stack, which requires that the wall thickness be adjusted accordingly.

[0167]

[0185] Continuing radially inwards with respect to the description of FIG. 7B, a portion 81 of the wall 812 2b is in contact with the boundary of layer 806d of the HTS tape laminate 806. Six layers of the laminate are wound relative to each other within a groove defined by a portion 812b and a portion 814a of the wall 814. A channel is provided between a portion 814a and a portion 814b of the same wall 814, and the layer of the HTS tape laminate 806 that appears on the other side of the wall 814 as layer 806e is wound through that channel. It should be noted that, for the reasons exactly described above, portion 814a is thicker in FIG. 7B than in FIG. 7A, while portion 814b is thinner in FIG. 7B than in FIG. 7A, but the combined thickness of these portions is the same.

[0168]

[0186] Three layers of the laminate are wound relative to each other within a groove defined by a portion 814b of the wall 814 and a portion 816a of the wall 816. A channel is provided between a portion 816a and a portion 816b of the same wall 816, and the layer of the HTS tape laminate 806 that appears on the other side of the wall 816 as layer 806f is wound through that channel. Portion 816a is thicker in FIG. 7B than in FIG. 7A, while portion 816b is thinner in FIG. 7B than in FIG. 7A, but the combined thickness of these portions is the same.

[0169]

[0187] Three layers of the laminate are wound relative to each other within a groove defined by a portion 816b of the wall 816 and a portion 818a of the wall 818. A channel is provided between a portion 818a and the copper terminal block 820, and the layer of the HTS tape laminate 806 is wound through that channel. It should be noted that the terminal block 820 can extend completely through the plate 802 to provide an external point of electrical contact. Further note should be taken that the wall 818 encloses only a single portion 818a in the cross-section B - B illustrated in FIG. 7B. Finally, the material 824 appears along the innermost diameter of the magnet assembly 800. Inner diameter.

[0170]

[0188] Figure 7C is a cross-section of FIG. 7 along line C-C, showing the magnet assembly 8 at the top with an outer diameter of 00 and a similar pattern with an inner diameter at the bottom. Thus, the outer member 822 is shown, and then a portion 810a of the wall 810 is shown. Note that the terminal block 804 does not exist in this cross-section for reasons discussed below. Next, the layer 806a of the HTS tape laminate 806 wraps through the channel between the portion 810a and a portion 810b of the same wall 810.

[0171]

[0189] Next shown are four layers of the HTS tape laminate 806 in the groove between the wall 810 and an outer portion 812a of the wall 812, including the layers 806b and 806c. Shown below that are the layers of the laminate in the channel between portions 812a and 812b of the wall 812.

[0172]

[0190] Note that a portion 812a as shown in FIG. 7C is radially thicker than the corresponding portion 812a of the same wall 812 as shown in FIGS. 7A and 7B. Thus, the difference between the cross-sections of these figures illustrates how the wall 812 has varying thicknesses at different angular directions in the magnet assemblies 800, and in particular, illustrates the tapered shape of the wall 812. Conversely, a portion 812b as shown in FIG. 7C is radially thinner than the corresponding portion 812b of the same wall 812 as shown in FIGS. 7A and 7B. However, the overall thickness of the wall 812 along the cross-section C-C is the same in all three figures and does not vary with the angular direction of the cross-section.

[0173]

[0191] Continuing radially inward (i.e., downward) with respect to the description of FIG. 7C , a portion 812b of the wall 812 is in border contact with the layer 806d of the HTS tape laminate 806. Six layers of the laminate are wound relative to each other within a groove defined by the portion 812b and a portion 814a of the wall 814. A channel is provided between the portion 814a and a portion 814b of the same wall 814, and the layer of the HTS tape laminate 806 that appears on the other side of the wall 814 as the layer 806e is wound through that channel. Again, it should be noted that, as described above, the portion 814a is thicker in FIGS. 7A and 7B, while the portion 814b is thinner in FIGS. 7A and 7B, but the combined thickness of these portions is the same.

[0174]

[0192] Three layers of the laminate are wound relative to each other within a groove defined by a portion 814b of the wall 814 and a portion 816a of the wall 816. A channel is provided between the portion 816a and a portion 816b of the same wall 816, and the layer of the HTS tape laminate 806 that appears on the other side of the wall 816 as the layer 806f is wound through that channel. The portion 816a is thicker in FIG. 7C than in FIGS. 7A and 7B, while the portion 816b is thinner in FIG. 7C than in FIGS. 7A and 7B, but the combined thickness of these portions is the same.

[0175]

[0193] Three layers of the laminate are wound relative to each other within a groove defined by a portion 816b of the wall 816 and a portion 818a of the wall 818. An interference channel is provided between the portion 818a (by the material removed from the copper terminal block 820) and the copper terminal block 820, and the layer of the HTS tape laminate 806 is wound through that channel. It should be noted that the terminal block 820 can extend completely through the plate 802 to provide an external point of electrical contact. Further note that the wall 818 encloses only a single portion 818a in the cross-section C-C illustrated in FIG. 7C. Finally, the material 824 appears along the innermost diameter of the magnet assembly 800.

[0176]

[0194] The inlaid conductive strip or plate 804 includes, among other things, a conductive terminal and a backing. This provides a large contact area between the relatively low conductivity material that comprises the plate 802 and between the HTS tape stack 806 and the conductive terminals. In an embodiment, the conductive terminals are provided as copper terminals and the inlaid conductive strips 804 are provided as inlaid copper strips 804. The use of such conductive strips facilitates achieving low joint resistance between the HTS stack tape 806 and the copper terminals.

[0177]

[0195] This feature occurs when the magnet is being charged and during unusual events. It may be useful to have the contact area be large enough to ensure that the current density at the interface between the copper and backplate material 802 is within acceptable limits (e.g., acceptable Joule heating), both for the materials themselves and for the contact resistance between the materials. This includes design considerations of potential damage from overheating during out-of-the-ordinary events, as well as consideration of the Joule heating distribution within the backplate 802 during charging and the impact of that Joule heating distribution on cooling requirements.

[0178]

[0196] Copper plate 804 is an additional plate for receiving the stack and distributing localized heating effects along it. 7A, portion 806a contacts copper plate 804 along two of its sides, and in FIG.

[0179]

[0197] Various embodiments of the concepts disclosed herein are illustrated in the accompanying drawings. It should be understood that the following description is made with reference thereto. Alternative embodiments may be devised without departing from the scope of the broad concepts described herein. It is noted that various connections and positional relationships (e.g., above, below, adjacent, etc.) will be discussed between elements in the following description and in the drawings. These connections and / or positional relationships can be direct or indirect unless otherwise specified, and the present invention is not intended to be limiting in this regard. Thus, a physical connection can refer to either a direct connection or an indirect connection, and the positional relationship between entities can be a direct positional relationship or an indirect positional relationship. An example of an indirect positional relationship is that a reference in this description to disposing layer or element "A" above layer or element "B" includes the situation where one or more intermediate layers or elements (e.g., layer or element "C") are between layer / element "A" and layer / element "B", provided that the important characteristics and functionality of layer / element "A" and layer / element "B" are not substantially changed by the intermediate layer.

[0180]

[0198] The following definitions and abbreviations will be used for the interpretation of the claims and this specification. As used herein, the terms "comprises (third-person singular present tense)", "comprising (present participle)", "includes (third-person singular present tense)", "including (present participle)", "has (third-person singular present tense)", "having (present participle)", "contains (third-person singular present tense)", or "containing (present participle)", or any other variations thereof, are intended to be non-exclusive inclusions. For example, a composition, mixture, process, method, article, or apparatus that comprises the recited elements is not necessarily limited to only those elements, but can include other elements not expressly recited or inherent to such composition, mixture, process, method, article, or apparatus.

[0181]

[0199] In addition, the term "exemplary" means "serving as an example, instance, or illustration". Any embodiment or design described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments or designs. The terms "one or more" and "one or more" are used herein to refer to any embodiment or design. The term "or a plurality" is understood to include any integer number greater than or equal to 1, i.e., 1, 2, 3, 4, etc. The term "plurality" is understood to include any integer number greater than or equal to 2, i.e., 2, 3, 4, 5, etc. The term "connected" can include indirect "connected" and direct "connected."

[0182]

[0200] The present disclosure relates to "one embodiment," "one embodiment," "example embodiment," etc. References in the specification imply that the described embodiment may include a particular feature, structure, or characteristic, but that any and all embodiments may include that particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described as being related to one embodiment, it is submitted that it is within the knowledge of one of ordinary skill in the art to preferentially use such feature, structure, or characteristic as being related to other embodiments, whether or not expressly described.

[0183]

[0201] For purposes of the description provided herein, the terms "upper," "lower," The terms "right", "left", "vertical", "horizontal", "upper", "lower", and their derivatives shall relate to the structures and methods described as being oriented in the figures of the drawings. The terms "above", "at the top", "on top of", "positioned above", or "positioned at the top" mean that a first element, such as a first structure, is present on a second element, such as a second structure, where intervening elements, such as interfacial structures, can be present between the first and second elements. The term "direct contact" means that a first element, such as a first structure, and a second element, such as a second structure, are connected at the interface of the two elements without any intermediate conductive, insulating, or semiconductor layer.

[0184]

[0202] Those skilled in the art will realize that the concepts, structures, devices, and techniques described herein can be implemented in other specific forms without departing from their spirit, or from their essential concepts or characteristics. The foregoing embodiments are, therefore, to be considered illustrative rather than restrictive of the broad concepts sought to be protected in all respects. The scope of the concept is thus indicated rather by the appended claims than by the foregoing description, and all changes that come within the meaning and range of equivalency of the claims are, therefore, intended to be embraced therein.

Claims

1. a first conductive plate having a first groove; a first high temperature superconductor (HTS) tape stack disposed within the first groove, the first HTS tape stack having a first plurality of turns; a second conductive plate having a second groove; a second HTS tape stack disposed in the second groove, the second HTS tape stack having a second plurality of turns; a conductive connection between the first HTS tape stack and the second HTS tape stack; at least one coolant channel cut into a surface of the first conductive plate and / or the second conductive plate; An apparatus comprising:

2. 10. The apparatus of claim 1, further comprising an insulator for electrically insulating the first conductive plate from the second conductive plate.

3. 2. The apparatus of claim 1, wherein the conductive connection is formed between an innermost turn of the first HTS tape stack and an innermost turn of the second HTS tape stack.

4. 2. The apparatus of claim 1, wherein the conductive connection is formed between an outermost turn of the first HTS tape stack and an outermost turn of the second HTS tape stack.

5. The apparatus of claim 1 , wherein the conductive connections comprise a metal that is not a superconductor at temperatures above 30 Kelvin.

6. The apparatus of claim 5 , wherein the metal comprises copper.

7. The apparatus of claim 6 , wherein the first conductive plate provides an electrical connection between each turn of the first plurality of turns.

8. The apparatus of claim 1 , wherein the first conductive plate comprises a metal or a metal alloy.

9. The apparatus of claim 8 , wherein the first conductive plate comprises steel.

10. The apparatus of claim 1 , wherein the first HTS tape stack comprises rare earth barium copper oxide.

11. 2. The apparatus of claim 1, wherein the first groove includes at least first and second turns, the first turn having a first width and the second turn having a second width, the second width being greater than the first width.

12. 12. The apparatus of claim 11, wherein the second turn of the first groove comprises a plurality of turns of the first HTS tape stack.

13. a first conductive plate having a first groove; a first high temperature superconductor (HTS) tape stack disposed within the first groove, the first HTS tape stack having a first plurality of turns; a second conductive plate having a second groove; a second HTS tape stack disposed in the second groove, the second HTS tape stack having a second plurality of turns; a conductive connection between the first HTS tape stack and the second HTS tape stack; at least one coolant channel cut into a surface of the first conductive plate and / or the second conductive plate; Equipped with the first conductive plate providing an electrical connection between each turn of the first plurality of turns; the second conductive plate providing an electrical connection between each turn of the second plurality of turns. magnet.

14. 14. The apparatus of claim 13, further comprising an insulator for electrically insulating the first conductive plate from the second conductive plate.

15. forming a first conductive plate having a first groove; disposing a first high temperature superconductor (HTS) tape stack into the first groove; forming a second conductive plate having a second groove; disposing a second HTS tape stack into the second groove; forming at least one coolant channel within a surface of the first conductive plate and / or the second conductive plate; electrically connecting the first HTS tape stack and the second HTS tape stack; A manufacturing method including:

16. The method of claim 15 , wherein forming the at least one coolant channel comprises cutting at least one coolant channel into the surface.

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