JP2001044523A - Persistent current switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent insulation between a supercoductor and a heater from being destroyed, even if a high voltage is applied due to quenching of the superconducting coil. SOLUTION: A switching element 2 has a heat-insulating frame part 3 and a superconductor winding-in part 4 formed by winding a superconductor near the center part inside the frame part. A heater 5 for heating is arranged between the frame parts 3 of adjacent switching elements 2 by being adhered with thermoplastic resin 7 or epoxy-based resin with which a filler of calcium silicate is mixed in. Since a frame part 3, which functions as an insulating member, is interposed between the heater 5 and superconductor winding-in part 4 to separate both, sufficient withstand voltage is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a permanent current switch mainly used for a superconducting magnet device of a magnetic levitation train or the like.

[0002]

2. Description of the Related Art A superconducting magnet used in a magnetic levitation train or the like is used in a permanent current mode in which a constant current flows for a long time. The permanent current mode is a state in which the electric circuit of the superconducting magnet is closed in a closed loop so that the current is confined.In the permanent current mode, the current of the closed loop electric circuit continues to flow semi-permanently without attenuating, The superconducting magnet is in a state capable of maintaining a constant magnetic field. The permanent current switch is a switch for turning on and off such a permanent current mode. In the field of a magnetic levitation train, a thermal permanent current switch for turning on and off the permanent current mode by controlling the energization of a built-in heater is widely used. .

FIG. 18 is an electric circuit diagram for explaining a process of creating a permanent current mode by using such a thermal permanent current switch. First, the heater H inside the permanent current switch PCS is energized from the heater power supply P0, the temperature of the permanent current switch PCS is raised, and the current I of the power supply P is increased in an open state (OFF (normal conduction state)). (Figure 1
8 (a)). When the current reaches the set current I0,
The energization heating of the heater H of the permanent current switch PCS is stopped,
The permanent current switch PCS is closed [ON (superconducting state)] (FIG. 18B). Here, when the current of the power supply P is gradually reduced, the current I0 flowing into the superconducting coil C is reduced.
Is the difference I0 from the current I flowing to the power supply P while maintaining the set value.
Only −I flows to the persistent current switch PCS (FIG. 1).
8 (c)). Further, even after the current of the power supply P is reduced to zero, the permanent current I0 continues to circulate in the closed loop of the superconducting coil C and the permanent current switch PCS, and the mode becomes the permanent current mode (FIG. 18D). Although not shown in the electric circuit diagram of FIG. 18, actually, the superconducting coil C or the permanent current switch PCS is quenched (the superconducting state suddenly changes to the normal conducting state due to disturbance or the like). ) Is provided with a protection resistor for preventing the circuit from burning when an abnormality such as) occurs.

[0004] Next, the environment in which the thermal permanent current switch as described above is arranged, the structure of the thermal permanent current switch, and the like will be sequentially described. FIG. 19 is a cross-sectional view showing a schematic configuration of a magnetic levitation train. In this figure, a magnetic levitation train 51 has a guideway 5 having a substantially U-shaped cross section.
2 and has a vehicle body 53 and a bogie 54 to which wheels 55 are attached. A superconducting magnet device 56 for cooling a superconducting coil 57 is disposed on the side of the carriage 54, and a cooling device 58 is attached to the superconducting magnet device 56. A propulsion coil 59 is attached to the inner side surface of the guideway 52, and the magnetic levitation train 51 obtains propulsion by electromagnetic force generated between the propulsion coil 59 and the superconducting coil 57.

FIG. 20 is a perspective view showing the configuration of the superconducting magnet device 56 and the cooling device 58 in FIG. In this figure, a cooling device 58 installed above a superconducting magnet device 56 has a refrigerator 60 and a coolant tank 61. The superconducting magnet device 56 has an outer tank 62, a heat shield plate 63 disposed inside the outer tank 62, and an inner tank 64 disposed further inside the heat shield plate 63. are doing. This heat shield plate 63 and inner tank 6
4 is supported by the outer tank 62 by a load supporting member 65. A permanent current switch 66 is provided near the center of the outer tub 62.

FIG. 21 is a view taken in the direction of arrows AA in FIG. As shown in the figure, a superconducting wire is wound inside the inner tank 64 to form a superconducting coil 57.

FIG. 22 is a view taken in the direction of arrows BB in FIG. As shown in this figure, the permanent current switch 66 is provided in a switch inner tank container 67. The lead portion 68 of the permanent current switch 66 is connected to the superconducting coil 57
And the lead 69 of the superconducting coil 57 is connected to a power source (not shown).

FIG. 23 is a perspective view showing the external structure of the permanent current switch 66 shown in FIGS. As shown in this figure, the permanent current switch 66 is configured by joining a plurality of plate-like switch elements 70,
The switch elements 70 are electrically connected in parallel by the lead portions 68. Here, when the number of the switch elements 70 is N and the energizing current is I0, M disturbances (usually, the value of M is set to M = 1 or 2) quench the M switch elements 70 due to some disturbance. Also, the current I0 is shared by the remaining NM switch elements 70 so that the permanent current mode can be maintained.

FIG. 24 is a perspective view showing an external configuration of a permanent current switch 71 of a type different from the above-described permanent current switch 66. As shown in this figure, the permanent current switch 71 has a plurality of substantially cylindrical switch elements 72, and these switch elements 72 are electrically connected in parallel by a lead portion 73. Both ends of the plurality of switch elements 72 are attached to the holding plate 74.

FIG. 25 is a partially broken sectional view showing the internal structure of the permanent current switch 66 shown in FIG. As shown in this figure, a plurality of switch elements 70 are joined via fixing flanges 75. Each switch element 70
Are a frame portion 76 formed of a material such as FRP or GFRP, a superconducting wire winding portion 77 disposed in the frame portion 76, and a heating portion disposed near the center of the superconducting wire winding portion 77. And a heater 78. FIG. 25
Although not shown in the figure, in actuality, a superconducting wire winding portion 77 and a heating heater 78 of the same shape and the same material as the switch element 70 are provided outside the switch elements 70 at both ends. A flat presser plate that is not disposed on the lower plate is attached.

FIG. 26 is a partially broken sectional view showing the internal structure of the permanent current switch 71 shown in FIG. As shown in this figure, each switch element 72 is FRP or G
A frame portion 79 formed of a material such as FRP, a superconducting wire winding portion 80 disposed in the frame portion 79, and a heating portion disposed on the inner and outer peripheral sides of the superconducting wire winding portion 80. And a heater 81.

[0012]

In the case of a superconducting magnet device used in a floating railway, if a quench occurs in a superconducting coil or a permanent current switch, the current is rapidly attenuated and the magnetic field of the quenched superconducting coil disappears. Therefore, from the viewpoint of running safety, the permanent current switch of the superconducting coil on the opposite side is turned off (by turning on the heater) so that the permanent current mode is quickly changed so as not to lose the electromagnetic force balance between the right and left sides of the vehicle. The system to cancel.

In this case, at both ends of the quench-side superconducting coil, a high voltage (as much as about 1 kV) determined by the inductance and the protection resistance of the coil is generated for several seconds, and therefore, both ends of the permanent current switch connected to this are connected. A similar high voltage is generated at the same time. In the opposed-side superconducting coil 57, generation of such a high voltage can be prevented by slowing the turning-off speed of energizing the heater of the permanent current switch to some extent.

Looking at the structure of the permanent current switch, for example, in FIG. 25, the heater 78 is disposed near the center of the superconducting wire winding portion 77, and forms the superconducting wire winding portion 77. Each superconducting wire is a heater 7
8 is located very close to it. The individual superconducting wires are coated with an insulating material such as PVF (polyvinylformal), and the heating heater 78 is also coated with a heat-resistant insulating material such as polyimide. When a high voltage is generated due to the quench, the insulation between them may be broken. In particular, the superconducting wire winding portion 77 is formed through a process of solidifying and fixing individual superconducting wires by impregnation with a resin such as epoxy, and during this process, the space between the superconducting wire and the heater 78 is heated. In some cases, bubbles called "voids" may be generated. When such a void exists, the possibility that the insulation between the superconducting wire and the heater 78 is destroyed becomes higher.

The present invention has been made in view of the above circumstances, and reliably prevents insulation between a superconducting wire and a heater from being broken even when a high voltage is applied due to quench of a superconducting coil. It is intended to provide a permanent current switch capable of performing such operations.

[0016]

As a means for solving the above-mentioned problems, the present invention according to the first aspect of the present invention relates to a superconducting wire winding portion formed by winding a superconducting wire inside an insulating frame portion. A plurality of switch elements, and the plurality of switch elements are electrically connected in parallel in a state of being immersed in a coolant, and the heating heater is disposed near the superconducting wire winding portion. In the thermal permanent current switch for controlling the generation resistance of the superconducting wire by performing a transition between the superconducting state and the normal conducting state of the superconducting wire by performing energization control with respect to the superconducting wire, The heating heater is disposed separately from the superconducting wire winding portion with an insulating member interposed therebetween.

According to a second aspect of the present invention, in the first aspect of the present invention, the plurality of switch elements are joined to each other in a state where the respective flat heat-insulating frame portions are overlapped in the thickness direction thereof. Wherein the heater for heating is disposed between the flat heat-insulating frame portions of adjacent switch elements.

According to a third aspect of the present invention, in the second aspect of the present invention, the plurality of switch elements are constituted by a combination of a plurality of switch element pairs each constituted by a pair of switch elements adjacent to each other. The heating heater is disposed between the joining surfaces of the flat heat-insulating frame portions of the switch elements constituting the switch element pair.

According to a fourth aspect of the present invention, in the third aspect of the invention, the thickness of the flat heat-insulating frame portion on the joining surface side is formed smaller than the thickness on the opposite side. And

According to a fifth aspect of the present invention, in the first aspect of the present invention, the plurality of switch elements are joined in a state where respective flat heat insulating frames are overlapped in a thickness direction thereof. A pair of superconducting wire winding portions are disposed inside the flat heat-insulating frame portion of the switch element, and the heating heater is provided in a groove formed between the pair of superconducting wire winding portions. Is disposed.

According to a sixth aspect of the present invention, in the first aspect of the present invention, the plurality of switch elements are joined in a state where the respective flat heat insulating frames are overlapped in the thickness direction. Wherein the heater for heating is:
Inside the flat heat-insulating frame portion of each switch element, and disposed outside or inside the superconducting wire winding portion in the radial direction of the flat heat-insulating frame portion. I do.

According to a seventh aspect of the present invention, in the first aspect of the present invention, each of the plurality of switch elements has a cylindrical heat-insulating frame portion, and the plurality of cylindrical heat-insulating frame portions have a cylindrical shape. Each end face is arranged in a bundled state so as to be located on substantially the same plane, and the heating heater is provided on the inner peripheral surface or the outer peripheral surface of the cylindrical heat-insulating frame portion of each switch element. It is characterized by being provided.

According to an eighth aspect of the present invention, in the first aspect of the present invention, each of the plurality of switch elements has a cylindrical heat-insulating frame portion, and the plurality of cylindrical heat-insulating frame portions have a cylindrical shape. The heating heaters are arranged inside the cylindrical heat-insulating frame portion of each switch element and are wound around the superconducting wire. It is provided inside or outside the part.

According to a ninth aspect of the present invention, in the invention according to any one of the first to eighth aspects, the heating heater comprises:
The heating heater is a thermoplastic resin containing a copolymer of ethylene and methacrylic acid as a main component, or is bonded to the heat insulating frame portion by an epoxy resin mixed with a filler such as calcium silicate, It is characterized by.

The invention described in claim 10 is the invention according to claims 1 to 9
The invention according to any one of the above, wherein a good heat conductive insulating member is disposed between the heating heater and the superconducting wire winding portion.

According to an eleventh aspect of the present invention, in the tenth aspect of the present invention, the good heat conductive insulating member is disposed in a spot form between the heating heater and the superconducting wire winding portion. Is characterized in that:

The twelfth aspect of the present invention is the first aspect of the present invention.
In the invention according to any one of the first to third aspects, in the heating heater, the direction of current in a certain resistor portion is opposite to the direction of current in another resistor portion disposed along the resistor portion. Thus, a non-inductive circuit for canceling a magnetic field is formed.

According to a thirteenth aspect of the present invention, in the twelfth aspect of the invention, the heating heater has a folded portion formed between the certain resistor portion and the other resistor portion. It is characterized by the following.

According to a fourteenth aspect of the present invention, in the twelfth aspect of the present invention, the heater is provided with a common connection portion for connecting the certain resistor portion and the other resistor portion. The portion is not formed.

[0030] The invention according to claim 15 is the invention according to claims 1 to 1.
5. The invention according to claim 4, wherein a distance between the superconducting wire outlet of the switch element and a heater terminal of the heater is at least 10 mm or more.

[0031]

FIG. 1 is a structural view of a permanent current switch 1 according to a first embodiment of the present invention. FIG. 1A is a perspective view showing the appearance and internal structure of the permanent current switch 1.
FIG. 2B is a partially enlarged cross-sectional view showing the vicinity of the “A” part in FIG. As shown in FIG. 1A, a permanent current switch 1 includes a plurality of switch elements 2 having a flat plate shape.
Are joined in a state of being overlapped in the thickness direction. The switch element 2 includes a heat insulating frame portion (for example, FRP, GFRP, or a bake material) 3 and a superconducting wire formed by winding a superconducting wire near a central portion inside the frame portion 3. Part 4. A heating heater 5 is provided between the respective frame portions 3 of the adjacent switch elements 2,
Heating heaters 5 are also provided between the holding plates 6 at both ends and the frame portions 3 of the switch elements 2 opposed thereto. The holding plate 6 does not have the superconducting wire winding portion 4 formed on the inside like the frame portion 3 and has a slightly thinner thickness. However, the holding plate 6 has substantially the same shape and the same material as the frame portion 3. Things.

As shown in FIG. 1B, the heater 5
Is made of a thermoplastic resin 7 having excellent adhesion at extremely low temperatures.
It is bonded between each switch element 2 and between the switch element 2 and the holding plate 6. As the thermoplastic resin 7, for example, a resin mainly containing a copolymer of ethylene and methacrylic acid is used. In addition, an epoxy resin mixed with a filler such as calcium silicate may be used for bonding in order to increase the bonding strength at extremely low temperatures.

FIGS. 2A and 2B are explanatory views showing the positional relationship between the lead portion 8 of the superconducting wire of the permanent current switch 1 and the heater terminal 5a of the heating heater 5, wherein FIG.
(B) is a side view. Superconducting wire outlet 8a connected to lead 8 and heater terminal 5a of heater 5 for heating
Is at least 10 mm or more apart.

In the first embodiment configured as described above, the heating heater 5 is disposed outside the frame portion 3 of the switch element 2, and the heating heater 5, the superconducting wire winding portion 4, Between the superconducting wire outlet 8a and the heater terminal 5a is at least 10 mm or more. I have. Therefore, even if a quench occurs in the superconducting coil in the superconducting magnet device and a high voltage of 1 kV class is applied between the superconducting wire forming the superconducting wire winding part 4 and the heater 5 for heating, the superconducting wire is not The insulation between the heater 5 and the heater 5 is not destroyed.

That is, in the conventional example shown in FIG. 25, the heating heater 78 is a component of the switch element 70.
The superconducting wire winding portion 77 is disposed inside the frame portion 76 and close to the superconducting wire winding portion 77. However, in the first embodiment shown in FIG. 1 and FIG.
Is provided not as one component but as a separate member between the switch elements 2 and between the switch element 2 and the holding plate 6. Since they are sufficiently separated from each other and the frame portion 3 functioning as an insulating member is interposed between the two, they have sufficient withstand voltage.

Further, the structure shown in FIG.
7, a heating heater 78 is arranged in the vicinity of the central portion, and the heating heater 78 must be involved in the course of winding the superconducting wire, which complicates the internal structure and aligns the superconducting wires tightly. There is a fear that it may become a hindrance factor. Therefore, sufficient attention must be paid to the production, which results in an increase in the number of manufacturing steps. However, in the above-described first embodiment, the heating heater 5 is provided outside the frame portion 3, and only the superconducting wire winding portion 4 is formed inside the frame portion 3. Therefore, there is no need to perform an operation of incorporating the heating heater 5 in the course of winding the superconducting wire, and the winding states of the respective switch elements 2 can be made uniform. That is, according to the first embodiment, it is possible to obtain the secondary effect that the internal structure can be simplified, the number of manufacturing steps can be reduced, and the winding quality can be improved.

FIG. 3 is a configuration diagram of a permanent current switch 1A according to a second embodiment of the present invention. FIG. 3 (a) is a perspective view showing the appearance and internal structure of the permanent current switch 1A, and FIG.
FIG. 5 is a partially enlarged cross-sectional view showing the vicinity of the “B” part in FIG. In the second embodiment, a switch element pair is constituted by a pair of adjacent switch elements 2a and 2b, and the permanent current switch 1A is constituted by a plurality of switch element pairs.

Each switch element 2a, 2b has frame portions 3a, 3b and superconducting wire winding portions 4a, 4b formed inside thereof, as shown in FIG. The thickness t1 on the joint surface side of the frame portions 3a and 3b is smaller than the thickness t2 on the opposite side. Therefore, heat generated from the heater 5 is quickly transmitted to the superconducting wires of the superconducting wire winding portions 4a and 4b.

That is, in the first embodiment, FIG.
As shown in (b), the superconducting wire winding part 4 is
Since the heater 5 is disposed almost at the center of the
The distance between the wire and the superconducting wire winding portion 4 becomes large, which is advantageous in terms of withstand voltage, but disadvantageous in terms of thermal conductivity of heat generated from the heater 5 for heating. However, in the second embodiment, by properly setting the values of t1 and t2, insulation breakdown between the superconducting wire and the heater 5 can be reliably prevented even under a high voltage at the time of occurrence of a quench. When the permanent current switch 1A is turned off by energizing the heating heater 5, the off time can be shortened, and the superconducting state can be quickly changed to the normal conducting state.

A fixed flange 9 is provided between each pair of switch elements (the material of the fixed flange 9 may be a heat insulating member such as GFRP or a good heat conductive material such as aluminum, depending on specifications). And a coolant (liquefied helium) can penetrate into the gap formed by the insertion of the fixing flange 9. Therefore, almost uniform cooling can be performed on any switch element constituting the permanent current switch 1A. 3 (a),
In FIG. 1B, illustration of the holding plate 6 shown in FIGS. 1A and 1B is omitted.

FIG. 4 is a perspective view of a switch element 10 constituting a permanent current switch according to a third embodiment of the present invention. In the frame portion 11 of the switch element 10, two storage portions 11a for storing a pair of superconducting wire winding portions 4 are formed, and a groove portion 11b is formed between the winding wire storage portions 11a. I have. And this groove 11b
Inside, a heater 5 for heating is bonded via a thermoplastic resin 7. The permanent current switch according to the third embodiment has substantially the same function as that of the second embodiment. However, one switch element 10 has two superconducting wire winding portions 4. In addition, it can be substantially identified with two switch elements in the first and second embodiments, and the assembling work can be performed more easily.

FIG. 5 is a configuration diagram of a permanent current switch 1B according to a fourth embodiment of the present invention. FIG. 5A is a perspective view showing the appearance and internal structure of the permanent current switch 1B, and FIG.
FIG. 2 is a partially enlarged cross-sectional view showing, in an enlarged manner, the vicinity of a portion “C” in FIG. FIG. 5 differs from FIG. 3 in that the switch elements 2a and 2b have inside frame portions 3a and 3b.
The point is that good heat conductive insulating members 12a and 12b are arranged between both surfaces of the heater 5 and the superconducting wire winding portions 4a and 4b.

The good heat conductive insulating members 12a, 12b
Is formed of, for example, a donut-shaped thin aluminum nitride plate. By providing the good heat conductive insulating members 12a and 12b between the heating heater 5 and the superconducting wire winding portions 4a and 4b, the permanent current switch 1A is turned off by energizing the heating heater 5. Can be further shortened than in the case of FIG.

FIGS. 6A and 6B are configuration diagrams of a permanent current switch 1C according to a fifth embodiment of the present invention. FIG. 6A is a perspective view showing the appearance and internal structure of the permanent current switch 1C, and FIG.
FIG. 3A is a partially enlarged cross-sectional view showing the vicinity of a “D” part in FIG. 4A, and FIG. Although the good heat conductive insulating members 12a and 12b in FIG. 5 are formed of donut-shaped thin aluminum nitride plates, the good heat conductive insulating members 12c and 12c in FIG.
d is formed by a plurality of small disk-shaped thin aluminum nitride chips. According to the configuration of FIG. 6, during the assembling work, the good heat conductive insulating members 12c and 12d
By adjusting the number of times, it is possible to finely set the off time when the permanent current switch 1A is turned off by energizing the heating heater 5.

FIG. 7 is a structural view of the heater 5 used in the first to fifth embodiments described above.
(A) is a plan view, (b) is a side view. The heating heater 5 has a resistor 13 connecting between the two heater terminals 5a. The resistor 13 is formed by a first resistor portion 13a, a second resistor portion 13b, and a folded portion 13c. I have. The resistor 13 is covered with an insulator 14. In the above embodiment, it is assumed that a heat-resistant film member such as a polyimide film is used as the insulator 14. However, two donut-shaped thin GFRP plates are provided on the upper surface and the lower surface of the resistor 13. To insulator 1
4, it is also possible to adopt a configuration in which the two GFRP plates are bonded with a thermoplastic resin having good thermal conductivity.

In FIG. 7A, the first resistor portion 1
3a extends spirally from one heater terminal 5a to the folded portion 13c on the center side, and the second resistor portion 13b spirals from the folded portion 13c to the other heater terminal 5a. It extends in a shape. That is, the current flowing through the first resistor portion 13a and the current flowing through the second resistor portion 13b are opposite to each other, and a non-inductive circuit that can cancel each other's magnetic field fluctuation is formed. It has been done.

FIGS. 8 to 11 are structural diagrams of modified examples 5A to 5D of the heater 5 shown in FIG. That is, in the heating heater 5A of FIG. 8, a common connection portion 13d is formed between the first resistor portion 13a and the second resistor portion 13b instead of a folded portion. According to this configuration, after the first resistor portion 13a and the second resistor portion 13b are separately formed, their ends may be twisted together to form the common connection portion 13d. Can be manufactured.

In the heating heater 5B shown in FIG. 9, common connection portions 13e and 13f are formed near the heater terminal 5a. Also in this configuration, the first resistor portion 13a
And the second resistor portion 13b are separately formed,
The heaters can be easily manufactured because the common connection portions 13e and 13f may be formed by welding the ends of the resistor portion 13b to the first resistor portion 13a.

As shown in FIG. 10A, the heater 5C for heating shown in FIG. 10 is a thin plate-shaped resistor 13A having a certain width.
Is formed in a spiral shape. And the resistor 13
Two doughnut-shaped thin plates G on the upper and lower sides of A
An FRP plate is attached as an insulator 14A, and the two G
The FRP plate is bonded with a thermoplastic resin 7. However, a heat-resistant film member such as the above-described polyimide film may be used as the insulator 14A.

The heating heater 5D shown in FIG. 11 is formed by forming a thin-plate-shaped resistor 13A into a "sail-fold" shape.
The other points are the same as those of the heater 5C shown in FIG. Note that the thin-plate resistor 13A in FIGS. 10 and 11 is harder to deform than the thin-wire resistor 13 in FIGS.
When 3A is used, it is not always necessary to cover with the insulator 14A, and it is also possible to adopt a configuration in which the resistor 13A is directly disposed between the switch elements. 3, it is not necessary to overlap and cover with the insulator 14A from the viewpoint of the insulating function.)

FIG. 12 is a configuration diagram of a permanent current switch 1D according to a sixth embodiment of the present invention. The heating heater in the above-described embodiment is arranged between the frame portions of the switch elements superposed in the thickness direction (FIGS. 1, 3, 5, and 6) or in the thickness direction in the frame portions. In this embodiment, a heating heater is provided outside the superconducting wire winding portion in the radial direction of the frame portion, between the pair of superconducting wire winding portions. Is arranged.

That is, each switch element 2 of the permanent current switch 1D includes a frame portion 3p and this frame portion 3p
And a frame portion 3q arranged outside the frame. The superconducting wire winding section 4 is provided inside the frame section 3p, and the heating heater 15 is provided inside the frame section 3q. The shape of the heating heater 15 is different from the heating heater 5 shown in FIGS. 7 to 9 as a matter of course, but the basic structure is substantially the same and the resistor is not provided. It forms an induction circuit. As described above, since the heating heater 15 is disposed outside the frame portion 3p in the radial direction, the length in the thickness direction of the plurality of switch elements 2 (the axial length of the permanent current switch 1D). ) Can be shortened accordingly, and the degree of freedom in design can be increased. The superconducting wire winding section 4 and the heating heater 15 are disposed in the respective frame sections 3p and 3q, respectively. These frame sections 3p and 3q are integrally formed and are formed in the same frame. It may be configured to be disposed.

FIG. 13 is a configuration diagram of a permanent current switch 1E according to a seventh embodiment of the present invention. In FIG. 12, the heating heater 15 is provided outside the superconducting wire winding portion 4, but in this embodiment, the heating heater 15 is provided inside the superconducting wire winding portion 4. is there. According to this embodiment, the degree of freedom in design can be increased as in the case of FIG.

FIG. 14 is a configuration diagram of a permanent current switch 16 according to the eighth embodiment of the present invention. The permanent current switch 16 has a plurality of substantially cylindrical switch elements 17, and these switch elements 17 are electrically connected in parallel by a lead portion 18. Both ends of the plurality of switch elements 17 are attached to the holding plate 19. Each switch element 17 has a frame portion 20 made of a material such as FRP or GFRP, and a superconducting wire winding portion 21 is provided in the frame portion 20. A heater 22 is provided on the inner peripheral surface of the frame portion 20 inside the superconducting wire winding portion 21. The heating heater 22 has a structure in which a resistor is covered with a heat-resistant film member such as a polyimide film, similarly to the heating heater 5 in each of the above-described embodiments. Is adhered to the inner peripheral surface of the. The heater 22 has a resistor forming a non-inductive circuit, similarly to the heater 5 shown in FIGS. 7 to 11.

According to the configuration shown in FIG. 14, since the heating heater 22 and the superconducting wire winding section 21 are sufficiently separated from each other with the frame section 20 as an insulating member interposed therebetween. As in the embodiments described above, dielectric breakdown between the superconducting wire and the heater 22 can be reliably prevented. Further, in this embodiment, since the heating heater 22 is disposed outside the frame portion 20, it is not necessary to perform an operation of incorporating the heating heater 22 during winding of the superconducting wire. The winding state of each switch element 17 can be made uniform. Therefore, it is possible to reduce the number of manufacturing steps by simplifying the internal structure, and to obtain a secondary effect that the winding quality can be improved.

FIG. 15 is a configuration diagram of a permanent current switch 16A according to the ninth embodiment of the present invention. In the configuration of FIG. 14, the heating heater 22 is adhered on the inner peripheral surface of the frame portion 20. In the configuration of FIG. 15, the heating heater 22A is adhered on the outer peripheral surface of the frame portion 20. It is the configuration that was done. Other configurations and effects are the same as those of the configuration in FIG.

FIGS. 16 and 17 are perspective views of switch elements 17B and 17C constituting the permanent current switch according to the tenth and eleventh embodiments of the present invention. In the configurations of FIGS. 14 and 15, the heaters 22 and 22A are mounted on the inner peripheral surface and the outer peripheral surface of the frame portion 20, respectively. However, in the configurations of FIGS. Are formed inside the superconducting wire winding section 21, and the heaters 22 and 22A are disposed inside and outside the superconducting wire winding section 21, respectively.

14 and 15, the heaters 22 and 22A are exposed to the outside of the frame portion 20, but in the configurations of FIGS. 16 and 17, the heaters 22 and 22A are heated. Is not exposed to the outside and is housed in the frame portion 20, so that it is possible to prevent an accident such as damage to the heater surface during a wiring operation or the like.

Although the permanent current switch of each of the above embodiments has been described as an example used for a superconducting magnet of a magnetic levitation train, the technique of the permanent current switch of the present invention is not limited to this. However, the present invention can be widely applied to an apparatus for controlling a transition between a superconducting state and a normal conducting state. Further, the numerical values, materials, and the like in the above description are not limited thereto, and various changes are possible as long as the objects of the present invention are met.

[0060]

As described above, according to the present invention, the heating heater is arranged by interposing the insulating member between the superconducting wire winding portion and the superconducting wire winding portion. Being sufficiently separated from the wire winding section, it is possible to reliably prevent the insulation between the superconducting wire and the heater from being broken even when a high voltage due to the quench of the superconducting wire is applied. it can.

Further, by adopting the above configuration, as a result, only the superconducting wire winding portion is accommodated inside the frame portion, so that the internal structure can be simplified and the superconducting wire winding can be performed. A secondary effect that the line quality can be improved can be obtained.

[Brief description of the drawings]

FIGS. 1A and 1B are configuration diagrams of a permanent current switch 1 according to a first embodiment of the present invention, wherein FIG. 1A is a perspective view showing the appearance and internal structure of the permanent current switch 1, and FIG. FIG. 3 is a partially enlarged cross-sectional view showing the vicinity of “A” in an enlarged manner.

FIGS. 2A and 2B are explanatory diagrams showing a positional relationship between a lead portion 8 of a superconducting wire of the permanent current switch 1 and a heater terminal 5a of a heater 5 in FIG. 1; FIG.
(B) is a side view.

FIG. 3 is a configuration diagram of a permanent current switch 1A according to a second embodiment of the present invention, where (a) is a permanent current switch 1A.
FIG. 2B is a perspective view showing the external appearance and the internal structure of FIG.

FIG. 4 is a perspective view of a switch element constituting a permanent current switch according to a third embodiment of the present invention.

FIG. 5 is a configuration diagram of a permanent current switch 1B according to a fourth embodiment of the present invention, where (a) is a permanent current switch 1B.
FIG. 2B is a perspective view showing the external appearance and the internal structure of FIG.

FIG. 6 is a configuration diagram of a permanent current switch 1C according to a fifth embodiment of the present invention, where (a) is a permanent current switch 1C.
FIG. 2B is a perspective view showing the external appearance and internal structure of FIG.
(C) is a side view of the permanent current switch 1C.

FIGS. 7A and 7B are configuration diagrams of a heating heater 5 used in the first to fifth embodiments of the present invention, wherein FIG. 7A is a plan view and FIG. 7B is a side view.

8 is a configuration diagram of a modification 5A of the heater 5 shown in FIG.

9 is a configuration diagram of a modification 5B of the heater 5 shown in FIG.

FIG. 10 is a configuration diagram of a modification 5C of the heater 5 shown in FIG. 7;

11 is a configuration diagram of a modification 5D of the heater 5 shown in FIG.

FIG. 12 is a configuration diagram of a permanent current switch 1D according to a sixth embodiment of the present invention.

FIG. 13 is a configuration diagram of a permanent current switch 1E according to a seventh embodiment of the present invention.

FIG. 14 is a configuration diagram of a permanent current switch 16 according to an eighth embodiment of the present invention.

FIG. 15 is a configuration diagram of a permanent current switch 16A according to a ninth embodiment of the present invention.

FIG. 16 is a perspective view of a switch element 17B constituting a permanent current switch according to a tenth embodiment of the present invention.

FIG. 17 is a perspective view of a switch element 17C constituting a permanent current switch according to an eleventh embodiment of the present invention.

FIG. 18 is an electric circuit diagram for explaining a process of creating a permanent current mode by using a thermal permanent current switch.

FIG. 19 is a cross-sectional view showing a schematic configuration of a magnetic levitation train.

20 is a perspective view showing a configuration of a superconducting magnet device 56 and a cooling device 58 in FIG.

FIG. 21 is a view taken in the direction of arrows AA in FIG. 20;

FIG. 22 is a view taken in the direction of arrows BB in FIG. 21;

FIG. 23 is a perspective view showing an external configuration of the permanent current switch 66 in FIGS. 20 to 22;

FIG. 24 is a perspective view showing an external configuration of a permanent current switch 71 of a type different from the above-described permanent current switch 66.

FIG. 25 is a partially broken sectional view showing the internal structure of the permanent current switch 66 shown in FIG. 23;

26 is a partially broken sectional view showing the internal structure of the permanent current switch 71 shown in FIG. 24.

[Explanation of symbols]

1, 1A, 1B, 1C, 1D, 1E Permanent current switch 2, 2a, 2b Switch element 3, 3a, 3b, 3p, 3q Frame part 4, 4a, 4b Superconducting wire winding part 5, 5A, 5B, 5C, 5D Heating heater 5a Heater terminal 6 Holding plate 7 Thermoplastic resin 8 Lead 9 Fixing flange 10 Switch element 11 Frame 11a Winding wire housing 11b Groove 12a, 12b Good heat conductive insulating member (aluminum nitride plate) 12c, 12d Good thermal conductive insulating member (aluminum nitride chip) 13, 13A Resistor 13a First resistor portion 13b Second resistor portion 13c Folded portion 13d, 13E, 13F Common connection portion 14, 14A Insulator 15 Heating Heater 16, 16A Permanent current switch 17, 17A, 17B, 17C Switch element 18 Lead 9 Holding plate 20 Frame part 21 Superconducting wire winding part 22, 22A Heating heater 23 Frame part 24 Frame part 51 Maglev train 52 Guideway 53 Body 54 Dolly 55 Wheel 56 Superconducting magnet device 57 Superconducting coil 58 Cooling device 59 Propulsion Coil 60 Refrigerator 61 Coolant tank 62 Outer tank 53 Heat shield plate 64 Inner tank 65 Load support material 66 Permanent current switch 67 Inner container for switch 68 Lead part 69 Lead part 70 Switch element 71 Permanent current switch 72 Switch element 73 Lead Part 74 Holding plate 75 Fixing flange 76 Frame part 77 Superconducting wire winding part 78 Heating heater 79 Frame part 80 Superconducting wire winding part 81 Heating heater

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Tomohisa Yamashita 1 Toshiba-cho, Fuchu-shi, Tokyo F-term in the Toshiba Fuchu Plant (reference) 4M114 AA14 AA21 AA30 BB01 CC03 DA53 DA54 DB13 DB23 DB24 5J050 AA38 AA47 CC01 DD16

Claims (15)

[Claims] A plurality of switch elements having a superconducting wire winding portion formed by winding a superconducting wire inside an insulating frame portion, wherein the plurality of switch elements are immersed in a coolant; It is electrically connected in parallel in a state in which the superconducting wire is wound around the superconducting wire. In a thermal permanent current switch for performing transition and controlling the generated resistance of the superconducting wire, an insulating member is interposed between the superconducting wire winding portion and the heating member separately from the superconducting wire winding portion. A permanent current switch characterized by the above arrangement. 2. The plurality of switch elements are joined to each other in a state where respective flat heat-insulating frame portions are overlapped in the thickness direction thereof, and the heating heater is connected to an adjacent switch element. The permanent current switch according to claim 1, wherein the permanent current switch is disposed between the respective flat heat-insulating frame portions. 3. The flat heat-insulating frame of the switch elements constituting each switch element pair, wherein the plurality of switch elements are constituted by a combination of a plurality of switch element pairs constituted by a pair of switch elements adjacent to each other. The permanent current switch according to claim 2, wherein the heater for heating is disposed between joining surfaces of the portions. 4. The permanent current switch according to claim 3, wherein the thickness of the flat heat-insulating frame portion on the joining surface side is formed smaller than the thickness of the opposite side. 5. The plurality of switch elements are joined in a state where respective flat heat-insulating frame portions are overlapped in the thickness direction thereof, and the flat heat-insulating frame portions of the switch elements are provided. The pair of superconducting wire winding portions are disposed inside, and the heating heater is disposed in a groove formed between the pair of superconducting wire winding portions. Permanent current switch. 6. The plurality of switch elements are joined in a state where respective flat heat-insulating frame portions are overlapped in a thickness direction thereof, and the heater is a flat plate of each switch element. The inside of the flat heat-insulating frame portion and disposed outside or inside the superconducting wire winding portion on the radial direction of the flat heat-insulating frame portion. Permanent current switch. 7. A plurality of heat-insulating frame portions of said plurality of switch elements have a cylindrical shape, and said plurality of cylindrical heat-insulating frame portions are bundled such that respective end faces thereof are substantially on the same plane. The heater for heating is arranged on the inner peripheral surface or the outer peripheral surface of the cylindrical heat-insulating frame part of each switch element. Item 4. The permanent current switch according to Item 1. 8. A plurality of heat insulating frame portions of the plurality of switch elements have a cylindrical shape, and the plurality of cylindrical heat insulating frame portions are bundled such that respective end faces thereof are located substantially on the same plane. Wherein the heating heater is disposed inside the cylindrical heat-insulating frame portion of each switch element and inside or outside the superconducting wire winding portion. The permanent current switch according to claim 1, wherein: 9. The heating heater is bonded to the heat-insulating frame with a thermoplastic resin containing a copolymer of ethylene and methacrylic acid as a main component or an epoxy resin mixed with a filler such as calcium silicate. The permanent current switch according to any one of claims 1 to 8, wherein: 10. The permanent current switch according to claim 1, wherein a good heat conductive insulating member is provided between the heating heater and the superconducting wire winding portion. . 11. The heat-conductive insulating member according to claim 10, wherein the high-heat-conductive insulating member is disposed in a spot-like manner between the heating heater and the superconducting wire winding portion. Permanent current switch. 12. The heating heater according to claim 1, wherein a direction of a current in a certain resistor portion is opposite to a direction of a current in another resistor portion disposed along the resistor portion. The permanent current switch according to any one of claims 1 to 11, wherein a non-inductive circuit that cancels out is formed. 13. The permanent current switch according to claim 12, wherein the heater has a folded portion formed between the certain resistor portion and the other resistor portion. . 14. The heating heater according to claim 1, wherein a common connection portion is provided for connecting the certain resistor portion and the other resistor portion so that a folded portion is not formed. The permanent current switch according to claim 12, wherein 15. The device according to claim 1, wherein a distance between the superconducting wire lead-out portion of the switch element and a heater terminal of the heating heater is at least 10 mm or more. Permanent current switch.