JP2010004646A - Superconducting rotating machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a superconducting rotating machine which reduces leakage magnetic field, by bringing length of an iron core in a rotor axis direction close to the width of the axial direction of a superconducting coil stored in an inner vessel. <P>SOLUTION: In a rotor and a stator, in which magnetic pole face sides confront each other in parallel, while leaving a gap, the superconducting coil is arranged around the iron core, on at least a stator side as an armature. The superconducting coil is stored in the inner tank of an inner/outer double-wall structure tank, formed of an outer tank and the inner vessel which is a container whose external shape is cylindrical. A cooling medium, circulating through cooling medium piping through joints, arranged on an outer tank wall and an inner vessel wall for cooling the superconducting coil is stored in the inner tank. The space between the outer vessel and the inner vessel is set as a vacuum insulating layer. The cooling medium which pipes through joints and current inlet terminal through joints are disposed in the body of the inner vessel in the superconducting rotating machine. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to superconductivity (also referred to as superconductivity) in which a superconducting coil that constitutes a part of a superconducting motor, generator, etc. used in ships, railways, land vehicles, aircraft, etc. is housed in a cryostat made of FRP. Yes.) It relates to rotating equipment.

In recent years, a superconducting motor using a superconducting coil as an armature coil or a field coil in a synchronous machine using an AC power source has been developed, and attempts have been made to apply it to ships, railways, land vehicles, airplanes and the like. Patent Documents 1 to 3 disclose a method for forming an FRP cryostat comprising an outer tub and an inner tub that accommodates such a superconductor and having a vacuum heat insulating layer between the outer tub and the inner tub. Further, it is necessary to dispose a cooling medium pipe and a through joint for a current introduction terminal on the wall portion of the FRP cryostat. Such a through joint or the like is provided with a metal member penetrating the cryostat. Although it was fixed by joining a through joint or the like, it was a place that caused vacuum leakage of the vacuum heat insulating layer due to various stresses such as thermal stress during cooling and heating.
Applicants have studied a method for preventing vacuum leakage of a vacuum heat insulating layer when a metal member is fixed to an FRP cryostat and a penetration joint or the like is joined to the member. This is disclosed in Document 4.

Usually, as an example of a superconducting motor, for example, in a synchronous machine, (i) when a superconducting coil is used for the field, a normal conducting coil is used for the armature, (ii) when a superconducting coil is used for the armature, and a permanent magnet is used for the field, (Iii) The case where a superconducting coil is used for both the armature and the field is considered.
In the superconducting motor using the superconducting coil for both the armature and the field in Patent Document 5 filed earlier, the applicants cooled the superconducting coil in the inner case (hereinafter referred to as the inner tank). The space between the outer case (hereinafter referred to as the outer tub) and the inner tub is a vacuum heat insulating layer, and the outer tub of the case containing the superconducting coil is filled with a cooling medium. A columnar body extending along the direction in which the stator and the rotor face each other and penetrating the inner peripheral side of the inner tank and the superconducting coil is disposed, and both ends of the columnar body are in contact with the inner surface of the outer tank. And the structure which prevents the deformation | transformation to the inner side of an outer tank with the columnar body was proposed. By adopting such a configuration, even if the outer wall of the vacuum heat insulating layer, that is, the wall of the outer tub is thinned, the outer case wall is not deformed due to the pressure difference from the atmospheric pressure. The distance between the magnetic pole faces of the rotor and stator can be made smaller than before, and as a result, the rotational output (torque) as a superconducting motor can be increased.

In Patent Document 6, as a cooling structure of a superconducting motor having a superconducting coil attached to the rotor side, a groove is provided in the outer surface of a rotating shaft that is fixed by penetrating the rotor. A superconducting motor characterized by being inserted and disposed in the groove is disclosed.
Patent Document 7 requires a stator in the axial direction of a rotor as a rotary field type axial gap motor in which a rotor including a permanent magnet and a stator including an armature winding face each other in the axial direction. A plurality of field bodies are arranged around the axis on either one of the rotor and the stator, and a plurality of armature coils are arranged around the axis on either one of the rotor and the stator. A superconducting motor is disclosed in which at least one of the field body and the armature coil is formed of a superconducting material, and the magnetic flux direction is arranged in the axial direction.

Japanese Patent Laid-Open No. 61-210603 JP 2007-035835 A JP 2007-210325 A JP 2007-214546 A JP 2006-187136 A JP 2006-187051 A JP 2006-204085 A

The inner tank of a cryostat that houses superconducting coils of superconducting rotating equipment such as superconducting motors used in ships, railways, land vehicles, and aircraft is usually cylindrical in shape (for example, the lotus root is the central axis). Since the body of the container has a curved surface, all metal penetration joints conventionally have a top cover when the rotation axis of a superconducting motor or the like is in the vertical direction. Left or right side surface that is a cylindrical flat surface when the rotation axis is horizontal (hereinafter, the upper lid or lower bottom plate when the rotation axis of a superconducting motor or the like is vertical) And the left and right side surfaces when the rotation axis is horizontal are collectively referred to as “cylindrical upper lid, lower bottom plate or flat side”, and the outer and inner tanks. Prevents vacuum leakage of the vacuum insulation layer between Was it possible to specific operation.
Even when a metal penetration joint is provided in the outer tank body of the superconducting rotating machine, the cooling medium pipe and the current introduction cord are connected to the outer surface of the inner tank in the vacuum heat insulating layer region between the outer tank and the inner tank. A cooling medium pipe penetration joint and a current introduction terminal penetration joint were arranged on the cylindrical upper lid portion or lower bottom plate portion of the inner tank or the side surface portion that is a flat portion along the vicinity of the portion.

For example, Patent Document 6 discloses a cooling structure for a superconducting motor in which a superconducting coil is attached to a rotor, and a groove is formed in the outer surface of a rotating shaft that is fixed through the rotor and inserted into the groove. A cooling structure for a superconducting motor is disclosed in which a refrigerant is circulated through a refrigerant circulation pipe and a superconducting coil is cooled by the refrigerant. Patent Document 7 discloses a structure in which penetration joints are arranged on both side surfaces.
Neither of the above-mentioned patent documents 6 and 7 discloses disposing a metal through-joint on the body of the inner tank.

By the way, not only a superconducting motor but generally a motor, in order to generate a sufficient rotational output, in order to generate a sufficient rotational output, an interval between the mutually opposing rotor side magnetic pole surface and stator side magnetic pole surface (the interval is an internal It is desirable to make the wall thickness of the tank and the outer tank, the vacuum heat insulating layer, and the gap as small as possible.
Further, in the prior art, the metal penetration joint is provided on the FRP flat plate portion of the “cylindrical upper lid portion or lower bottom plate portion or the side portion which is a flat portion” as described above. A structure that minimizes the thickness of the other vacuum heat insulating tank by collecting it in any one of the “cylindrical upper lid portion, lower bottom plate portion, or side portion that is a flat portion” has been considered.
In Patent Document 5, in order to reduce the distance between the magnetic pole surface on the rotor side and the magnetic pole surface on the stator side, the wall thicknesses of the inner tank and the outer tank are reduced, thereby reducing the rigidity and reducing the outer thickness. In order to prevent the tank from deforming to the inner tank side and coming into contact with the outer surface of the inner tank to impair the heat insulation effect, the outer tank (outer case) of the case containing the superconducting coil has a stator and It is disclosed that a columnar body extending along a direction facing the rotor and penetrating the inner tub (inner case) and the inner peripheral side of the superconducting coil is disclosed.

However, on the side where the through joints are arranged, the cooling medium inflow and outflow pipes and the current introduction terminals (current lead wires) are connected via these joints, so that they face the inner tank wall on that side. As a result of the cooling medium inflow and outflow piping and the current introduction terminal being attached to the vacuum heat insulating layer between the outer tank wall and the outer tank wall, there remains a problem that the vacuum heat insulating layer has a large thickness (for example, about 50 mm). For example, in Patent Document 5, since the columnar body penetrates the inner peripheral side of the superconducting coil and is in contact with both inner surfaces of the outer tub, the iron core housed inside the columnar body forming the magnetic flux lines is more than the superconducting coil. However, there is a problem that the length in the axial direction becomes longer.
FIG. 1 shows a conceptual diagram of a cross section of a superconducting rotating machine to which the structure disclosed in Patent Document 5 is applied. As shown in FIG. 1, in a synchronous machine using a rotor as a field and a stator as an armature, the superconducting coil and the iron core are sufficiently close to each other, but the length of the iron core is the rotor of the cylindrical container. Due to the large thickness of the vacuum heat insulating layer in the axial direction, it becomes longer than the width of the superconducting coil, which is the stator, in the direction of the rotation axis. There was a problem that the magnetic flux increased and the rotational output could not be improved.

  The present invention has been made against the background of the above circumstances, and a superconducting coil is an iron core as an armature inside an inner tub of an outer tub and an inner and outer double-walled tub composed of an inner tub that is a cylindrical container as a whole. In the superconducting rotating device housed around the flat plate portion on both sides of the inner tank, by disposing a through joint for cooling medium piping and a through joint for current introduction terminal in the cylindrical body of the inner tank And the superconducting coil and the permanent magnet are brought close to each other, and the length of the iron core in the rotor axial direction is made closer to the axial width of the superconducting coil. As a result, the inventors have found that the magnetic path can be effectively formed and the rotational output can be improved, and the present invention has been completed.

That is, the present invention is an invention having the gist of the following descriptions (1) to (6).
(1) A superconducting coil is disposed around an iron core as an armature on at least the stator side of a rotor and a stator whose magnetic pole face sides are opposed to each other in parallel with a gap, and the superconducting coil Is housed in an inner tank of an inner / outer double wall structure tank with an outer tank and an inner tank whose outer shape is a cylindrical container, and the outer tank is used for cooling the superconducting coil. A superconducting material that contains a cooling medium that is circulated through a through hole for cooling medium piping disposed on the tank wall and the inner tank wall, and in which the space between the outer tank and the inner tank is a vacuum heat insulating layer. A superconducting rotary device (hereinafter referred to as a first mode), characterized in that a through-joint for cooling medium piping and a through-joint for current introduction terminal are disposed in a body portion of the inner tank. is there).
(2) The superconducting rotary device according to (1), wherein the inner tank is an inner tank formed of fiber-reinforced plastic (hereinafter, sometimes referred to as a second aspect).
(3) The above-mentioned (1), wherein a flat portion is provided on at least a part of the body portion of the inner tank, and a through joint for cooling medium piping and a through joint for current introduction terminal are disposed on the flat portion. Alternatively, the superconducting rotary device according to (2) (hereinafter sometimes referred to as a third aspect).
(4) The flat portion provided in at least a part of the body portion of the inner tub is a flat portion integrally formed with the wall of the inner tub when the inner tub is formed. (3) The superconducting rotating device (hereinafter, sometimes referred to as a fourth aspect).
(5) The superconducting rotation as described in (3) above, wherein the flat portion provided in at least a part of the body portion of the inner tank is a flat portion provided by bonding a seat made of FRP. Equipment (hereinafter sometimes referred to as fifth aspect).
(6) The superconducting rotating machine is an axial type superconducting motor in which a permanent magnet is fixed as a field magnet on the rotor side and a superconducting coil is disposed as an armature on the stator side. ) To the superconducting rotating device according to any one of (6) (hereinafter may be referred to as a sixth embodiment).

  In the “superconducting rotating device” described in the first aspect, a through joint for cooling medium piping and a through joint for current introduction terminal are disposed on the body of the inner tank in which the superconducting coil is housed. Until the "cylindrical upper lid or lower bottom plate or side surface that is a flat surface", the cooling medium pipe penetration joint and the current introduction terminal penetration joint are connected to the cylindrical upper lid or lower part. Since it is not necessary to arrange in the side plate part which is a bottom plate part or a plane part, the thickness of the vacuum heat insulation layer between the inner tank and the outer tank in the part (the upper lid part or the lower bottom plate part or the side part) is reduced. Thus, in a superconducting rotary motor or the like, the hollow cylindrical superconducting coil axial width of the motor armature coil (width in the rotational axis direction of the drive shaft) has a double-sided permanent magnet as a field. Arranged between Thus, the length of the iron core forming the magnetic path in the hollow portion of the superconducting coil can be made closer, and as a result, magnetic flux leakage can be suppressed and the magnetic path is more effectively formed to further improve the rotational output. be able to.

Since the inner tank in the “superconducting rotating machine” according to the second aspect 2 is formed of fiber reinforced plastic, an eddy current is generated in the interior due to the magnetic fluctuation that occurs when a metal material is used. Thus, inconveniences such as distortion in the magnetic field can be avoided.
In the “superconducting rotating device” described in the third aspect, the outer shape in which the superconducting coil is accommodated is generally cylindrical (specifically, as shown in FIGS. 3 and 4, the lotus root is the central axis. Since the flat part is provided in at least a part of the body part of the inner tub of the shape cut in the vertical direction (hereinafter referred to as “the outer shape may be a cylindrical shape”), the coolant pipe is provided in the flat part. By providing the through joint for use and the through joint for the current introduction terminal, it becomes possible to effectively prevent vacuum leakage.
The flat portion provided in at least a part of the inner tank body in the “superconducting rotating device” according to the fourth aspect is formed integrally with the inner tank body when the inner tank is formed. Therefore, it is not necessary to provide a connection part, an adhesive part, etc. for forming the flat part, vacuum leakage can be further reduced, and the influence of various stresses such as thermal stress can be reduced for a longer period of time. Stable operation becomes possible.

Since the plane part provided in at least a part of the trunk of the inner tank in the “superconducting rotating device” according to the fifth aspect is a plane part provided by adhering a seat made of FRP, the plane It is relatively easy to select the formation place of the part, and the flat part can be intermittently formed on the body curved surface by post-processing.
Since the “superconducting rotating device” described in the sixth aspect is an axial superconducting motor in which a permanent magnet is fixed as a field on the rotor side and a superconducting coil is disposed as an armature on the stator side, In a superconducting rotary motor or the like, the width of the hollow cylindrical superconducting coil, which is the armature coil of the motor, is arranged between the permanent magnets on both sides of the field, and is magnetized in the hollow portion of the superconducting coil. The length of the iron core forming the path can be reduced, and as a result, the magnetic path can be more effectively formed and the rotational output can be improved.

  In the “superconducting rotating device” of the present invention, a superconducting coil is disposed around an iron core as an armature on at least the stator side of a rotor and a stator whose magnetic pole face sides are opposed to each other in parallel with a gap. And the superconducting coil is housed in an inner tub of an inner and outer double wall structure tub with an outer tub and an inner tub whose outer shape is a cylindrical container. In order to cool the coil, a cooling medium circulated through a cooling medium pipe penetration joint disposed on the outer tank wall and the inner tank wall is accommodated, and a space between the outer tank and the inner tank is further provided. A superconducting rotary device with a vacuum heat insulation layer, in which a flat portion is provided on at least a part of the trunk of the inner tank, and a through joint for cooling medium piping and a through joint for current introduction terminal are provided on the flat portion. It is characterized by being.

Hereinafter, the superconducting rotary device of the present invention will be described.
In the superconducting rotating device of the present invention, a superconducting coil is disposed around the iron core as an armature on at least the stator side of the rotor and the stator facing each other with a gap in parallel on the magnetic pole surface side. In addition, the superconducting coil is housed in an inner tank of an inner / outer double wall structure tank of an outer tank and an inner tank that is a cylindrical container as a whole, and the superconducting coil is cooled in the inner tank. The cooling medium circulated through the cooling medium pipe penetration joint disposed on the outer tank wall and the inner tank wall is housed, and the space between the outer tank and the inner tank is a vacuum heat insulating layer. The present invention can be applied to a superconducting rotating device, and is not limited to a superconducting motor, but can also be applied to a superconducting generator.

For example, in a superconducting motor, a superconducting coil is disposed around an iron core as an armature at least on the stator side, and the superconducting coil is accommodated in an inner tank which is a cylindrical container as a whole. If the structure is such that the rotor side is a permanent magnet or a superconducting coil, the present invention can be applied. Conventionally, a rotor (field) is generally manufactured by a superconducting coil and a stator (armature) is manufactured by a copper coil. However, in the superconducting rotating device of the present invention, the stator (armature) is used. The present invention can also be applied to an axial type that uses a superconducting coil and uses a permanent magnet as a rotor (field). Below, it demonstrates using FIGS. 2-5 as an example of the superconducting rotary apparatus of this invention.
2 to 5 are exemplifications of the present invention, and the present invention is not limited to the superconducting rotating device shown in these drawings.

[1] Structural Example of Superconducting Rotating Device of the Present Invention As a structural example of the superconducting rotating device of the present invention, a superconducting coil is formed as an armature coil around an iron core 13 on the stator side in a synchronous machine using an AC power source in FIG. 11 is a conceptual cross-sectional view of an axial type superconducting motor in which a permanent magnet 12 is fixed to the rotor as a field.
In FIG. 2, the permanent magnet 12 that is the magnetic field on the rotor side and the superconducting coil 11 that is the armature coil on the stator face each other in parallel with a gap therebetween.
The superconducting coil 11 is housed inside the inner tank of the inner / outer double wall structure tank composed of the outer tank 1 and the inner tank 2, and the inner tank 2 cools the superconducting coil 11 in the inner tank 2. The cooling medium 4 circulated through the through hole for the cooling medium pipe disposed on the inner tank wall is accommodated, and the vacuum heat insulating layer 3 is provided between the outer tank 1 and the inner tank 2. . As the cooling medium, liquid helium, liquid nitrogen or the like can be used, but use of liquid nitrogen is preferable. On the rotor side, the permanent magnet 12 is fixed to the drive shaft 16 via the main yoke 15 and the sub yoke 14.

[2] Inner tank and outer tank of the superconducting rotating device of the present invention The inner tank in which the superconducting coil is accommodated cools the conductive coil with a cooling medium such as liquid nitrogen, and is located at the center of the magnetic flux, and the outer tank A vacuum heat insulating layer is formed in the space between the two. Therefore, the inner tub prevents the gas leakage and liquid leakage of the cooling medium by maintaining the necessary mechanical strength and heat insulation, and further, the magnetic flux from the superconducting coil as the armature is a permanent magnetic field. It is necessary to have a structure that can prevent leakage as much as possible while reaching the magnet or superconducting coil.
In addition, the outer tank has an inner tank and an iron core inside, and as with the inner tank, the formation of the vacuum heat insulating layer and the leakage of magnetic flux reaching the field from the armature as much as possible are prevented as much as possible. It is necessary to make it a structure.
Accordingly, if the inner tank and / or the outer tank are made of a metal material, an eddy current or the like may be generated in the interior due to the change in magnetism, and the magnetic field may be distorted. ).

As such a fiber reinforced plastic (FRP), it is preferable to use at least one fiber reinforced plastic selected from glass fiber reinforced plastic, boron fiber reinforced plastic, and aramid fiber reinforced plastic. Fiber reinforced plastic is preferred. In addition, although it is possible to form an inner tank with a carbon fiber reinforced plastic, since it has electroconductivity, there exists a possibility of producing the said problem.
When molding a FRP cryostat, unlike metal, welding is not possible. For example, a bottomed cylindrical container body serving as a cryostat body and an upper opening of the container body It can be manufactured by combining a plate-like lid member to be adhered and bonding them together (see, for example, Patent Document 1).

  Also, an inner tank frame is fabricated by assembling the mold outer cylinder, the mold inner cylinder, and the mold side plate, and the FRP prepreg is laminated on the entire surface of the inner tank frame, and the prepreg is cured to prepare the FRP cryostat. It can be manufactured (see, for example, Patent Document 2). These formwork members are cylindrical or plate-like molded products obtained by impregnating a thermosetting resin such as epoxy resin or unsaturated polyester resin into a cloth or mat of reinforcing fibers such as glass fiber and curing it. It is. By integral molding of the FRP prepreg, liquid leakage and gas leakage can be prevented even when high internal pressure and thermal stress are applied, and liquid leakage and gas leakage can be prevented even when high internal pressure and thermal stress are applied.

  Further, the FRP member corresponding to the container body and the plate-like lid member attached to the upper opening of the container body is provided with a tapered surface on the outer surface in the vicinity of the joint, and the end surfaces of both FRP members are formed. FRP that forms polymerized pieces to be polymerized inside and outside, polymerizes the polymerized pieces of each FRP member, laminates the prepreg on the taper surfaces of both joined FRP members, and degass and cures the laminated prepreg A manufactured cryostat can be manufactured (see, for example, Patent Document 3). Furthermore, in the case where a gas impermeable film is inserted, the gas transfer from the inner tank to the vacuum heat insulating layer is suppressed when a cryostat is formed, and the heat insulating performance of the vacuum heat insulating tank can be prevented from being lowered.

[3] Installation of a plane part on a part of the body part of the inner tub and provision of a penetration joint on the plane part. A plane part is installed on a part of the body part of the inner tub 2, and a penetration joint is provided on the plane part. An example of arrangement will be described with reference to FIGS. FIGS. 3A and 4A are plan views of the inner tank, respectively, and FIGS. 3B and 4B are perspective views thereof.
As shown in FIGS. 3B and 4B, the inner tank 2 is a container having a cylindrical outer shape as a whole, and a drive shaft arrangement portion 27 is provided around the central axis of the cylindrical shape. And the iron core arrangement | positioning part 28 is provided centering | focusing on the center axis | shaft of each superconducting coil 11 of a some hollow cylindrical shape.
In the present invention, a through joint for cooling medium piping and a through joint for current introduction terminal disposed in a “cylindrical upper lid portion, lower bottom plate portion, or side portion that is a flat portion” in the present invention are used in the present invention. Examples of the method for disposing the body portion of the tank include the following (a) to (c), but the method for forming the planar portion in the present invention is not limited to these examples. In addition, when the curvature radius of a trunk | curve curved surface is large enough, it may be possible to arrange | position a penetration joint, without providing a plane part especially.

(A) A flat part is provided in advance in the body part of the mold of the inner tank, and a prepreg is laminated on the mold and cured, and the flat part 25 is formed on a part of the body part of the inner tank 2. Molded integrally with the body (see FIG. 3).
(B) An FRP seat (nozzle base) is bonded to a part of the curved surface of the body portion of the inner tank 2 by post-processing to provide a flat portion 29 (see FIG. 4).
(C) When the prepreg is laminated and cured using the form of the inner tank, the prepreg is roughly pasted in advance on the body portion where the flat portion is provided, and the flat portion is obtained by cutting as post-processing after curing. (Not shown).

  Since the FRP inner tank 2 is a part cooled by liquid nitrogen or the like and is subjected to a large temperature change, as described above, the arrangement of the penetration joint to the inner tank 2 is sufficient to prevent vacuum leakage. On the other hand, unlike the inner tank 2, the outer tank 1 is not directly cooled with liquid nitrogen, so it is relatively easy to prevent vacuum leakage at the through-joint portion disposed in the outer tank 1. It is possible to connect from the through joint portion disposed in the plane portion of the tank 2 to the through joint disposed in the body portion of the outer tank 1 through piping and wiring.

(1) Installation of a flat part on a part of the body part of the inner tank Usually, the outer tank 1 and the inner tank 2 are both made of FRP, and the flat part 25 shown in FIG. Can be formed to form the flat portion 25. In this case, in consideration of the mechanical strength of the inner tank, the arrangement of the penetration joint, etc., it is desirable that the flat portion 25 of the inner tank 2 is formed so that the outer surface portion and the inner surface portion form parallel surfaces. Further, it is desirable that the flat portion is molded so that the outer surface portion of the inner tub is formed in a cylindrical shape in the axial direction of the cylinder as shown in FIGS. 3 (A) and 3 (B).
Further, as shown in FIG. 4, the flat portion 29 can be provided by adhering a FRP seat to a part of a conventionally formed FRP cylindrical body. In this case, it is desirable to form a curved surface having the same radius of curvature as the curved surface of the outer surface of the inner tub body in order to increase the adhesive strength of the surface of the seat that contacts the inner tub. In addition, if the material used for the seat is the same as the material used for the inner tub 2, it becomes possible to reduce the difference in linear expansion coefficient between the two materials, and at the time of bonding, It is also preferable for improving the wettability and adhesive strength of the adhesive.
The adhesive used for bonding can be selected from epoxy adhesives, urethane adhesives, unsaturated polyester adhesives and the like that are compatible with the FRP material used.
In consideration of the stable operation of the superconducting rotating device of the present invention for a long period of time, the embodiment shown in the above (a), in which a plane portion is formed integrally with the barrel portion without using an adhesive. Considering compatibility with various stresses such as thermal stress and deterioration of the adhesive, it is possible to more effectively prevent vacuum leakage.

(2) Arrangement of penetration joints on the flat surface When attaching metal joints such as piping for cooling medium and current introduction terminals to the wall surface of the above-mentioned FRP cryostat in a penetrating state, FRP members In general, a male threaded portion of a metal joint is screwed to an internally threaded hole formed through an adhesive (see, for example, Patent Document 4).
As a method for disposing the through joint in the inner tank 2, for example, as shown in FIGS. A male screw member with a flange that protrudes from the female screw hole by screwing a male screw member with a flange to which the metal joint is fixed by being inserted into the female screw hole formed on the FRP container wall surface with an adhesive. A female screw member with a hook is screwed to the part, and the container wall is sandwiched between the hook parts of both members, and then the prepreg is attached and laminated so as to cover the hook part and the container wall surface, and then the prepreg is removed. Fixed by taking care and curing.

  Further, as shown in Patent Document 3, after forming a through hole such as a through hole or a screw hole for arranging a through joint, it can be fixed by an appropriate means. Specifically, for example, the cooling medium piping through joint can be fixed by being attached to the insertion hole of the inner tub 2 and temporarily assembled with an adhesive. , Inserted into the insertion hole of the inner tub 2 and adhered and fixed with an adhesive, or the penetration joint portion embedded in the inner tub 2 is screwed into the male screw hole using a male screw-shaped member Or a method of using an adhesive in combination.

In the case where the through hole joint for cooling medium piping and the through hole joint for current introduction terminal are not provided in the vacuum heat insulating layer on both side plate portions of the cylindrical inner tank 2, the vacuum heat insulating layer is reduced from the conventional 50 mm to about 5 mm. It becomes possible to make it thinner.
On the other hand, although the thickness of the vacuum heat insulating layer in the body portion is somewhat increased, since the thickness does not affect the length of the iron core 13, the rotational output of the superconducting motor is not reduced.
In the superconducting motor shown in FIGS. 2 to 4, for example, if an alternating current is passed through the superconducting coil of the armature of the stator to generate an alternating magnetic field as indicated by the arrow in FIG. Due to this interaction, a rotational force can be applied to the drive shaft 16 as a rotor as a synchronous machine in the same manner as a general motor.

[4] Specific Example of Superconducting Rotating Device of the Present Invention Specific examples of the inner tank of the axial superconducting motor that is the superconducting rotating device of the present invention are shown in FIGS. 2, 3 (A), (B), and 4 (A). , (B) will be described.
The superconducting motor shown in FIG. 2 is provided with six superconducting coils 11 as armature coils on the stator side of a synchronous machine using an AC power supply, as shown in FIGS. 3 and 4, and a rotor on both sides of the stator. The rotor is an axial type superconducting motor (not shown) in which a total of 16 permanent magnets 12 are fixed to each of the rotors as 8 field magnets.

3 (A) and 4 (A) are plan views of the inner tank of the axial type superconducting motor, and FIGS. 3 (B) and 4 (B) are perspective views of the inner tank. 3 (A) and 3 (B), six planar portions 25 are provided in the axial direction on the body portion of the cylindrical inner tub 2 as a whole. In the flat portion 25, a through joint for the cooling medium inlet 5 and the outlet 6 piping, and a through joint for current introduction terminals (U phase 21, V phase 22, W phase 23, and neutral wire 24) are provided. Is laid. By adopting the structure as shown in FIG. 3 and FIG. 4, it is possible to narrow the vacuum heat insulating layers on both side surfaces of the inner and outer tanks to about 5 mm.
As a result, the axial type superconducting motor is disposed between the axial width (referred to as Lc) of the hollow cylindrical superconducting coil 11 which is the armature coil of the motor and the permanent magnets on both sides which are the field. It is possible to make the ratio (Ls / Lc) of the length (referred to as Ls) of the iron core 13 forming the magnetic path in the hollow part of the superconducting coil to be more than 1.0 and 1.3 or less, such a range. Is preferable in that the magnetic flux reaching the permanent magnet from the superconducting coil 11 is effectively suppressed from leaking in the middle.

[5] Features of the superconducting rotating device of the present invention The features of the superconducting rotating device of the present invention will be described with reference to FIGS.
According to FIG. 5, the performance (output) of the motor is determined by the magnitude of the magnetic flux formed by the superconducting coil 11 passing through the permanent magnet 12. Therefore, it is necessary to prevent the magnetic flux reaching the permanent magnet from leaking along the way. The most effective means for preventing this magnetic flux leakage is to reduce the distance between the iron core 13 and the superconducting coil 11 and to bring the length of the iron core 13 close to the axial width of the corresponding superconducting coil 11. By adopting such a structure, the magnetic flux density on the permanent magnet can be increased as shown by the broken line in FIG. 5 (one of the eight points is indicated as part A).

On the other hand, as shown in FIG. 6, the cooling refrigerant inflow / outlet ports 5 and 6 and the current introduction terminals 21 to 24, which are the prior art, are vacuum-insulated on the side portion of the cylindrical upper lid portion, lower bottom plate portion, or flat portion. Although the superconducting coil and the electromagnetic steel sheet are sufficiently close when arranged in the layer part, the length of the iron core is compared with the axial width of the superconducting coil due to the thickness of the vacuum heat insulating layer of the inner tank side plate part. Become longer. As a result, the magnetic flux density on the iron core is relatively low due to magnetic flux leakage, as shown by broken lines in FIG. 6 (one of the eight points is shown as part B).
In general, the number Φ of magnetic flux lines passing through a plane having an area S (m ² ) perpendicular to the magnetic flux lines is represented by Φ = BS. (Here, B is the magnetic flux density, and B = μH (μ is the magnetic permeability, and H is the magnetic field strength (A / m)).

Magnetic flux is generated by passing a current through the superconducting coil. The magnetic flux passes through the armature core and generates electromagnetic force on the end surface (air gap) of the core. The strength of this electromagnetic force is proportional to the product of the number of turns of the coil and the current, and the torque is the electromagnetic force and the number of magnetic flux linkages (the number of magnetic flux linkages is “of the magnetic flux created by the permanent magnet that passes through the iron core, In the case of the winding type, the magnetic flux generated by the field winding is proportional to the one that passes through the armature core). On the other hand, it is known that as the length of the iron core increases, the magnetic resistance increases and the leakage flux increases. Qualitatively, when the leakage flux increases, the number of flux linkages decreases and the torque decreases.
Therefore, in the present invention, the length of the iron core is brought close to the axial width of the superconducting coil, that is, the portion of the iron core around which the coil is not wound is reduced, thereby preventing leakage flux and interlinkage magnetic flux. By preventing the number from decreasing, the torque can be improved.

The cooling medium that can be used in the superconducting rotary device of the present invention is not particularly limited, but since liquid nitrogen can be used, the vacuum heat insulating structure can be simplified. Since superconductivity can make the electric resistance zero, energy efficiency can be increased, and as a result, useless release of heat into the air can be prevented.
In addition, since superconductivity can flow more than 200 times the current, it is possible to reduce the size and weight of the device, and it can be used for motors for marine electric propulsion devices, motors for railways, and other various applications. It is.

It is a cross-sectional conceptual diagram of a superconducting rotating machine, which is a conventional technique. It is a section conceptual diagram of an example of the superconducting rotation equipment of the present invention. It is the top view (A) and perspective view (B) of an example of the inner tank arrange | positioned at the superconducting rotary apparatus of this invention. It is the top view (A) and perspective view (B) of the other example of the inner tank arrange | positioned at the superconducting rotary apparatus of this invention. It is the figure which showed the magnetic flux line in the cross-sectional conceptual diagram of the superconducting motor which is an example of the superconducting rotary apparatus of this invention. It is the figure which showed the magnetic flux line in the cross-sectional conceptual diagram of the superconducting motor which is a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Outer tank 2 Inner tank 3 Vacuum heat insulation layer 4 Cooling medium 5 Cooling medium inflow port 6 Cooling medium outflow port 11 Superconducting coil 12 Permanent magnet 13 Iron core 14 Sub yoke 15 Main yoke 16 Drive shaft 21 U phase 22 V phase 23 W phase 24 Neutral wire 25 Plane portion 26 Penetration joint for cooling medium piping and penetration joint for current introduction terminal 27 Drive shaft arrangement portion 28 Iron core arrangement portion 29 Seat portion 31 Magnetic flux line

Claims (6)

A superconducting coil is disposed around the iron core as an armature on at least the stator side of the rotor and the stator facing each other with a gap between the magnetic pole surfaces in parallel with each other, and the superconducting coil is disposed in the outer tub. And the overall shape of the outer shape is housed in the inner tank of the inner and outer double wall structure tank with the inner tank that is a cylindrical container,
The inner tank contains a cooling medium that is circulated through the outer tank wall and a cooling medium pipe penetration joint disposed on the inner tank wall in order to cool the superconducting coil. It is a superconducting rotating device in which the space between the tank is a vacuum heat insulating layer,
A superconducting rotary device, wherein a through-joint for cooling medium piping and a through-joint for current introduction terminal are disposed in a body portion of the inner tank.   The superconducting rotating device according to claim 1, wherein the inner tank is an inner tank formed of fiber reinforced plastic.   The flat part is provided in at least a part of the trunk part of the inner tank, and the through joint for cooling medium piping and the through joint for current introduction terminal are disposed on the flat part. Superconducting rotating equipment.   The flat part provided in at least one part of the trunk | drum of the said inner tank is a flat part integrally shape | molded with the wall of the inner tank when shape | molding this inner tank. The superconducting rotating equipment described.   The superconducting rotary device according to claim 3, wherein the flat portion provided in at least a part of the body portion of the inner tub is a flat portion provided by bonding a seat made of FRP.   6. The axial superconducting motor according to claim 1, wherein the superconducting rotating device is an axial superconducting motor in which a permanent magnet is fixed as a field on the rotor side, and a superconducting coil is disposed on the stator side as an armature. The superconducting rotary device according to any one of the above.

Images