JPH08111946A - Superconducting flywheel device - Google Patents

Abstract

PURPOSE: To increase the rotating speed of a flywheel by reducing the centrifugal force applied to permanent magnets constituting a superconducting bearing device. CONSTITUTION: Permanent magnets 41 and 68 are provided on the inside of a flywheel 40 in the diametral direction. The reduction in volume of a bearing caused by the positions of the magnets 41 and 68 which are not on the outside of the diametral direction is compensated by the attracting force of a magnetic bearing composed of permanent magnets 65 and 65.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION A superconducting flywheel device according to the present invention is incorporated into an electric power storage device for converting surplus electric power at night into kinetic energy for storage and for converting this kinetic energy into electric energy for extraction during the daytime. Use it in the default condition.

[0002]

2. Description of the Related Art Although the power consumption at night is smaller than that at daytime, it is technically difficult to finely adjust the power generation at a thermal power plant or a nuclear power plant according to the power consumption. Because of this,
So-called surplus power that cannot be consumed at night is generated. Pumped hydroelectric power plants have been conventionally used as a method for storing such surplus power. A pumped-storage hydroelectric power station has two dam lakes, one with a high height and the other with a low dam, and the surplus power draws water from the lower dam lake to the higher dam lake at night, and during the daytime, the higher dam lake. The water is dropped to the dam lake on the lower side to generate hydroelectric power.

However, in the case of a pumped-storage hydroelectric power plant, since it is an extremely large-scale facility, it cannot be installed in a small-scale business office or a general household, and the topography that can be installed is limited. Even in Japan, it is the current situation that the number of installation locations cannot be increased so much. Therefore, an electric power storage device in which a flywheel having a large moment is fixed to the rotary shaft and a generator / motor is also attached to the rotary shaft has been studied. In the case of this power storage device, by supplying surplus power to the generator / motor at night, the rotary shaft and the flywheel are rotated, the surplus power is converted into kinetic energy, and the rotary motion of the flywheel is performed. To store as. Then, during the daytime, based on this rotational movement, the electric generator / motor is used to generate electric power, and the electric power is taken out and used.

As an electric power storage device using such a flywheel, the present inventors previously invented an electric power storage device using a superconducting bearing device (Japanese Patent Laid-Open No. 6-23347).
No. 9). FIG. 5 shows an electric power storage device according to this prior invention. The atmospheric pressure housing 1 is formed in a cylindrical shape and is arranged in the vertical direction. The upper end of the atmospheric pressure housing 1 is open so that the inside is at atmospheric pressure. The rotary shaft 2 is inserted through the center of the atmospheric pressure housing 1. A cylindrical radial gas bearing 3 is fixed to the lower inner peripheral surface of the atmospheric pressure housing 1. The inner diameter of the radial gas bearing 3 is slightly larger than the outer diameter of the rotary shaft 2. Therefore, the outer peripheral surface of the rotary shaft 2 and the radial gas bearing 3
A minute bearing gap 5 is formed between the inner peripheral surface and the inner peripheral surface.
The bearing clearance 5 is provided in the air supply port 4 during operation of the power storage device.
The compressed air blown into the radial gas bearing 3 from the air blows out to increase the pressure in the bearing gap 5. The load applied in the radial direction of the rotary shaft 2 in this state is supported by the compressed air. The used compressed air flowing out from the bearing gap 5 is discharged through the upper end opening of the atmospheric pressure housing 1 and the exhaust port 17.

On the other hand, a vacuum housing 6 is provided below and adjacent to the atmospheric pressure housing 1, and the vacuum housing 6 and the atmospheric pressure housing 1 form a housing. The inside of the vacuum housing 6 is evacuated by connecting to a suction port of a vacuum pump (not shown). A lower end portion of the atmospheric pressure housing 1 penetrates a circular hole 8 formed in a central portion of a cover plate 7 of the vacuum housing 6 and opens in the vacuum housing 6. A well-known magnetic fluid seal device 9 as a sealing device is provided between the inner peripheral surface of the lower end portion of the atmospheric pressure housing 1 and the outer peripheral surface of the lower portion of the rotary shaft 2 to increase the pressure in the vacuum housing 6. To prevent.

A flywheel 10 is fixed to the lower end of the rotary shaft 2 located inside the vacuum housing 6. The flywheel 10 is made of a metal material having a large specific gravity so as to have a sufficiently large rotational moment. Then, on the lower surface of the flywheel 10, a plurality of (two in the illustrated example) permanent magnets 11, 11 each formed in an annular shape and magnetized in the axial direction (vertical direction in FIG. 1) are concentrically arranged. It is fixed in place.

On the other hand, a cooling jacket 12 constituting a cooling device is provided in the lower half of the inside of the vacuum housing 6 via a heat insulating material 13. The upper opening is the shield plate 14
In the cooling jacket 12, which is closed by the above, superconductors 15 and 15 and a coolant 16 (liquid nitrogen) for cooling the superconductor are provided. This coolant 16
The cooling jacket 12 through the supply / discharge ports 18, 18.
It is sent into the inside, and each superconductor 15, 1 is accompanied with the sending.
Cool 5 Each of these superconductors 15 and 15 is supported and fixed on a support plate 23 in the cooling jacket 12 with its upper surface facing the lower surfaces of the permanent magnets 11 and 11. The superconductors 15 and 15 and the permanent magnets 11 and 11 form a superconducting thrust bearing 22, and mainly support the thrust load of the rotary shaft 2 and the flywheel 10.

Further, the rotor 1 is attached to the upper end of the rotary shaft 2.
9 is fixed, and the stator 20 is fixed to the inner peripheral surface of the upper end portion of the atmospheric pressure housing 1, and the inner peripheral surface of the stator 20 and the outer peripheral surface of the rotor 19 are opposed to each other. The rotor 19 and the stator 20 form a generator / motor 21. The generator / motor 21 rotates the rotating shaft 2 based on the energization of the stator 20 from the outside, and when the rotating shaft 2 is not energized from the outside, the stator 20 generates electric power. To do.

The operation of the power storage device of the prior invention constructed as described above is as follows. When the surplus power is stored at night, etc., the surplus power is supplied to the stator 20 of the generator / motor 21, thereby rotating the rotary shaft 2 and the flywheel 10. At this time, the radial gas bearing 3
Compressed air is sent to the rotor to support the rotating shaft 2 in the radial direction, and the superconductor 1 in the cooling jacket 12 is supported.
Cool 5 and 15. When the superconductors 15 and 15 are cooled and are in a superconducting state, the magnetic flux generated from the permanent magnets 11 and 11 is confined in the respective superconductors 15 and 15. The so-called pinning effect causes the permanent magnets 11 and 11 to become superconductors. 15,
A force acts on 15 to prevent it from moving axially and radially. By this force, thrust force and radial force acting on the rotary shaft 2 and the flywheel 10 are supported. In this way, with the radial gas bearing 3 and the superconducting thrust bearing 22 functioning, the rotary shaft 2 and the flywheel 10 are supported in a floating state. Therefore, the resistance against the rotation of these two members 2 and 10 is extremely small.

The rotational speeds of the rotary shaft 2 and the flywheel 10 gradually increase as the stator 20 is energized. By the action of the radial gas bearing 3 provided between the rotary shaft 2 and the atmospheric pressure housing 1, the rotary shaft 2 and the flywheel 10 can be rotated at high speed, and the electric power is converted into mechanical kinetic energy. It can be stored at.
In addition, the flywheel 10 has a large diameter and a large surface area.
Is provided in the vacuum housing 6, the surface of the flywheel 10 does not rub against air,
The rotational speed of the flywheel 10, which has once increased, will hardly decrease unless electric power is taken out by the generator / motor 21. When the stored energy is taken out and used in the daytime, the stator 20 is used.
To the load (electrical equipment). As a result, electric power is induced in the stator 20 based on the rotational movement of the flywheel 10.

[0011]

In the case of the power storage device according to the previous invention having the above-described structure, it was difficult to store a large amount of energy for the following reasons. That is, in order to increase the energy to be stored, the inertial mass of the flywheel 10 is increased. The rotation speed of the flywheel 10 is increased (increased). Things are needed. In particular, the above is effective because not only does the weight of the flywheel 10 not increase, but also the energy that can be stored increases in proportion to the square of the rotation speed.

However, when the rotational speed of the flywheel 10 is increased, the centrifugal force applied to the annular permanent magnets 11, 11 rotating with the flywheel 10 also increases. This centrifugal force is applied to each of the permanent magnets 11, 11 as a tensile stress extending in the circumferential direction. In particular, a large centrifugal force and accompanying tensile stress are applied to the permanent magnets 11 provided on the diametrically outer side of the flywheel 10. Since the material forming the permanent magnet 11 is brittle, the permanent magnet 11 will be damaged if the centrifugal force becomes excessive. Therefore, in the superconducting flywheel device that constitutes the conventional power storage device, increasing the rotation speed is limited in terms of the strength of the permanent magnets 11 and 11, and the power that can be stored by the power storage device decreases. Will end up. The superconducting flywheel device of the present invention was invented in view of such circumstances.

[0013]

The superconducting flywheel device of the present invention, like the superconducting flywheel device incorporated in the conventional power storage device described above, has a fixed housing and a vertical direction inside the housing. And a flywheel fixed to the rotary shaft concentrically with the rotary shaft, and a concentric position about the rotary shaft on at least one of the upper surface and the lower surface of the flywheel. A permanent magnet fixed to the housing, a superconductor fixed to a part of the housing and facing the permanent magnet, and a cooling device provided in the housing to cool the superconductor.

In particular, in the superconducting flywheel device of the present invention, the flywheel has an upper surface having a ferromagnetic portion at a portion radially outward of the permanent magnet, and a portion of the lower surface of the housing has a strong ferromagnetic portion. A magnet is fixed to the portion facing the magnetic body.

[0015]

In the case of the superconducting flywheel device of the present invention configured as described above, the weight of the flywheel and the rotating shaft is the superconducting bearing composed of the permanent magnet and the superconductor,
It is supported by a ferromagnetic part and a magnetic bearing composed of a magnet. Therefore, even if the weight of the flywheel is increased in order to sufficiently increase the inertial mass of the flywheel, the flywheel and the rotary shaft can be sufficiently levitated.

Further, among the constituent members of each of these bearings, the permanent magnets constituting the superconducting bearings are fixed to the ferromagnetic material portion of the flywheel and the portion radially inward of the magnets fixed to the housing. The centrifugal force acting on the permanent magnet due to the rotation of the flywheel is small. Therefore, even if the rotational speed of the flywheel is increased to increase the energy to be stored, the permanent magnet will not be damaged. Further, a large centrifugal force acts on the ferromagnetic material forming the magnetic bearing, but the strength of the ferromagnetic material is much higher than the strength of the permanent magnet, so even if the rotational speed is increased. , The part of this ferromagnet is not damaged.

[0017]

1 to 3 show an embodiment of the present invention. For example, the housing 25 is fixed in the recessed hole 24 formed by digging down the ground. This housing 25 has a bottom 2
6 and the intermediate portion 27 and the upper portion 28 are connected so as to be stacked. The bottom portion 26 is formed by forming a cylindrical standing wall 30 on a portion of the disc-shaped bottom plate 29 near the outer periphery of the upper surface. or,
The intermediate portion 27 has a circular ring shape as a whole and has an upper surface formed into a conical convex surface. Further, the upper portion 28 has an annular connecting cylinder 31 coupled to the central portion of the upper surface of the intermediate portion 27, a cylindrical motor housing 32 connected in series above the connecting cylinder 31, and the motor housing. And a lid plate 33 that closes the upper end opening of 32. Although illustration is omitted, each member constituting the housing 25 is firmly connected by a bolt or the like. Further, the inside of the housing 25 is entirely in a vacuum atmosphere.

A rotating shaft 34 is provided inside the housing 25.
Are arranged in the vertical direction. The rotary shaft 34 has a large-diameter portion 35 at the lower end, an intermediate-diameter portion 36 at the middle, and a small-diameter portion 37 at the upper end, which are continuous through stepped portions. Further, an upper tapered surface 38 having a conical convex shape for forming a centering device to be described later is formed at the upper end of the small diameter portion 37, and a small diameter pivot shaft portion 39 is provided above the upper tapered surface 38. Is protruding.

A flywheel 40 is fixed to the lower end of the rotary shaft 34 concentrically with the rotary shaft 34.
The flywheel 40 is arranged inside the standing wall 30. A plurality of permanent magnets 41, 41 each formed in an annular shape are formed on the diametrically inner portion of the upper surface of the flywheel 40 made of a metal such as iron having a large specific gravity to obtain a large inertial mass. Are supported and fixed via a ring-shaped holder 42. Each of the permanent magnets 41, 41 is magnetized in the axial direction (vertical direction in FIGS. 1 and 3), and is arranged in a concentric position about the rotary shaft 34.

A plurality of superconductors 43, 43 are provided in the central portion of the lower surface of the intermediate portion 27, and a plurality of permanent magnets 41,
The first superconducting bearing device 70 is configured so as to be fixed in a state of facing 41 and utilize the pinning force in the pulling direction. In addition, the superconductors 43, 43 are the permanent magnets 4 described above.
Although it is preferable to form an annular shape like Nos. 1 and 41, it is difficult to actually make an annular shape, and even if it is made, the cost will increase. For this reason, in the illustrated embodiment, the superconductors 43, 43, each having a convex cross section and formed in a disk shape,
The concave portion 4 formed on the lower surface of the cooling jacket 44 described below.
5 and 45, and by the restraining plate 46, the recess 4
We are trying to prevent it from slipping out from 5, 45.

The cooling device for cooling the superconductors 43, 43 includes the cooling jacket 44.
The cooling jacket 44 is made of a metal having a good heat transfer property such as copper or aluminum, and is hollow and is formed into an annular shape as a whole. The cooling jacket 44 is fitted into a concave portion 47 formed in the central portion of the lower surface of the intermediate portion 27 via heat insulating materials 48, 48, and the concave portion 4 is formed by an annular holding plate 49.
I am trying to prevent it from coming off from 7. The heat insulating materials 48a and 48a are also sandwiched between the upper surface of the pressing plate 49 and the upper surfaces of the intermediate portion 27 and the cooling jacket 44. In such a cooling jacket 44, a coolant such as liquid nitrogen can be freely supplied and discharged through supply and discharge passages 50, 50 provided so as to penetrate the intermediate portion 27.

Further, a second superconducting bearing device 71 utilizing a pinning force in the repulsive direction is provided between the lower surface of the flywheel 40 and the upper surface of the bottom plate 29, and the bearing capacity in the thrust direction ( The weight that can be supported) has been increased.
That is, a circular recess 72 is formed in the center of the lower surface of the flywheel 40, and a plurality of permanent magnets 68, 68 each formed in an annular shape are formed in the recess 72 in the circular holder 7.
It is supported and fixed via 3. Each of these permanent magnets 68,
Each of the magnets 68 is magnetized in the axial direction (vertical direction in FIGS. 1 and 3), and is arranged in a concentric position about the rotary shaft 34.

On the other hand, in the central portion of the upper surface of the bottom plate 29, a plurality of superconductors 69, 69 are provided, and a plurality of the permanent magnets 68,
It is fixed in a state of facing 68. The superconductors 69, 69 are also similar to the superconductors 43, 43 described above.
Recesses 75 formed on the upper surface of the cooling jacket 74, which are formed in a disk shape with a convex cross section,
75 is fitted inside, and further by the restraining plate 76, the recess 75,
We are trying to prevent it from coming off from 75.

The cooling jacket 74 is made of a metal having a good heat conductivity in the shape of a hollow disk. The cooling jacket 74 is fitted into a recess 77 formed in the center of the upper surface of the bottom plate 29 via heat insulating materials 78, 78, and an annular holding plate 79 is used to prevent the cooling jacket 74 from coming off from the recess 77. There is. Also between the lower surface of the holding plate 79 and the upper surfaces of the bottom plate 29 and the cooling jacket 74, the heat insulating materials 78a, 7a
8a is clamped. In such a cooling jacket 74, a coolant such as liquid nitrogen can be supplied / discharged through supply / discharge passages 80, 80 provided through the bottom portion 26.

The superconductor 43 is formed on the lower surface of the intermediate portion 27.
A plurality of permanent magnets 65, 65 are fixed to the outer peripheral portion. Each of these permanent magnets 65, 65 is formed in a disk shape with a convex cross-section like the superconductors 43, 43 described above. Then, it is fitted in the recesses 66, 66 formed on the lower surface of the intermediate portion 27, and the retaining plate 67 is used to prevent the recesses 66, 66 from coming off. The permanent magnets 65, 65 are also arranged in concentric circles centered on the rotary shaft 34.

On the other hand, the upper surface of the flywheel 40 is a portion radially outward of the permanent magnets 41 and 68, and the portion facing the plurality of permanent magnets 65 and 65 is a portion of a ferromagnetic material such as iron. Therefore, a force in the levitation direction is applied to the flywheel 40 by the magnetic attraction force acting between the ferromagnetic parts and the permanent magnets 65, 65. However, this magnetic attraction force is not sufficient for the flywheel 40 to float by itself. This is because the ferromagnetic material and the permanent magnet 6 are based on the magnetic attraction force.
This is to prevent close contact with Nos. 5 and 65. That is, the flywheel 40 includes the ferromagnetic material and the permanent magnet 6
Not only the supporting force of the magnetic bearing composed of 5 and 65,
The supporting force by the first superconducting bearing device 70 and the supporting force by the second superconducting bearing device 71 described above are summed up, and they are supported in the floating state for the first time.

In other words, the magnetic bearing that merely applies a force in the levitation direction functions as an auxiliary bearing that supports the weight of the flywheel 40, and acts as a resistance against the flywheel 40 moving up and down due to the pinning force. The second superconducting bearing device 70, 71 is the flywheel 40.
Functions as a main bearing that keeps the levitation state. The flywheel 40 does not necessarily have to be entirely made of a ferromagnetic material. At least the permanent magnets 65, 65
The upper surface of the flywheel 40 facing each other may be covered with a ferromagnetic material. Therefore, it is also possible to fix the iron plate only to this upper surface portion and to make the other portions with another material aiming at higher speed rotation. For example, the flywheel 40 is wholly or partially (for example, the outer peripheral edge portion) made of a reinforced fiber-plastic composite (CFRP) portion 40a.

A generator / motor 21 is installed between the outer peripheral surface of the lower portion of the small diameter portion 37 and the inner peripheral surface of the lower half portion of the motor housing 32. This generator / motor 21 having functions as an electric motor and a generator includes a stator 20 fixed to an inner peripheral surface of a lower half portion of the motor housing 32, and a stator 20 at a lower portion of the small diameter portion 37.
And a rotor 19 fixed to a portion opposed to.

The rotating shaft 34 and the flywheel 40 are provided between the outer peripheral surface of the intermediate portion of the rotating shaft 34 and the upper end portion of the intermediate portion 27 and the inner peripheral surface of the connecting cylinder 31.
An elevating device 51 for elevating and lowering is provided. For this purpose, a cylinder space 53 is provided, which is surrounded on three sides by the step portion 52 formed on the inner peripheral surface of the upper end portion of the intermediate portion 27 and the lower surface of the connecting cylinder 31, and the inner peripheral opening of the cylinder space 53 is provided with a lifting sleeve 54. It is oil-tightly closed by. Further, the piston portion 55 formed on the outer peripheral surface of the intermediate portion of the elevating sleeve 54.
The outer peripheral edge of the above is in oil-tight contact with the inner peripheral surface of the stepped portion 52. Therefore, the cylinder space 53 has the piston portion 5
5 divides into an upper chamber 56 and a lower chamber 57. Pressure oil can be freely supplied to and discharged from each of the chambers 56 and 57 through supply and discharge ports (not shown), and the elevating sleeve 54 is moved up and down in accordance with the supply and discharge.

A lifting sleeve 58 is provided inside the elevating sleeve 54 and a pair of upper and lower deep groove type (or angular type) ball bearings 59, 59 (or the rotating shaft 34 and the flywheel are particularly heavy). Is a tapered roller bearing)
Thus, only the rotation of the elevating sleeve 54 is rotatably supported. A conical concave lower centering surface 60 is formed on the inner peripheral surface of the upper end portion of the lifting sleeve 58. A centering ring 61 is fitted and fixed to the lower half of the middle diameter portion 36 at the intermediate portion of the rotary shaft 34. A lower tapered surface 62 having a conical convex surface is formed on the lower surface of the centering ring 61. The lower taper surface 62 comes into close contact with the lower centering surface 60 as the lifting sleeve 58 rises.

On the other hand, inside the cover plate 33, a receiving sleeve 63 is supported by a pair of upper and lower deep groove type ball bearings 59, 59 so as to be rotatable only with respect to the cover plate 33. A conical concave upper surface centering surface 64 is formed on the inner peripheral surface of the lower end portion of the receiving sleeve 63.
And the upper tapered surface 38 are opposed to each other. The upper tapered surface 38 is provided with the upper centering surface 64 as the rotary shaft 34 is moved up as the lifting sleeve 58 is moved up.
Close to.

Further, a control type magnetic bearing is provided between the inner peripheral surface of the housing 25 and the outer peripheral surface of the rotary shaft 34 to support the rotary shaft 34 and the flywheel 40 in the radial direction. There is. That is, magnetic bodies 81 and 81 are externally fitted and fixed to the outer peripheral surface of the intermediate portion of the large diameter portion 35 and the outer peripheral surface of the upper end portion of the small diameter portion 37, respectively, and the inner peripheral surface of the intermediate portion 27 and the motor housing 32. Electromagnets 82, 82 are respectively fixed to the inner peripheral surfaces of the upper part of the. Each of these electromagnets 82, 82 is divided into a plurality of (for example, four) portions in the circumferential direction, and energization to each portion is controlled based on a signal from a controller (not shown). or,
A displacement sensor (not shown) is provided between the rotary shaft 34 and the housing 25, and energization to each part of each of the electromagnets 82, 82 is controlled based on a detection signal of the displacement sensor.

The operation of the power storage device of the present invention configured as described above is as follows. During operation of the power storage device, the rotating shaft 34 and the flywheel 40 are supported in a floating state. For this purpose, first, the cooling jackets 44, 7
In the upper chamber 56, pressure oil is sent to the lower chamber 57 constituting the lifting device 51 before the cooling device is operated and the cooling devices are not operated to bring the superconductors 43 and 69 into the superconducting state. Drain the oil. As a result, the lifting sleeve 54 provided with the piston portion 55 and the ball bearing 5
The lifting sleeve 58 supported by the elevating sleeve 54 is raised by 9, 59, and the lower centering surface 60 and the lower tapered surface 62 come into close contact with each other. The lifting sleeve 5
8 continues to rise even after the two surfaces 60, 62 are in close contact with each other. Therefore, the rotary shaft 34 rises, and the upper taper surface 38 formed on the upper end of the rotary shaft 34 and the upper centering surface 64 come into close contact with each other. In this way, the lower centering surface 60
And the lower taper surface 62, the upper taper surface 38 and the upper centering surface 64 come into close contact with each other, and as a result, the centering is configured to include the members forming these surfaces 60, 62, 38, 64. The rotating shaft 34 is centered by the device. As a result of centering, the rotary shaft 34 and the flywheel 4
The 0 peripheral surface will not come into contact with the mating surface as it rotates.

Further, in order to center the rotary shaft 34 in this manner, when the rotary shaft 34 is raised, the permanent magnets 41, 41 fixed to the upper surface of the flywheel 40 which rises together with the rotary shaft 34. And the superconductors 43, 4 fixed to the lower surface of the intermediate portion 27 via a cooling jacket 44.
3 and 3 come into contact with or come close to each other. In this state, a large amount of magnetic flux (above each permanent magnet 4
Almost all of the magnetic flux emitted from 1, 41 enters. Further, as the flywheel 40 rises, the permanent magnets 68, 68 fixed to the lower surface of the flywheel 40 and the plurality of superconductors 69, 69 fixed to the upper surface of the bottom plate 29 separate from each other. Then, with the two members 68, 69 separated from each other in this way, the magnetic flux emitted from the permanent magnets 68, 68 enters the superconductors 69, 69.

Therefore, with the rotating shaft 34 and the flywheel 40 being raised, a coolant is fed into the cooling jackets 44, 74, and the superconducting materials are fixedly attached to the cooling jackets 44, 70. Body 43,
69 is brought into a superconducting state. As a result, each of the above-mentioned permanent magnets 4
Many magnetic fluxes from 1, 68 are generated in each of the superconductors 43, 69.
Pinned inside (the magnetic flux cannot be displaced in its flow direction).

When the superconductors 43 and 69 are completely in the superconducting state, the pressure oil is sent to the upper chamber 56 and the oil in the lower chamber 57 is discharged at the same time. As a result,
The lifting sleeve 58 descends, and the upward force applied to the rotary shaft 34 is released. As a result,
The rotating shaft 34 and the flywheel 40 tend to descend due to their own weight. In this state, the attractive force of the magnetic bearing composed of the permanent magnet 65 and the ferromagnetic body, and the pinning force between the superconductors 43 and 69 and the permanent magnets 41 and 68 act. The pinning force of the rotary shaft 34
And, the displacement of the flywheel 40 is prevented.

First, the permanent magnets 41, 41 on the upper surface of the flywheel 40 and the superconductor 43 on the lower surface of the cooling jacket 44,
A large pinning force across the pulling direction acts between the pin 43 and the pin 43. When the flywheel 40 rises, the upper surfaces of the permanent magnets 41, 41 and the superconductors 43, 43 are in contact with or in close proximity to each other.
Almost all of the magnetic flux emitted from 41 is the above superconductors 43, 4
3 and is pinned in the superconductors 43, 43. These permanent magnets 41, 41 and the superconductor 4
The pinning force in the pulling direction acting between the permanent magnets 3 and 43 becomes the maximum when the permanent magnets 41, 41 and the superconductors 43, 43 try to separate from the contact state.
Therefore, the pinning force in the pulling direction acting between the permanent magnets 41, 41 and the superconductors 43, 43 constituting the superconducting flywheel device is sufficiently large.
As a result, the rotary shaft 34 and the flywheel 40 are rotatably supported in a floating state and with sufficiently large bearing rigidity in the thrust direction. That is, even when the flywheel 40 is slightly lowered, a large pinning force acts, so that the bearing rigidity in the thrust direction increases.

Moreover, the permanent magnets 68, 68 fixed to the lower surface of the flywheel 40 and the cooling jacket 74 are
A pinning force in the tension direction acts between the superconductors 69, 69 fixed to the upper surface of the. Although the pinning force in the tension direction is smaller than the pinning force in the pulling direction, it prevents the flywheel 40 from descending in a state of being added to the pinning force in the pulling direction. Therefore, the bearing capacity of the flywheel 40 and the rotary shaft 34 in the thrust direction becomes larger, so that the flywheel 40 having a large inertial mass and a large weight is supported.

In the case of the superconducting flywheel device of the present invention, the permanent magnets 41, 68 constituting the first and second superconducting bearing devices 70, 71 are installed inside the flywheel 40 in the diametrically inner direction. It is provided only on the part. Therefore, the bearing capacity of each of these superconducting bearing devices 70 and 71 is
The permanent magnets 41 and 68 are smaller than those provided even in the diametrically outer portion, and the flywheel 40, which is heavy, cannot be supported as it is. However, in the case of the present invention, a force in the levitation direction is applied to the flywheel 40 by a magnetic bearing composed of the permanent magnets 65, 65 and a ferromagnetic portion on the upper surface of the flywheel 40. Therefore, the flywheel 40 can be sufficiently supported in the floating state.

In this way, when the rotary shaft 34 and the flywheel 40 are held in a floating state and excess power is stored at night, excess power is supplied to the stator 20 of the generator / motor 21. Then, the rotary shaft 34 and the flywheel 40 are rotated. At this time, the electromagnets 82, 82 are appropriately energized to prevent the rotary shaft 34 and the flywheel 40 from being displaced (vibrated) in the radial direction.

Permanent magnets 41 and 68 and superconductors 43 and 69
The support rigidity in the thrust direction due to is sufficiently large, and
These permanent magnets 41 provided in the diametrically inner portion,
The centrifugal force applied to 68 does not become so great. Therefore, the rotary shaft 34 and the flywheel 40 can be rotated at high speed, and a sufficient power storage capacity can be exhibited. When the stored energy is taken out and used in the daytime or the like, the generator / motor 21 generates electric power based on the rotational movement of the flywheel 40, and the electric power is taken out from the conductor wire connected to the stator 20.

Incidentally, between the inner peripheral surface of the lifting sleeve 58 and the outer peripheral surface of the intermediate diameter portion 36, and the receiving sleeve 63.
The thickness dimension of the gap between the inner peripheral surface and the outer peripheral surface of the pivot portion 39 is smaller than any of the thickness dimensions of the clearance existing in the next portion. Magnetic bodies 81, 81 provided in pairs one above the other
Between the outer peripheral surface and the inner peripheral surfaces of the electromagnets 82, 82. Between the outer peripheral surface of the rotor 19 and the inner peripheral surface of the stator 20 that form the generator / motor 21.

Therefore, even when a strong force is applied to the rotary shaft 34 and the flywheel 40 in the radial direction due to an earthquake or the like, a gap is secured in the above-mentioned portion, and the peripheral surfaces existing in these portions are secured. Do not rub against each other. That is, in this case, each of the ball bearings 59, 59 functions as a backup bearing to support the radial load applied to the rotary shaft 34 and allow the rotary shaft 34 to rotate. Therefore, it is possible to prevent damage to the members existing in the above portion. Since the inside of the housing 25 is vacuum, there is little resistance to the rotation of the flywheel 40.

Further, the magnetic bodies 81, 81 and the electromagnet 82,
In order to save electric power consumption by the control type magnetic bearing configured by 82 and 82, for preventing radial displacement between the outer peripheral surface of the large diameter portion 35 and the inner peripheral surface of the intermediate portion 27. ,
A third superconducting bearing device 87 can also be provided. For this purpose, as shown in FIG. 4, a plurality of annular permanent magnets 83, 83 are provided on the outer peripheral surface of the large diameter portion 35 that constitutes the lower portion of the rotary shaft 34.
Is fixed by external fitting. Each of these permanent magnets 83, 83 is magnetized in the axial direction. Further, the cooling jacket 44a fixed to the lower surface of the intermediate portion 27 has an L-shaped cross section, and the permanent magnets 83, 83 are formed on the inner peripheral surface of the cooling jacket 44a.
A plurality of superconductors 84, 84 are fixed to the portion facing. The superconductors 84, 84 are also the above-mentioned superconductor 4
Similar to Nos. 3 and 43, disc-shaped ones each having a convex cross section are fitted into the recesses 85 and 85 formed on the inner peripheral surface of the cooling jacket 44a, and further extended in the circumferential direction. The holding plate 86 divided into a plurality of
I am trying to prevent it from coming off from 85. However, these superconductors 84, 84 are curved according to the shape of the inner peripheral surface of the cooling jacket 44a.

When such a third superconducting bearing device 87 is provided, the superconductor 84 on the inner peripheral surface of the cooling jacket 44a comes out from the permanent magnets 83, 83 fixed to the outer peripheral surface of the large diameter portion 35. The magnetic flux pinned to the shafts 84, 84 exerts a pinning force in the diametrical direction of the rotary shaft 34.
The pinning force prevents the rotary shaft 34 from being displaced in the radial direction.

When such a third superconducting bearing device 87 is provided, it is not necessary to always energize the control type magnetic bearing. However, when a radial load exceeding the bearing rigidity of the third superconducting bearing device 87 is applied for some reason such as an earthquake and the rotating shaft 34 vibrates in the radial direction, the magnetic bodies 81, 81 and the electromagnet 82, The control type magnetic bearing by 82 operates to suppress this vibration. However,
This controlled magnetic bearing is normally not energized to reduce power consumption.

Further, in the illustrated embodiment, in order to support the weight of the flywheel 40, the first and second superconducting bearing devices 70 and 71 are provided. The other superconducting bearing device may be omitted if the weight can be supported by the cooperation of the magnets 65, 65 and the magnetic bearing formed of the ferromagnetic material in the upper portion of the flywheel 40. In this case, it is preferable to omit the second superconducting bearing device 71 having low bearing rigidity. If the first superconducting bearing device 70 having high bearing rigidity is provided, the flywheel 40 can be rotated at an extremely high speed even if the second superconducting bearing device 71 is omitted.

[0048]

The superconducting flywheel device of the present invention comprises:
Although constructed and operated as described above, the centrifugal force applied to the permanent magnets constituting the superconducting bearing device can be reduced, the permanent magnets are less likely to be damaged, and the rotational speed of the flywheel can be increased. As a result, the kinetic energy that can be stored in the flywheel is made sufficiently large, and the power that can be stored in, for example, a power storage device incorporating a superconducting flywheel device is increased, so that the power can be effectively used.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing the overall configuration of an embodiment of the present invention.

FIG. 2 is an enlarged view of a portion A in FIG.

FIG. 3 is an enlarged view of the B section.

FIG. 4 is a cross-sectional view corresponding to the upper left portion of FIG. 3, showing a state of installation of a superconducting bearing device that supports a radial load.

FIG. 5 is a vertical cross-sectional view of a prior invention device.

[Explanation of symbols]

 1 Atmospheric Pressure Housing 2 Rotating Shaft 3 Radial Gas Bearing 4 Air Supply Port 5 Bearing Gap 6 Vacuum Housing 7 Lid Plate 8 Circular Hole 9 Magnetic Fluid Sealing Device 10 Flywheel 11 Permanent Magnet 12 Cooling Jacket 13 Insulation Material 14 Shield Plate 15 Superconductor 16 Coolant 17 Exhaust Port 18 Supply / Discharge Port 19 Rotor 20 Stator 21 Generator / Motor 22 Superconducting Thrust Bearing 23 Support Plate 24 Recessed Hole 25 Housing 26 Bottom 27 Intermediate Part 28 Upper 29 Bottom Plate 30 Standing Wall 31 Connecting Cylinder 32 Motor Housing 33 Lid Plate 34 Rotating shaft 35 Large diameter part 36 Medium diameter part 37 Small diameter part 38 Upper taper surface 39 Pivot part 40 Flywheel 40a Reinforced fiber plastic composite part 41 Permanent magnet 42 Holder 43 Superconductor 44, 44a Cooling jacket 45 Recess 46 Board 47 Recesses 48, 48a Heat insulating material 49 Suppression plate 50 Supply / discharge path 51 Elevating device 52 Step portion 53 Cylinder space 54 Elevating sleeve 55 Piston part 56 Upper chamber 57 Lower chamber 58 Lifting sleeve 59 Ball bearing 60 Lower centering surface 61 Centering ring 62 lower taper surface 63 receiving sleeve 64 upper centering surface 65 permanent magnet 66 concave portion 67 restraining plate 68 permanent magnet 69 superconductor 70 first superconducting bearing device 71 second superconducting bearing device 72 concave portion 73 holder 74 cooling jacket 75 concave portion 76 Suppression Plate 77 Recesses 78, 78a Heat Insulating Material 79 Suppression Plate 80 Supply / Discharge Path 81 Magnetic Material 82 Electromagnet 83 Permanent Magnet 84 Superconductor 85 Recess 86 Suppression Plate 87 Third Superconducting Bearing Device

Claims (1)

[Claims] 1. A fixed housing, a rotary shaft vertically arranged inside the housing, a flywheel concentric with the rotary shaft and fixed to the rotary shaft, and an upper surface and a lower surface of the flywheel. A permanent magnet fixed at a concentric position about the rotation axis on at least one of the surfaces, a superconductor fixed to a part of the housing and facing the permanent magnet, and provided in the housing. In a superconducting flywheel device provided with a cooling device for cooling a lever superconductor, a top surface of the flywheel has a ferromagnetic portion at a portion radially outward of the permanent magnet, and a part of the housing. A superconducting flywheel device characterized in that a magnet is fixed to a portion of the lower surface facing the ferromagnetic body.