JPH04282050A - Electric power storage device - Google Patents

Abstract

PURPOSE:To prevent the energy loss by supporting plural flywheels forming the inertial mass part of a rotor, by superconductors, and disposing concentric circle like permanent magnets at the lower face of the flywheels, thus supporting the rotor floatingly by magnetic resiliency. CONSTITUTION:A rotor 12 is formed of an armature 13, an inertial mass part 15 provided with flywheels 26, and a rotary shaft 12a. Flywheels 26 are supported by superconductor pellets 23 provided at annular flanges 22 protrusively provided on the inner wall surface of a storage room 16, and each flywheel is provided at its lower face with ring like permanent magnets 27 in such a way as to be spaced opposedly from the pellets 23. Or disc like magnets 28 are also disposed at the vertical end parts of the rotary shaft 12a. The rotor 12 is thereby supported in the state of floating in a casing 11 by magnetic resiliency.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power storage device that converts surplus electrical energy such as late-night electricity into kinetic energy generated by rotation of a flywheel and stores the kinetic energy.

0002

2. Description of the Related Art Recently, research has been conducted on power storage devices that convert electrical energy into kinetic energy generated by rotation of a flywheel and store the kinetic energy.

FIG. 9 illustrates the concept of this power storage device, in which a rotor 3 is housed inside a casing 2 of the power storage device 1. As shown in FIG. An armature 4 and a flywheel 5 are provided on the rotating shaft 3a of the rotor 3. The upper and lower ends of the rotating shaft 3a are held by bearings 5a and 5b provided on the upper and lower walls of the casing 2. A coil device 6 facing the armature 4 is located near the side surface of the armature 4.
is installed, and when there is surplus electricity such as at night,
By applying magnetic force to the armature 4 from this coil device 6, the rotor 3 is rotated, and when surplus power is exhausted,
The coil device 6 is stopped. When the application of magnetic force from the coil device 6 is stopped, the rotation of the rotor 3 is maintained by the inertial force of the flywheel 5. When extracting electrical energy, an induced current is generated in the coil device due to the rotation of the armature 4, so a load is connected to the power extraction terminal of the coil device 6 to extract electric power.

0004

By the way, in the case of a power storage device using such a flywheel, in order to increase the power storage capacity to a practical scale, it is necessary to increase the radius of the rotating flywheel 5 and increase the rotation speed. need to be increased. However, with a shape like the conventional power storage device 1,
When the flywheel 5 is made large and rotated at high speed, a strong centrifugal force is generated, and the strength of the flywheel 5 is lost to the centrifugal force, resulting in damage.

[0005] Furthermore, with the conventional bearings 5a and 5b, there is a large loss of energy per day due to friction, and about 30% of the stored energy is lost, so there is a problem that electric power cannot be stored efficiently. left behind.

[0006]

OBJECTS OF THE INVENTION The present invention has focused on these problems, and an object of the present invention is to provide a power storage device that has extremely low energy loss and is capable of storing a large amount of power.

[0007]

[Means for Solving the Problem] In order to achieve the above object, the power storage device according to claims 1 to 6 of the present invention comprises:
In order to prevent damage to the flywheel due to centrifugal force and to realize a large-capacity power storage device, small-diameter flywheels are connected in multiple stages to form an inertial mass section, and each flywheel is supported within the casing. It is characterized by forming a plurality of flanges.

[0008] In claim 2, in order to increase the rigidity of the bearing and to prevent vibration caused by non-uniform magnetic force in the circumferential direction of the ring-shaped permanent magnet, an area that does not exceed the equivalent radius of the second moment of inertia is provided. It is characterized by being widely used to increase the total repulsive force.

Furthermore, in the power storage device according to claims 3 to 6 of the present invention, in order to reduce friction loss due to the bearing, the bearing itself is a bearing using a superconductor, and in order to reduce windage loss of the rotor, , at least an inertial mass portion of the rotor is disposed in a vacuum space.

[0010] Furthermore, in the power storage device according to claims 4 to 6 of the present invention, in order to reduce the iron loss of the armature, the inertial mass part and the armature part are connected by a clutch so that they can be connected and disconnected. Features.

[0011]

[Operation] According to the power storage device according to claims 1 to 6 of the present invention, since the lower surface of each flywheel is supported by the bearing of the flange, the load per unit area of the bearing can be reduced, and the overall weight is large. flywheel can be levitated. Furthermore, since the small-diameter flywheel is formed in multiple stages, stress due to centrifugal force during high-speed rotation can be reduced relative to the strength of the flywheel, and breakage of the flywheel during high-speed rotation can be prevented. Furthermore, since the flange and flywheel are separated by the repulsive force of the superconductor, energy loss due to friction can be reduced to almost zero.

0012

DESCRIPTION OF THE PREFERRED EMBODIMENTS A power storage device according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a power storage device 10 of this embodiment. This power storage device 10 is designed so that its power storage capacity is 2Mwh, and the casing 11 is installed in a concrete pit C in the ground with a shock absorber S such as an air spring.
It is arranged through. The casing 11 includes a first storage chamber 14 that stores the armature 13 of the rotor 12, and a first storage chamber 14 that stores the armature 13 of the rotor 12.
A second storage chamber 16 containing an inertial mass section 15 is provided.

Both the first storage chamber 14 and the second storage chamber 15 are formed in a cylindrical shape, and a cooling chamber 18 for storing liquid nitrogen 17 is formed in a cylindrical shape within the side wall of the second storage chamber 16. It is formed. The first storage chamber 14 is provided with a coil section 19 consisting of a stator coil and a stator stem. The coil unit 19 is capable of energizing the stator coil to generate magnetic force from the stator stem to rotate the armature 13, and also to rotate the armature 13 when the stator coil is de-energized and the armature 13 is rotating. An induced current flows through the coil 13, and this induced current can be extracted as electric power. In this embodiment, storage room 1
4 and a storage chamber 16 are in communication, and a pipe 21 connected to a vacuum pump 20 is connected to the storage chamber 16.
The air in the storage chambers 14 and 16 is sucked out to create a vacuum. This is to reduce air resistance when the rotor 12 rotates.

[0015] Annular flanges 22 are provided protruding from the inner wall surface of the storage chamber 16. The inside of each flange 22 is a space 22a that continues to the cooling chamber 18, and the liquid nitrogen 17 can occupy this space 22a. A superconductor pellet 23 is provided on the upper surface of each flange 22. The pellets 23 are cylindrical with a diameter of 39 mm and a thickness of 20 mm, and 2000 pellets are provided in a ring shape per stage of the flywheel 26. The bottom of the pellet 23 faces the space 22a and is cooled by contacting the liquid nitrogen. For the pellet 23, an oxide superconductor having a pinning effect that captures magnetic flux lines is used.

[0016] To obtain the pellets 23, for example, the MPMG method (Melt-Power
A method for forming yttrium/barium/copper oxides by methods such as the Melt-Growth method (IST
EC Journal Vol. 3 No. 3 1990) may be referred to.

In this embodiment, pellets 24 are provided on the bottom wall of the storage chamber 16 to face the lower end of the rotating shaft 12a of the rotor 12 at a distance.
It is designed to be cooled by Furthermore, storage room 1
Similarly, pellets 25 made of a high temperature superconducting material are disposed on the ceiling of No. 4, spaced apart from and facing the upper end of the rotating shaft 12a.

The rotor 12 is composed of an armature 13, an inertial mass section 15, and a rotating shaft 12a. The inertial mass section 15 includes three flywheels 26. This flywheel 26... has a diameter of 4 m and a thickness of 0.1 m.
In this embodiment, the number of stages is three. The material of the flywheels 26 is non-magnetic high-strength steel or 80 kg class high-tensile steel, and the total weight of the inertial mass section 15 when configured in three stages is 30 tons (that is, the weight of one flywheel 26 is 10 tons). ), the rotation speed of the inertial mass section 15 is 4500 r
Let it be pm.

Each flywheel 26 is positioned above the flange 22 so as to be supported by the pellet 23 of the flange 22. A ring-shaped permanent magnet 27 is provided on the lower surface of each flywheel 26 and faces the pellet 23 at a distance (see FIGS. 2 and 3). The outer diameters of the ring-shaped permanent magnets 27 are 1.6 m and 1.6 m from the side closest to the rotating shaft 12a, respectively.
7m, 1.8m, 1.9m, 2.0m, and the outer diameter is 6.
It is less than 6%. Ring-shaped permanent magnet 2
7 are arranged concentrically with a width of 25 mm and a thickness of 25 mm. In this embodiment, disk-shaped magnets 28 are also provided at the upper and lower ends of the rotating shaft 12a, respectively, and the rotor 12
The entire structure is suspended and supported within the casing 11. The magnetic flux lines generated in the vertical direction from the permanent magnet 27 on the lower surface of the flywheel 26 are rejected by the pellet 23 below the flywheel 26 and are subjected to magnetic repulsion, thereby lifting the flywheel 26 from the flange 22. Although not shown in this embodiment as an auxiliary means, a ring-shaped magnet 27 is similarly provided on the upper surface of the flywheel 26.
By installing superconducting pellets on the lower surface of each flange 22, the flywheel can also be held by the hanging effect of the pellets 23.

In the above embodiment, the casing 11 was constructed so that the storage chamber 14 and the storage chamber 16 communicated with each other.
The storage chamber 14 and the storage chamber 16 are defined by horizontal partition walls, and superconducting pellets are provided on the upper and lower walls of the storage chamber 14 to serve as bearings, and the rotation axis of the armature 13 and the rotation axis of the inertial mass section 15 are connected. The upper and lower ends of the rotating shaft of the armature 13 are separated into the storage chamber 1.
The upper and lower ends of the rotating shaft of the inertial mass section 15 are spaced apart and opposed to the bearing pellets made of superconducting material on the upper and lower walls of the storage chamber 16, respectively. Furthermore, the lower end of the rotating shaft of the armature 13 and the upper end of the rotating shaft of the inertial mass section 15 are configured to be able to be connected and disconnected by a disconnector such as a clutch (an electromagnetic clutch or a magnetic clutch may be used). You may do so.

FIGS. 4 to 6 show a state in which such a clutch is constituted by, for example, a magnetic clutch.
A coupling plate 29 is provided at the lower end of the rotating shaft 13a of the armature 13, a coupling plate 30 is provided at the upper end of the rotating shaft 15a of the inertial mass section 15, and a circular Plate-shaped electromagnets 31 are arranged radially around the rotation center line. Permanent magnets 32 are arranged radially around the rotation center line on the surface of the coupling plate 30 facing the coupling plate 29. Note that an amorphous alloy is used as the iron core material of the electromagnet 31.

In the case shown in FIGS. 4 to 6, the electromagnet 31
When the armature 13 and the permanent magnet 32 are connected to each other by controlling the energization by a sliding contact (not shown) in the storage chamber 14 and exciting the electromagnet 31 when the inertial mass section 15 is driven to couple the electromagnet 31 and the permanent magnet 32, the armature 13 and the inertial mass section 15 are When the armature 13 and the inertial mass section 15 are rotated together and the electromagnet 31 is de-energized, the armature 13 and the inertial mass section 15 are separated, and the inertial mass section 15 can continue to rotate without receiving rotational resistance from the armature 13. Then, when the storage chambers 14 and 16 are brought into a vacuum state by their respective vacuum pumps, the armature 1
3 and the rotation of the inertial mass section 15, there is no air resistance, so the ability of the inertial mass section 15 to sustain rotation is further improved.

FIGS. 7 and 8 show the rotating shaft 12a of the rotor 12.
This is an improved configuration of the radial direction bearing shown in FIG. 3, and in the one shown in FIG. 3, a ring-shaped permanent magnet 40 is provided on the circumferential surface of the rotating shaft 12a. On the other hand, four stems 41 extend from the inner wall of the casing 11 toward the permanent magnet 40 of the rotating shaft 12a so that the distance from the rotating shaft 12a can be adjusted. A superconductor 42 is provided on the tip end surface of each stem 41, and the rotating shaft 12a is held by the magnetic repulsion of the superconductor 42.

[0024]

[Effect] Since the power storage device according to claims 1 to 6 of the present invention is configured as described above, the rotor can be rotated without contact and without resistance, and energy loss due to friction can be reduced to almost zero. can be reduced.

[0025] Therefore, by completing a practical-scale, high-efficiency power system using this device, surplus power such as late-night power can be efficiently stored and used, thereby reducing power demand due to seasonal and time-of-day fluctuations. It can improve the tendency of the load factor of power equipment to decline, and has great effects in stabilizing the supply of electricity and maintaining electricity rates.

[0026] Furthermore, in the case of the power storage device according to claim 3,
The magnetic repulsion of the superconductor and permanent magnet is also applied to the radial bearing that holds the rotating shaft of the rotor, so the frictional resistance acting on the rotating shaft when the rotor rotates becomes zero, further preventing energy loss.

Furthermore, in the case of the power storage device according to claim 4, if the rotational axis of the armature and the rotational axis of the inertial mass section are separated after the rotor has rotated, the rotational energy of the armature is transferred to the drive coil. Since the inertial mass part is not affected even if it is consumed by the restraining magnetic force from the status stem, it is possible to further reduce the loss of stored energy.

[Brief explanation of the drawing]

FIG. 1 An explanatory diagram showing the configuration of a power storage device according to an embodiment of the present invention.

[Figure 2] Explanatory diagram showing the arrangement relationship between the flywheel and superconducting pellets in Figure 1

[Figure 3] Back view of the flywheel in Figure 2

[Figure 4]
An explanatory diagram when a magnetic clutch is provided on the rotating shaft of the power storage device in Figure 1

[Figure 5] Explanatory diagram showing the electromagnet installed on the rotating shaft on the armature side in Figure 4

[Figure 6] Explanatory diagram of the arrangement of permanent magnets on the rotating shaft on the inertial mass part side in Figure 4

[Figure 7] Explanatory diagram showing a modification of the radial bearing of the power storage device in Figure 1

[Figure 8] Partially enlarged plan view of the radial bearing in Figure 8

[Figure 9] Structural conceptual diagram of a conventional power storage device using a rotating body

[Explanation of symbols]

10...Power storage device 11...Casing 12...Rotor 13...armature 14...First storage room 15...Inertia mass part 16...Second storage room 17...Liquid nitrogen 18...Cooling room 19...Coil part 20...Vacuum pump 22...Flange 23...Pellets 25...Pellets 26...Flywheel 27...Large-diameter ring-shaped permanent magnet 28...Small diameter ring-shaped permanent magnet 29...Binding board 30...Binding board 31...Electromagnet 32...Permanent magnet 40...Radially magnetized ring-shaped permanent magnet 41...Stem 42...Superconductor

Claims (6)

[Claims] Claim 1: A rotor in a casing is rotatably driven by electric energy, and includes an electric power generator capable of reconverting the electric energy as necessary, and after the supply of drive energy is stopped to the rotation shaft of the armature of the rotor. A power storage device including an inertial mass section that stores energy by rotating the rotor due to inertia, wherein the inertial mass section is formed by forming a multi-stage disc-shaped flywheel. Power storage device. 2. The power storage device according to claim 1, wherein a ring-shaped permanent magnet is provided within a circle corresponding to 66% of the radius of the lower surface of each flywheel of the inertial mass section to generate vertical magnetic flux lines; Bearing flanges are formed in the casing and are spaced apart and opposed to the upper and lower surfaces of each flywheel, and portions of these flanges that face the permanent magnet have magnetic repulsion that can levitate the multi-stage flywheel. A power storage device characterized by being provided with a superconductor. 3. The power storage device according to claim 2, wherein the casing is provided with a storage chamber in which the inertial mass is defined from the armature and stored in a vacuum state, and the ceiling of the storage chamber is provided with the A radial bearing section for holding the rotating shaft portion between the armature and the inertial mass section is provided, the flange section is formed on the inner wall of this storage chamber, and the inside of the wall forming this storage chamber is filled with liquid nitrogen. A power storage device characterized by forming a chamber. 4. The power storage device according to claim 2 or 3, wherein the rotating shaft of the rotor is configured to be separated into a rotating shaft portion on the armature side and a rotating shaft portion of the inertial mass portion,
A power storage device characterized in that both rotating shaft portions are located on the same axis, and a clutch is installed at opposing ends of both. 5. The power storage device according to claim 4, wherein a ring-shaped magnet magnetized radially in the radial direction of the flywheel is attached to the rotating shaft of the inertial mass part, and the ring-shaped magnet is placed inside the casing. A power storage device comprising a stem extending toward the rotor, and a superconductor cooled and disposed on a surface of the stem facing the ring-shaped magnet to serve as a radial bearing for the rotor. 6. The power storage device according to claim 4, wherein the clutch is constituted by a magnetic clutch, and the magnetic clutch is constituted by a pair of parallel plane plates facing each other, one of the plane plates facing the rotating mass part. The other flat plate is installed at the end of the rotating shaft on the armature side, and a radial permanent magnet is placed on the top surface of one flat plate, and a radial electromagnet is placed on the bottom surface of the other flat plate. A power storage device characterized in that: