JP2017208894A - Flywheel device for electric power storage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To minimize iron loss generated in a stator of a motor-generator at a time of delivering and receiving no energy and to maximize cost performance of a flywheel device for electric power storage by separating energy storage means and energy delivering and receiving means.SOLUTION: A rotor having a permanent magnet for a flywheel for determining an amount of storage energy and a stator for determining power generation output are configured as a separate unit whose mutual position can be arbitrarily set by a traverse unit. Since no stator function is required at a time of delivering and receiving no energy, loss by electromagnetic induction can be minimized by isolating it from a rotor unit. When an amount of storage energy needs to be increased, only the rotor unit can be added. When power generation output needs to be increased, only a stator unit can be added.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an improvement of a flywheel device for power storage.

Patent Document 1 is a conventional example of a power storage flywheel device.
The FW rotor 2 is supported by bearings 3 and 3 at the upper and lower portions of the rotating shaft 1 and the thrust force of the FW rotor is supported by the magnetic repulsive force generated between the permanent magnet 7 on the lower surface of the FW rotor and the superconducting magnet 8 that opposes it. Has been.

  The upper surface of the FW rotor 2 is provided with a rotor 4 of a motor generator (which serves as both a motor and a generator), and a stator 5 is provided above the rotor 4 so that a gap with the rotor can be adjusted. The reactive current due to the field weakening current is suppressed by adjusting the gap accordingly. In addition, the inside of the FW device is evacuated to reduce windage loss due to the rotation of the FW rotor 2.

JP 2002-247822 A

  However, this apparatus has the following problems. Although the stator of the motor generator has a mechanism for adjusting the axial gap with the rotor, the amount of movement is limited by the bearing and the FW support that fixes the bearing. The gap cannot be expanded to the extent that the induction is weakened, and energy loss occurs due to iron loss when energy is not transferred.

In addition, since the FW rotor size that determines the amount of stored energy and the motor generator that determines the power generation output are integrated, it cannot efficiently respond to each demand change. In other words, even if only the amount of stored energy was to be doubled, it was necessary to double the power generation output by adding the same equipment, or to discard the current equipment and newly install a device that only doubles the FW rotor. .
Furthermore, when checking the motor generator, it was necessary to discard the stored energy for safety.

Accordingly, an object of the present invention is to realize the minimization of loss accompanying energy conversion regardless of whether energy is transferred or not.
It is another object of the present invention to provide a flywheel device for power storage that meets the needs at a minimum cost by adopting a configuration in which the stored energy amount and the power generation output can be individually selected and changed.

  Specifically, a decompression vessel, a flywheel supported rotatably in the decompression vessel, a permanent magnet disposed on the outer surface of the flywheel in rotational symmetry with respect to the rotation center, and a phase angle of the permanent magnet are detected. A rotor unit comprising phase detection means, a stator unit constituted by a plurality of coils wound corresponding to the arrangement of the permanent magnets, and phase angle information of the permanent magnets from the phase detection means A motor generator control unit that energizes a plurality of coils of the stator unit to rotate the rotor unit, or returns the electric power generated in the coils of the stator unit to the power source according to the rotation of the rotor unit, and the relative relationship between the rotor unit and the stator unit It consists of a traverse unit that sets the position, and the first relative position that the traverse unit sets is The rotational center of the rotating magnetic field generated by the application of the current voltage is made substantially coincident with the rotational center of the permanent magnet, and the permanent magnet and the coil are brought close to each other through the wall of the decompression vessel, and the second relative position is , Characterized in that at least two directions including the gap interval direction are changed except for the flywheel rotation direction within 6 degrees of freedom in the direction away from the permanent magnet and the coil with respect to the first relative position. An object of the present invention is to provide a power storage flywheel device.

In addition, there is a plurality of at least one of the rotor unit and the stator unit.
Further, at least the decompression vessel side plate on the side where the permanent magnet is arranged is made of a material having low conductivity.
In addition, an autonomous distributed rolling bearing is used as a means for rotatably supporting the flywheel of the rotor unit.

Further, the bearing is characterized in that the inner ring is fitted to a fixed shaft passing through the center of the decompression vessel and the outer ring is rotated.
In addition, a greasing hole communicating with the inner ring of the bearing is formed in the fixed shaft, and the other end of the greasing hole is opened to the outside of the decompression container through a sealing valve.

  According to the present invention, since the rotor as the energy storage body and the stator as the energy transfer body are separated as separate units, the rotating magnetic field generated by the rotation of the rotor unit is generated in the stator unit by moving both units away when energy is not transferred. The intensity of the electromagnetic induction exerted can be reduced to suppress the occurrence of iron loss, and at the same time, the excitation of the motor generator control unit to the stator unit can be stopped.

  In addition, by constructing a rotor unit that is an energy storage body and a stator unit that is an energy transfer body in quantities according to demand fluctuations, a flywheel device for power storage with a necessary and sufficient amount of stored power and a maximum output is constructed. As a result, the overall cost reduction and the standardization and cost reduction of the rotor unit and stator unit can be promoted.

  Moreover, the iron loss which a pressure reduction container generate | occur | produces by the electromagnetic induction by a permanent magnet can be suppressed by making the permanent magnet side of a pressure reduction container into a material with low electrical conductivity.

  Furthermore, by making the bearing an autonomous distributed rolling bearing, it is possible to suppress sliding friction inside the bearing and energy loss due to consumption of the lubricant due to friction.

  In addition, the inner ring of the bearing is fitted to a fixed shaft that passes through the center of the decompression vessel, and the outer ring is rotated. Cost reduction of the rotor unit is progressing.

  In addition, a grease supply hole communicating with the inner ring of the bearing is formed in the fixed shaft, and the other end of the grease supply hole is opened to the outside of the decompression container through a sealing valve. It becomes unnecessary and the cost is reduced by simplifying the opening / closing mechanism of the rotor unit.

The Example of the flywheel apparatus for electric power storage of this invention. Details of the rotor unit of FIG. The 2nd Example of the flywheel apparatus for electric power storage of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. However, the drawings are for explanation only and do not limit the descriptive scope of the present invention.

FIG. 1 shows an embodiment of a flywheel device for power storage according to the present invention, and FIG. 2 shows its rotor unit.
The shaft 16 communicates with the through hole 11a of the cylindrical flywheel 11, and autonomously distributed rolling bearings 15 are incorporated at both ends. Both ends of the shaft 16 protrude from the inner ring inner diameter of the autonomously distributed rolling bearing 15, and this portion is fitted into the recess 10 c formed in the side plates 10 a, 10 b of the cylindrical decompression container 10, thereby making the flywheel 11 the decompression container. 10 is rotatably supported. At the same time, the shaft 16 also has an action against the atmospheric pressure received by the both side plates when the decompression vessel 10 is decompressed.

A ring-shaped short-circuit core 14 is fixed to one end face of the flywheel 11, and a Halbach arrayed multi-pole permanent magnet 12 having a high magnetic flux density in the direction of the axis 16 is fixed thereon. The permanent magnet side plate 10a of the decompression vessel is made of a resin material having low conductivity.
One end of the shaft 16 is provided with a check valve 17, and an oil supply hole 18 communicates with the vicinity of the autonomously distributed rolling bearings at both ends. The side plate 10a of the decompression container 10 has a hole 19 for opening the check valve from the outside and supplying lubricant to the autonomously distributed rolling bearing. Airtightness in the decompression container is ensured by pressing the permanent magnet side plate 10a against one end of the shaft 16 by atmospheric pressure during decompression.

  The phase detection means 13 outputs the angle phase of the flywheel to the motor generator control unit 3 by radio means as needed. There are four rotor units 1 in two rows, the right row being 1Ra and 1Rb, and the left row being 1La and 1Lb. The plurality of coils 21 of the stator unit 2 are arranged corresponding to the arrangement of the permanent magnets 12 of the rotor unit 1.

  The motor generator control unit 3 synchronizes the rotor unit and the stator unit as a motor when energy is stored in the flywheel, and functions as a generator when energy is released, in synchronization with the rotor phase obtained from the phase detection means 13. The energization switching to 21 is performed. The traverse unit 4 includes a telescopic shaft 41 and a reversing shaft 42, and a stator unit is set at the tip.

  Next, the operation will be described. The first relative position A shown in FIG. 1 makes the center of the rotating magnetic field generated by applying an alternating voltage to the coil of the stator unit 2 substantially coincide with the center of rotation of the permanent magnet 12 of the rotor unit 1Ra, and This is a position where electromagnetic induction is strengthened by reducing the gap between the magnet 21 and the permanent magnet 12. When accumulating energy from this position, the motor generator control unit 3 accelerates the flywheel 11 of the rotor unit 1Ra by increasing the excitation frequency to the stator unit 2 in accordance with the supplied power.

When the predetermined energy is accumulated by the speed increase, the traverse unit 4 moves to the second relative position B (a fixed position when energy is not transferred). That is, the telescopic shaft 41 of the traverse unit is shrunk (operation a in the figure), the gap between the stator unit 2 and the rotor unit 1Ra is enlarged to weaken the electromagnetic induction, and then reversed until the permanent magnet surface of the stator unit becomes the upper surface. The shaft 42 is rotated 90 ° (middle of b in the figure) to minimize electromagnetic induction of the coil 21 and the permanent magnet 12.
Since the magnetic flux density in the Halbach array increases the magnetic flux density in the axial direction, minimization of electromagnetic induction only by the gap widening operation leads to enlargement of the telescopic shaft 41 and its occupied space. Electromagnetic induction is effectively minimized by making the turning surface parallel to the direction of the magnetic field lines of the permanent magnet. This minimizes the iron loss due to the rotating magnetic field produced by the rotor unit and the speed reduction of the rotor unit. In this state, the motor generator control unit 3 can stop the generation of the rotating magnetic field of the stator unit.

When energy storage is continued, the traverse unit 4 further rotates the reversing shaft 42 by 90 °, and then the motor generator control unit 3 determines the frequency of the voltage applied to the coil 21 based on the information of the phase detection means 13 of the rotor unit 1La. While adjusting the phase and synchronizing with the permanent magnet of the rotor unit 1La, the telescopic shaft 41 of the traverse unit 4 is extended (operation c in the figure), and the gap between the stator unit 2 and the rotor unit 1La is reduced to increase the electromagnetic induction and supply. The flywheel speed of the rotor unit 1La is increased according to a command from the motor generator control unit 3 in accordance with the electric power to be generated.
The rotor unit 1Ra is moved upward in the figure by a conveyor (not shown) until the stored energy is released, and the rotor unit 1Rb from which the energy is released stands by at this position.

In the case of releasing energy, the traverse unit brings the stator unit close to the energy-stored rotor unit and strengthens electromagnetic induction, so that the coil of the stator unit generates electric power by the rotating magnetic field created by the permanent magnet.
Further, when temporary energy release during energy storage is performed, the rotor unit is not switched, and the circuit is switched by the motor generator control unit 3 (the stator unit is switched from the motor to the generator). This is an operation of a known short-cycle power storage flywheel device.

  When entering the standby state, the permanent magnet 12 is demagnetized by means such as passing a large current at the timing of demagnetizing the permanent magnet to the coil 21 of the stator unit or irradiating the permanent magnet 12 with a laser from the outside. Thus, it is possible to further reduce the iron loss during standby. In this case, the magnetic force of the permanent magnet 12 is recovered by passing a large current having a timing and polarity for magnetizing the permanent magnet in the coil 21 at the start of energy transfer.

  In addition, during the traverse operation, the stator unit is not coupled with the rotor unit, so energy cannot be transferred. A function of switching the circuit to (not shown in the figure) can be added to the motor generator control unit 3.

Since the stator unit 2 that does not include the flywheel 11 that is an energy storage body is small and light, the electromagnetic induction target can be switched from the rotor unit 1Ra to 1La in a relatively short time. Therefore, the small power storage unit may be smaller than the rotor unit.
On the other hand, replacement of the rotor unit 1 by a conveyor (not shown in the figure) requires a long time because it includes a heavy flywheel, but when replacing the rotor unit 1Ra to 1Rb, the accumulated energy of the rotor unit 1La on the opposite side is reduced. A general-purpose conveyor can be applied to this replacement device because it only needs to be completed before it reaches zero.

  FIG. 3 shows a second embodiment of the power storage flywheel device of the present invention. Differences from FIG. 1 are listed below. The flywheel 11 of the rotor unit 1 has a rotation axis in the vertical direction. Ten rotor units are arranged around the traverse unit 4, but normally the second relative position B (a fixed position when energy is not transferred) is an empty space, and the stator unit when energy is not transferred is usually here. Located in. The traverse unit has two arms 4Ra and 4Rb, each of which has telescopic shafts 4Za and 4Zb. A stator unit 2a that maximizes efficiency in the generator and a stator unit 2b that maximizes efficiency in the electric motor are mounted at the distal end of the telescopic shaft in electromagnetic induction with the rotor unit 1.

  According to this configuration, the stator unit 2a that maximizes the efficiency of the generator is used during normal energy release, and the stator unit 2b that maximizes the efficiency of the electric motor is used during normal energy storage. As a result, the loss in energy transfer can be kept low. Further, when it is desired to increase the amount of energy exchanged per hour, these two types of stator units can be used simultaneously for energy storage or energy release.

Moreover, the rated output of two stator units does not need to be the same. For example, when it is desired to change the discharge output sharply, only the stator unit 2a optimized as a generator can be made large. In that case, the small stator unit 2b for the electric motor can be used for low electric power to increase the efficiency of the rotor unit drive.
Further, as a countermeasure against an urgent increase in the amount of energy released per hour, a spare stator unit 2 can be electromagnetically induced with the rotor unit by a forklift (not shown) or the like separately from the existing traverse unit 4. The forklift at that time is the traverse unit 4.

  The present invention relates to a structure of a flywheel device for power storage.

1 Rotor unit 2 Stator unit 3 Motor generator control unit 4 Traverse unit

Claims (6)

  A decompression vessel, a flywheel rotatably supported in the decompression vessel, a permanent magnet disposed on the outer surface of the flywheel in rotational symmetry with respect to a rotation center, and a phase angle of the permanent magnet are detected. A rotor unit comprising phase detection means, a stator unit constituted by a plurality of coils wound corresponding to the arrangement of the permanent magnets, and phase angle information of the permanent magnets from the phase detection means A motor generator control unit for energizing a plurality of coils of the stator unit to rotate the rotor unit, or returning electric power generated in the coils of the stator unit to the power source according to the rotation of the rotor unit; and the rotor unit and It consists of a traverse unit that sets the relative position of the stator unit, and the first relative that the traverse unit sets The rotation center of the rotating magnetic field generated by applying an AC voltage to the coil is substantially coincident with the rotation center of the permanent magnet, and the permanent magnet and the coil are brought close to each other through the wall of the decompression vessel. The second relative position is a gap in the direction away from the permanent magnet and the coil with respect to the first relative position, except for the flywheel rotation direction within 6 degrees of freedom of space. A flywheel device for power storage, wherein at least two directions including the interval direction are changed.   The power storage flywheel device according to claim 1, wherein at least one of the rotor unit and the stator unit is plural.   The flywheel device for power storage according to claim 1, wherein at least a surface of the decompression vessel on which the permanent magnet is disposed is made of a material having low electrical conductivity.   2. The power storage flywheel device according to claim 1, wherein an autonomous decentralized rolling bearing is used as means for rotatably supporting the flywheel of the rotor unit.   2. The power storage flywheel device according to claim 1, wherein the bearing is fitted to a fixed shaft that passes the inner ring through the center of the decompression vessel and rotates the outer ring.   2. The grease supply hole communicating with the inner ring of the bearing is formed in the fixed shaft, and the other end of the grease supply hole is opened to the outside of the decompression vessel through a sealing valve. Flywheel device for power storage.

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