Power storage device

Abstract

To restrain the reduction in rotation speed caused by heat generation.SOLUTION: A power storage device 100 includes a casing 1, a motor 10 having a motor-side rotation shaft 12 and a motor-side terminal 14 housed in the casing 1, a power generator 20 having a generator-side rotation shaft 22 and a generator-side terminal 24 housed in the casing 1, and a torque converter 30 housed in the casing 1 and coupling the motor-side rotation shaft 12 and the generator-side rotation shaft 22. With power supplied from the outside to the motor-side terminal 14, the motor-side rotation shaft 12 is rotated. With the rotation of the motor-side rotation shaft 12 via the torque converter 30, the generator-side rotation shaft 22 is rotated. A portion of power that is generated in the generator-side terminal 24 with the rotation of the generator-side rotation shaft 22 can be outputted to the outside, and the remaining portion of the power can be supplied to the motor-side terminal 14.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a power storage device that converts externally supplied electric power into rotational kinetic energy of a rotating body and stores the converted power, or converts the rotational kinetic energy of a rotating body into electric power and outputs the power to the outside. [Background technology]

[0002] There is known a flywheel-type power storage device that temporarily converts the energy of electricity, such as a flywheel battery, into the physical energy of rotational motion, stores it, and obtains electricity by generating electricity from the rotational motion when electricity is needed. One example of such a flywheel-type power storage device is a power storage device mounted on a moving object such as an electric vehicle (Patent Document 1). This power storage device includes a motor that can function as a generator, and a rotating body (flywheel) that is attached to the main shaft (rotating drive shaft) of the motor. This motor is a permanent magnet type synchronous motor. The rotating body is a disk-shaped member that expands in a direction perpendicular to the main shaft and has a large moment of inertia.

[0003] In this power storage device, when power (electrical energy) is supplied, the motor increases the rotation speed of the rotor, converting the supplied power into the rotational kinetic energy of the rotor and storing the power in this state. On the other hand, when the stored power is output, the motor functions as a generator, converting the rotational kinetic energy of the rotor into electrical energy and outputting it. At this time, the rotational kinetic energy of the rotor decreases according to the amount of electrical energy output, so the rotation speed decreases.

[0004] In such power storage devices, a rotating body with a large moment of inertia rotates at high speed. Therefore, for example, when a moving body (such as an electric vehicle) equipped with such a power storage device suddenly changes its direction of movement, an extremely large force of inertia (precession) generated by the moment of inertia of the rotating body acts on the moving body, causing the behavior of the moving body to become unstable.

[0005] Therefore, a power storage device has been proposed as described in Patent Document 2. As shown in Figures 8 and 9, this power storage device includes a motor 702 capable of functioning as a generator, a flywheel unit 708 having a rotor 706 attached to a main shaft 704 of the motor 702, and a support member 710 with a gimbal structure that supports the flywheel unit 708 rotatably around two axes (the X-axis and the Y-axis in Figure 8) that are perpendicular to each other on a horizontal plane.

[0006] In this power storage device 700, a gimbal-structured support member 710 supports the flywheel unit 708, allowing the flywheel unit 708 to freely change its attitude relative to the moving body. Therefore, when a moving body equipped with the power storage device 700 suddenly changes its direction of movement, the flywheel unit 708 (rotating body 706 rotating at high speed) changes its attitude relative to the moving body, thereby making it possible to prevent an inertial force (precession) based on the moment of inertia of the flywheel unit 708 (rotating body 706 rotating at high speed) from acting on the moving body.

[0007] However, in a power storage device 700 equipped with a support member 710 having a gimbal structure as described above, a support member 710 having a complex support structure is required, and providing this support member 710 with a complex structure increases the size of the power storage device 700.

[0008] In response to this, a flywheel type power storage device has been proposed that is equipped with a rotor and that, while having a simple structure, is capable of suppressing the inertial force based on the rotation of the rotor acting on a moving body equipped with the power storage device (Patent Document 3). As shown in Fig. 10, this flywheel type power storage device is a flywheel type power storage device 810 that stores supplied power as rotational kinetic energy, and includes a main shaft 812 that extends in a specific direction, a pair of rotors 830, 830 that are attached to the main shaft 812 and can rotate around the main shaft 812, and a drive unit 840 that rotates the rotors 830 in mutually opposite directions while synchronizing the rotation periods around the main shaft 812. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Publication No. 10-285834 [Patent Document 2] JP 2005-65411 A [Patent Document 3] Patent No. 5856039 Summary of the Invention [Problem to be solved by the invention]

[0010] However, there is room for improvement in terms of efficiency in such flywheel type power storage devices.

[0011] The present disclosure has been made in view of the above background, and one of its objects is to provide a power storage device capable of efficiently storing energy.

[0012] The power storage device according to the first embodiment of the present disclosure is a power storage device that stores supplied power as rotational kinetic energy, and includes a housing, a motor having a motor-side rotating shaft and a motor-side terminal housed in the housing, a generator-side rotating shaft and a generator having a generator-side terminal housed in the housing, and a torque converter that connects the motor-side rotating shaft and the generator-side rotating shaft housed in the housing, and the motor-side rotating shaft is rotated by power supplied from the outside to the motor-side terminal, the rotation of the motor-side rotating shaft is rotated by the generator-side rotating shaft via the torque converter, and a part of the power generated at the generator-side terminal by the rotation of the generator-side rotating shaft can be output to the outside, and the other part can be supplied to the motor-side terminal. With the above configuration, when the motor is started, the motor-side rotating shaft is rotated using external power, and the torque is amplified by rotating the generator-side rotating shaft via the torque converter, and when the rotation of the generator-side rotating shaft is stable, a part of the power generated by the generator is supplied to the motor side, thereby reducing the power consumption of the motor.

[0013] In addition, in the power storage device according to the second aspect, in the above-mentioned aspect, the housing is made of a non-magnetic and heat-resistant material. With the above-mentioned configuration, by making the housing out of a non-magnetic material instead of a magnetic material such as metal, it is possible to reduce a situation in which a magnetic force is generated when the motor rotates, and an attractive force acts between the motor and the metallic housing, causing resistance to the rotation.

[0014] Furthermore, in the power storage device according to a third aspect, in any of the above aspects, the housing is made of resin. With the above configuration, by making the housing out of resin instead of metal, it is possible to reduce a situation in which a magnetic force is generated when the motor rotates, and an attractive force acts between the motor and the metal housing, causing resistance to rotation.

[0015] Furthermore, in the power storage device according to a fourth aspect, in any one of the above aspects, the housing has one or more opening windows formed in a part thereof. With the above configuration, it is possible to prevent the rotation speed from decreasing due to heat by increasing the cooling effect through the opening windows formed in the housing.

[0016] Furthermore, in the power storage device according to a fifth aspect, in any one of the above aspects, the open window is formed in the middle of the housing in the longitudinal direction, thereby making it possible to prevent the permanent magnet from being demagnetized by heat.

[0017] Furthermore, in the power storage device according to a sixth aspect, in any one of the above aspects, the motor and the generator use neodymium magnets. With the above configuration, it is possible to prevent the neodymium magnet from losing its magnetic force due to heat by increasing the cooling effect of the housing.

[0018] Furthermore, in the power storage device according to a seventh aspect, in any of the above aspects, the generator has a first winding wound around the generator-side rotating shaft and a second winding thicker than the first winding, and at least a part of the electromotive force generated in the first winding by the rotation of the generator-side rotating shaft can be applied to a motor-side terminal of the motor, and the electromotive force generated in the second winding can be output from the generator-side terminal. With the above configuration, the thin first winding can generate electromotive force faster than the thick second winding, making it possible to quickly start supplying power to the motor side.

[0019] Furthermore, in the power storage device according to an eighth aspect, in any one of the above aspects, the width of the second winding arranged around the generator-side rotating shaft is wider than the width of the first winding arranged around the generator-side rotating shaft. With the above configuration, the electrical energy generated by the generator that is supplied to the outside is increased and the electrical energy that is supplied to the motor side is reduced, thereby improving the output that can be extracted from the generator.

[0020] Furthermore, in the power storage device according to a ninth aspect, in any one of the above aspects, the first winding is closer to the motor than a first winding region arranged around the generator-side rotating shaft, and the second winding is closer to the motor than a second winding region arranged around the generator-side rotating shaft. With the above configuration, the first winding region that generates electromotive force to supply power to the motor side is closer to the motor side, reducing the resistance of the path that supplies power to the motor side, and enabling more efficient power transmission.

[0021] Furthermore, in the power storage device according to a tenth aspect, in any one of the above aspects, the generator-side terminal includes an external output terminal for outputting to the outside the power generated at the generator-side terminal by the rotation of the generator-side rotating shaft, and a motor input terminal for supplying the power to the motor-side terminal, and the motor input terminal is disposed between the motor-side terminal and the external output terminal. With the above configuration, the motor input terminal for supplying power to the motor side is located close to the motor side, making it possible to efficiently supply power to the motor side.

[0022] Furthermore, in the power storage device according to an eleventh aspect, in any one of the above aspects, the housing is of a stationary type.

[0023] Furthermore, in the power storage device according to a twelfth aspect, in any one of the above-mentioned aspects, an air bearing is used for the generator-side rotating shaft, thereby making it possible to prevent wear on the generator-side rotating shaft and improve reliability. [Brief description of the drawings]

[0024] [Figure 1] 1 is a schematic diagram showing a power storage device according to a first embodiment. [Diagram 2] 1 is a schematic diagram showing a power storage device according to a modified example. [Diagram 3] FIG. 11 is a schematic diagram showing a power storage device according to a second embodiment. [Figure 4] FIG. 11 is a schematic diagram showing a power storage device according to a third embodiment. [Diagram 5] FIG. 11 is a schematic diagram showing a power storage device according to a fourth embodiment. [Figure 6] FIG. 4 is a schematic diagram showing an example of an arrangement of permanent magnets with respect to a generator-side rotating shaft. [Figure 7] 10 is a schematic diagram showing another example of the arrangement of permanent magnets with respect to the generator-side rotating shaft. FIG. [Figure 8] FIG. 1 is a diagram showing a schematic configuration of a conventional flywheel type power storage device. [Figure 9] 9 is a vertical cross-sectional view of the flywheel portion taken along the Y-axis direction in FIG. 8. [Figure 10] FIG. 11 is a cross-sectional view of another conventional flywheel type power storage device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Hereinafter, an embodiment of the present disclosure will be described based on the drawings. However, the embodiment shown below is an example for embodying the technical idea of ​​the present disclosure, and the present disclosure does not specify the power storage device as follows. In addition, this specification never specifies the members shown in the claims to the members of the embodiment. In particular, the dimensions, materials, shapes, and relative arrangements of the components described in the embodiment are not intended to limit the scope of the present disclosure to only those, and are merely explanatory examples, unless otherwise specified. Note that the size and positional relationship of the members shown in each drawing may be exaggerated to clarify the explanation. Furthermore, in the following explanation, the same name and symbol indicate the same or similar members, and detailed explanation will be omitted as appropriate. Furthermore, each element constituting the present disclosure may be configured as a form in which multiple elements are composed of the same member and one member serves multiple elements, or conversely, the function of one member can be shared by multiple members. [Embodiment 1]

[0026] A power storage device 100 according to a first embodiment of the present disclosure is shown in a schematic diagram in Fig. 1. The power storage device 100 shown in this figure includes a housing 1, a motor 10, a generator 20, and a torque converter 30. The housing 1 is a hollow member that houses the motor 10, the generator 20, and the torque converter 30 therein. The exterior shape of the housing 1 can be any shape, such as a box shape or a cylindrical shape.

[0027] The housing 1 is preferably made of a non-magnetic material that does not transmit magnetism. By making the housing 1 from a non-magnetic material instead of a magnetic material such as metal, it is possible to reduce the situation in which a magnetic force is generated when the motor 10 rotates, and an attractive force acts between the housing 1 made of metal and the magnetic force, which acts as resistance to the rotation. In other words, by using a housing 1 made of a non-magnetic material, a magnetic brake can be avoided.

[0028] It is also desirable to make the housing 1 out of a heat-resistant material. By making the housing 1 out of a heat-resistant material, it is possible to prevent the permanent magnet from being demagnetized by heat. For example, the housing 1 is made of heat-resistant plastic that can withstand a heat-resistant temperature of 500°C. (Motor 10)

[0029] The motor 10 receives external power from a motor-side terminal 14 to rotate a motor-side rotating shaft 12. The motor-side rotating shaft 12 is connected to a generator-side rotating shaft 22 of a generator 20 via a torque converter 30. A permanent magnet synchronous motor (PMSM) using a permanent magnet in the rotor (field magnet) can be used for the motor 10. This simplifies the structure and reduces the maintenance work. A ferromagnetic material with high magnetic force, such as a neodymium magnet, can be used for the permanent magnet. (torque converter 30)

[0030] The torque converter 30 is a transmission that utilizes the dynamic action of fluid, and generates torque amplification by the rotation difference between the input side and the output side. Oil or the like is used as the granular material, and the speed ratio between the two shafts can be changed steplessly. Such a torque converter 30 is composed of a turbo pump impeller, a turbine impeller, a guide vane, and the like. By connecting the input side of this torque converter 30 to the motor side rotating shaft 12 of the motor 10 and the output side to the generator side rotating shaft 22 of the generator 20, the torque of the motor side rotating shaft 12 can be improved, the load on the motor 10 can be reduced, and the life of the motor 10 can be extended. (Generator 20)

[0031] The generator 20 is connected to the motor-side rotating shaft 12 via a torque converter 30. A permanent magnet synchronous generator using a permanent magnet for the field magnet can be used as the generator 20. The power storage device 100 configured as described above rotates the motor-side rotating shaft 12 of the motor 10 with power supplied from the outside to the motor-side terminals 14. The rotation of the motor-side rotating shaft 12 is transmitted to the generator-side rotating shaft 22 of the generator 20 via the torque converter 30. In this state, the electric energy supplied to the motor 10 is transmitted from the motor-side rotating shaft 12 to the generator-side rotating shaft 22 via the torque converter 30, and is maintained as rotational energy.

[0032] When the supply of power to the motor 10 continues and the rotation of the generator-side rotating shaft 22 becomes stable, an electromotive force is generated by the rotation. A part of the power generated at the generator-side terminal 24 by the rotation of the generator-side rotating shaft 22 can be output to the outside. In other words, it becomes possible to supply a driving electrode to a load such as another electric device connected to the generator-side terminal 24. In other words, a part of the rotational energy stored in the power storage device 100 is taken out as electric energy to the outside.

[0033] On the other hand, another part of the electric power generated at the generator side terminal 24 can be supplied to the motor side terminal 14. This compensates for at least a part of the driving power of the motor 10, and the driving power consumed by the motor 10 can be reduced. In other words, at least partial energy circulation is realized. In particular, by interposing the torque converter 30, the rotational torque of the motor side rotating shaft 12 is amplified and transmitted to the generator side rotating shaft 22, thereby reducing the conversion loss in converting electrical energy to kinetic energy. The use of the torque converter 30 enables more efficient storage and release of electric power than the use of a flywheel. (First winding 27, second winding 28)

[0034] The generator 20 also has a first winding 27 and a second winding 28 wound around the generator-side rotating shaft 22. The second winding 28 is thicker than the first winding 27. In other words, the first winding 27 is made of a thin wire. Then, by the rotation of the generator-side rotating shaft 22, an electromotive force (first output) generated in the first winding 27 can be applied to the motor-side terminal 14 of the motor 10, and an electromotive force (second output) generated in the second winding 28 can be output from the generator-side terminal 24. With this configuration, the thin first winding 27 can generate an electromotive force faster than the thick second winding 28. This is because, at the same rotation speed, a coil of a thin winding generates an electromotive force faster. As a result, after the motor 10 is rotated by an external power source, it is possible to quickly start supplying power to the motor 10, which contributes to driving with low power consumption.

[0035] Furthermore, the first winding width 27W of the first winding 27 arranged around the generator-side rotating shaft 22 is narrower than the second winding width 28W of the second winding 28 arranged around the generator-side rotating shaft 22. In other words, as shown in FIG. 1, the second winding width 28W is wider than the first winding width 27W. With this configuration, it is possible to increase the second output, which is the electrical energy supplied to the outside, of the electrical energy generated by the generator 20. On the other hand, the first output, which is the electrical energy supplied to the motor 10, is suppressed to the minimum necessary to maintain the rotation of the motor 10, thereby suppressing the amount of power consumption that is not taken out to the outside and improving efficiency.

[0036] Furthermore, it is preferable to arrange the first winding region 27R, in which the first winding 27 is arranged around the generator-side rotating shaft 22, closer to the motor 10 than the second winding region 28R, in which the second winding 28 is arranged around the generator-side rotating shaft 22. In the example of FIG. 1, the first winding region 27R is arranged on the right side in the figure, and the second winding region 28R is arranged on the left side, so that the first winding region 27R faces the motor 10. With this configuration, the first winding region 27R, which generates an electromotive force that supplies power to the motor 10 side, is arranged closer to the motor 10 side, reducing the resistance of the path that supplies power to the motor 10 side, and enabling more efficient power transmission. (Generator side terminal 24)

[0037] The generator side terminal 24 includes an external output terminal 26 and a motor input terminal 25. The external output terminal 26 is a terminal for outputting to the outside the electric power generated at the generator side terminal 24 by the rotation of the generator side rotating shaft 22. The motor input terminal 25 is a terminal for supplying the electric power generated at the generator side terminal 24 by the rotation of the generator side rotating shaft 22 to the motor side terminal 14. In the example of FIG. 1, the motor input terminal 25 is disposed between the motor side terminal 14 and the external output terminal 26. By disposing it in this manner, the motor input terminal 25 for supplying electric power to the motor side is disposed close to the motor 10 side, making it possible to efficiently supply electric power to the motor 10 side.

[0038] It is preferable to use neodymium magnets for the motor 10 and the generator 20. This improves the magnetic force and increases the rotational force. However, neodymium magnets have poor temperature characteristics and will demagnetize when heated. For this reason, it is preferable to add a heat dissipation mechanism to the power storage device 100. (heat dissipation mechanism)

[0039] As a specific example of a heat dissipation mechanism, it is preferable that one or more opening windows 2 are formed in a part of the housing 1. This enhances the cooling effect through the opening windows 2 formed in the housing 1, thereby making it possible to prevent a decrease in the rotation speed due to heat.

[0040] It is preferable to provide the opening windows 2 at a plurality of locations. In the example of FIG. 1, the opening windows 2 are opened at a plurality of locations in the middle of the longitudinal direction of the housing 1, and the heat generated inside the housing 1 is released to the outside, thereby preventing heat from building up inside. In particular, when the housing 1 is long and narrow, heat is likely to build up in the middle portion, so by opening the opening windows 2 at a plurality of locations, it is possible to prevent the permanent magnets from being demagnetized due to a rise in temperature, which leads to a decrease in the number of rotations. In addition, a blower fan that forcibly blows cooling air can be provided. Preferably, an opening is formed at the end of the longitudinal direction of the housing 1, and a blower fan is installed to pass cooling air inside along the longitudinal direction.

[0041] The housing 1 can be installed on a mobile object, but is preferably a stationary type. The power storage device 100 can also be used as an emergency power source during a power outage or as a mobile power source. The housing 1 of the power storage device 100 is preferably installed at a height of several meters above the floor. This allows it to be used even during floods or inundation. This is particularly effective when used as an emergency power source or auxiliary power source. For example, it can be installed at a high position, such as in the middle or at the top, by utilizing existing structures such as steel towers for power transmission lines.

[0042] As shown in Fig. 2, a deformation prevention frame FR may be provided around the housing 1. This allows the rigidity to be increased while still using a resin housing 1. When the motor 10 is directly connected to the generator 20 via the torque converter 30, the total weight of the motor 10 itself is lighter than that of the generator 20, so if the motor 10 is not securely fixed, it may rotate. To avoid this, in the example of Fig. 2, cushioning material is placed on the concrete, and an iron plate is placed on top of that and fixed with anchor bolts. [Embodiment 2]

[0043] The generator 20 may also be a double-shaft generator. By rotating the generator-side rotating shaft from each of the two shafts with a motor, the rotational force can be further increased, and the amount of electricity generated and the amount of electricity stored can be increased. Such an example is shown in FIG. 3 as a power storage device 200 according to a second embodiment. In this figure, the same members as those in the above-mentioned first embodiment are given the same reference numerals, and detailed explanations are omitted as appropriate.

[0044] The power storage device 200 shown in FIG. 3 has a double-shaft generator 20B as a generator, and includes a motor 10A arranged on the right side of the double-shaft generator 20B in the figure and a motor 10B arranged on the left side. The motor-side rotating shaft 12A of the motor 10A is connected to the right end of the generator-side rotating shaft 22B of the double-shaft generator 20B via a torque converter 30A. The motor-side rotating shaft 12B of the motor 10B is also connected to the left side of the generator-side rotating shaft 22B via a torque converter 30B. Furthermore, the double-shaft generator 20B has a first winding 27A, which is a thin wire, arranged on the right end of the second winding 28B, which is a thick wire, and a first winding 27B, which is also a thin wire, arranged on the left end of the second winding 28B. The first winding 27A is provided with a motor input terminal 25A that supplies a part of the power to the motor 10A, and the first winding 27B is provided with a motor input terminal 25B that supplies a part of the power to the motor 10B. With this configuration, the two motors rotate the generator side rotating shaft from both ends, increasing the rotational force. When the double-shaft generator 20B is started, more power is required to rotate the two motors 10A, 10B, but once the rotation of the double-shaft generator 20B stabilizes, the amount of power generated and stored can be increased. [Embodiment 3]

[0045] Furthermore, the motor 10 may be a dual-shaft motor. Such an example is shown in FIG. 4 as a power storage device 300 according to the third embodiment. In this figure, the same members as those in the first embodiment and the like are given the same reference numerals, and detailed description thereof is omitted as appropriate. In the power storage device 300 shown in FIG. 4, the motor is a dual-shaft motor 10C, and the left end of the motor-side rotating shaft 12C of the dual-shaft motor 10C is connected to the generator-side rotating shaft 22 of the generator 20 via a torque converter 30, as in FIG. 1 and the like. On the other hand, a flywheel FW is connected to the right end of the motor-side rotating shaft 12C. By connecting the flywheel FW to the other end in this way, the rotation of the motor-side rotating shaft 12C is stabilized by the flywheel effect as a flywheel, and the rotational force transmitted to the generator-side rotating shaft 22 via the torque converter 30 can be increased. [Embodiment 4]

[0046] In the example of FIG. 1 etc., a configuration has been described in which the motor 10, the generator 20, and the torque converter 30 are housed inside one housing 1. However, the present disclosure is not limited to such a configuration in which all components are housed in a common housing, and each component may be housed separately in a plurality of housings. For example, a power storage device 200 according to a fourth embodiment shown in FIG. 5 is composed of a first housing 1a that houses the motor 10 and a second housing 1b that houses the generator 20. In this example, the torque converter 30 is exposed, but the torque converter may be housed in the first housing or the second housing, or may be housed separately in a third housing.

[0047] Air bearings may be used for the generator-side rotating shaft 22 and the motor-side rotating shaft 12. By using a hydrostatic bearing, mechanical friction and wear are not generated as it is non-contact, and rotation with excellent reliability and efficiency is achieved.

[0048] An example of the arrangement of permanent magnets 29 when the generator 20 is a permanent magnet synchronous generator is shown in FIG. 6. As shown in this figure, multiple permanent magnets 29 are arranged at a distance in the axial direction of the generator-side rotating shaft 22. In the figure, when the generator-side rotating shaft 22 rotates and moves from the north pole to the south pole, one free electron is released per rotation. Electrons are moved to the coil by an induced current due to electromagnetic induction. The magnitude of the current here is determined by the distance and thickness of the first winding 27 and second winding 28 that constitute the coil. For example, the current is set at 3,000 to 5,000 revolutions per minute.

[0049] By arranging the multiple permanent magnets 29 in this way, it is possible to increase the power generation efficiency. However, since the multiple permanent magnets 29 are arranged along the axial direction of the generator-side rotating shaft 22, the size of the generator 20 becomes long in the axial direction. As a result, heat tends to be trapped inside the housing 1. Therefore, as described above, the opening window 2 is opened in the middle or the like to ensure heat dissipation.

[0050] Furthermore, the present disclosure is not limited to the configuration in Fig. 6, and only one permanent magnet 29 may be arranged on the generator-side rotating shaft 22 as in a generator 20' shown in Fig. 7. This makes it possible to reduce the size of the generator 20 and prevent heat from building up inside the housing.

[0051] Furthermore, the configuration is not limited to one generator, but may include a plurality of generators. For example, a plurality of generators may be stacked in multiple stages, and a belt may be looped around the generator-side rotating shaft of each generator, which is connected to the motor-side rotating shaft of the motor. [Example]

[0052] The use of the power storage device according to the embodiment will be described. The motor 10 is an ESR1 manufactured by Yaskawa Electric Corporation, the generator 20 is a medium-speed (model number) manufactured by Yaskawa Electric Corporation, and the torque converter 30 is an 8-speed automatic transmission (U880E) for a Toyota Crown (gasoline vehicle). The rated input of the motor 10 is 30 kW / h, and the rated output of the generator 20 is 250 kW / h. In this way, the 30 kW motor 10 rotates the generator-side rotating shaft 22 (iron core) of the 250 kW generator 20 via the torque converter 30. The output at the start of the power storage device is a rated voltage of 100 to 240 W, a frequency of 50 to 60 Hz, and three-phase or single-phase, which can be changed. The input at the start of the power storage device, i.e., the power when starting the motor 10, is 10 kW / h to 30 kW / h. The heat recovery temperature is 85°C.

[0053] The efficiency is assumed to be an overall efficiency of 90%, a power generation efficiency of 100-100,000%, and a heat recovery rate of 45%.

[0054] The first output from the first winding 27 of the generator 20 is 35 kW, and the second output from the second winding 28 is 215 kW. Here, six floodlights (total of about 1320 W) are connected to the external output terminal 26 as external loads, and the lights are turned on 24 hours a day for 30 days. The power consumption on the motor 10 side is 3200 W.

[0055] In addition, the electrical resistance is 0.28wΩ, which is 0.194Ω to 0.206Ω, reducing the overall wiring resistance by 10% to 15%. Furthermore, resistance loss can be calculated by multiplying the square of the current by the resistance, and resistance loss can be reduced by up to 20%. w2=35215k2w1k1=2.33 New resistance = current resistance - (0.2 x current resistance) [Comparative Example]

[0056] Meanwhile, a power storage device according to a comparative example was created and a drive experiment was carried out. A Yaskawa Electric motor (ESR1) was used, and a Yaskawa Electric medium-speed (medium-sized) generator was used. Instead of a torque converter, the motor-side rotating shaft and generator-side rotating shaft were connected by a flywheel from a Crown (gasoline vehicle) 2500cc in-line 4-cylinder turbo engine (U880E model number). The rated input of the motor was 30kW, and the output of the generator was 100kJ / h.

[0057] The primary output from the primary winding of the generator was 35kW, and the secondary output from the secondary winding was 215kW. Six floodlights (total 1320W) were connected to the external output terminal as external loads, and the lights were left on 24 hours a day for 30 days. The power consumption on the motor side was 3200W.

[0058] The electrical resistance was 0.28Ω, which was reduced by 10% to 15% from 0.194Ω to 0.206Ω. According to calculations, the maximum resistance loss can be reduced by 20%. (w2 times = 35215 times k2 times w1 times k1 times = 35215 times x 112 x 1 time = 2.33) [Industrial Applicability]

[0059] The power storage device of the present disclosure stores electrical energy as rotational kinetic energy and can be suitably used as a backup power source or the like that can supply power to other devices.

[0060] In addition, by reducing the drive power of the motor, energy consumption can be reduced. This will reduce the consumption of fossil fuels currently required for power generation, reduce CO2 emissions, and reduce the burden on the environment. As a result, it will be possible to achieve the following of the 17 goals and 169 targets set out in the international goals SDGs (Sustainable Development Goals) adopted at the United Nations Summit in September 2015: "8. Decent work and economic growth", "8.4 By 2030, improve progressively global resource efficiency in consumption and production and endeavour to decouple economic growth from environmental degradation, in accordance with the 10-year framework of programmes on sustainable consumption and production, with developed countries taking the lead." "9. Build inclusive and sustainable industrial and technological infrastructure", "9.4 By 2030, improve infrastructure and industry to ensure sustainability, including by increasing resource efficiency and expanding the adoption of clean and environmentally friendly technologies and industrial processes. All countries will take action in accordance with their respective capabilities", "11. Sustainable cities and towns", "11.6 By 2030, reduce the adverse per capita environmental impact of cities, including by paying special attention to air quality and municipal and other waste management", - The technology contributes to the following targets: "12. Responsible Consumption and Production", "12.4 By 2020, achieve the environmentally sound management of chemicals and all wastes throughout their life cycle, in accordance with agreed international frameworks, and significantly reduce their release to air, water and soil in order to minimize their adverse impacts on human health and the environment", and "12.5 By 2030, substantially reduce waste generation through prevention, reduction, recycling and reuse". [Explanation of symbols]

[0061] 100, 200, 300, 400...Electricity storage device 1... housing; 1a... first housing; 1b... second housing 2...Opening window 10, 10A, 10B...Motor 12, 12A, 12C...Motor side rotating shaft 14...Motor side terminal 20, 20'...Generator 20B…Double-shaft generator 22, 22B... Generator side rotating shaft 24…Generator side terminal 25...Motor input terminal 26...External output terminal 27…first winding; 27W…first winding width; 27R…first winding area 28...second winding; 28W...second winding width; 28R...second winding area 29...Permanent magnet 30, 30A, 30B...Torque converter 700…Electricity storage device 702...Motor 704…Spindle 706...Rotating body 708…Flywheel section 710...Support member 810...Flywheel type power storage device 812…Spindle 830...rotating body 812…Spindle 840…Drive unit FR…Deformation prevention frame FW…Flywheel

Claims

1. A power storage device that stores supplied power as rotational kinetic energy, A housing and a motor housed in the housing and having a motor-side rotating shaft and a motor-side terminal; a generator housed in the housing and having a generator-side rotating shaft and a generator-side terminal; a torque converter housed in the housing and connecting the motor-side rotating shaft and the generator-side rotating shaft; Equipped with The motor-side rotating shaft is rotated by electric power supplied from an external source to the motor-side terminal, and the rotation of the motor-side rotating shaft is used to rotate the generator-side rotating shaft via the torque converter, A power storage device configured so that a portion of the electric power generated at the generator side terminal by rotation of the generator side rotating shaft can be output to an external source, and the other portion can be supplied to the motor side terminal.

2. The power storage device according to claim 1, The power storage device, wherein the housing is made of a non-magnetic, heat-resistant material.

3. The power storage device according to claim 2, The power storage device, wherein the housing is made of resin.

4. The power storage device according to claim 3, The power storage device has one or more opening windows formed in a portion of the housing.

5. The power storage device according to claim 4, The power storage device, wherein the opening window is formed at the middle of the housing in the longitudinal direction.

6. The power storage device according to claim 5, The power storage device, wherein the motor and generator use neodymium magnets.

7. The power storage device according to any one of claims 1 to 6, The generator is wound around the generator-side rotating shaft. A first winding; a second winding thicker than the first winding, By the rotation of the generator side rotating shaft, At least a part of the electromotive force generated in the first winding can be applied to a motor-side terminal of the motor, The power storage device is configured so that the electromotive force generated in the second winding can be output from the generator side terminal.

8. The power storage device according to claim 7, The first winding is arranged around the generator side rotating shaft so as to have a width larger than that of the first winding. The second winding is arranged around the generator side rotating shaft, and the width of the second winding is increased.

9. The power storage device according to claim 7, The first winding is a first winding region arranged around the generator side rotating shaft, The second winding is disposed closer to the motor than a second winding area arranged around the generator-side rotating shaft.

10. The power storage device according to claim 9, The generator side terminal is connected to the generator side terminal through the rotation of the generator side rotating shaft. an external output terminal for outputting to the outside; a motor input terminal for supplying the motor side terminal; Equipped with The power storage device further comprises: the motor input terminal disposed between the motor side terminal and the external output terminal.

11. The power storage device according to any one of claims 1 to 6, The power storage device wherein the housing is of a stationary type.

12. The power storage device according to any one of claims 1 to 6, The power storage device uses an air bearing for the generator-side rotating shaft.

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