CN115360849A

CN115360849A - Flywheel energy storage system

Info

Publication number: CN115360849A
Application number: CN202211294602.3A
Authority: CN
Inventors: 苏森; 王志强; 陈胜林; 韩坤; 卜庆瑞
Original assignee: Huachi Kinetic Energy Beijing Technology Co ltd
Current assignee: Huachi Kinetic Energy Beijing Technology Co ltd
Priority date: 2022-10-21
Filing date: 2022-10-21
Publication date: 2022-11-18
Anticipated expiration: 2042-10-21
Also published as: CN115360849B

Abstract

The invention discloses a flywheel energy storage system which comprises a shell, a flywheel, a sealing assembly, a stator and a rotor, wherein the shell is provided with an inner cavity; the flywheel is rotatably assembled in the inner cavity; the sealing assembly is arranged between the shell and the flywheel to realize rotary sealing between the shell and the flywheel, and divides the inner cavity into a cooling cavity and a vacuum cavity, and the vacuum cavity is suitable for reducing the rotation resistance of the flywheel; the stator and the rotor are arranged in the cooling cavity, a cooling medium is suitable for being introduced into the cooling cavity to cool the stator and the rotor, the stator is arranged in the shell, and the rotor is arranged on the flywheel and can rotate under the action of the stator. The flywheel energy storage system provided by the embodiment of the invention has the advantage of good heat dissipation effect.

Description

Flywheel energy storage system

Technical Field

The invention relates to the technical field of power storage, in particular to a flywheel energy storage system.

Background

The energy storage flywheel drives the flywheel to rotate at a high speed through the motor, electric energy is temporarily converted into kinetic energy of the flywheel, the electric energy is stored in the form of the kinetic energy of the flywheel, and the flywheel drives the generator to generate electricity when needed.

Disclosure of Invention

The present invention is based on the discovery and recognition by the inventors of the following facts and problems:

in order to reduce the resistance between the flywheel and air, the flywheel energy storage system in the related art places the flywheel in a vacuum environment, and the heat dissipation effect of the part of the motor on the flywheel under the vacuum condition is poor, so that faults are easily caused.

The present invention is directed to solving, at least in part, one of the technical problems in the related art. Therefore, the embodiment of the invention provides a flywheel energy storage system which has the advantage of good heat dissipation effect.

The flywheel energy storage system comprises a shell, wherein the shell is provided with an inner cavity; a flywheel rotatably mounted within the internal cavity; the sealing assembly is arranged between the shell and the flywheel to realize rotary sealing between the shell and the flywheel, and divides the inner cavity into a cooling cavity and a vacuum cavity, and the vacuum cavity is suitable for reducing the rotation resistance of the flywheel; the stator and the rotor are arranged in the cooling cavity, a cooling medium is suitable for being introduced into the cooling cavity to cool the stator and the rotor, the stator is arranged in the shell, and the rotor is arranged on the flywheel and can rotate under the action of the stator.

The flywheel energy storage system has the advantage of good heat dissipation effect.

In some embodiments, the flywheel includes a shaft portion extending in an axial direction of the housing and a rotor portion partially located in the cooling cavity, the rotor portion is disposed on an outer circumferential side of the shaft portion to increase a rotational inertia of the flywheel, and the rotor portion is disposed in the vacuum cavity.

In some embodiments, the housing is provided with an air inlet hole and an air outlet hole, the air inlet hole is communicated with the cooling cavity, and the air outlet hole is communicated with the cooling cavity so as to be suitable for air to enter and exit the cooling cavity.

In some embodiments, the air inlet is located on one side of the stator and the air outlet is located on the other side of the stator for the cooling medium to flow between the stator and the rotor.

In some embodiments, the air inlet hole is provided in plurality, and the plurality of air inlet holes are arranged at intervals along the circumference of the housing.

In some embodiments, the housing is provided with a cooling passage extending in a circumferential direction of the housing and provided on an outer circumferential side of the stator so as to be adapted to flow a cooling liquid through the housing.

In some embodiments, the casing is provided with a guide groove which is provided on an outer peripheral side of the casing and extends in a circumferential direction of the casing, and the casing includes a seal ring which sealingly covers a notch of the guide groove to form the cooling passage.

In some embodiments, a plurality of protrusions are arranged in the guiding groove, the protrusions are arranged between the sealing ring and the groove bottom of the guiding groove, the protrusions extend along the circumferential direction of the casing, the protrusions are provided with guiding portions, the guiding portions are suitable for allowing cooling liquid to flow from one side of the protrusions to the other side of the protrusions, the protrusions are arranged at intervals along the axial direction of the casing, the cooling liquid flows from one side of the protrusions to the other side of the protrusions to cool the casing, and the guiding portions of two adjacent protrusions are arranged oppositely.

In some embodiments, the sealing assembly includes an annular portion and a sealing liquid, the annular portion is disposed in the inner cavity, an outer wall of the annular portion is in sealing connection with the housing, the annular portion is sleeved on an outer circumferential side of the flywheel, and the sealing liquid is filled between an inner wall of the annular portion and an outer circumferential wall of the flywheel to be suitable for annularly connecting the annular portion and the sealing assembly.

In some embodiments, the annular portion comprises a magnetic ring, the flywheel is rotatably mounted on the magnetic ring with an annular gap therebetween, and the sealing fluid is a magnetic fluid adapted to be constrained by the magnetic ring within the annular gap.

Drawings

Fig. 1 is a schematic structural diagram of a flywheel energy storage system according to an embodiment of the invention.

Fig. 2 is a partially enlarged view of a portion a in fig. 1.

Fig. 3 is a partially enlarged view of fig. 1 at B.

FIG. 4 is a schematic cross-sectional view of a cooling passage of a flywheel energy storage system in an embodiment of the invention.

Reference numerals are as follows:

a housing 1; a first shell 11; a second shell 12; an air outlet hole 121; an air intake hole 122; a cooling channel 123; a guide groove 1231; a boss 1232; a seal ring 1233; a flow guide portion 1234;

a flywheel 2; a wheel shaft portion 21; a rotor portion 22;

a seal assembly 3; the annular portion 31; a magnetic ring 311; an annular flange 3111; a magnetism isolating ring 312;

a rotor 41; and a stator 42.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

The flywheel 2 energy storage system of the embodiment of the invention is described below with reference to fig. 1, 2 and 3.

The flywheel 2 energy storage system of the embodiment of the invention comprises a shell 1, a flywheel 2, a sealing assembly 3, a stator 42 and a rotor 41.

The housing 1 is provided with an inner cavity. The flywheel 2 is rotatably fitted in the inner cavity.

Specifically, the shell 1 extends along the vertical up-down direction, an inner cavity is arranged in the shell 1 and extends along the vertical up-down direction, the inner cavity is a stepped cylindrical hole, the inner cavity and the shell 1 are coaxially arranged, the axis of the flywheel 2 extends along the vertical up-down direction, the flywheel 2 is rotatably assembled in the inner cavity along the axis of the flywheel 2, and the axis of the flywheel 2 coincides with the axis of the shell 1.

The sealing assembly 3 is arranged between the shell 1 and the flywheel 2 to realize the rotary sealing between the shell 1 and the flywheel 2, the sealing assembly 3 divides the inner cavity into a cooling cavity and a vacuum cavity, and the vacuum cavity is suitable for reducing the rotation resistance of the flywheel 2.

Specifically, the sealing assembly 3 is arranged in the inner cavity, the sealing assembly 3 extends in a closed manner along the circumferential direction of the flywheel 2, the sealing assembly 3 is of an annular structure, the inner edge of the sealing assembly 3 is connected with the outer circumferential surface of the flywheel 2 in a sealing manner, the outer edge of the sealing assembly 3 is connected with the inner wall of the shell 1 in a sealing manner, the inner edge of the sealing assembly 3 and the outer edge of the sealing assembly 3 can rotate relatively to allow the flywheel 2 to rotate relative to the shell 1, and the inner edge of the sealing assembly and the outer edge of the sealing assembly 3 are connected in a sealing manner to isolate one side of the sealing assembly 3 in the axial direction from the other side of the sealing assembly 3 in the axial direction.

The part of the inner cavity, which is positioned at the lower side of the sealing component 3, is a vacuum cavity, the part of the inner cavity, which is positioned at the upper side of the sealing component 3, is a cooling cavity, the vacuum cavity is a vacuum environment or is similar to the vacuum environment, and the air density in the vacuum cavity is low, so that when the flywheel 2 rotates along the axis of the flywheel, the viscous resistance of the air in the vacuum cavity to the part of the flywheel 2, which is positioned in the vacuum cavity, is reduced.

The stator 42 and the rotor 41 are arranged in a cooling cavity, the cooling cavity is suitable for being filled with a cooling medium to cool the stator 42 and the rotor 41, the stator 42 is arranged in the shell 1, and the rotor 41 is arranged in the flywheel 2 and can rotate under the action of the stator 42.

Specifically, the rotor 41 is disposed at a portion of the flywheel 2 located in the cooling cavity, the rotor 41 extends in a closed manner along a circumferential direction of the flywheel 2, the stator 42 is disposed at an outer circumferential side of the rotor 41, and the stator 42 extends in a closed manner along an outer circumferential side of the rotor 41, the stator 42 is in an annular structure, the rotor 41 and the flywheel 2 are in rotating fit with an inner edge of the stator 42, an outer edge of the stator 42 is fixedly connected with the housing 1, the stator 42 generates a changing magnetic field when being energized, and the rotor 41 generates an inductive action in the magnetic field generated by the stator 42, so that the rotor 41 together with the flywheel 2 is driven to rotate relative to the stator 42.

The cooling cavity is provided with a flowing cooling medium, the cooling medium is in contact with the stator 42 and the rotor 41 and flows through the gap between the stator 42 and the rotor 41, when the cooling medium flows through the surfaces of the stator 42 and the rotor 41, heat in the stator 42 or the rotor 41 is transferred into the cooling medium through heat exchange, and the cooling medium carries the heat in the stator 42 and the rotor 41 to the outer side of the cooling cavity when flowing out of the cooling cavity so as to cool the stator 42 and the rotor 41.

The flywheel 2 energy storage system of the embodiment of the invention divides the inner cavity of the shell 1 into a vacuum cavity and a cooling cavity through the sealing assembly 3, one part of the flywheel 2 is positioned in the vacuum cavity to reduce the resistance of the part of the flywheel 2 positioned in the vacuum cavity in the rotation process, the other part of the flywheel 2, the stator 42 and the rotor 41 are positioned in the cooling cavity, the stator 42 and the rotor 41 drive the flywheel 2 to rotate relative to the shell 1 to convert electric energy into kinetic energy of the flywheel 2 or convert kinetic energy generated by the flywheel 2 in the rotation process into electric energy through the stator 42 and the rotor 41, in the process of converting the electric energy into the kinetic energy, a part of the energy is lost in the form of internal energy of the stator 42 or the rotor 41, and the cooling medium in the cooling cavity takes away heat in the stator 42 and the rotor 41 to enable the stator 42 and the rotor 41 to be in a working temperature range, so that the flywheel 2 energy storage system of the embodiment of the invention has the advantage of good heat dissipation effect.

In some embodiments, the flywheel 2 includes a shaft portion 21 and a rotor portion 22, the shaft portion 21 extends along the axial direction of the housing 1, a part of the shaft portion 21 is located in the cooling cavity, the rotor portion 22 is disposed on the outer peripheral side of the shaft portion 21 to increase the rotational inertia of the flywheel 2, and the rotor portion 22 is disposed in the vacuum cavity.

Specifically, the wheel shaft 21 extends vertically, the rotor 22 is of a ring structure, the rotor 22 extends circumferentially and closely along the outer circumference of the wheel shaft 21, and the upper end and the lower end of the wheel shaft 21 are respectively provided with an axial magnetic bearing to reduce friction between the wheel shaft 21 and the housing 1 when rotating.

The rotor portion 22 is located at the lower half portion of the axle portion 21 to have high stability, the rotor portions 22 are uniformly distributed along the circumferential direction of the axle portion 21, the outer diameter of the rotor portion 22 is far larger than the maximum diameter of the axle portion 21, and the rotor portion 22 has large moment of inertia, so that the capacity of the flywheel 2 energy storage system of the embodiment of the invention is improved.

Therefore, the outer diameter of the rotor portion 22 is much larger than the maximum diameter of the axle portion 21, so that the outer surface of the rotor portion 22 has a larger linear velocity when the flywheel 2 rotates, the air density in the vacuum chamber is lower, the viscous resistance is smaller, and the rotor portion 22 is located in the vacuum chamber to reduce the resistance of the rotor portion 22 when the flywheel 2 rotates.

In some embodiments, the housing 1 is provided with an air inlet hole 122 and an air outlet hole 121, the air inlet hole 122 is communicated with the cooling cavity, and the air outlet hole 121 is communicated with the cooling cavity to be suitable for air to enter and exit the cooling cavity.

Specifically, the air inlet hole 122 is a through hole penetrating the cooling chamber and the outer surface of the housing 1 in the radial direction of the housing 1, the air outlet hole 121 is a through hole penetrating the cooling chamber and the outer surface of the housing 1 in the radial direction of the housing 1, and the cooling medium is air.

Therefore, air enters the cooling cavity from the outside of the housing 1 through the air inlet holes 122, and the air flows from the cooling cavity to the outside of the housing 1 through the air outlet holes 121, when the flywheel 2 energy storage system of the embodiment of the invention is in operation, heat generated by the stator 42 and the rotor 41 is exchanged to the air in the cooling cavity through convective heat transfer, and when the air flows to the outside of the housing 1 from the air outlet holes 121, the heat in the air in the cooling cavity is exchanged to the outside of the housing 1 through thermal convective heat transfer, so that heat dissipation of the stator 42 and the rotor 41 is completed.

In some embodiments, the air inlet holes 122 are located at one side of the stator 42 and the air outlet holes 121 are located at the other side of the stator 42, so that the cooling medium flows between the stator 42 and the rotor 41.

Specifically, the air inlet holes 122 are located on the upper side of the stator 42, the air outlet holes 121 are located on the lower side of the stator 42, and when the cooling medium flows into the cooling cavity from the air inlet holes 122 and flows out of the cooling cavity from the air outlet holes 121, the cooling medium flows in the direction a in fig. 2.

Therefore, as shown in fig. 2, the cooling medium flows through the gap between the stator 42 and the rotor 41, and the cooling medium is in sufficient contact with the stator 42 and the rotor 41, so that heat is sufficiently convected between the stator 42 or the rotor 41 and the cooling medium, and the cooling effect on the stator 42 and the rotor 41 is improved.

In addition, because the density of the cold air is greater than that of the hot air, the cold air can sink to the lower side of the hot air, and the air inlet 122 is located at the lower side of the air outlet, so that the air with lower temperature, which sinks at the lower position outside the housing 1, enters the cooling cavity through the air inlet 122, and the heat dissipation effect of the flywheel 2 energy storage system in the embodiment of the invention is improved.

In some embodiments, there are a plurality of air inlet holes 122, and the plurality of air inlet holes 122 are arranged at intervals along the circumference of the housing 1.

Specifically, the plurality of air intake holes 122 are arranged at equal intervals along the circumferential direction of the housing 1, and when the cooling medium is air, the plurality of air intake holes 122 can simultaneously supply air outside the housing 1 into the cooling chamber.

Therefore, on one hand, the flow rate of air is improved when the air cools the stator 42 and the rotor 41, on the other hand, the plurality of air inlet holes 122 are arranged at equal intervals along the circumferential direction of the shell 1, so that when the air flows along the gap between the stator 42 and the rotor 41 to generate airflow, the airflow is uniformly distributed along the circumferential direction of the rotor 41, the heat dissipation effect of the air on the stator 42 and the rotor 41 is uniformly distributed, and the heat dissipation effect of the flywheel 2 energy storage system in the embodiment of the invention is improved.

In some embodiments, the housing 1 is provided with a cooling passage 123, and the cooling passage 123 extends in the circumferential direction of the housing 1 and is provided on the outer circumferential side of the stator 42 so as to be adapted for the cooling liquid to flow through the housing 1.

Specifically, the cooling channel 123 extends between the inner cavity and the outer surface of the casing 1, the cooling channel 123 extends along the circumferential direction of the casing 1 on the outer circumferential side of the stator 42, and a cooling liquid is provided in the cooling channel 123, and the cooling liquid flows in the casing 1 along the cooling channel 123, and carries heat conducted from the stator 42 to the casing 1 out of the casing 1 by heat convection with the casing 1 to dissipate the heat of the casing 1.

Therefore, the cooling liquid in the cooling channel 123 dissipates heat to the housing 1 on the outer peripheral side of the stator 42 in the flowing process, so that the temperature of the housing 1 on the outer peripheral side of the stator 42 is reduced, the temperature difference between the stator 42 and the housing 1 is increased, heat generated in the stator 42 is conveniently transferred to the housing 1 through heat conduction, the heat of the stator 42 is reduced, and the heat dissipation effect of the flywheel 2 energy storage system in the embodiment of the invention is improved.

In some embodiments, there are a plurality of cooling channels 123, and the plurality of cooling channels 123 extends along the circumferential closed circumference of the casing 1. In other embodiments, the cooling channel 123 extends helically along the circumference of the housing 1.

In some embodiments, the casing 1 is provided with a guide groove 1231, the guide groove 1231 is provided on the outer peripheral side of the casing 1 and extends along the circumferential direction of the casing 1, and the casing 1 includes a sealing ring 1233, and the sealing ring 1233 is sealed and covered on the notch of the guide groove 1231 to form the cooling passage 123.

Specifically, the guide groove 1231 is disposed on the outer peripheral side of the casing 1 and is communicated with the outer side surface of the casing 1, the guide groove 1231 is located on the outer peripheral side of the stator 42, the sealing ring 1233 is of an annular structure, the inner edge of the sealing ring 1233 covers the notch of the guide groove 1231, and the inner edge of the sealing ring 1233 is hermetically connected to the casing 1 to seal the guide groove 1231 to form the cooling channel 123, so as to prevent the coolant in the guide groove 1231 from overflowing.

From this, guiding gutter 1231 locates the periphery side of casing 1 and communicates with the lateral surface of casing 1, is convenient for process guiding gutter 1231 at the surface of casing 1 on the one hand, and on the other hand is convenient for overhaul guiding gutter 1231 after taking off sealing ring 1233.

In some embodiments, a plurality of protrusions 1232 are disposed in the guiding groove 1231, the protrusions 1232 are disposed between the sealing ring 1233 and the bottom of the guiding groove 1231, the protrusions 1232 extend along the circumferential direction of the casing 1, the protrusions 1232 are provided with guiding portions 1234, the guiding portions 1234 are adapted to allow the coolant to flow from one side of the protrusions 1232 to the other side of the protrusions 1232, the plurality of protrusions 1232 are arranged at intervals along the axial direction of the casing 1, the coolant flows from one side of the plurality of protrusions 1232 to the other side of the plurality of protrusions 1232 to cool the casing 1, and the guiding portions 1234 of two adjacent protrusions 1232 are arranged oppositely.

Specifically, the protrusions 1232 are circular-ring-shaped flanges, the outer edges of the protrusions 1232 are provided with notches to form the flow guiding portions 1234, as shown in fig. 4, when the coolant flows from one side of the protrusions 1232 to the other side of the protrusions 1232, the coolant sequentially passes through the protrusions 1232, when the coolant passes through a certain protrusion 1232, the coolant flows from one side of the protrusion 1232 to the other side of the protrusion 1232 along the flow guiding portion in the protrusion 1232, and the projections of the flow guiding portions 1234 of the protrusions 1232 in the axial direction of the housing 1 are symmetrically arranged along the radial direction of the housing 1.

Therefore, when the coolant flows in the flow guide groove 1231, on one hand, the contact area between the coolant and the groove wall of the flow guide groove 1231 is increased by the protrusions 1232, that is, the convection area between the coolant and the housing 1 is increased, so that the heat dissipation effect of the energy storage system of the flywheel 2 according to the embodiment of the present invention is improved, on the other hand, the protrusions 1232 have a disturbance effect on the coolant in the flow guide groove 1231, when the coolant flows in the flow guide groove 1231, the turbulence of the coolant is increased by the protrusions 1232, so that the convection heat transfer effect between the coolant and the housing 1 is improved, and the heat dissipation effect of the energy storage system of the flywheel 2 according to the embodiment of the present invention is improved.

In some embodiments, the sealing assembly 3 includes an annular portion 31 and a sealing liquid, the annular portion 31 is disposed in the inner cavity, an outer wall of the annular portion 31 is connected to the housing 1 in a sealing manner, the annular portion 31 is sleeved on an outer peripheral side of the flywheel 2, and the sealing liquid is filled between an inner wall of the annular portion 31 and an outer peripheral wall of the flywheel 2 to be suitable for connecting the annular portion 31 and the sealing assembly 3 in an annular manner.

Specifically, the sealing assembly 3 includes an annular portion 31 disposed on an outer peripheral side of the flywheel 2, an outer edge of the annular portion 31 is fixedly and sealingly connected to an inner wall of the inner cavity, a set gap is provided between an inner edge of the annular portion 31 and an outer wall of the flywheel 2, the set gap is filled with a sealing liquid, and the annular portion 31 confines the sealing liquid in the set gap.

Therefore, the sealing liquid is filled between the annular part 31 and the outer surface of the flywheel 2, on one hand, the annular part 31 is in sealing connection with the flywheel 2, on the other hand, the viscous resistance of the sealing liquid is small, the friction effect between the sealing assembly 3 and the flywheel 2 is small, the gas pressure difference between the vacuum cavity and the cooling cavity is large, the sealing liquid is restrained in the set gap through the annular part 31, the sealing effect of the sealing assembly 3 is convenient to improve, the vacuum cavity is kept in high vacuum degree, and the resistance of the flywheel 2 in rotation is reduced.

In some embodiments, the annular portion 31 includes a magnetic ring 311, the flywheel 2 is rotatably mounted on the magnetic ring 311, and an annular gap is formed between the flywheel 2 and the magnetic ring 311, and the sealing fluid is a magnetic fluid suitable for being constrained in the annular gap by the magnetic ring 311.

Specifically, the magnetic ring 311 has magnetism, the sealing fluid is magnetic fluid, and the magnetic induction line direction inside the magnetic ring 311 extends in the vertical up-down direction, and under the action of the magnetic field generated by the magnetic ring 311, the sealing fluid is confined in the annular gap.

Therefore, on one hand, the magnetic fluid has smaller viscous resistance, which is convenient for reducing the resistance of the sealing component 3 to the rotation of the flywheel 2, and on the other hand, the magnetic fluid can be filled in the magnetic ring 311

The annular portion 31 includes a magnetism isolating ring 312, and the magnetism isolating ring 312 is disposed between the magnetic ring 311 and the housing 1 and sleeved on the outer periphery of the magnetic ring 311 for increasing the magnetic field intensity in the annular gap.

In some embodiments, the inner wall of the magnetic ring 311 is provided with a plurality of annular flanges 3111, the plurality of annular flanges 3111 being arranged at intervals in the axial direction of the flywheel 2, the annular flanges 3111 projecting toward the flywheel 2 to be adapted to focus the magnetic field between the annular flanges 3111 and the flywheel 2.

Therefore, the gap between the inner edges of the annular flanges 3111 and the outer surface of the flywheel 2 is smaller than the set annular gap, so that the sealing liquid is confined between the annular flanges 3111 and the flywheel 2 to improve the sealing effect of the seal assembly 3, and the annular flanges 3111 form multi-stage sealing to improve the sealing effect of the seal assembly 3.

In some embodiments, the casing 1 includes a first casing 11 and a second casing 12, the first casing 11 is disposed at a lower side of the second casing 12, the second casing 12 and the first casing 11 are sealably assembled to form the casing 1, the first casing 11 is disposed at an outer peripheral side of the rotor portion 22, an upper end of the first casing 11 has an opening for the shaft portion to pass through, a lower end of the second casing 12 has an opening for the shaft portion to pass through, and a lower end of the second casing 12 is in sealing engagement with an upper end of the first casing 11.

Thus, the housing 1 has a vertically split structure, and after the flywheel 2 is mounted to the first housing 11, the housing 1 can be mounted to the outer peripheral side of the flywheel 2 by fitting the second housing 12 over the flywheel 2 to the upper end of the first housing 11, thereby facilitating assembly of the flywheel 2 and the housing 1. The rotor part 22, the stator 42, the air inlet holes 122, the air outlet holes 121 and the sealing assembly 3 are arranged in the second shell 12, so that on one hand, the second shell 12 with a smaller size can be conveniently machined, and on the other hand, the second shell 12 can be conveniently detached from the flywheel 2 for maintenance.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, but are not intended to indicate or imply that the device or element so referred to must have a particular orientation, be constructed in a particular orientation, and be operated in a particular manner, and are not to be construed as limiting the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to implicitly indicate the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; may be mechanically coupled, may be electrically coupled or may be in communication with each other; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood according to specific situations by those of ordinary skill in the art.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the present disclosure, the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples" and the like mean that a specific feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although the above embodiments have been shown and described, it should be understood that they are exemplary and should not be construed as limiting the present invention, and that many changes, modifications, substitutions and alterations to the above embodiments may be made by those of ordinary skill in the art without departing from the scope of the present invention.

Claims

1. A flywheel energy storage system, comprising:

the shell is provided with an inner cavity;

a flywheel rotatably mounted within the internal cavity;

the sealing assembly is arranged between the shell and the flywheel to realize rotary sealing between the shell and the flywheel, and divides the inner cavity into a cooling cavity and a vacuum cavity, and the vacuum cavity is suitable for reducing the rotation resistance of the flywheel;

the stator and the rotor are arranged in the cooling cavity, a cooling medium is suitable for being introduced into the cooling cavity to cool the stator and the rotor, the stator is arranged in the shell, and the rotor is arranged on the flywheel and can rotate under the action of the stator.

2. The flywheel energy storage system of claim 1, wherein the flywheel comprises a hub portion extending in an axial direction of the housing and a rotor portion, wherein a portion of the hub portion is located in the cooling cavity, wherein the rotor portion is disposed on an outer circumferential side of the hub portion to increase a rotational inertia of the flywheel, and wherein the rotor portion is disposed in the vacuum cavity.

3. The flywheel energy storage system of claim 2 wherein the housing defines an air inlet aperture and an air outlet aperture, the air inlet aperture communicating with the cooling cavity and the air outlet aperture communicating with the cooling cavity for allowing air to enter and exit the cooling cavity.

4. The flywheel energy storage system of claim 3, wherein the air inlet is located on one side of the stator and the air outlet is located on the other side of the stator for the cooling medium to flow between the stator and the rotor.

5. The flywheel energy storage system of claim 4, wherein the air inlet holes are a plurality of air inlet holes spaced circumferentially along the housing.

6. The flywheel energy storage system according to claim 5, wherein the housing is provided with a cooling passage extending in a circumferential direction of the housing and provided on an outer circumferential side of the stator so as to be adapted to allow a cooling fluid to flow through the housing.

7. The flywheel energy storage system according to claim 6, wherein the housing is provided with a guide groove which is provided on an outer peripheral side of the housing and extends in a circumferential direction of the housing, and the housing includes a seal ring which sealingly covers a notch of the guide groove to form the cooling passage.

8. The flywheel energy storage system of claim 7, wherein a plurality of protrusions are disposed in the guiding groove, the protrusions are disposed between the sealing ring and a bottom of the guiding groove, and extend along a circumferential direction of the casing, the protrusions are provided with guiding portions, the guiding portions are suitable for allowing a coolant to flow from one side of the protrusions to the other side of the protrusions, the protrusions are arranged along an axial direction of the casing at intervals, the coolant flows from one side of the protrusions to the other side of the protrusions to cool the casing, and the guiding portions of two adjacent protrusions are arranged oppositely.

9. The flywheel energy storage system according to any one of claims 1 to 7, wherein the seal assembly includes an annular portion and a sealing liquid, the annular portion is provided in the inner cavity and an outer wall of the annular portion is sealingly connected to the housing, the annular portion is fitted around an outer peripheral side of the flywheel, and the sealing liquid is filled between an inner wall of the annular portion and an outer peripheral wall of the flywheel to be adapted to annularly connect the annular portion and the seal assembly.

10. The flywheel energy storage system of claim 9, wherein the annular portion comprises a magnetic ring, the flywheel is rotatably mounted to the magnetic ring with an annular gap therebetween, and the sealing fluid is a magnetic fluid adapted to be constrained within the annular gap by the magnetic ring.