Energy storage flywheel with annular rotor
By adopting annular rotor and vacuum cavity design in the energy storage flywheel, the problems of low moment of inertia and insufficient strength of the rotor core are solved, and the moment of inertia and the increase of space energy density are achieved.
Patent Information
- Application Number
- CN202420897011.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-28
- Publication Date
- 2025-03-04
- Estimated Expiration
- 2034-04-28
AI Technical Summary
The rotors of existing energy storage flywheels are mostly cylindrical, resulting in a small moment of inertia and insufficient strength of the rotor core, which affects the increase of energy storage energy.
Using an annular rotor, by setting a vacuum cavity and a support part inside the housing, and embeding the stator assembly and axial magnetic bearing assembly on the top and bottom surfaces of the housing, the annular rotor is driven to rotate and increase the moment of inertia and the space energy density.
Under the same weight conditions, the moment of inertia of the annular rotor increases by about 25%, while increasing the space energy density and enhancing the strength of the rotor core.
Smart Images
Figure CN222563577U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of flywheel structures, and in particular to an energy storage flywheel with an annular rotor. Background Art
[0002] Energy storage flywheel refers to a new energy storage method that uses an electric motor to drive a flywheel to rotate at high speed, converting electrical energy into mechanical energy and storing it, and then converting mechanical energy into electrical energy when needed. It is proportional to the moment of inertia j and the angular velocity ω, and the moment of inertia j is directly related to the specific shape of the rotor, which also determines the size of the corresponding moment of inertia.
[0003] At present, most of the rotors of conventional energy storage flywheels on the market are cylindrical. Under the same mass conditions, the moment of inertia of the cylindrical rotor is about 25% smaller than that of the annular rotor. In addition, compared with the annular rotor, the weak rotor core strength of the cylindrical rotor has always been a common problem that is difficult to overcome for large-diameter flywheel rotors, which will also affect its moment of inertia to a certain extent. Therefore, there is a need for an energy storage flywheel using an annular rotor to increase the moment of inertia and thereby increase the energy storage capacity of the flywheel. Utility Model Content
[0004] In order to solve the existing problems in the background technology, the present application proposes an energy storage flywheel with an annular rotor.
[0005] On one hand, the present application provides an energy storage flywheel with an annular rotor, comprising: a housing, a stator assembly, an annular rotor and an axial magnetic bearing assembly;
[0006] A vacuum cavity is arranged inside the shell, and a support portion is arranged in the middle of the bottom of the shell along the vertical direction of the vacuum cavity;
[0007] The stator assembly includes a first stator, and the first stator is sleeved on the outer side of the support portion;
[0008] The annular rotor is sleeved on the outside of the first stator and does not contact the first stator;
[0009] The axial magnetic bearing assembly is relatively embedded in the top surface and the bottom surface of the shell.
[0010] The above-mentioned energy storage flywheel with an annular rotor, the housing comprises a shell, an upper cover and a sealing plate;
[0011] The upper cover is arranged on the top of the shell, and the top end of the support portion extends from the inside of the shell toward the upper cover and is flush with the top surface of the upper cover. The sealing plate is arranged at the center position of the top surface of the upper cover, and the bottom surface of the sealing plate is in contact with the top surface of the support portion.
[0012] In the above-mentioned energy storage flywheel with an annular rotor, the upper cover is provided with a through hole, and the through hole is suitable for connecting an external vacuum pump to evacuate the interior of the shell.
[0013] In the above-mentioned energy storage flywheel with an annular rotor, the axial magnetic bearing assembly includes an upper axial magnetic bearing and a lower axial magnetic bearing; the number of the upper axial magnetic bearing and the number of the lower axial magnetic bearing are the same, both are multiple;
[0014] The distances between the two sides of the upper axial magnetic bearing and the two sides of the annular rotor in the horizontal direction are the same.
[0015] In the above-mentioned energy storage flywheel with an annular rotor, the distance between the upper axial magnetic bearing and the top surface of the annular rotor is the same as the distance between the lower axial magnetic bearing and the bottom surface of the annular rotor.
[0016] The above-mentioned energy storage flywheel with an annular rotor further includes a friction assembly, wherein the friction assembly includes a first friction member;
[0017] The first friction member is located on the bottom surface of the housing, and the top surface of the first friction member is in contact with the bottom surface of the annular rotor.
[0018] In the above-mentioned energy storage flywheel with an annular rotor, the friction assembly also includes second friction members, and the second friction members are located on the side of the shell, and the number of the second friction members is at least two.
[0019] In the above-mentioned energy storage flywheel with an annular rotor, the material of the friction component is soft metal.
[0020] Beneficial effects of this application:
[0021] The energy storage flywheel of the present application is provided with an annular rotor. Under the condition of the same weight, the moment of inertia of the annular rotor is increased by about 25% compared with the moment of inertia of the cylindrical rotor, and the spatial energy density is also increased. Specifically, the energy storage flywheel with an annular rotor of the present application includes: a housing, a stator assembly, an annular rotor and an axial magnetic bearing assembly. A vacuum chamber is provided inside the housing, and a support portion is provided in the middle of the bottom of the housing along the vertical direction of the vacuum chamber. The stator assembly includes a first stator, and the first stator is sleeved on the outside of the support portion. The annular rotor is sleeved on the outside of the first stator and is not in contact with the first stator. The axial magnetic bearing assembly is relatively embedded in the top and bottom surfaces of the housing. That is, a vacuum chamber is provided inside the housing of the present application, which can effectively reduce the air resistance inside the housing, and the use of an annular rotor increases the moment of inertia and spatial energy density of the rotor.
[0022] Other features and aspects of the present application will become apparent from the following detailed description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments, features, and aspects of the present application and, together with the description, serve to explain the principles of the present application.
[0024] Figure 1 A central cross-sectional view of an energy storage flywheel with an annular rotor according to an embodiment of the present application is shown;
[0025] Figure 2 A top view of an energy storage flywheel with an annular rotor according to an embodiment of the present application is shown. DETAILED DESCRIPTION
[0026] Various exemplary embodiments, features and aspects of the present application will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.
[0027] Among them, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application or simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.
[0028] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.
[0029] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.
[0030] In addition, in order to better illustrate the present application, numerous specific details are given in the following specific embodiments. It should be understood by those skilled in the art that the present application can also be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present application.
[0031] like Figure 1 As shown, the energy storage flywheel with an annular rotor includes: a housing 100, a stator assembly, an annular rotor 300 and an axial magnetic bearing assembly. The housing 100 is provided with a vacuum chamber, and a support portion 140 is provided in the middle of the bottom of the housing 100 along the vertical direction of the vacuum chamber. The stator assembly includes a first stator 200, and the first stator 200 is sleeved on the outside of the support portion 140. The annular rotor 300 is sleeved on the outside of the first stator 200 and is not in contact with the first stator 200. The axial magnetic bearing assembly is relatively embedded in the top and bottom surfaces of the housing 100.
[0032] In the present embodiment, a vacuum chamber is provided inside the housing 100, which can effectively reduce the air resistance inside the housing 100, so that the stator assembly and the axial magnetic bearing assembly provided in the housing 100 can cooperate with each other to drive the annular rotor 300 to rotate. In addition, the annular rotor 300 is in a circular ring shape, and the rotor core strength is higher than that of the cylindrical rotor, thereby effectively increasing the rotor's moment of inertia and spatial energy density.
[0033] In one possible implementation, the shell 100 includes a shell 110, an upper cover 120 and a sealing plate 130; the upper cover 120 is arranged on the top of the shell 110, and the top end of the support portion 140 extends from the inside of the shell 100 to the upper cover 120, and is arranged flush with the top surface of the upper cover 120, the sealing plate 130 is arranged at the center position of the top surface of the upper cover 120, and the bottom surface of the sealing plate 130 is in contact with the top surface of the support portion 140.
[0034] See also Figure 1, the top of the support part 140 extends out of the outer side of the shell 110 and is flush with the top of the upper cover 120, wherein the cross section of the upper cover 120 in the horizontal direction is a circular structure, and a circular through hole is opened in the center of the upper cover 120, and the top of the support part extends from the circular through hole on the upper cover 120 to the direction close to the top of the upper cover 120, and the top surface is flush with the top surface of the upper cover 120. Its circular through hole is used to connect the extended part of the support column 140. The bottom surface of the cross section of the upper cover 120 is connected to the shell 110 by bolts, and the surrounding of the circular through hole is connected to the extended part of the support part 140 by bolts. In addition, the present application is also provided with a sealing plate 130, specifically, the sealing plate 130 is correspondingly arranged at the position of the circular through hole in the center of the top surface of the upper cover 120, and the size of the sealing plate 130 is larger than the aperture of the circular through hole, and is bolted to the upper cover 120. As a result, a vacuum chamber is formed inside the housing 100 for placing the annular rotor 300.
[0035] It should be noted that the stator assembly, the annular rotor 300 and the axial magnetic bearing assembly are all inside the housing 100. Figure 2 As shown, the cross section of the annular rotor 300 is a circular ring structure, that is, the interior of the annular rotor 300 is a hollow cylindrical structure, which is used to cover the support part 140 and the stator assembly; through the stator assembly, when power is turned on, the annular rotor 300 can be driven to rotate synchronously to realize the conversion of electrical energy into mechanical energy.
[0036] In a possible implementation, a through hole 400 is provided on the upper cover 120 , and the through hole 400 is suitable for connecting an external vacuum pump to evacuate the interior of the housing 100 .
[0037] In this embodiment, the through hole 400 is used to connect an external vacuum pump to extract gas from the cavity formed by the support part 140, the shell 110, the upper cover 120 and the sealing plate 130 to achieve a certain vacuum degree, which is used to reduce the air friction resistance when the annular rotor 300 rotates, reduce heat, and thus reduce losses.
[0038] In one possible implementation, the axial magnetic bearing assembly includes an upper axial magnetic bearing 510 and a lower axial magnetic bearing 520; the number of the upper axial magnetic bearing 510 and the number of the lower axial magnetic bearing 520 are the same, both are multiple; the two sides of the upper axial magnetic bearing 510 are the same distance from the two sides of the annular rotor 300 in the horizontal direction.
[0039] In this embodiment, the axial magnetic bearing assembly includes an upper axial magnetic bearing 510 and a lower axial magnetic bearing 520, and the upper axial magnetic bearing 510 is embedded in the lower part of the upper cover 120 of the housing 100. The lower axial magnetic bearing 520 is embedded in the upper part of the bottom surface of the housing 110, and the upper axial magnetic bearing 510 and the lower axial magnetic bearing 520 are arranged in a corresponding and matching manner, and both are provided with coil windings inside, and the operation of the annular rotor 300 is carried by the magnetic force generated by the coil windings, so the number of the two needs to be consistent, and the number of the two is multiple in the energy storage flywheel, that is, three or more.
[0040] The left and right sides of the upper axial magnetic bearing 510 are at the same distance from the two sides of the annular rotor 300. Similarly, the left and right sides of the lower axial magnetic bearing 520 are also at the same distance from the two sides.
[0041] In a possible implementation, the distances between the upper axial magnetic bearing 510 and the lower axial magnetic bearing 520 and the top surface and the bottom surface of the annular rotor 300 are the same.
[0042] That is, the distance between the bottom surface of the upper axial magnetic bearing 510 and the top surface of the annular rotor 300 is the same as the distance between the top surface of the lower axial magnetic bearing 520 and the bottom surface of the annular rotor 300. Thus, the position of the axial magnetic bearing at the other end can be obtained from the distance from one axial magnetic bearing to both sides of the annular rotor 300 in the horizontal direction and the distance from the surface of the annular rotor 300 in the vertical direction.
[0043] In a possible implementation, a friction assembly 600 is further included. The friction assembly includes a first friction member 610 . The first friction member 610 is located on the bottom surface of the housing 100 , and the top surface of the first friction member 610 is in contact with the bottom surface of the annular rotor 300 .
[0044] It should be particularly noted that when the energy storage flywheel with an annular rotor of the present application does not start working, the bottom surface of the annular rotor 300 fits against the top surface of the first friction member 610 , reducing the weight pressure of the annular rotor 300 in the housing 100 and slowing down the loss of the housing 100 .
[0045] In one scenario, the first friction member 610 of the present application is preferably a rectangular block, and there are multiple of them. At this time, at least two groups are arranged between the shell 110 and the support column 140, and each group includes two rectangular blocks, that is, two rectangular friction blocks are arranged at intervals between one side of the shell 110 and the support part, and the other side is arranged in the same way, and the repeated parts are not repeated here.
[0046] In another scenario, the first friction member 610 of the present application is preferably an annular friction belt, and the number is at least two, which are circumferentially arranged on the outside of the support part in sequence, and the circumference length of the friction belt close to the support column 140 is smaller than the circumference length of the friction belt away from the support part.
[0047] In a possible implementation, the friction assembly 600 further includes a second friction member 510 . The second friction members 620 are located on the side surface of the housing 100 , and the number of the second friction members is at least two.
[0048] It should be noted that in one scenario, the second friction member 620 of the present application is preferably a rectangular block, and there are multiple of them, at least two groups are provided, each group includes two rectangular blocks, and in this case, a group of rectangular blocks are arranged around the side of the housing 100.
[0049] In another scenario, the second friction member 620 of the present application is preferably in the form of a friction belt structure, with at least two of them. In this case, the friction belts are all circumferentially arranged along the inner circumference of the side wall of the housing 100 .
[0050] After the friction assembly 600 is set, when the energy storage flywheel with an annular rotor of the present application starts working, when a fault occurs, the annular rotor 300 can come into contact with the friction assembly 600, quickly reducing the rotation speed of the annular rotor 300 and the impact on the outer casing 100, etc., to achieve protection and avoid damage.
[0051] In a possible implementation, the friction component 600 is made of soft metal.
[0052] Soft metal materials have the advantages of greater damping and impact consumption. The material of the friction component 600 is soft metal, which can achieve speed reduction and impact consumption of the annular rotor 300.
[0053] The embodiments of the present application have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.
Claims
1. An energy storage flywheel with an annular rotor, characterized in that: include: housing, stator assembly, annular rotor and axial magnetic bearing assembly; A vacuum cavity is arranged inside the shell, and a support portion is arranged in the middle of the bottom of the shell along the vertical direction of the vacuum cavity; The stator assembly includes a first stator, and the first stator is sleeved on the outer side of the support portion; The annular rotor is sleeved on the outside of the first stator and does not contact the first stator; The axial magnetic bearing assembly is relatively embedded in the top surface and the bottom surface of the shell.
2. The energy storage flywheel with an annular rotor according to claim 1, characterized in that: The housing comprises a shell, an upper cover and a sealing plate; The upper cover is arranged on the top of the shell, and the top end of the support portion extends from the inside of the shell toward the upper cover and is flush with the top surface of the upper cover. The sealing plate is arranged at the center position of the top surface of the upper cover, and the bottom surface of the sealing plate is in contact with the top surface of the support portion.
3. The energy storage flywheel with an annular rotor according to claim 2, characterized in that: The upper cover is provided with a through hole, and the through hole is suitable for connecting an external vacuum pump to evacuate the interior of the shell.
4. The energy storage flywheel with an annular rotor according to claim 1, characterized in that: The axial magnetic bearing assembly comprises an upper axial magnetic bearing and a lower axial magnetic bearing; the number of the upper axial magnetic bearing and the number of the lower axial magnetic bearing are the same, both are multiple; The distances between the two sides of the upper axial magnetic bearing and the two sides of the annular rotor in the horizontal direction are the same.
5. The energy storage flywheel with an annular rotor according to claim 4, characterized in that: The distance between the upper axial magnetic bearing and the top surface of the annular rotor is the same as the distance between the lower axial magnetic bearing and the bottom surface of the annular rotor.
6. The energy storage flywheel with an annular rotor according to claim 1, characterized in that: Also included is a friction assembly, the friction assembly including a first friction member; The first friction member is located on the bottom surface of the housing, and the top surface of the first friction member is in contact with the bottom surface of the annular rotor.
7. The energy storage flywheel with an annular rotor according to claim 6, characterized in that: The friction assembly further includes a second friction member, which is located on a side surface of the housing and has at least two second friction members.
8. The energy storage flywheel with an annular rotor according to claim 6 or 7, characterized in that: The material of the friction component is soft metal.