High-power flywheel energy storage device

Abstract

The invention discloses a high-power flywheel energy storage device which comprises a rotor, a stator set, a machine shell and a permanent magnet set. The rotor comprises a first flywheel rotor, a second flywheel rotor and a shaft core, the first flywheel rotor and the second flywheel rotor are coaxially arranged on the shaft core, the first flywheel rotor, the second flywheel rotor and the shaft core are integrally formed, the stator set is arranged between the rotor and the machine shell, and the permanent magnet set is arranged between the rotor and the stator set. According to the high-power flywheel energy storage device, the upper and lower flywheel structures are matched with the stator group on the basis of the compressive and non-tensile mechanical characteristics of permanent magnets, so that the permanent magnet group positioned between the rotor and the stator group can rotate at a high speed along with the rotor when the flywheel rotor rotates at a high speed, and therefore, a sheath winding process is avoided, and the service life of the flywheel rotor is prolonged. Therefore, the flywheel rotor can rotate to a high rotating speed, and the energy storage capacity of the flywheel energy storage system is more ideal.

Description

Technical Field

[0001] This invention belongs to the field of motor technology, and specifically discloses a high-power flywheel energy storage device. Background Technology

[0002] Flywheel energy storage systems, as an advanced physical energy storage technology, store electrical energy in the form of kinetic energy through a high-speed rotating flywheel. They offer significant advantages such as rapid charging and discharging, long cycle life, and environmental friendliness. Therefore, flywheel energy storage technology shows broad application prospects in areas such as power system frequency regulation, uninterruptible power supplies, energy recovery in rail transit, and grid connection of new energy sources.

[0003] Flywheel energy storage systems exist in three different states: charging, standby, and discharging. These systems often remain in an idle standby state for extended periods. To reduce standby losses and improve energy conversion efficiency, a coreless stator structure is the most common choice for flywheel energy storage systems. However, using a coreless stator structure typically leads to a larger air gap length, reducing the system's power output.

[0004] In summary, developing a novel flywheel energy storage system that can reduce standby losses and improve energy conversion efficiency has become a pressing technical challenge in the field of flywheel energy storage. Summary of the Invention

[0005] (a) Technical problems to be solved Based on this, the present invention provides a high-power flywheel energy storage device to solve the technical problems of significant standby loss and difficulty in integrating higher power within a limited volume in the existing flywheel energy storage system.

[0006] (II) Technical Solution To solve the above-mentioned technical problems, the present invention proposes a high-power flywheel energy storage device, which includes: a rotor, a stator assembly, a housing, and a permanent magnet assembly; The rotor includes a first flywheel rotor and a second flywheel rotor and a shaft core. The first flywheel rotor and the second flywheel rotor are coaxially arranged on the shaft core and the first flywheel rotor, the second flywheel rotor and the shaft core are integrally formed. The stator assembly is arranged between the rotor and the housing, and the permanent magnet assembly is arranged between the rotor and the stator assembly.

[0007] Preferably, the permanent magnet assembly includes a first permanent magnet ring, a second permanent magnet ring, and a pair of intermediate permanent magnet rings; Both the first and second flywheel rotors have paired mounting slots. The stator assembly is located in the mounting slots and connected to the housing. The first and second permanent magnet rings are both disposed in the mounting slots and are located between the stator assembly and the first and second flywheel rotors. An intermediate cavity is formed between the first and second flywheel rotors. The paired intermediate permanent magnet rings are respectively disposed on the first and second flywheel rotors.

[0008] Preferably, the housing includes an upper end cover, a lower end cover, and a shell; Both the upper and lower end caps are detachably mounted on the housing. A stator slot is provided on the central axis of the housing to install and engage the stator located in the intermediate cavity.

[0009] Preferably, the stator group includes a first stator, a second stator, and an intermediate stator; The first stator is fixedly disposed on the upper end cover and located in the mounting groove of the first flywheel rotor. The first permanent magnet ring is located between the first stator and the first flywheel rotor. The second stator is fixedly disposed on the lower end cover and located in the mounting groove of the second flywheel rotor. The second permanent magnet ring is located between the second stator and the second flywheel rotor. The intermediate stator is fixedly disposed in the stator groove and located in the intermediate cavity. Pairs of intermediate permanent magnet rings are located on both sides of the intermediate stator and are located between the intermediate stator and the first flywheel rotor, and between the intermediate stator and the second flywheel rotor, respectively.

[0010] Preferably, the intermediate cavity further includes a pair of abutment rings, which are respectively disposed on opposite sides of the first flywheel rotor and the second flywheel rotor. The abutment rings facing the shaft core abut against the intermediate permanent magnet ring to increase the rated speed of the flywheel rotor.

[0011] Preferably, the housing further includes an upper mechanical bearing and a lower mechanical bearing; the upper cover and the lower cover are respectively connected to the shaft core through the upper mechanical bearing and the lower mechanical bearing.

[0012] Preferably, the first permanent magnet ring, the second permanent magnet ring, and the intermediate permanent magnet ring each include multiple permanent magnets, and the multiple permanent magnets are arranged one by one to form a permanent magnet ring.

[0013] Preferably, the permanent magnets of adjacent permanent magnets in the first permanent magnet ring, the second permanent magnet ring, and the intermediate permanent magnet ring have opposite magnetic poles in the circumferential direction, and the permanent magnets of the paired intermediate permanent magnet rings that are located in the same vertical plane in the vertical direction have the same magnetic poles.

[0014] Preferably, the first stator, the second stator, and the intermediate stator each include a non-magnetic and non-conductive stator support and an armature winding, wherein the armature winding is fixedly mounted on the stator support.

[0015] (III) Beneficial Effects Compared with existing technologies, the high-power flywheel energy storage device of the present invention has the following advantages: This high-power flywheel energy storage device features a rotor with an upper and lower double flywheel structure. Based on the mechanical property of permanent magnets being "compressive but not tensile," the cooperation between the upper and lower flywheel structures and the stator assembly allows the permanent magnet assembly located between the rotor and stator assembly to experience inward compressive stress from the flywheel rotor as it rotates at high speed. This effectively increases the flywheel rotor's speed and energy storage capacity. The permanent magnet assembly can rotate with the rotor at high speed, thus avoiding the need for sheath winding and allowing the flywheel rotor to reach higher speeds, further enhancing the energy storage capacity of the flywheel energy storage system.

[0016] Furthermore, the high-power flywheel energy storage device places the stator assembly between the rotor and the housing, and the permanent magnet assembly between the rotor and the stator assembly, which further makes the structure of the high-power flywheel energy storage device more compact, improves the fault tolerance of the flywheel energy storage system and increases the power of the flywheel energy storage system, thereby integrating higher power within a limited volume.

[0017] The stator support uses non-magnetic and non-conductive materials, which further eliminates stator core losses, improves the energy conversion efficiency of the flywheel energy storage system, and makes the motor run more stably. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the overall structure of the high-power flywheel energy storage device of the present invention; Figure 2 This is a schematic diagram of the rotor structure of the high-power flywheel energy storage device of the present invention; Figure 3 This is a schematic diagram of the rotor cross-sectional structure of the high-power flywheel energy storage device of the present invention; Figure 4 This is a schematic diagram of the structure of the high-power flywheel energy storage device rotor with attached permanent magnets according to the present invention; Figure 5This is a schematic cross-sectional view of the high-power flywheel energy storage device of the present invention.

[0020] Explanation of reference numerals in the attached figures: 1. Rotor; 2. First permanent magnet ring; 3. First intermediate permanent magnet ring; 4. Intermediate stator; 5. Second intermediate permanent magnet ring; 6. Second permanent magnet ring; 7. Upper mechanical bearing; 8. Upper cover; 9. First stator; 10. First abutment ring; 11. Second abutment ring; 12. Second stator; 13. Lower cover; 14. Lower mechanical bearing; 15. Housing. Detailed Implementation

[0021] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0022] The following is in conjunction with the appendix Figure 1-5 The high-power flywheel energy storage device of the present invention will be further described.

[0023] Please refer to this carefully. Figure 1 and Figure 5 This invention discloses a high-power flywheel energy storage device, which includes: a rotor 1, a stator assembly, a housing, and a permanent magnet assembly; the rotor 1 includes a first flywheel rotor 1, a second flywheel rotor 1, and a shaft core, the first flywheel rotor 1 and the second flywheel rotor 1 are coaxially arranged on the shaft core and the first flywheel rotor 1, the second flywheel rotor 1 and the shaft core are integrally formed, the stator assembly is arranged between the rotor 1 and the housing, and the permanent magnet assembly is arranged between the rotor 1 and the stator assembly.

[0024] In this embodiment, the high-power flywheel energy storage device uses a rotor 1 with a double flywheel structure. Through the cooperation of the two flywheel structures and the stator assembly, the permanent magnet assembly located between the rotor 1 and the stator assembly experiences inward compressive stress from the rotor 1 as the rotor 1 rotates at high speed. This effectively increases the rotational speed of the rotor 1 and its energy storage capacity. Furthermore, this structural design avoids the carbon fiber winding process, mitigating the technical challenge of carbon fiber heating in traditional flywheel energy storage, resulting in more stable motor operation. Furthermore, placing the stator assembly between the rotor 1 and the housing, and the permanent magnet assembly between the rotor 1 and the stator assembly, further enhances the compactness of the high-power flywheel energy storage device, improving the fault tolerance and power of the flywheel energy storage system, thus integrating higher power within a limited volume.

[0025] like Figures 2-5 As shown, the permanent magnet assembly includes a first permanent magnet ring 2, a second permanent magnet ring 6, and a pair of intermediate permanent magnet rings; both the first flywheel rotor 1 and the second flywheel rotor 1 have a pair of mounting slots, the stator assembly is located in the mounting slots and connected to the housing, the first permanent magnet ring 2 and the second permanent magnet ring 6 are both set in the mounting slots and are located between the stator assembly and the first flywheel rotor 1 and the second flywheel rotor 1, an intermediate cavity is formed between the first flywheel rotor 1 and the second flywheel rotor 1, and the pair of intermediate permanent magnet rings are respectively set on the first flywheel rotor 1 and the second flywheel rotor 1.

[0026] In this embodiment, slots are formed on the end faces of both the first flywheel rotor 1 and the second flywheel rotor 1. A mounting slot is formed on one side of the first flywheel rotor 1 and the second flywheel rotor 1 opposite to the housing, and an abutment slot is formed on the adjacent side of the first flywheel rotor 1 and the second flywheel rotor 1. This allows the stator assembly and permanent magnet assembly to be installed within the slots formed on the first flywheel rotor 1 and the second flywheel rotor 1, avoiding the large air gap length common in traditional coreless stator flywheel energy storage systems. This effectively reduces the standby loss of the flywheel energy storage system and improves its energy conversion efficiency. The paired intermediate permanent magnet rings include a first intermediate permanent magnet ring 3 and a second intermediate permanent magnet ring 5. The first intermediate permanent magnet ring 3 is disposed on the first flywheel rotor 1, and the second intermediate permanent magnet ring 5 is disposed on the second flywheel rotor 1. The paired abutment rings include a first abutment ring 10 and a second abutment ring 11. The first abutment ring 10 is disposed on the first flywheel rotor 1 and abuts against the first intermediate permanent magnet ring 3. The second abutment ring 11 is disposed on the second flywheel rotor 1 and abuts against the second intermediate permanent magnet ring 5.

[0027] See Figure 1 and Figure 5 The housing includes an upper end cover 8, a lower end cover 13, and a housing 15; the upper end cover 8 and the lower end cover 13 are detachably mounted on the housing 15, and a stator groove is provided on the central axis of the housing 15 to install and snap onto the stator located in the intermediate cavity.

[0028] like Figure 4 and Figure 5As shown, the stator assembly includes a first stator 9, a second stator 12, and an intermediate stator 4. The first stator 9 is fixedly mounted on the upper end cover 8 and located in the mounting slot of the first flywheel rotor 1. A first permanent magnet ring 2 is located between the first stator 9 and the first flywheel rotor 1. The second stator 12 is fixedly mounted on the lower end cover 13 and located in the mounting slot of the second flywheel rotor 1. A second permanent magnet ring 6 is located between the second stator 12 and the second flywheel rotor 1. The intermediate stator 4 is fixedly mounted in the stator slot and located in the intermediate cavity. Pairs of intermediate permanent magnet rings are located on both sides of the intermediate stator 4, and are located between the intermediate stator 4 and the first flywheel rotor 1, and between the intermediate stator 4 and the second flywheel rotor 1, respectively. The intermediate cavity also includes pairs of abutment rings, which are respectively mounted on the opposite sides of the first flywheel rotor 1 and the second flywheel rotor 1. The abutment rings facing the shaft core abut against the intermediate permanent magnet rings to increase the rated speed of the flywheel rotor 1.

[0029] In this embodiment, the flywheel energy storage system, based on the mechanical property of permanent magnets being "compressive but not tensile," sets a first permanent magnet ring 2 and a second permanent magnet ring 6 in the mounting slots of the flywheel rotors 1 at both ends. When the flywheel rotor 1 rotates at high speed, the permanent magnets are subjected to inward compressive stress from the flywheel rotor 1, thereby effectively increasing the rated speed of the flywheel rotor 1 and increasing its energy storage capacity. Similarly, the intermediate permanent magnet ring, through its abutment ring configuration, subjects the intermediate permanent magnet to inward compressive stress, thus allowing the intermediate permanent magnet ring and the first and second permanent magnet rings 2 and 6 at both ends to work together, effectively increasing the rated speed of the flywheel rotor 1 and its energy storage capacity. Furthermore, the first permanent magnet ring 2, the second permanent magnet ring 6, and the intermediate permanent magnet ring all include multiple permanent magnets, which are arranged sequentially to form a permanent magnet ring. The permanent magnets of the first permanent magnet ring 2, the second permanent magnet ring 6, and the intermediate permanent magnet ring that are adjacent in the circumferential direction have opposite magnetic poles; and the permanent magnets of the paired intermediate permanent magnet rings that are located in the same vertical plane in the vertical direction have the same magnetic poles. That is, the corresponding permanent magnets of the first intermediate permanent magnet ring 3 and the second intermediate permanent magnet ring 5 have the same magnetic poles in the vertical direction, and the permanent magnets of the first intermediate permanent magnet ring 3 and the second intermediate permanent magnet ring 5 that are adjacent in the circumferential direction have opposite magnetic poles.

[0030] like Figure 5 As shown, the housing also includes an upper mechanical bearing 7 and a lower mechanical bearing 14; the upper cover 8 and the lower cover 13 are connected to the shaft core through the upper mechanical bearing 7 and the lower mechanical bearing 14, respectively. In a preferred embodiment, the first stator 9, the second stator 12 and the intermediate stator 4 each include a non-magnetic and non-conductive stator support and an armature winding, with the armature winding fixedly mounted on the stator support.

[0031] In this embodiment, the flywheel energy storage system uses mechanical bearings to fix and support the shaft core, thereby effectively supporting the rotation of the rotor 1, reducing the coefficient of friction during the rotor 1's movement, and ensuring its rotational accuracy. Furthermore, the first stator 9, the second stator 12, and the intermediate stator 4 all employ non-magnetic and non-conductive stator supports, further eliminating stator core losses, improving the energy conversion efficiency of the flywheel energy storage system, and making the motor operation more stable.

[0032] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components; and they can also refer to a "transmission connection," that is, a power connection through various suitable methods such as belt drive, gear drive, or sprocket drive. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

Claims

1. A high-power flywheel energy storage device, characterized in that, The high-power flywheel energy storage device includes: a rotor, a stator assembly, a housing, and a permanent magnet assembly; The rotor includes a first flywheel rotor and a second flywheel rotor and a shaft core. The first flywheel rotor and the second flywheel rotor are coaxially arranged on the shaft core and the first flywheel rotor, the second flywheel rotor and the shaft core are integrally formed. The stator assembly is arranged between the rotor and the housing, and the permanent magnet assembly is arranged between the rotor and the stator assembly.

2. The high-power flywheel energy storage device according to claim 1, characterized in that, The permanent magnet assembly includes a first permanent magnet ring, a second permanent magnet ring, and a pair of intermediate permanent magnet rings; Both the first and second flywheel rotors have paired mounting slots. The stator assembly is located in the mounting slots and connected to the housing. The first and second permanent magnet rings are both disposed in the mounting slots and are located between the stator assembly and the first and second flywheel rotors. An intermediate cavity is formed between the first and second flywheel rotors. The paired intermediate permanent magnet rings are respectively disposed on the first and second flywheel rotors.

3. The high-power flywheel energy storage device according to claim 2, characterized in that, The housing includes an upper end cover, a lower end cover, and a housing. Both the upper and lower end caps are detachably mounted on the housing. A stator slot is provided on the central axis of the housing to install and engage the stator located in the intermediate cavity.

4. The high-power flywheel energy storage device according to claim 2, characterized in that, The stator assembly includes a first stator, a second stator, and an intermediate stator; The first stator is fixedly disposed on the upper end cover and located in the mounting groove of the first flywheel rotor. The first permanent magnet ring is located between the first stator and the first flywheel rotor. The second stator is fixedly disposed on the lower end cover and located in the mounting groove of the second flywheel rotor. The second permanent magnet ring is located between the second stator and the second flywheel rotor. The intermediate stator is fixedly disposed in the stator groove and located in the intermediate cavity. Pairs of intermediate permanent magnet rings are located on both sides of the intermediate stator and are located between the intermediate stator and the first flywheel rotor, and between the intermediate stator and the second flywheel rotor, respectively.

5. The high-power flywheel energy storage device according to claim 4, characterized in that, The intermediate cavity also includes a pair of abutment rings, which are respectively disposed on the opposite side of the first flywheel rotor and the second flywheel rotor. The side of the abutment ring facing the shaft core abuts against the intermediate permanent magnet ring to increase the rated speed of the flywheel rotor.

6. The high-power flywheel energy storage device according to claim 5, characterized in that, The housing also includes an upper mechanical bearing and a lower mechanical bearing; the upper cover and the lower cover are respectively connected to the shaft core through the upper mechanical bearing and the lower mechanical bearing.

7. The high-power flywheel energy storage device according to claim 6, characterized in that, The first permanent magnet ring, the second permanent magnet ring, and the intermediate permanent magnet ring each include multiple permanent magnets, which are arranged one by one to form a permanent magnet ring.

8. The high-power flywheel energy storage device according to claim 7, characterized in that, In the first permanent magnet ring, the second permanent magnet ring, and the intermediate permanent magnet ring, the permanent magnets adjacent in the circumferential direction have opposite magnetic poles, and in the paired intermediate permanent magnet rings, the permanent magnets located in the same vertical plane in the vertical direction have the same magnetic poles.

9. The high-power flywheel energy storage device according to claim 8, characterized in that, The first stator, the second stator, and the intermediate stator each include a non-magnetic and non-conductive stator support and an armature winding, wherein the armature winding is fixedly mounted on the stator support.

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