High-integration-level flywheel energy storage system based on strong magnetism gathering type stator permanent magnet type axial flux motor

Abstract

The invention discloses a high-integration flywheel energy storage system based on a strong magnetism gathering type stator permanent magnet axial flux motor, and relates to the field of flywheel energy storage systems. The problems that in the prior art, a permanent magnet of an axial flux motor is installed on a rotor, when the motor is heated, the rotor is difficult to cool, and the permanent magnet is prone to demagnetization are solved. The system comprises a strong magnetism gathering type stator permanent magnet type axial magnetic flux flywheel motor, a high-integration-level hybrid magnetic suspension bearing, an integrated flywheel rotor and the like. The strong magnetism gathering type stator permanent magnet axial magnetic flux flywheel motor comprises a stator and a rotor, and a spiral cooling water channel is arranged in the stator. The high-integration-level hybrid magnetic suspension bearing comprises a radial magnetic suspension bearing and an axial magnetic suspension shaft and is divided into a rotating part and a static part, and the static part and a stator in the strong magnetism gathering type stator permanent magnet type axial magnetic flux flywheel motor are integrated into a whole. The rotating part and a rotor of the strong magnetism gathering type stator permanent magnet type axial magnetic flux flywheel motor are embedded in the flywheel rotor, and the rotating part and the flywheel rotor jointly form an integrated flywheel rotor.

Description

Technical Field

[0001] The present invention relates to the technical field of flywheel energy storage systems, and in particular to a highly integrated flywheel energy storage system based on a strong magnetic concentration type stator permanent magnet type axial flux motor. Background Art

[0002] With the rapid growth of the number of cars, energy shortages and environmental pollution problems are becoming increasingly prominent, and energy conservation and emission reduction have become important demands in the current automotive field. As one of the effective means to reduce environmental pollution and save oil resources, electric vehicles have been regarded as an important way to solve the energy crisis and promote the sustainable development of the automotive industry. However, the endurance problem restricts the further development of electric vehicles. The flywheel energy storage system breaks through the limitations of chemical batteries and has the advantages of no pollution, high energy conversion efficiency and power density, and long cycle life. Applying it to the regenerative braking system of electric vehicles can effectively improve the endurance of electric vehicles, which is an important way to help my country achieve low-carbon and energy transformation goals.

[0003] However, due to the internal space limitations of electric vehicles and the requirements of the vehicle for the energy density and weight of the flywheel energy storage system, the flywheel energy storage for electric vehicles requires a compact structure and high energy density index. As the core component of the flywheel energy storage system, the performance of the high-speed flywheel motor directly affects the quality of the flywheel energy storage system. The axial flux motor has the advantages of compact axial size, high efficiency and high power density, and has broad application prospects in the flywheel energy storage system of electric vehicles.

[0004] However, the permanent magnets of traditional axial flux motors are installed on the rotor. When the motor heats up, it is difficult to cool the rotor, which is prone to failures such as permanent magnet demagnetization. Therefore, there are still many problems that need to be solved in the flywheel energy storage system for electric vehicles, which to some extent limits its engineering application. Summary of the invention

[0005] The present invention aims to solve the problem that in the prior art, the permanent magnet of the axial flux motor is installed on the rotor. When the motor heats up, the rotor is difficult to cool, and permanent magnet demagnetization and other faults are prone to occur. In addition, the flywheel energy storage system for electric vehicles requires high stability, high integration and high energy density. To solve the above technical problems, the present invention is implemented through the following technical solutions:

[0006] Solution 1: The present invention proposes a highly integrated flywheel energy storage system based on a strong magnetic stator permanent magnet axial flux motor, wherein the highly integrated flywheel energy storage system comprises a strong magnetic stator permanent magnet axial flux flywheel motor, a highly integrated hybrid magnetic suspension bearing, and an integrated flywheel rotor;

[0007] The strong magnetic concentration stator permanent magnet axial magnetic flux flywheel motor comprises two stators and a rotor, and a spiral cooling water channel is arranged inside the stator;

[0008] The highly integrated hybrid magnetic suspension bearing includes a radial magnetic suspension bearing and an axial magnetic suspension shaft, which is divided into a rotating part and a stationary part. The stationary part is integrated with the stator of the strong magnetic concentration stator permanent magnet type axial magnetic flux flywheel motor, and the rotating part is integrated with the rotor of the strong magnetic concentration stator permanent magnet type axial magnetic flux flywheel motor, and together they form an integrated flywheel rotor.

[0009] Furthermore, a preferred embodiment is provided, wherein the stator comprises windings, excitation permanent magnets, magnetizing permanent magnets, a stator core and a cooling water channel, and the excitation permanent magnets and magnetizing permanent magnets transfer heat in the cooling water channel through the stator core.

[0010] Furthermore, a preferred embodiment is provided, wherein the excitation permanent magnet is embedded in the stator teeth of the iron core.

[0011] Furthermore, a preferred embodiment is provided, in which the magnetizing permanent magnets are attached to the stator tooth pole shoes of the iron core.

[0012] Furthermore, a preferred embodiment is provided, in which the magnetization method of two adjacent excitation permanent magnets is a tangential magnetization method with opposite magnetization directions.

[0013] Furthermore, a preferred embodiment is provided, in which the magnetization method of two adjacent magnetization permanent magnets is a radial magnetization method with opposite magnetization directions.

[0014] Furthermore, a preferred embodiment is provided, in which the direction of the magnetic field generated by the magnetizing permanent magnet is the same as the direction of the magnetic field generated by the exciting permanent magnet at the air gap.

[0015] Furthermore, a preferred embodiment is provided, wherein a spiral cooling water channel is provided in the stator core inside the stator.

[0016] Furthermore, a preferred embodiment is provided, wherein a non-magnetic and non-conductive coolant is passed into the cooling water channel.

[0017] Furthermore, a preferred embodiment is provided, wherein the rotor has neither permanent magnets nor windings.

[0018] The present invention is beneficial in that:

[0019] In the highly integrated flywheel energy storage system based on the strong magnetic stator permanent magnet axial flux motor described in the present invention, the rotor of the strong magnetic stator permanent magnet axial flux flywheel motor has neither permanent magnets nor windings, which increases the heat resistance of the motor while ensuring the mechanical strength.

[0020] The stator part of the strong magnetic concentration type stator permanent magnet type axial magnetic flux flywheel motor described in the present invention is equipped with a spiral water channel to improve the heat dissipation capacity of the system and solve the problem of excessive temperature rise caused by the concentration of heat sources in the stator part and the difficulty of heat dissipation in a vacuum operating environment.

[0021] The strong magnetic concentration type stator permanent magnet type axial magnetic flux flywheel motor described in the present invention is equipped with magnetizing permanent magnets at the stator tooth pole shoes to enhance the magnetic concentration effect and improve the air gap magnetic density and power density of the motor.

[0022] The hybrid magnetic suspension bearing of the present invention integrates the radial magnetic suspension bearing and the axial magnetic suspension bearing into one, thereby reducing the volume of the magnetic suspension bearing and improving the integration level.

[0023] The stator part of the hybrid magnetic suspension bearing described in the present invention is integrated with the stator part of the strong magnetic concentration type stator permanent magnet type axial magnetic flux flywheel motor, thereby improving the system integration.

[0024] The rotating part of the hybrid magnetic suspension bearing described in the present invention is integrated with the rotor part of the strong magnetic concentration stator permanent magnet axial flux flywheel motor and the high-speed flywheel rotor, thereby improving the system integration and increasing the space utilization.

[0025] The present invention is also applicable to the field of flywheel energy storage systems for electric vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the three-dimensional structure disassembly of a highly integrated flywheel energy storage system based on a strong magnetic concentration stator permanent magnet axial flux motor as described in the first embodiment.

[0027] Figure 2 It is a schematic diagram of the three-dimensional structure of the strong magnetic concentration stator permanent magnet axial flux flywheel motor described in the first embodiment.

[0028] Figure 3 This is a schematic diagram of the stator structure of a permanent magnet type axial flux switching flywheel motor with a strong magnetic concentration stator as described in the first embodiment.

[0029] Figure 4 This is a schematic diagram of the magnetization method described in the eleventh embodiment.

[0030] Figure 5 This is a schematic diagram of the magnetization principle described in the eleventh embodiment.

[0031] Figure 5 In the figure, (a) is the trend diagram of magnetic force lines of the excitation permanent magnet. (b) is the trend diagram of magnetic force lines of the magnetization permanent magnet.

[0032] Figure 6 This is a schematic diagram of the cooling water channel of the strong magnetic concentration stator permanent magnet axial flux flywheel motor described in the eleventh embodiment.

[0033] Figure 7 This is a schematic diagram of the structure of a highly integrated hybrid magnetic bearing according to the eleventh embodiment.

[0034] Figure 8 This is a schematic diagram of the integration of the stationary part of the hybrid magnetic bearing and the stator part of the strong magnetic concentration type stator permanent magnet type axial flux flywheel motor described in the eleventh embodiment.

[0035] Fig. 9 This is a schematic diagram of the integrated flywheel rotor structure described in embodiment eleven.

[0036] In the figure, there is a strong magnetic stator permanent magnet axial flux flywheel motor 1, a highly integrated hybrid magnetic bearing 2, an integrated flywheel rotor 3, a vacuum chamber 4, a protective bearing 5, a stator 11, a rotor 12, a winding 111, an excitation permanent magnet 112, a magnetization permanent magnet 113, an iron core 114, a cooling water channel 115, a radial magnetic bearing 21, an axial magnetic bearing 22, a stationary part 23, and a rotating part 24. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the implementation methods of the present application clearer, the technical solutions in the implementation methods of the present application will be clearly and completely described below in conjunction with the drawings in the implementation methods of the present application. Obviously, the described implementation methods are only part of the implementation methods of the present application, not all of the implementation methods.

[0038] Embodiment 1: This embodiment provides a highly integrated flywheel energy storage system based on a strong magnetic stator permanent magnet axial flux motor, wherein the highly integrated flywheel energy storage system comprises a strong magnetic stator permanent magnet axial flux flywheel motor 1, a highly integrated hybrid magnetic suspension bearing 2, and an integrated flywheel rotor 3;

[0039] The strong magnetic concentration type stator permanent magnet type axial magnetic flux flywheel motor 1 comprises two stators 11 and a rotor 12, and a spiral cooling water channel 115 is arranged inside the stator 11;

[0040] The highly integrated hybrid magnetic suspension bearing 2 includes a radial magnetic suspension bearing 21 and an axial magnetic suspension shaft 22, which is divided into a rotating part 23 and a stationary part 24. The stationary part 24 is integrated with the stator 11 in the strong magnetic concentration stator permanent magnet type axial magnetic flux flywheel motor, and the rotating part 23 is integrated with the rotor 12 of the strong magnetic concentration stator permanent magnet type axial magnetic flux flywheel motor 1, and together they form an integrated flywheel rotor 3.

[0041] Embodiment 2. This embodiment further limits the highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor described in embodiment 1. The stator 11 includes a winding 111, an excitation permanent magnet 112, a magnetization permanent magnet 113, a stator core 114 and a cooling water channel 115. The excitation permanent magnet 112 and the magnetization permanent magnet 113 transfer the heat in the cooling water channel 115 through the stator core 114.

[0042] Embodiment 3: This embodiment further limits the highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor described in Embodiment 2, and the excitation permanent magnet 112 is embedded in the stator teeth of the iron core 114.

[0043] Embodiment 4: This embodiment further limits the highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor described in Embodiment 2, and the magnetizing permanent magnet 113 is attached to the stator tooth pole shoe of the iron core 114.

[0044] Embodiment 5: This embodiment further limits the highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor described in embodiment 2. The magnetization method of two adjacent excitation permanent magnets 112 is a tangential magnetization method with opposite magnetization directions.

[0045] Embodiment 6: This embodiment further limits the highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor described in embodiment 2. The magnetization method of two adjacent magnetizing permanent magnets 113 is a radial magnetization method with opposite magnetization directions.

[0046] Embodiment 7. This embodiment is a further limitation of the highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor described in embodiment 3 or 4. The direction of the magnetic field generated by the magnetizing permanent magnet 113 is the same as the direction of the magnetic field generated by the excitation permanent magnet 112 at the air gap.

[0047] Embodiment 8: This embodiment further limits the highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor described in Embodiment 2. A spiral cooling water channel 115 is provided in the stator core 114 inside the stator 11.

[0048] Embodiment 9: This embodiment further limits the highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor described in embodiment 8, and a spiral cooling water channel 115 is provided in the stator core 114 inside the stator 11.

[0049] Embodiment 10: This embodiment further limits the highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor described in embodiment 1. The rotor 12 has no permanent magnets and no windings.

[0050] Implementation 11: This implementation proposes an example, which is used to explain the above-mentioned implementations 1 to 8. The specific example is as follows:

[0051] See also Figures 1 to 9 To describe this embodiment, the present invention proposes a new topology of a highly integrated flywheel energy storage system based on a strong magnetic stator permanent magnet axial flux motor, which mainly includes a strong magnetic stator permanent magnet axial flux flywheel motor, a highly integrated hybrid magnetic suspension bearing, an integrated flywheel rotor, a protective bearing and a vacuum chamber. The strong magnetic stator permanent magnet axial flux flywheel motor consists of two stators and a rotor, and a spiral water channel is provided inside the stator. The highly integrated hybrid magnetic suspension bearing consists of a radial magnetic suspension bearing and an axial magnetic suspension shaft, and mainly includes a stationary part and a rotating part. The stationary part is integrated with the stator part of the strong magnetic stator permanent magnet axial flux flywheel motor, and the rotating part is integrated with the rotor part of the strong magnetic stator permanent magnet axial flux flywheel motor and the high-speed flywheel rotor, together forming an integrated flywheel rotor structure.

[0052] By introducing magnetizing permanent magnets, the magnetic field concentration effect is enhanced, and the air gap magnetic flux density and power density of the system are improved. It is deeply integrated with the highly integrated hybrid magnetic suspension bearing and the integrated flywheel rotor to improve the system energy density and increase the space utilization. By equipping the iron core 114 of the strong magnetic concentration stator permanent magnet axial flux flywheel motor 1 with a spiral cooling water channel 115, the heat dissipation performance of the system is improved, the system is prevented from overheating, and the safe and reliable operation of the system is ensured.

[0053] refer to Figure 1 As shown, the highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor in the present invention includes a strong magnetic concentration stator permanent magnet axial flux flywheel motor 1, a highly integrated hybrid magnetic suspension bearing 2, an integrated flywheel rotor 3, a protective bearing 4 and a vacuum chamber 5.

[0054] refer to Figures 2 to 6As shown, the strong magnetic concentration type stator permanent magnet type axial flux flywheel motor 1 of the present invention is composed of two stators 11 and a rotor 12. The stator 11 mainly includes a winding 111, an excitation permanent magnet 112, a magnetizing permanent magnet 113, an iron core 114 and a cooling water channel 115. The excitation permanent magnet 112 is embedded in the stator teeth of the iron core 114, and the magnetizing permanent magnet is attached to the stator tooth pole shoe of the iron core 114. The two adjacent excitation permanent magnets 112 adopt a tangential magnetization method with opposite magnetization directions, and the two adjacent magnetizing permanent magnets 113 adopt a radial magnetization method with opposite magnetization directions. The excitation permanent magnet 112 and the magnetizing permanent magnet 113 are used in combination, so that the direction of the magnetic field generated by the magnetizing permanent magnet 113 is the same as the direction of the magnetic field generated by the excitation permanent magnet 11 at the air gap, and the magnetic fields of the two are superimposed, which plays a role in increasing the air gap magnetic field, and can effectively improve the power density of the motor. The stator core 114 is embedded with a cooling water channel 115, into which a non-magnetic and non-conductive coolant is passed. The coolant circulates in the cooling water channel 115, taking away the heat from the stator core 114 and directly transferring it to the cooling water channel 115 and the winding 111. The excitation permanent magnet 112 and the magnetization permanent magnet 113 are transferred to the cooling water channel 115 through the stator core, thereby achieving the purpose of cooling, and effectively solving the high temperature rise problem of the system caused by the concentrated heat source of the strong magnetic stator permanent magnet type axial flux flywheel motor and the difficulty of heat dissipation in a vacuum environment. The rotor 12 has neither permanent magnets nor windings, which effectively improves the mechanical strength of the motor and ensures the safe and stable operation of the motor.

[0055] refer to Figures 7 to 9 As shown, the highly integrated hybrid magnetic bearing 2 is composed of a radial magnetic bearing 21 and an axial magnetic bearing shaft 22, which can be divided into a rotating part 23 and a stationary part 24. The stationary part 24 is integrated with the stator part 11 of the strong magnetic stator permanent magnet axial flux flywheel motor, and the rotating part 23 and the rotor 12 of the strong magnetic stator permanent magnet axial flux flywheel motor 1 are embedded in the flywheel rotor, and together with the flywheel rotor, form an integrated flywheel rotor structure. The embedded partial magnetic bearing can not only provide energy as a part of the flywheel, but also provide bearing capacity as a part of the magnetic bearing. Therefore, the system volume is reduced and the system integration is improved.

[0056] Those skilled in the art will appreciate that the above are only preferred embodiments of the present invention, and the various embodiments of the present disclosure and / or the features described in the claims may be combined or combined in various ways, even if such combinations or combinations are not explicitly described in the present disclosure. It is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art may still modify the technical solutions described in the aforementioned embodiments, or perform equivalent substitutions on some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

[0057] Although preferred embodiments of the present invention have been described, additional changes and modifications may be made to these embodiments by those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A highly integrated flywheel energy storage system based on a strong magnetic stator permanent magnet axial flux motor, characterized in that: The highly integrated flywheel energy storage system comprises a strong magnetic concentration type stator permanent magnet type axial magnetic flux flywheel motor (1), a highly integrated hybrid magnetic suspension bearing (2), and an integrated flywheel rotor (3); The strong magnetic concentration type stator permanent magnet type axial magnetic flux flywheel motor (1) comprises two stators (11) and a rotor (12), wherein a spiral cooling water channel (115) is arranged inside the stator (11); The highly integrated hybrid magnetic suspension bearing (2) comprises a radial magnetic suspension bearing (21) and an axial magnetic suspension shaft (22), and is divided into a rotating part (23) and a stationary part (24), wherein the stationary part (24) is integrated with a stator (11) of a strong magnetic concentration type stator permanent magnet type axial magnetic flux flywheel motor, and the rotating part (23) is integrated with a rotor (12) of the strong magnetic concentration type stator permanent magnet type axial magnetic flux flywheel motor (1), and together they form an integrated flywheel rotor (3).

2. The highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor according to claim 1 is characterized in that: The stator (11) comprises a winding (111), an excitation permanent magnet (112), a magnetizing permanent magnet (113), a stator core (114) and a cooling water channel (115); the excitation permanent magnet (112) and the magnetizing permanent magnet (113) transfer heat in the cooling water channel (115) through the stator core (114).

3. The highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor according to claim 2 is characterized in that: The excitation permanent magnet (112) is embedded in the stator teeth of the iron core (114).

4. The highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor according to claim 2 is characterized in that: The magnetizing permanent magnet (113) is attached to the stator tooth pole shoe of the iron core (114).

5. The highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor according to claim 2 is characterized in that: The magnetization method of two adjacent excitation permanent magnets (112) is a tangential magnetization method with opposite magnetization directions.

6. The highly integrated flywheel energy storage system based on a strong magnetic concentration stator permanent magnet axial flux motor according to claim 2 is characterized in that: The magnetization method of two adjacent magnetization permanent magnets (113) is a radial magnetization method with opposite magnetization directions.

7. The highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor according to claim 3 or 4, characterized in that: The direction of the magnetic field generated by the magnetizing permanent magnet (113) is the same as the direction of the magnetic field generated by the exciting permanent magnet (112) at the air gap.

8. The highly integrated flywheel energy storage system based on a strong magnetic concentration stator permanent magnet axial flux motor according to claim 2 is characterized in that: A spiral cooling water channel (115) is provided in the stator iron core (114) inside the stator (11).

9. The highly integrated flywheel energy storage system based on the strong magnetic concentration stator permanent magnet axial flux motor according to claim 8 is characterized in that: A non-magnetic and non-conductive cooling liquid is introduced into the cooling water channel (115).

10. The highly integrated flywheel energy storage system based on a strong magnetic concentration stator permanent magnet axial flux motor according to claim 1 is characterized in that: The rotor (12) has neither permanent magnets nor windings.

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