Flywheel energy storage motor

Abstract

The utility model discloses a flywheel energy storage motor relates to electric energy storage technical field, including coaxial installation on a flywheel pivot flywheel mechanism and permanent magnet synchronous motor, the flywheel mechanism is including the flywheel casing for the outside package, flywheel pivot one end is through mechanical bearing with flywheel casing rotation connection, the other end extends out flywheel casing and connects permanent magnet synchronous motor, flywheel casing lower extreme outside is provided with axial permanent magnet repulsion magnetic levitation bearing, is used for supporting the self weight of flywheel pivot and offsets the axial displacement caused by high -speed rotation precession effect. The utility model provides a bearing system, has increased bearing system stability, and this bearing system adopts the cooperation design of axial permanent magnet repulsion magnetic levitation bearing and mechanical bearing, can support flywheel pivot self weight and offset simultaneously the axial displacement caused by high -speed rotation precession effect, improves overall system stability and operation reliability.

Description

Technical Field

[0001] This utility model relates to the field of electrical energy storage technology, specifically to a flywheel energy storage motor. Background Technology

[0002] With the rapid development of new energy technologies, energy storage technology has become a key field. Flywheel energy storage devices are widely used due to their advantages such as excellent dynamic performance, high charge-discharge cycles, long lifespan, and low maintenance. Existing flywheel energy storage devices mainly consist of a flywheel shaft, a permanent magnet synchronous motor, and a magnetic levitation bearing system. The motor rotor is coaxially arranged with the flywheel, but the significant difference between the outer diameter of the motor rotor and the outer diameter of the flywheel leads to a complex flywheel shaft structure, requiring a dedicated magnetic levitation bearing system design. The flywheel shaft typically operates at high speeds: radial magnetic levitation bearings can prevent eccentricity, but axial magnetic levitation bearings must simultaneously bear the weight of the flywheel shaft and cope with the axial displacement caused by precession during high-speed rotation. This often results in insufficient stability of the bearing system, failing to effectively counteract axial forces and affecting overall operational reliability. Furthermore, existing permanent magnet magnetic levitation bearings are susceptible to environmental temperature effects. Mainstream designs place them inside the side housing, leading to increased operating temperature, decreased bearing performance, and even the risk of demagnetization failure, further shortening the device's lifespan and increasing maintenance difficulty. Utility Model Content

[0003] The purpose of this invention is to provide a flywheel energy storage motor that solves the problem that when the flywheel shaft is running at high speed, the axial magnetic levitation bearing must simultaneously bear the weight of the flywheel shaft and cope with the axial displacement caused by the precession effect during high-speed rotation.

[0004] The present invention solves the above-mentioned technical problems through the following technical solution. The present invention includes: a flywheel mechanism and a permanent magnet synchronous motor coaxially mounted on a flywheel shaft. The flywheel mechanism includes a flywheel housing for external enclosure. One end of the flywheel shaft is rotatably connected to the flywheel housing through a mechanical bearing, and the other end extends out of the flywheel housing and is connected to the permanent magnet synchronous motor. An axial permanent magnet repulsive magnetic levitation bearing is provided on the lower outer side of the flywheel housing to support the weight of the flywheel shaft and counteract the axial displacement caused by the high-speed rotational precession effect. The axial permanent magnet repulsive magnetic levitation bearing includes a magnetic bearing flange cover installed at the bottom of the flywheel housing. The magnetic bearing flange cover has an upper bearing flange portion and a lower bearing flange portion. The upper bearing flange portion is fixed to the bottom of the flywheel shaft, and the lower bearing flange portion is fixed to the upper surface of the magnetic bearing flange cover. The upper and lower bearing flange portions are each embedded with a flywheel axial magnetic levitation permanent magnet on the side closest to each other. The magnetic poles of the two sets of flywheel axial magnetic levitation permanent magnets on the side closest to each other have the same polarity, so as to generate a repulsive force to support the weight of the flywheel mechanism.

[0005] Preferably, the flywheel mechanism further includes a flywheel device fixed to the flywheel shaft, the flywheel device being a solid metal ring block.

[0006] Preferably, the flywheel housing includes a lower flywheel end cover, an upper flywheel end cover, and a side shell. The lower flywheel end cover, the upper flywheel end cover, and the side shell are fixedly connected by bolts, and the axial permanent magnet repulsive magnetic levitation bearing is detachably installed outside the lower flywheel end cover.

[0007] Preferably, the permanent magnet synchronous motor includes a motor housing, a motor stator, and a motor rotor; The motor housing is fixed to the upper surface of the flywheel housing, the motor stator is fixed to the inner wall of the motor housing, and the motor rotor is fixed to the extension end of the flywheel shaft.

[0008] Preferably, the motor stator includes a motor stator core and stator windings wound on the motor stator core; The motor rotor includes at least two axially connected motor rotor cores, a rotor permanent magnet installed in the inner hole of the motor rotor core, and a rotor end plate fixed to the outer end of the motor rotor core. Both motor rotor cores are fixed to the flywheel shaft.

[0009] Preferably, the other end of the flywheel shaft is rotatably connected to the motor housing via a mechanical bearing, and the mechanical bearing has an O-ring structure inside.

[0010] Preferably, the magnetic bearing flange cover is made of a non-ferromagnetic material.

[0011] Preferably, the upper part and the lower part of the bearing flange are made of ferromagnetic material.

[0012] Preferably, an axial electromagnetic bearing and a sensor for measuring the distance are provided between the flywheel upper end cover and the flywheel assembly to actively control the axial displacement of the flywheel shaft.

[0013] Preferably, the flywheel axial magnetic levitation permanent magnet has a double-layer structure, including an outer ring permanent magnet and an inner ring permanent magnet, to improve load-bearing capacity and enhance system stability.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows: 1. This utility model provides a bearing system that increases the stability of the bearing system. The bearing system adopts a design that combines an axial permanent magnet repulsive magnetic levitation bearing with a mechanical bearing. It can simultaneously support the weight of the flywheel shaft and counteract the axial displacement caused by the high-speed precession effect, thereby improving the overall system stability and operational reliability. 2. This utility model places the axial permanent magnet repulsive magnetic levitation bearing outside the flywheel housing, avoiding the influence of the internal high temperature environment, effectively preventing the permanent magnet from demagnetizing and failing, and greatly improving the bearing performance and service life. 3. To reduce the size of the flywheel energy storage motor and lower the maintenance difficulty, the flywheel device is arranged coaxially with the permanent magnet synchronous motor rotor, and the axial permanent magnet repulsive magnetic levitation bearing is fixed to the lower end cover of the flywheel through a separate flange end cover. This improves the space utilization of the flywheel device and reduces the assembly and maintenance difficulty.

[0015] 4. The structural design of this utility model facilitates bolt fixing and disassembly, reduces assembly and maintenance difficulty, reduces subsequent engineering maintenance costs, and improves the engineering applicability of the device. Attached Figure Description

[0016] Figure 1 A half-sectional view of a flywheel energy storage motor provided for an embodiment of this utility model; Figure 2 for Figure 1 A schematic diagram of a three-dimensional half-section of a permanent magnet synchronous motor. Figure 3 for Figure 1 Schematic diagram of the bottom plane structure of a medium-sized permanent magnet synchronous motor; Figure 4 This is a schematic diagram of a half-section of an axial permanent magnet repulsive magnetic levitation bearing. Figure 5 for Figure 1 Schematic diagram of a half-section of the lower end cover of the flywheel; Figure 6 This is a bottom view of a single-layer axial permanent magnet repulsive magnetic levitation bearing. Figure 7 This is a bottom view of a double-layer axial permanent magnet repulsive magnetic levitation bearing.

[0017] The numbers in the image represent: 1-Axial permanent magnet repulsive magnetic levitation bearing; 101-Upper part of bearing flange; 102-Magnetic bearing flange cover; 103-Flywheel axial magnetic levitation permanent magnet; 104-Lower part of bearing flange; 2-Mechanical bearing; 301-Lower end cover of flywheel; 302-Upper end cover of flywheel; 4-Side shell; 5-Flywheel assembly; 6-Flywheel shaft; 7-Permanent magnet synchronous motor; 701-Upper end cover of motor; 702-Rotor core of motor; 703-Stator core of motor; 704-Motor housing; 705-Stator winding; 706-Slotted bearing chamber; 707-Rotor end plate; 708-Rotor permanent magnet. Detailed Implementation

[0018] The above-mentioned and other technical features and advantages of this utility model will be described in more detail below with reference to the accompanying drawings.

[0019] Example 1: This embodiment provides a technical solution: a flywheel energy storage motor, such as... Figure 1 , Figure 4 , Figure 6 as well as Figure 7 As shown, it includes a flywheel mechanism and a permanent magnet synchronous motor 7 mounted on one side of the flywheel mechanism. The flywheel mechanism and the permanent magnet synchronous motor 7 are mounted on a flywheel shaft.

[0020] The flywheel mechanism includes a flywheel assembly 5, which is a solid metal circular ring block that is fastened to a flywheel shaft 6 by a threaded component. The flywheel shaft 6 has a stepped overall shape, which facilitates the positioning of the flywheel assembly and the structural layout of the rotor.

[0021] To ensure the safety performance of the flywheel device 5, it is equipped with a flywheel housing that fully encloses it. The flywheel housing includes a lower flywheel cover 301, an upper flywheel cover 302, and a side shell 4 located between the lower flywheel cover 301 and the upper flywheel cover 302. The lower flywheel cover 301, the upper flywheel cover 302, and the side shell 4 are all fixed to each other with bolts to facilitate future maintenance and disassembly.

[0022] One end of the flywheel shaft 6 is connected to the flywheel device 5 and the lower end cover 301 of the flywheel through the mechanical bearing 2. The other end extends through the upper end cover 302 of the flywheel. The permanent magnet synchronous motor 7 is mounted on the upper end cover 302 of the flywheel and is located at one end of the flywheel shaft 6.

[0023] The axial permanent magnet repulsive magnetic levitation bearing 1 is used to support the flywheel shaft 6 and the flywheel lower end cover 301. The upper and lower surfaces of the axial permanent magnet repulsive magnetic levitation bearing 1 form a suspension gap to support the weight of the flywheel mechanism.

[0024] The flywheel axial permanent magnet repulsive magnetic levitation bearing 1 includes: a magnetic bearing flange cover 102, an upper bearing flange portion 101, a lower bearing flange portion 104, and two sets of flywheel axial magnetic levitation permanent magnets 103. The upper bearing flange portion 101 and the lower bearing flange portion 104 are made of ferromagnetic materials. The magnetic bearing flange cover 102 is installed on the lower end cover 301 of the flywheel by bolts and is made of non-ferromagnetic materials to reduce magnetic leakage and loss. The lower surface of the lower bearing flange portion 104 contacts and is fixedly connected to the upper surface of the magnetic bearing flange cover 102. The upper bearing flange portion 101 contacts and is fixedly connected to the bottom of the flywheel shaft 6. An air gap is formed between the upper surface of the lower bearing flange portion 104 and the lower surface of the upper bearing flange portion 101, which generates a magnetic force along the positive Z-axis on the flywheel mechanism and the motor rotor, realizing the mass unloading of the energy storage flywheel mechanism and the motor rotor.

[0025] Two sets of flywheel axial magnetic levitation permanent magnets 103 are arranged in a circle. The two sets of flywheel axial magnetic levitation permanent magnets 103 are respectively embedded in the upper part 101 and the lower part 104 of the bearing flange. The two sets of flywheel axial magnetic levitation permanent magnets 103 are set opposite to each other. The magnetic poles on the side of the two sets of flywheel axial magnetic levitation permanent magnets 103 that are close to each other are the same, so they generate a mutual repulsive force, which plays a role in supporting the weight of the flywheel mechanism.

[0026] The flywheel shaft 6 uses the cooperation of axial permanent magnet repulsive magnetic levitation bearing 1 and mechanical bearing 2. The gravity of the flywheel mechanism itself can be offset by the repulsive force that is reduced due to the increase in air gap of the upper part 101 and the lower part 104 of the bearing flange of the flywheel axial permanent magnet repulsive magnetic levitation bearing 1 caused by the precession effect.

[0027] The axial permanent magnet repulsive magnetic levitation bearing 1 is placed outside the flywheel body and is not affected by the heat generated by the permanent magnet synchronous motor 7 and the flywheel device 5, so there is no risk of demagnetization.

[0028] Furthermore, such as Figure 7 As shown, with the increase of the motor rotor mass, the flywheel axial magnetic levitation permanent magnet 103 can be designed as a double layer, namely an outer ring of permanent magnets and an inner ring of permanent magnets, which greatly improves the load-bearing capacity of the axial permanent magnet repulsion magnetic levitation bearing.

[0029] Furthermore, an axial electromagnetic bearing can be installed between the lower side of the flywheel upper cover 302 and the upper side of the flywheel device 5, and a sensor for measuring the distance between the flywheel upper cover 302 and the flywheel device 5 can be installed on the flywheel upper cover 302 to actively control the axial movement amplitude of the flywheel shaft 6, improve the dynamic stability of the motor rotor, and further improve the mass and speed of the motor rotor, thereby increasing the maximum energy storage.

[0030] An O-ring structure is added inside the mechanical bearing 2, which allows the inner and outer rings of the mechanical bearing 2 to float up and down simultaneously. When the flywheel shaft 6 undergoes precession and moves up and down, the mechanical bearing 2 can follow the flywheel shaft 6 to make small displacements. Therefore, the mechanical bearing 2 does not bear a large axial force, which increases the stability of the bearing system.

[0031] Example 2: This embodiment is a further optimization based on Embodiment 1. The parts that are the same as those described above will not be repeated here. Figures 2 to 5 As shown, to further better realize the present invention, the following configuration is specifically adopted: The permanent magnet synchronous motor 7 in this embodiment includes a motor housing 704 connected to the upper surface of the flywheel upper end cover 302. A motor stator core 703 is installed on the inner wall of the motor housing 704. A stator winding 705 is wound on the motor stator core 703. The motor stator core 703 and the stator winding 705 together form the motor stator.

[0032] Two motor rotor cores 702 are fixed on the flywheel shaft 6. The two motor rotor cores 702 are axially connected and in contact. The segmented design of the motor rotor cores 702 effectively solves the unbalanced harmonic response caused by the motor at high speeds. Both motor rotor cores 702 have internal mounting holes, and a rotor permanent magnet 708 is installed in both mounting holes. Rotor end plates 707 are fixed to the outer ends of both motor rotor cores 702 to seal the ends of the rotor permanent magnet 708 and the motor rotor cores 702. The motor rotor cores 702, rotor end plates 707, and rotor permanent magnets 708 constitute the motor rotor.

[0033] The flywheel shaft 6 is rotatably connected to the upper motor cover 701 and the lower flywheel cover 301 of the motor housing 704 via mechanical bearings 2 at both ends. Specifically, slotted bearing chambers 706 are provided in the center of both the upper motor cover 701 and the lower flywheel cover 301. The slotted bearing chambers 706 are used to install the mechanical bearings 2, so that both ends of the flywheel shaft 6 and the mechanical bearings 2 are embedded in the upper motor cover 701 and the lower motor cover 301, with an air gap between the flywheel shaft 6 and the mechanical bearings 2. The flywheel shaft 6 is connected to the motor rotor core 702 and the flywheel assembly 5 by interference fit.

[0034] The above description is merely a preferred embodiment of the present utility model and is illustrative rather than restrictive. Those skilled in the art will understand that many changes, modifications, and even equivalents can be made within the spirit and scope defined by the claims of the present utility model, all of which will fall within the protection scope of the present utility model.

Claims

1. A flywheel energy storage motor, characterized in that, It includes a flywheel mechanism and a permanent magnet synchronous motor (7) coaxially mounted on a flywheel shaft (6). The flywheel mechanism includes a flywheel housing for external enclosure. One end of the flywheel shaft (6) is rotatably connected to the flywheel housing via a mechanical bearing (2), and the other end extends out of the flywheel housing and is connected to the permanent magnet synchronous motor (7). An axial permanent magnet repulsive magnetic levitation bearing (1) is provided on the lower outer side of the flywheel housing to support the weight of the flywheel shaft (6) and counteract the axial displacement caused by the high-speed rotational precession effect. The axial permanent magnet repulsive magnetic levitation bearing (1) includes a magnetic bearing flange cover (102) installed at the bottom of the flywheel housing. The magnetic bearing flange cover (102) is provided with an upper bearing flange part (101) and a lower bearing flange part (104). The upper bearing flange part (101) is fixed to the bottom of the flywheel shaft (6), and the lower bearing flange part (104) is fixed to the upper surface of the magnetic bearing flange cover (102). The upper bearing flange part (101) and the lower bearing flange part (104) are both embedded with flywheel axial magnetic levitation permanent magnets (103) on the side that are close to each other. The magnetic poles of the two sets of flywheel axial magnetic levitation permanent magnets (103) on the side that are close to each other have the same polarity.

2. The flywheel energy storage motor as described in claim 1, characterized in that, The flywheel mechanism also includes a flywheel device (5) fixed on the flywheel shaft (6), and the flywheel device (5) is a solid metal ring block.

3. The flywheel energy storage motor as described in claim 1 or 2, characterized in that, The flywheel housing includes a lower flywheel cover (301), an upper flywheel cover (302), and a side shell (4). The lower flywheel cover (301), the upper flywheel cover (302), and the side shell (4) are fixedly connected by bolts. The axial permanent magnet repulsive magnetic levitation bearing (1) is disassembled and installed outside the lower flywheel cover (301).

4. The flywheel energy storage motor as described in claim 1, characterized in that, The permanent magnet synchronous motor (7) includes a motor housing (704), a motor stator, and a motor rotor; The motor housing (704) is fixed to the upper surface of the flywheel housing, the motor stator is fixed to the inner wall of the motor housing (704), and the motor rotor is fixed to the extension end of the flywheel shaft (6).

5. The flywheel energy storage motor as described in claim 4, characterized in that, The motor stator includes a motor stator core (703) and a stator winding (705) wound on the motor stator core (703); The motor rotor includes at least two axially connected motor rotor cores (702), a rotor permanent magnet (708) installed in the inner hole of the motor rotor core (702), and a rotor end plate (707) fixed to the outer end of the motor rotor core (702). Both motor rotor cores (702) are fixed to the flywheel shaft (6).

6. The flywheel energy storage motor as described in claim 5, characterized in that, The other end of the flywheel shaft (6) is rotatably connected to the motor housing (704) via a mechanical bearing (2), and the mechanical bearing (2) is provided with an O-ring structure inside.

7. The flywheel energy storage motor as described in claim 1, characterized in that, The magnetic bearing flange cover (102) is made of a non-ferromagnetic material.

8. The flywheel energy storage motor as described in claim 1, characterized in that, The upper part (101) and the lower part (104) of the bearing flange are made of ferromagnetic material.

9. The flywheel energy storage motor as described in claim 3, characterized in that, An axial electromagnetic bearing and a sensor for measuring the distance are provided between the flywheel upper end cover (302) and the flywheel device (5) for actively controlling the axial displacement of the flywheel shaft (6).

10. The flywheel energy storage motor as described in claim 1, characterized in that, The flywheel axial magnetic levitation permanent magnet (103) has a double-layer structure, consisting of an outer ring permanent magnet and an inner ring permanent magnet, in order to improve load-bearing capacity and enhance system stability.

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