Stator-isolated full magnetic suspension flywheel energy storage device
By using stator isolation and magnetic levitation technology, the problem of motor stator insulation in flywheel energy storage devices has been solved, achieving improved structural compactness and space utilization, enhancing insulation reliability and economy, and providing more cooling methods.
Patent Information
- Application Number
- CN202520303082.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-25
- Publication Date
- 2026-02-24
- Estimated Expiration
- 2035-02-25
AI Technical Summary
In existing flywheel energy storage devices, the motor stator has poor insulation performance under vacuum conditions, making it prone to breakdown. Furthermore, the compact structure and low space utilization result in high costs, complex processes, and difficulty in ensuring the stability of insulation performance.
The stator isolation structure isolates the flywheel rotor from the stator. The flywheel rotor is suspended by radial and axial magnetic levitation mechanisms, and a vacuum cavity is formed inside the stator. Combined with the design of the motor rotor and flywheel rotor, more cooling methods are provided and space utilization is improved.
It improves the insulation reliability and economy of flywheel energy storage devices, enhances structural compactness, provides more cooling methods, and improves space utilization and power density.
Smart Images
Figure CN223942540U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of flywheel energy storage technology, specifically a stator-isolated, fully magnetically levitated flywheel energy storage device. Background Technology
[0002] Flywheel energy storage has advantages such as high instantaneous power, long cycle life, low operating loss, environmental friendliness, and no geographical restrictions. As one of the most promising power storage technologies under the current dual-carbon background, it has been widely used.
[0003] Flywheel energy storage devices typically consist of a flywheel rotor, bearings, a motor, and a vacuum chamber. During operation, the entire vacuum chamber needs to be evacuated to a near-vacuum state to reduce wind-induced wear and tear caused by the high-speed rotation of the flywheel rotor. However, in the structure of flywheel energy storage devices, the flywheel rotor and motor are often housed within the same vacuum chamber. Under vacuum conditions, the insulation performance of the motor stator armature windings is significantly reduced. Without reinforced insulation, the windings are highly susceptible to breakdown and burnout. To address this issue, the industry commonly employs methods such as increasing the thickness of the armature winding insulation material or encapsulating the entire stator with epoxy resin to improve its insulation performance. However, these methods suffer from drawbacks such as complex manufacturing processes and poor economic efficiency. Furthermore, as the power rating and size of the motor increase, ensuring the stability of its insulation performance becomes increasingly difficult, and the cost is also substantial.
[0004] In addition, the structural design of flywheel energy storage devices often involves a motor rotor carrying a flywheel rotor, and space needs to be reserved for magnetic levitation bearings, resulting in poor overall structural compactness. Furthermore, the bottom flywheel occupies a large area, while the top motor is relatively small, leading to low space utilization. Utility Model Content
[0005] To address the shortcomings of existing technologies, this utility model provides a stator-isolated, fully magnetically levitated flywheel energy storage device. It has advantages such as improved device structure compactness and increased space utilization. It solves the problems of complex manufacturing processes and poor economic efficiency. Furthermore, as the power level of the motor increases and its size increases, it becomes increasingly difficult to ensure the stability of its insulation effect, and the cost is relatively high. In addition, existing flywheel energy storage devices have poor overall structural compactness, with a large footprint of the bottom flywheel and a small size of the top motor, resulting in low space utilization.
[0006] To achieve the goal of compact structure and improved space utilization of the above-mentioned lifting device, this utility model provides the following technical solution: a stator-isolated fully magnetically levitated flywheel energy storage device, including an isolated stator, a flywheel rotor suspended inside the isolated stator, radial magnetic levitation mechanisms fixedly connected to both the upper and lower ends of the isolated stator, axial magnetic levitation mechanisms fixedly connected to the opposite sides of the two radial magnetic levitation mechanisms, and protective bearings fixedly connected inside the magnetic levitation mechanisms.
[0007] Preferably, the isolation stator includes a motor housing, an iron core, a stator armature winding, and an isolation cover. The isolation cover is fixedly connected inside the motor housing, and an iron core is fixedly connected between the motor housing and the isolation cover. The iron core has stator slots, and the stator armature winding is wound in the stator slots.
[0008] Preferably, the radial magnetic levitation mechanism includes an upper radial magnetic levitation bearing, a housing, a lower radial magnetic levitation bearing, and a base. The housing and the base are respectively fixedly connected to the top and bottom of the motor housing. The upper radial magnetic levitation bearing is fixedly connected inside the housing, and the lower radial magnetic levitation bearing is fixedly connected inside the base. Both the upper and lower radial magnetic levitation bearings are U-shaped ferromagnetic rings, and both the upper and lower radial magnetic levitation bearings are equipped with excitation windings inside.
[0009] Preferably, the axial magnetic levitation mechanism includes an upper axial magnetic levitation bearing and a lower axial magnetic levitation bearing, which are arranged opposite to each other on the inner top wall and inner bottom wall of the motor housing.
[0010] Preferably, the flywheel rotor includes a flywheel, a permanent magnet, a magnetic shielding ring, a carbon fiber sheath, an upper shaft, and a lower shaft. The top and bottom of the flywheel are fixedly connected to the upper shaft and the lower shaft, respectively. An annular groove is formed on the outside of the flywheel, and a permanent magnet is placed in the annular groove. Magnetic shielding rings are placed at both the upper and lower ends of the permanent magnet. A carbon fiber sheath is fitted around the permanent magnet and the magnetic shielding rings.
[0011] Preferably, protective bearings are fixedly connected inside both the housing and the base, and the protective bearings are used to support the rotation of the flywheel rotor when the magnetic levitation mechanism fails.
[0012] Preferably, the upper radial magnetic levitation bearing and the lower radial magnetic levitation bearing are respectively fitted with an upper rotating shaft and a lower rotating shaft, and there is a first air gap between the upper radial magnetic levitation bearing and the upper rotating shaft, and there is a second air gap between the lower radial magnetic levitation bearing and the lower rotating shaft.
[0013] Preferably, the isolation cover is a non-magnetic sealing barrel with a "Z" shaped cross-section and screw holes on the upper and lower end faces for fixing and sealing.
[0014] Compared with the prior art, this utility model provides a stator-isolated fully magnetically levitated flywheel energy storage device, which has the following beneficial effects:
[0015] 1. This patent adopts a stator and flywheel cavity isolation structure, which solves the problem of stator armature winding insulation under vacuum in flywheel energy storage device, thereby improving the reliability and economy of the device.
[0016] 2. This patent adopts a stator isolation structure, making the stator self-contained and providing more possibilities for cooling methods, such as circulating oil spray cooling, thereby improving the power density of the device.
[0017] 3. This patent adopts a combination of motor rotor and flywheel rotor, embedding the motor rotor magnet into the flywheel, which improves the structural compactness of the flywheel energy storage device and greatly improves its space utilization. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the flywheel energy storage device proposed in this patent;
[0019] Figure 2 This is a schematic diagram of the isolation cover in the flywheel energy storage device proposed in this patent;
[0020] Figure 3 This is a cross-sectional view of the flywheel rotor in the flywheel energy storage device proposed in this patent;
[0021] Figure 4 This is a schematic diagram of another structure of the flywheel rotor in the flywheel energy storage device proposed in this patent;
[0022] Figure 5 This is a schematic diagram of the supporting base in the flywheel energy storage device proposed in this patent;
[0023] In the diagram: 1. Stator with isolation; 101. Motor housing; 102. Iron core; 103. Stator armature winding; 104. Isolation cover; 2. Flywheel rotor; 201. Flywheel; 202. Permanent magnet; 203. Magnetic isolation ring; 204. Carbon fiber sheath; 205. Upper shaft; 206. Lower shaft; 3. Axial magnetic levitation mechanism; 301. Upper axial magnetic levitation bearing; 302. Lower axial magnetic levitation bearing; 4. Magnetic levitation mechanism; 401. Upper radial magnetic levitation bearing; 402. Housing; 403. Lower radial magnetic levitation bearing; 404. Base; 5. Protective bearing. Detailed Implementation
[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0025] Please see Figure 1-5A stator-isolated fully magnetically levitated flywheel energy storage device includes an isolated stator 1. The isolated stator 1 includes a motor housing 101, an iron core 102, a stator armature winding 103, and an isolation cover 104. The isolation cover 104 is fixedly connected inside the motor housing 101. The isolation cover 104 is a non-magnetic sealed barrel with a "Z"-shaped cross-section and screw holes on the upper and lower ends for fixing and sealing. The isolation cover 104 is placed in the air gap between the stator and the flywheel rotor 2, and its thickness is slightly smaller than the air gap. It is assembled from top to bottom, and both the upper and lower ends are sealed with sealing rings and screws, making the stator's interior a self-contained cavity. The sealed cavity between the motor housing 101 and the isolation cover 104 is filled with cooling oil for oil spray circulation cooling. After the flywheel rotor 2 cavity is evacuated, the internal cavity of the stator remains at normal atmospheric pressure, and the stator armature winding 103 can operate normally without strengthening insulation.An iron core 102 is fixedly connected between the motor housing 101 and the isolation cover 104. The iron core 102 has stator slots, and a stator armature winding 103 is wound in the stator slots. The stator armature winding is supplied with three-phase alternating current to generate a rotating magnetic field that drives the flywheel rotor to store energy. A flywheel rotor 2 is suspended inside the isolation stator 1. The flywheel rotor 2 includes a flywheel 201, a permanent magnet 202, a magnetic shielding ring 203, a carbon fiber sheath 204, an upper shaft 205, and a lower shaft 206. The top and bottom of the flywheel 201 are respectively provided with shafts that fit the upper shaft 205 and the lower shaft 206. The flywheel 201 is equipped with an annular groove and screw holes. The flywheel 201 is fixedly connected to the upper rotating shaft 205 and the lower rotating shaft 206 via the annular groove, or the flywheel 201 is integrally formed with the upper rotating shaft 205 and the lower rotating shaft 206, improving rotor strength and stability. An annular groove is formed on the outside of the flywheel 201, and a permanent magnet 202 is placed inside the annular groove. The permanent magnet 202 forms a magnetic field in the air gap. The stator magnetic field drives the air gap magnetic field to rotate, simultaneously driving the flywheel 201 to rotate for energy storage. Magnetic shielding rings 203 are placed at both the upper and lower ends of the permanent magnet 202 to reduce the magnetic field density of the permanent magnet 202. To mitigate magnetic leakage, the permanent magnet 202 and the magnetic isolation ring 203 are externally fitted with a carbon fiber sheath 204. Radial magnetic levitation mechanisms 4 are fixedly connected to both the upper and lower ends of the isolation stator 1. The radial magnetic levitation mechanism 4 includes an upper radial magnetic levitation bearing 401, a housing 402, a lower radial magnetic levitation bearing 403, and a base 404. The housing 402 and base 404 are fixedly connected to the top and bottom of the motor housing 101, respectively. The upper radial magnetic levitation bearing 401 is fixedly connected inside the housing 402, and the lower radial magnetic levitation bearing 403 is fixedly connected inside the base 404. 3. Both the upper radial magnetic levitation bearing 401 and the lower radial magnetic levitation bearing 403 are U-shaped ferromagnetic rings, and both the upper radial magnetic levitation bearing 401 and the lower radial magnetic levitation bearing 403 are equipped with excitation windings. The upper rotating shaft 205 and the lower rotating shaft 206 are respectively adapted inside the upper radial magnetic levitation bearing 401 and the upper rotating shaft 205. There is a first air gap between the upper radial magnetic levitation bearing 401 and the upper rotating shaft 205, and there is a second air gap between the lower radial magnetic levitation bearing 403 and the lower rotating shaft 206. Their levitation force directly acts on the upper and lower rotating shafts.
[0026] Fix the lower radial magnetic levitation bearing 403 and the base 404 that supports the entire device. Adopt a cylindrical structure with a "匚" cross-section, and weld support ribs between the upper and lower planes to increase the support strength of the entire base 404. Axial magnetic levitation mechanisms 3 are fixedly connected to the opposite sides of the two radial magnetic levitation mechanisms 4. The axial magnetic levitation mechanism 3 includes an upper axial magnetic levitation bearing 301 and a lower axial magnetic levitation bearing 302. The upper axial magnetic levitation bearing 301 and the lower axial magnetic levitation bearing 302 are arranged opposite to each other on the inner top wall and the inner bottom wall of the motor housing 101. The upper axial magnetic levitation bearing 301 and the lower axial magnetic levitation bearing 302 are U-shaped ferromagnetic rings, in which excitation windings are placed. They are placed on the upper and lower end faces of the 201 flywheel and are structurally adapted to the isolation cover 104 in the isolation stator 1. They can be adjusted according to the installation position and structure of the isolation cover 104 to make the entire device more compact in space. A protection bearing 5 is fixedly connected inside the magnetic levitation mechanism 4, and protection bearings 5 are fixedly connected inside the housing 402 and the base 404. The protection bearing 5 is used to support the rotation of the flywheel rotor 2 when the magnetic levitation mechanism fails.
[0027] In summary, for this stator-isolated fully magnetic levitation flywheel energy storage device, by setting the iron core 102 and the stator armature winding 103, when the iron core 102 and the stator armature winding 103 are energized to generate magnetic force, a transverse magnetic force can be applied to the rotor 2. Through the interaction between the permanent magnet 202 and the magnetic force, the rotor 2 can be rotated. By setting the upper axial magnetic levitation bearing 301, the lower axial magnetic levitation bearing 302, the upper radial magnetic levitation bearing 401 and the lower radial magnetic levitation bearing 403, a longitudinal magnetic force can be applied to the rotor 2 to make it levitate inside the isolation cover 104. By setting the motor housing 101, a sealed cavity is formed between the motor housing 101 and the isolation cover 104, and the sealed cavity is pumped to a vacuum. The stator armature winding 103 is arranged inside the sealed cavity. The insulation problem of the stator armature winding 103 is solved under vacuum, improving the reliability and economy of the device. Moreover, by isolating the stator structure, the stator becomes an integral body, and then more possible cooling methods can be provided for the stator, such as circulating oil injection cooling, etc., improving the power density of the device. By setting the combination of the motor rotor and the flywheel rotor, embedding the motor rotor magnets in the flywheel improves the structural compactness of the flywheel energy storage device and greatly improves its space utilization rate.
[0028] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0029] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A stator-isolated fully magnetically levitated flywheel energy storage device, comprising an isolated stator (1), characterized in that: The flywheel rotor (2) is suspended inside the isolated stator (1). Radial magnetic levitation mechanism (4) is fixedly connected to both the upper and lower ends of the isolated stator (1). An axial magnetic levitation mechanism (3) is fixedly connected to the opposite side of the two radial magnetic levitation mechanisms (4). A protective bearing (5) is fixedly connected inside the magnetic levitation mechanism (4).
2. The stator-isolated, fully magnetically levitated flywheel energy storage device according to claim 1, characterized in that: The isolation stator (1) includes a motor housing (101), an iron core (102), a stator armature winding (103), and an isolation cover (104). The isolation cover (104) is fixedly connected inside the motor housing (101). The iron core (102) is fixedly connected between the motor housing (101) and the isolation cover (104). The iron core (102) has stator slots, and the stator armature winding (103) is wound in the stator slots.
3. The stator-isolated, fully magnetically levitated flywheel energy storage device according to claim 2, characterized in that: The radial magnetic levitation mechanism (4) includes an upper radial magnetic levitation bearing (401), a housing (402), a lower radial magnetic levitation bearing (403), and a base (404). The housing (402) and the base (404) are respectively fixedly connected to the top and bottom of the motor housing (101). The upper radial magnetic levitation bearing (401) is fixedly connected inside the housing (402), and the lower radial magnetic levitation bearing (403) is fixedly connected inside the base (404). Both the upper radial magnetic levitation bearing (401) and the lower radial magnetic levitation bearing (403) are U-shaped ferromagnetic rings, and both the upper radial magnetic levitation bearing (401) and the lower radial magnetic levitation bearing (403) are equipped with excitation windings.
4. The stator-isolated, fully magnetically levitated flywheel energy storage device according to claim 2, characterized in that: The axial magnetic levitation mechanism (3) includes an upper axial magnetic levitation bearing (301) and a lower axial magnetic levitation bearing (302), which are arranged opposite to each other on the inner top wall and inner bottom wall of the motor housing (101).
5. A stator-isolated, fully magnetically levitated flywheel energy storage device according to claim 3, characterized in that: The flywheel rotor (2) includes a flywheel (201), a permanent magnet (202), a magnetic shielding ring (203), a carbon fiber sheath (204), an upper shaft (205), and a lower shaft (206). The top and bottom of the flywheel (201) are fixedly connected to the upper shaft (205) and the lower shaft (206) respectively. An annular groove is provided on the outside of the flywheel (201). The permanent magnet (202) is placed in the annular groove. Magnetic shielding rings (203) are placed at both the upper and lower ends of the permanent magnet (202). The permanent magnet (202) and the magnetic shielding rings (203) are covered with a carbon fiber sheath (204).
6. The stator-isolated, fully magnetically levitated flywheel energy storage device according to claim 3, characterized in that: Both the housing (402) and the base (404) are fixedly connected with protective bearings (5), which are used to support the rotation of the flywheel rotor (2) when the magnetic levitation mechanism fails.
7. A stator-isolated, fully magnetically levitated flywheel energy storage device according to claim 5, characterized in that: The upper radial magnetic levitation bearing (401) and the lower radial magnetic levitation bearing (403) are respectively fitted with an upper rotating shaft (205) and a lower rotating shaft (206). There is a first air gap between the upper radial magnetic levitation bearing (401) and the upper rotating shaft (205), and there is a second air gap between the lower radial magnetic levitation bearing (403) and the lower rotating shaft (206).
8. A stator-isolated, fully magnetically levitated flywheel energy storage device according to claim 2, characterized in that: The isolation cover (104) is a non-magnetic sealing barrel with a "Z" shaped cross-section and screw holes on the upper and lower end faces for fixing and sealing.