Magnetic-gathering stator permanent magnet type high-speed flywheel motor

Abstract

The invention discloses a magnetism-gathering stator permanent magnet type high-speed flywheel motor, and belongs to the technical field of high-speed motors. In order to solve the problems that an existing high-speed motor is poor in rotor strength, large in operation loss and low in power density, the high-speed motor comprises an outer rotor and an inner stator, and the inner stator comprises a main permanent magnet, an auxiliary permanent magnet, a stator iron core and an armature winding; the stator core is provided with main armature teeth and auxiliary armature teeth, the pair of main permanent magnets are arranged on one main armature tooth, and the outer edges of the main armature teeth are parallel to the main permanent magnets; the auxiliary armature teeth are protruding parts on the two sides of the main armature teeth, and the auxiliary permanent magnets are embedded into lateral steps formed by the main armature teeth and the auxiliary armature teeth. The auxiliary permanent magnets are distributed on the two sides of the main permanent magnet. The armature winding is wound on the main armature teeth; the main permanent magnets are magnetized in a parallel magnetizing mode with opposite magnetizing directions, and a V-shaped magnetism gathering type magnetic circuit is formed. The auxiliary permanent magnets are magnetized in a parallel magnetizing mode with opposite magnetizing directions. The invention is used for the flywheel system.

Description

Technical Field

[0001] The invention relates to a magnetic-concentrating stator permanent-magnet high-speed flywheel motor, belonging to the technical field of high-speed motors. Background Art

[0002] Energy storage technology is very important for building a safe, efficient and sustainable energy network, and is the key to meeting energy challenges and achieving energy security. Flywheel energy storage system plays a prominent role in modern power systems and new energy fields due to its advantages such as high power density, long cycle life, high environmental performance and low operating cost.

[0003] As the core of flywheel system energy conversion, the performance of high-speed motor directly affects the operation of the entire system. For example:

[0004] First, the high-speed rotor rotation generates a high-frequency magnetic field, which produces high-frequency losses in the iron core, windings, and permanent magnets. The limitations of the vacuum environment make heat dissipation extremely difficult, resulting in a temperature rise in the motor rotor. Excessive temperature rise will cause demagnetization and exceed the insulation level range.

[0005] Second, when the high-speed motor is running at rated conditions, the strong centrifugal force may cause the permanent magnet to fall off and break. At the same time, the system may resonate under the influence of the critical speed, which may cause damage to the system.

[0006] In summary, there are many key technical problems in the current high-speed flywheel motor system, which limits its engineering application. Summary of the invention

[0007] The purpose of the present invention is to solve the problems of poor rotor strength, large operating loss and low power density in existing high-speed motors, and to provide a magnetic-concentrating stator permanent magnet high-speed flywheel motor.

[0008] The present invention discloses a high-speed flywheel motor with a concentrated magnetic stator and a permanent magnet, which comprises an outer rotor and an inner stator, wherein the inner stator comprises a main permanent magnet, an auxiliary permanent magnet, a stator core and an armature winding;

[0009] The stator core is provided with main armature teeth and auxiliary armature teeth, a pair of main permanent magnets are placed on one main armature tooth, and the outer edge of the main armature tooth is parallel to the main permanent magnet; the auxiliary armature teeth are protruding parts on both sides of the main armature teeth, and the auxiliary permanent magnets are embedded in the side steps formed by the main armature teeth and the auxiliary armature teeth; the auxiliary permanent magnets are distributed on both sides of the main permanent magnets; the armature winding is wound on the main armature teeth;

[0010] The main permanent magnet is magnetized by a parallel magnetization method with opposite magnetization directions to form a "V"-shaped magnetic field concentrating magnetic circuit; the auxiliary permanent magnet is magnetized by a parallel magnetization method with opposite magnetization directions.

[0011] Preferably, it also includes a rotating flywheel, which is arranged on the outside of the outer rotor and fits with the iron core of the outer rotor to form a rotor structure together.

[0012] Preferably, the armature winding adopts concentrated winding.

[0013] Preferably, the outer rotor has 16 poles and the inner stator has 6 slots, forming a pole-slot matching mode.

[0014] Preferably, the outer rotor includes 16 rotor teeth, adopts a salient pole structure, and there is an angle difference between the raised part and the recessed part, and they are evenly distributed.

[0015] Preferably, the number of the main armature teeth is 6, the number of the auxiliary armature teeth is 12, the number of the main permanent magnets is 6 pairs, the number of the auxiliary permanent magnets is 6 pairs, and the number of the armature windings is 12;

[0016] The 6 pairs of main permanent magnets are V-shaped and built into the 6 main armature teeth respectively, and the 6 pairs of auxiliary permanent magnets are embedded in the 12 auxiliary armature teeth respectively; the 12 armature windings are wound on the 6 main armature teeth respectively, forming a double-layer three-phase distributed concentrated winding in the 6 slots.

[0017] Preferably, a pair of main permanent magnets built into the same main armature tooth are magnetized by a parallel magnetization method of relative magnetization, and the magnetization angle is perpendicular to the main permanent magnets;

[0018] The auxiliary permanent magnets on both sides of the same main armature tooth are magnetized along the length direction of the main permanent magnet, and the magnetization directions of the auxiliary permanent magnets on both sides of the same main armature tooth are opposite.

[0019] Preferably, the armature winding includes an A-phase positive coil, an A-phase negative coil, a B-phase positive coil, a B-phase negative coil, a C-phase positive coil and a C-phase negative coil;

[0020] The windings on the opposite side are mirror-symmetrical;

[0021] The A-phase positive coil and the A-phase negative coil are connected in series in a forward direction to form the A-phase armature winding;

[0022] The B-phase positive coil and the B-phase negative coil are connected in series in a forward direction to form a B-phase armature winding;

[0023] The C-phase positive coil and the C-phase negative coil are connected in series in a forward direction to form a C-phase armature winding;

[0024] The spatial positions of the three-phase armature windings differ by 120 degrees.

[0025] Preferably, the stator core is made of super silicon steel sheet with a thickness of 0.1 mm or 0.15 mm.

[0026] Preferably, the main permanent magnet and the auxiliary permanent magnet are segmented in the axial direction;

[0027] The main permanent magnet and the auxiliary permanent magnet are both made of neodymium iron boron.

[0028] Advantages of the invention: The invention proposes a new topology structure of a high-speed flywheel motor with high rotor strength, low operating loss and high power density, which improves the power density of the high-speed flywheel motor and solves the technical problems of excessive rotor strength and temperature rise in a vacuum environment. It has the following advantages:

[0029] 1. The rotor structure is simple and the rotor strength is high. No sleeve is needed to ensure the rotor strength, which shortens the air gap length and improves the output torque and power density.

[0030] 2. The stator core is composed of main armature teeth and auxiliary armature teeth. The winding is wound between the main armature teeth. On the one hand, the auxiliary armature teeth can effectively increase the convenience of winding and prevent the winding from coming out. On the other hand, the auxiliary armature teeth provide auxiliary magnetic flux circuits, reduce the opening width of the winding slots, increase the equivalent air gap length, reduce torque pulsation, and increase output power.

[0031] 3. The main permanent magnet and the auxiliary permanent magnet work together. The main permanent magnet is a pair of parallel magnetized permanent magnets with relative magnetization. There is an angle between the main permanent magnets, which is V-shaped. The relative magnetization forms a magnetic field concentration effect to improve the power density. The auxiliary permanent magnet is a pair of parallel magnetized permanent magnets with opposite magnetization directions. It can improve the waveform of the main magnetic field, reduce the air gap magnetic flux distortion rate, reduce eddy current loss, reduce torque pulsation, and suppress motor heat generation; at the same time, it increases the magnetic field amplitude, increases the magnetic field concentration effect, and improves the motor power density.

[0032] 4. The pole-slot matching method of 6 slots and 16 poles is adopted, which is different from the traditional I-type permanent magnet. The winding area is increased and higher torque is provided under the same current density. The windings are complementary under this pole-slot matching. The complementary coils eliminate the asymmetric flux and back electromotive force caused by a single coil, effectively reducing the positioning torque and the torque pulsation of the motor.

[0033] 5. The stator adopts a permanent magnet structure, and the rotor is only a silicon steel sheet. It has a single structure and a single material. There are no permanent magnets or windings, which improves the rotor strength and suppresses the loss, making it suitable for high-speed operation.

[0034] 6. The stator and rotor cores are made of ultra-thin super silicon steel sheets, which effectively suppress the generation of motor core loss, suppress the motor temperature rise, and improve system efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a structural schematic diagram of a magnetic-concentrating stator permanent magnet type high-speed flywheel motor according to the present invention;

[0036] Figure 2It is an axial view of a magnetic-concentrating stator permanent magnet type high-speed flywheel motor according to the present invention;

[0037] Figure 3 It is a schematic diagram of the magnetization direction of the main permanent magnet and the auxiliary permanent magnet of the present invention;

[0038] Figure 4 It is a magnetic flux line trend diagram of the main permanent magnet of the present invention;

[0039] Figure 5 It is a magnetic flux line trend diagram of the auxiliary permanent magnet of the present invention;

[0040] Figure 6 It is a schematic diagram of the distribution of magnetic lines of force under the action of the main permanent magnet alone according to the present invention;

[0041] Figure 7 is a schematic diagram of the distribution of magnetic lines of force under the action of the auxiliary permanent magnet alone according to the present invention;

[0042] Figure 8 This is a schematic diagram of the magnetic field line distribution of the stator and rotor during no-load operation;

[0043] Fig. 9 This is a structural diagram of a 16-pole, 6-slot, magnetic-concentrating stator permanent magnet high-speed flywheel motor. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0046] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0047] Embodiment 1:

[0048] Combine the following Figure 1-Figure 9 The present embodiment is described as a high-speed flywheel motor with a concentrated magnetic stator and a permanent magnet, which comprises an outer rotor 1 and an inner stator 2, wherein the inner stator 2 comprises a main permanent magnet 3, an auxiliary permanent magnet 4, a stator core 5 and an armature winding 6;

[0049] The stator core 5 is provided with a main armature tooth 7 and an auxiliary armature tooth 8. A pair of main permanent magnets 3 are built into one of the main armature teeth 7. The outer edge of the main armature tooth 7 is parallel to the main permanent magnet 3. The auxiliary armature teeth 8 are protruding parts on both sides of the main armature teeth 7. The auxiliary permanent magnets 4 are embedded in the side steps formed by the main armature teeth 7 and the auxiliary armature teeth 8. The auxiliary permanent magnets 4 are distributed on both sides of the main permanent magnets 3. The armature winding 6 is wound on the main armature teeth 7.

[0050] The main permanent magnet 3 is magnetized by parallel magnetization with opposite magnetization directions to form a "V"-shaped magnetic field circuit; the auxiliary permanent magnet 4 is magnetized by parallel magnetization with opposite magnetization directions.

[0051] Further, such as Fig. 9 As shown, it also includes a rotating flywheel 9, which is arranged on the outside of the outer rotor 1 and fits with the iron core of the outer rotor 1 to form a rotor structure.

[0052] Furthermore, the armature winding 6 adopts concentrated winding.

[0053] Furthermore, the outer rotor 1 has 16 poles and the inner stator 2 has 6 slots, forming a pole-slot matching mode.

[0054] Furthermore, the outer rotor 1 includes 16 rotor teeth, adopts a salient pole structure, and there is an angle difference between the raised part and the recessed part, and they are evenly distributed.

[0055] Furthermore, the number of the main armature teeth 7 is 6, the number of the auxiliary armature teeth 8 is 12, the number of the main permanent magnets 3 is 6 pairs, the number of the auxiliary permanent magnets 4 is 6 pairs, and the number of the armature windings 6 is 12;

[0056] The six pairs of main permanent magnets 3 are V-shaped and built into the six main armature teeth 7, and the six pairs of auxiliary permanent magnets 4 are embedded in the twelve auxiliary armature teeth 8; the twelve armature windings 6 are wound around the six main armature teeth 7, forming a double-layer three-phase distributed concentrated winding in the six slots.

[0057] Furthermore, a pair of main permanent magnets 3 built into the same main armature tooth 7 are magnetized by a parallel magnetization method of relative magnetization, and the magnetization angle is perpendicular to the main permanent magnets 3;

[0058] The auxiliary permanent magnets 4 on both sides of the same main armature tooth 7 are magnetized along the length direction of the main permanent magnet 3 , and the magnetization directions of the auxiliary permanent magnets 4 on both sides of the same main armature tooth 7 are opposite.

[0059] Furthermore, the armature winding 6 includes an A-phase positive coil 61, an A-phase negative coil 62, a B-phase positive coil 63, a B-phase negative coil 64, a C-phase positive coil 65 and a C-phase negative coil 66;

[0060] The windings on the opposite side are mirror-symmetrical;

[0061] The A-phase positive coil 61 and the A-phase negative coil 62 are connected in series in a forward direction to form an A-phase armature winding;

[0062] The B-phase positive coil 63 and the B-phase negative coil 64 are connected in series in a forward direction to form a B-phase armature winding;

[0063] The C-phase positive coil 65 and the C-phase negative coil 66 are connected in series in a forward direction to form a C-phase armature winding;

[0064] The spatial positions of the three-phase armature windings differ by 120 degrees.

[0065] Furthermore, the stator core 5 is made of super silicon steel sheet with a thickness of 0.1 mm or 0.15 mm.

[0066] In this embodiment, a stator permanent magnet structure is adopted, and the rotor is only a silicon steel sheet, which is a single structure and a single material. There is no permanent magnet or winding, which improves the rotor strength and suppresses the loss generation, and is suitable for high-speed operation. The stator core 5 is made of ultra-thin super silicon steel sheets, which effectively suppresses the generation of motor core loss, suppresses the motor temperature rise, and improves system efficiency.

[0067] Furthermore, the main permanent magnet 3 and the auxiliary permanent magnet 4 are segmented in the axial direction;

[0068] The main permanent magnet 3 and the auxiliary permanent magnet 4 are both made of neodymium iron boron.

[0069] In this embodiment, eddy current loss is reduced by axial segmentation.

[0070] In the present invention, the motor includes an outer rotor 1 and an inner stator 2, and the stator is composed of a main permanent magnet 3, an auxiliary permanent magnet 4, a stator core 5, and an armature winding 6. The stator core 5 is provided with a main armature tooth 7 and an auxiliary armature tooth 8, the main armature tooth 7 has a pair of main permanent magnets 3 built in it, and the auxiliary armature teeth 8 are embedded with a pair of auxiliary permanent magnets 4. The main permanent magnet 3 adopts parallel magnetization with relative magnetization to form a V-shaped magnetization type, and the auxiliary permanent magnet 4 adopts parallel magnetization with opposite magnetization directions. The armature winding 6 adopts concentrated winding and is wound on the main armature teeth 7.

[0071] In the present invention, Fig. 9 As shown, it is a 16-pole 6-slot magnetic stator permanent magnet high-speed flywheel motor. Figure 1 and Fig. 9As shown, in the outer rotor 1 of the motor of the present invention, there are 16 rotor teeth, which adopt a salient pole structure, and there is an angle difference between the raised part and the recessed part, and they are evenly distributed. There are 6 main armature teeth 7 and 12 auxiliary armature teeth 8 in the stator 2. 6 pairs of main permanent magnets 3 are built into the main armature teeth 7 in a V shape, and 6 pairs of auxiliary permanent magnets 4 are embedded in the auxiliary armature teeth 8, and the auxiliary permanent magnets 4 are distributed on both sides of the main permanent magnets 3. 12 armature windings 6 are wound around the main armature teeth 7, forming a double-layer three-phase distributed concentrated winding in 6 slots. On the outside of the motor is a rotating flywheel 9, which is in contact with the outer rotor core 1 to form a rotor structure together.

[0072] like Figure 2 As shown, the stator 2 has 12 armature windings 6, which are A-phase positive coil 61, A-phase negative coil 62, B-phase positive coil 63, B-phase negative coil 64, C-phase positive coil 65, C-phase negative coil 66, and the opposite windings are mirror-symmetrical. When the mirror-symmetrical windings are connected in series in the forward direction, the magnetic flux is complementary to form the A-phase armature winding to offset a large number of harmonics. The coils of the B-phase and C-phase are arranged in the same way, and the spatial positions of the three-phase armature windings differ by 120 degrees.

[0073] like Figure 3 As shown, 12 main permanent magnets 3 and 12 auxiliary permanent magnets 4 are respectively placed on the stator core 2, and the main permanent magnets 3 built into the same main armature tooth 7 are magnetized in parallel with each other, and the magnetization angle is perpendicular to the main permanent magnets 3. On both sides of the same main armature tooth 7, the auxiliary armature teeth 8 are embedded with the auxiliary permanent magnets 4, and the magnetization direction of the auxiliary permanent magnets 4 is along the length direction of the main permanent magnets, and the directions on both sides are opposite.

[0074] like Figure 4 and Figure 5 As shown, the operating principle of the motor of the present invention is explained: when the rotor salient poles are respectively relative to the main permanent magnet 3 and the adjacent stator core 2, the magnetic flux direction inside the middle coil is downward; when the rotor salient poles are respectively relative to the stator core 2 and the adjacent main permanent magnet 3, the magnetic flux direction inside the middle coil is upward; when the rotor salient poles are respectively relative to the auxiliary permanent magnet 4, the magnetic flux inside the left coil is formed by rotor 1-left auxiliary permanent magnet 4-left auxiliary armature tooth 8-stator core 2-right auxiliary armature tooth 8-right auxiliary permanent magnet 4-rotor 1, forming a closed magnetic flux, and the direction is clockwise; when the rotor salient poles are respectively relative to the auxiliary permanent magnet 4, the magnetic flux inside the left coil is formed by rotor 1-right auxiliary permanent magnet 4-right auxiliary armature tooth 8-stator core 2-left auxiliary armature tooth 8-left auxiliary permanent magnet 4-rotor 1, forming a closed magnetic flux, and the direction is counterclockwise.

[0075] The present invention uses the main permanent magnet 3 and the auxiliary permanent magnet 4 in combination, and the magnetic fluxes are superimposed to increase the air gap magnetic density, thereby increasing the air gap magnetic field, and the auxiliary magnetic field can optimize the main magnetic field.

[0076] like Figure 6 , Figure 7 and Figure 8 As shown, the magnetic lines of force of the present invention follow the principle of minimum magnetic resistance. When the main permanent magnet 3 acts alone, the magnetic lines of force are more; when the auxiliary permanent magnet 4 acts alone, the magnetic lines of force are sparse; when the permanent magnets act together, the magnetic lines of force are more abundant, indicating that there is a magnetic concentration effect.

[0077] The high-speed motor of the present invention can operate in a motor mode or a generator mode.

[0078] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be used in other described embodiments.

Claims

1. A magnetic concentrating stator permanent magnet type high-speed flywheel motor, comprising an outer rotor (1) and an inner stator (2), wherein the inner stator (2) comprises a main permanent magnet (3), an auxiliary permanent magnet (4), a stator core (5) and an armature winding (6); It is characterized in that The stator core (5) is provided with a main armature tooth (7) and an auxiliary armature tooth (8); a pair of main permanent magnets (3) are built into one of the main armature teeth (7); the outer edge of the main armature tooth (7) is parallel to the main permanent magnet (3); the auxiliary armature teeth (8) are protruding parts on both sides of the main armature teeth (7); the auxiliary permanent magnets (4) are embedded in the side steps formed by the main armature teeth (7) and the auxiliary armature teeth (8); the auxiliary permanent magnets (4) are distributed on both sides of the main permanent magnet (3); and the armature winding (6) is wound on the main armature teeth (7); The main permanent magnet (3) is magnetized by a parallel magnetization method with opposite magnetization directions, forming a "V"-shaped magnetic field concentrating magnetic circuit; the auxiliary permanent magnet (4) is magnetized by a parallel magnetization method with opposite magnetization directions.

2. A magnetic concentrating stator permanent magnet high-speed flywheel motor according to claim 1, It is characterized in that It also includes a rotating flywheel (9), which is arranged on the outside of the outer rotor (1) and fits with the iron core of the outer rotor (1) to form a rotor structure.

3. A magnetic concentrating stator permanent magnet high-speed flywheel motor according to claim 1, It is characterized in that The armature winding (6) adopts concentrated winding.

4. A magnetic concentrating stator permanent magnet high-speed flywheel motor according to claim 1, It is characterized in that The outer rotor (1) has 16 poles and the inner stator (2) has 6 slots, forming a pole-slot matching mode.

5. A magnetic concentrating stator permanent magnet high-speed flywheel motor according to claim 4, It is characterized in that The outer rotor (1) comprises 16 rotor teeth and adopts a salient pole structure; there is an angle difference between the convex part and the concave part, and the teeth are evenly distributed.

6. A magnetic concentrating stator permanent magnet high-speed flywheel motor according to claim 4 or 5, It is characterized in that The number of the main armature teeth (7) is 6, the number of the auxiliary armature teeth (8) is 12, the number of the main permanent magnets (3) is 6 pairs, the number of the auxiliary permanent magnets (4) is 6 pairs, and the number of the armature windings (6) is 12; Six pairs of main permanent magnets (3) are respectively built into six main armature teeth (7) in a "V" shape, and six pairs of auxiliary permanent magnets (4) are respectively embedded in 12 auxiliary armature teeth (8); and 12 armature windings (6) are respectively wound on the six main armature teeth (7), forming a double-layer three-phase distributed concentrated winding in the six slots.

7. A magnetic concentrating stator permanent magnet high-speed flywheel motor according to claim 6, It is characterized in that A pair of main permanent magnets (3) built into the same main armature tooth (7) are magnetized by a parallel magnetization method of relative magnetization, and the magnetization angle is perpendicular to the main permanent magnets (3); The auxiliary permanent magnets (4) on both sides of the same main armature tooth (7) are magnetized along the length direction of the main permanent magnet (3), and the magnetization directions of the auxiliary permanent magnets (4) on both sides of the same main armature tooth (7) are opposite.

8. The high-speed flywheel motor with a concentrated magnetic stator and permanent magnet according to claim 6, It is characterized in that The armature winding (6) comprises an A-phase positive coil (61), an A-phase negative coil (62), a B-phase positive coil (63), a B-phase negative coil (64), a C-phase positive coil (65) and a C-phase negative coil (66); The windings on the opposite side are mirror-symmetrical; The A-phase positive coil (61) and the A-phase negative coil (62) are connected in series in a forward direction to form an A-phase armature winding; A B-phase positive coil (63) and a B-phase negative coil (64) are connected in series in a forward direction to form a B-phase armature winding; The C-phase positive coil (65) and the C-phase negative coil (66) are connected in series in a forward direction to form a C-phase armature winding; The spatial positions of the three-phase armature windings differ by 120 degrees.

9. The high-speed flywheel motor with a concentrated magnetic stator and permanent magnet according to claim 1, It is characterized in that The stator core (5) is made of super silicon steel sheet with a thickness of 0.1 mm or 0.15 mm.

10. The high-speed flywheel motor with a concentrated magnetic stator and permanent magnet according to claim 1, It is characterized in that The main permanent magnet (3) and the auxiliary permanent magnet (4) are segmented in the axial direction; The main permanent magnet (3) and the auxiliary permanent magnet (4) are both made of neodymium iron boron.

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