Rotor punching sheet of high-efficiency permanent magnet synchronous motor

Abstract

The invention provides a rotor punching sheet of a high-efficiency permanent magnet synchronous motor, and relates to the technical field of permanent magnet synchronous motors. The rotor punching sheet provided by the invention is designed according to the following steps: according to symmetry, one pole of the motor rotor punching sheet is designed to be a sector, the unfolding angle of the sector is 180 / p degrees, and p is the number of pole pairs; the center axis of the sector, the boundary straight line and the inner arc line of the motor stator are taken as the reference, the boundary position of the hole is drawn by adopting a geometric construction method, the formed hole is used for inserting the permanent magnet with the rectangular section, and the permanent magnets in the hole have the same specification. According to the invention, serialized high-efficiency permanent magnet rotor punching sheets can be rapidly designed, and the motor cost is reduced; the outer side area of the pole part is small, so that the stress of the rotor reinforcing rib is small; the linear permanent magnets are small in width, so that the flux density of the stator is reduced, and the iron loss of the stator is reduced; the permanent magnets with rectangular cross sections can be inserted into the rotor iron core formed by laminating the punching sheets, so that the manufacturing and mounting cost of the permanent magnets is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of permanent magnet synchronous motors, and in particular to a rotor punching sheet of a high-efficiency permanent magnet synchronous motor. Background Art

[0002] Variable frequency speed regulation permanent magnet synchronous motor has the advantage of high efficiency, but if the amount of permanent magnet used is too large, it will lead to excessive excitation, making the stator magnetic flux density too large and causing the stator iron loss to increase, making it impossible for the motor to achieve higher efficiency by increasing the armature diameter and length.

[0003] The variable frequency speed regulation permanent magnet synchronous motor rotor adopts a permanent magnet insertion structure, which reduces the difficulty of permanent magnet rotor manufacturing and facilitates automated mass production. However, the pole area of ​​traditional V-type, double V-type, inverted A-type and other permanent magnet insertion topological structures is too large, resulting in excessive centrifugal stress in the magnetic bridge part. The large amount of rotor permanent magnets leads to large iron loss in the stator, thereby reducing the motor efficiency.

[0004] Invention patent CN112653274 B "Rotor punching and permanent magnet motor rotor" adopts a double V structure, and the area of ​​the silicon steel part outside the permanent magnet is too large, resulting in excessive centrifugal stress in the magnetic bridge part. CN109742879B "A permanent magnet motor rotor structure" adopts multiple arc parts or multiple arc parts and multiple line segments connected in a symmetrical manner along the circumferential direction of the rotor core, forming an uneven air gap. Although it reduces the stray loss of the permanent magnet motor, it increases the air gap and thus reduces the torque.

[0005] Therefore, in order to further improve the efficiency of permanent magnet motors, it is necessary to provide a rotor punching suitable for high-efficiency permanent magnet synchronous motors. The equal air gap, straight-line rotor permanent magnet topology structure designed by the present invention reduces the pole area, rotor magnetic bridge stress, stator iron loss, no-load cogging torque and load torque fluctuation, and realizes the rotor punching design of serialized high-efficiency permanent magnet motors. Summary of the invention

[0006] The purpose of the present invention is to provide a rotor punching of a high-efficiency permanent magnet synchronous motor in view of the above-mentioned deficiencies in the prior art, so as to solve the problem of rapid serial design and optimization of the rotor punching of the high-efficiency permanent magnet synchronous motor.

[0007] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0008] The present invention provides a rotor punching sheet of a high-efficiency permanent magnet synchronous motor, and the rotor punching sheet is designed by the following steps:

[0009] S1: According to symmetry, one pole of the motor rotor punching sheet is designed as a sector, the expansion angle of the sector is 180 / p degrees, p is the number of pole pairs, and the rotor structure under one pole is symmetrical about the central axis X of the sector, the left boundary straight line of the sector is Y, the part of the inner circle of the motor stator corresponding to the one pole is arc L1, the center of the circle is the center of the motor shaft O, the radius of the arc L1 is R1, the arc L1 is offset toward the center of the circle by the air gap length g1 to obtain the outer circle boundary arc L2 of the motor rotor, the radius of L2 is R2, R2 = R1-g1;

[0010] S2: The arc L2 is offset toward the center by a distance g2 to obtain the arc L3, whose radius is R3, R3 = R2-g2;

[0011] S3: The central axis X rotates around O toward the boundary line Y by an angle a1 / 2 to obtain a straight line OA, which intersects L3 at point A.

[0012] S4: Draw a straight line L4 through point A, perpendicular to the center axis X, and the distance from point A to the center axis is b1; L4 is offset toward the center of the circle by a distance h1 to obtain a straight line L5, which intersects the center axis at point K;

[0013] Go to S5.1 or S6.1 or S7.1;

[0014] S5.1: The center axis X is offset toward the boundary line Y by a distance g3 / 2 to obtain line segment JH, which intersects L4 at point H and intersects L5 at point J;

[0015] S5.2: Line JH is offset by a distance b2 in the Y direction of the boundary line to obtain line segment DE, which intersects L5 at point D. The length of DJ is b2, the length of DE is g4, and the direction from point D to point E points to the side of line L4;

[0016] S5.3: Draw a line segment EF through point E that is perpendicular to DE. The length of EF is g5. The direction from point E to point F points to the side of boundary line Y. Draw a line segment FG through point F that is perpendicular to EF. The length of FG is g4. The direction from point F to point G points to the side of the center of the circle.

[0017] S5.4: The boundary line Y is rotated about the center O in the direction of the central axis X by an angle a2 to obtain the line OB. The line OB intersects L3 and point B. A line BC is drawn through point B and parallel to the boundary line Y. A line perpendicular to BC is drawn through point G, and the foot of the perpendicular is point C.

[0018] S5.5: The polygon BCGFEDJHA forms a hole, which is mirrored about the central axis to form two holes for inserting permanent magnets with rectangular cross-sections. The permanent magnets in the holes have the same specifications, and the corners of each hole are rounded;

[0019] Go to step S8;

[0020] S6.1: The central axis X intersects the straight line L4 and the straight line L5 at points M and K;

[0021] S6.2: The center axis X is offset toward the boundary line Y by a distance b3 / 2 to obtain line segment QR, which intersects L4 at point R and intersects L5 at point Q;

[0022] S6.3: QR is offset by a distance g3 in the Y direction of the boundary line to obtain a line segment PN, which intersects L4 at point N and intersects L5 at point P;

[0023] S6.4: PN is offset by a distance b3 in the Y direction of the boundary line to obtain line segment DE, which intersects L5 at point D. The length of DJ is b2, the length of DE is g4, and the direction from point D to point E points to the side of line L4;

[0024] S6.5: Draw a line segment EF through point E that is perpendicular to DE. The length of EF is g5. The direction from point E to point F points to the side of boundary line Y. Draw a line segment FG through point F that is perpendicular to EF. The length of FG is g4. The direction from point F to point G points to the side of the center of the circle.

[0025] S6.6: The boundary line Y is rotated about the center O in the direction of the central axis X by an angle a2 to obtain the line OB. The line OB intersects L3 and point B. A line BC is drawn through point B and parallel to the boundary line Y. A line perpendicular to BC is drawn through point G, and the foot of the perpendicular is point C.

[0026] S6.7: The polygon BCGFEDPNA forms one hole, and the quadrilateral RQKM forms another hole. The above two holes are mirrored about the central axis to form three holes for inserting permanent magnets with rectangular cross-sections. The permanent magnets in the holes have the same specifications, and the sharp corners of each hole are rounded;

[0027] Go to step S8;

[0028] S7.1: The central axis X intersects the straight line L4 and the straight line L5 at points M and K;

[0029] S7.2: Line KM is offset in the Y direction of the boundary line by a distance g3 / 2 to obtain line segment JH, which intersects L4 at point H and intersects L5 at point J;

[0030] S7.3: Line JH is offset by a distance b4 in the Y direction of the boundary line to obtain line segment QR, which intersects L4 at point R and intersects L5 at point Q;

[0031] S7.4: Line QR is offset by a distance g3 in the Y direction of the boundary line to obtain line segment PN, which intersects L4 at point N and intersects L5 at point P;

[0032] S7.5: PN is offset by a distance b4 in the Y direction of the boundary line to obtain line segment DE, which intersects L5 at point D. The length of DJ is b2, the length of DE is g4, and the direction from point D to point E points to the side of line L4;

[0033] S7.6: Draw a line segment EF through point E that is perpendicular to DE. The length of EF is g5. The direction from point E to point F points to the side of boundary line Y. Draw a line segment FG through point F that is perpendicular to EF. The length of FG is g4. The direction from point F to point G points to the side of the center of the circle.

[0034] S7.7: The boundary line Y is rotated about the center O in the direction of the central axis X by an angle a2 to obtain the line OB. The line OB intersects L3 and point B. A line BC is drawn through point B and parallel to the boundary line Y. A line perpendicular to BC is drawn through point G, with the foot of the perpendicular being point C.

[0035] S7.8: The polygon BCGFEDPNA forms one hole, and the quadrilateral RQJH forms another hole. The above two holes are mirrored about the central axis to form four holes for inserting permanent magnets with rectangular cross-sections. The permanent magnets in the holes have the same specifications, and the sharp corners of each hole are rounded;

[0036] S8: The hole structure under other residual poles is replicated through a circular array.

[0037] Optionally, the straight line L5 is offset by a distance h2 toward the center of the circle to obtain a straight line L6; the inner arc line L8 of the rotor is offset by a distance h3 away from the center of the circle to obtain an arc line L7; a straight line L9 is drawn through point K, and the angle between L9 and the central axis X is a3, and a3 is 40 degrees to 50 degrees; the boundary straight line Y is offset by a distance h4 toward the central axis X to obtain a straight line L 10 The above straight line L6, arc L7, straight line L9, straight line L 10 and the center axis X, the hole is mirrored about the center axis X to form a large hole, where the fillet r1 between L6 and L9, L 10 and L9, r2, L7 and L 10 The corners r3 are rounded between them, and the above-mentioned hole structure under other residual poles is replicated through a circular array; the value range of h2 is: 0.15×R1 / p to 0.4×R1 / p, the value range of h3 is: 0.15×R1 / p to 0.5×R1 / p, the value range of h4 is: 0.05×R1 / p to 0.5×R1 / p, the value range of r1 is: 0.04×R1 / p to 0.4×R1 / p, the value range of r2 is: 0.04×R1 / p to 0.2×R1 / p, and the value range of r3 is: 0.04×R1 / p to 0.2×R1 / p.

[0038] Optionally, in S1, the pole pair number p is one of the following: 2, 3, 4; in S1, the value range of the radius R1 is: 25 mm to 220 mm.

[0039] Optionally, in S2, the value range of g2 is: g1 to 2×g1; in S3, the value range of a1 is: 0.64×180 / p degrees to 0.8×180 / p degrees.

[0040] Optionally, in S4, the value range of h1 is: 3×g1 to 5×g1; in S5.1, S6.3 and S7.2, the value range of g3 is: 0 or 0.5 mm to 2 mm.

[0041] Optionally, in S5.2, the value range of b2 is: 0.85×b1 to 0.91×b1; in S5.2, S6.4 and S7.5, the value range of g4 is: 0.4mm to 2mm; in S5.3, S6.5 and S7.6, the value range of g5 is: 0.7mm to 2mm.

[0042] Optionally, in S5.4, S6.6 and S7.7, the value range of a2 is: 0.024×180 / p degrees to 0.026×180 / p degrees.

[0043] Optionally, in S6.2, the value range of b3 is: 0.56×b1 to 0.61×b1; in S7.3, the value range of b4 is: 0.42×b1 to 0.46×b1.

[0044] Optionally, the cavity where the permanent magnet slot is located is filled with insulating material to reduce the maximum stress of the rotor.

[0045] The beneficial effects of the present invention include:

[0046] The rotor punching provided by the present invention is designed according to the following steps: according to symmetry, one pole of the motor rotor punching is designed as a sector, the expansion angle of the sector is 180 / p degrees, and p is the number of pole pairs; the central axis of the sector, the boundary straight line and the inner arc line of the motor stator are used as references, and the boundary position of the hole is drawn by geometric drawing method, and the formed hole is used to insert the permanent magnet with a rectangular cross section, and the specifications of the permanent magnets in the hole are the same. The present invention can quickly design serialized high-efficiency permanent magnet rotor punchings, improve the level of standardization and serialization, and thus reduce the cost of the motor; because the outer area of ​​the pole part is small, the stress of the rotor reinforcement rib is small; the rotor can open a larger lightening hole to reduce the weight of the rotor; the width of the one-line permanent magnet is small, which reduces the stator magnetic density, thereby reducing the stator iron loss; the optimization of the magnetic bridge position can reduce the rotor no-load cogging torque and torque fluctuation under load; the rotor core of the punching stacked by the present invention can be inserted with a rectangular cross-section permanent magnet, reducing the manufacturing and installation costs of the permanent magnet. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0048] Figure 1A A schematic structural diagram of one pole of an 8-pole permanent magnet synchronous motor rotor punching sheet provided by an embodiment of the present invention is shown;

[0049] Figure 1B and Figure 1C Shows Figure 1A A partial enlarged view of

[0050] Figure 2A A schematic structural diagram of one pole of an 8-pole permanent magnet synchronous motor rotor punching sheet provided by an embodiment of the present invention is shown;

[0051] Figure 2B Shows Figure 2A A partial enlarged view of

[0052] Figure 3 A schematic structural diagram of one pole of another 8-pole permanent magnet synchronous motor rotor punching sheet provided by an embodiment of the present invention is shown;

[0053] Figure 4A A schematic structural diagram of one pole of another 8-pole permanent magnet synchronous motor rotor punching sheet provided by an embodiment of the present invention is shown;

[0054] Figure 4B Shows Figure 4A A partial enlarged view of

[0055] Figure 5 A schematic structural diagram of an 8-pole complete rotor punching inserted with permanent magnets provided by an embodiment of the present invention is shown.

[0056] Figure 6 A schematic structural diagram of a 6-pole complete rotor punching inserted with permanent magnets provided in an embodiment of the present invention is shown.

[0057] Figure 7 A schematic structural diagram of a 4-pole complete rotor punching sheet with permanent magnets inserted therein provided by an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0058] 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.

[0059] The variable frequency speed regulation permanent magnet synchronous motor rotor adopts a permanent magnet insertion structure, which reduces the difficulty of permanent magnet rotor manufacturing and facilitates automated mass production. However, the traditional V-type, double V-type, inverted A-type and other permanent magnet insertion topological structures have a large pole area, which leads to excessive centrifugal stress in the magnetic bridge part. The large amount of rotor permanent magnets leads to large iron loss in the stator, thereby reducing the motor efficiency. Therefore, in order to further improve the efficiency of the permanent magnet motor, it is necessary to provide a rotor punching suitable for high-efficiency permanent magnet synchronous motors, design equal air gap, one-line rotor permanent magnet topological structure, reduce the pole area, reduce rotor magnetic bridge stress, reduce stator iron loss, reduce no-load cogging torque, reduce load torque fluctuation, and realize the rotor punching design of serialized high-efficiency permanent magnet motors.

[0060] Figure 1A and Figure 2A A schematic structural diagram of one pole of a permanent magnet synchronous motor rotor punching sheet provided by an embodiment of the present invention is shown; Figure 1B to Figure 1C They are Figure 1A Enlarged view of parts I and II in the middle, Figure 2B yes Figure 2A The enlarged view of the middle part I, and the enlargement ratio is 4:1.

[0061] Figure 3 A schematic structural diagram of one pole of another permanent magnet synchronous motor rotor punching sheet provided by an embodiment of the present invention is shown.

[0062] Figure 4A A schematic structural diagram of one pole of a permanent magnet synchronous motor rotor punching sheet provided by an embodiment of the present invention is shown; Figure 4B yes Figure 4A An enlarged view of part I in the middle, with an enlargement ratio of 4:1.

[0063] Figure 5 A schematic structural diagram of a complete rotor punching sheet with permanent magnets inserted therein provided by an embodiment of the present invention is shown; Figure 6 A schematic structural diagram of a 6-pole complete rotor punching sheet with permanent magnets inserted therein provided by an embodiment of the present invention is shown; Figure 7 A schematic structural diagram of a 4-pole complete rotor punching sheet with permanent magnets inserted therein provided by an embodiment of the present invention is shown.

[0064] exist Figure 1A and Figure 2AIn each pole, there are two permanent magnet slots, in which two rectangular cross-section permanent magnets are placed; Figure 3 In each pole, there are three permanent magnet slots, and three rectangular cross-section permanent magnets are placed; Figure 4A In the example, each pole has 4 permanent magnet slots, which contain 4 rectangular cross-section permanent magnets. Figures 1A to 4A As shown in the figure, increasing the number of permanent magnet slots can reduce the centrifugal stress of the magnetic bridge without increasing the width of the magnetic bridge, reduce the width dimension of the permanent magnet, and avoid the permanent magnet being too flat. Figure 1A , Figure 3 , Figure 4A When the width g3 of the middle magnetic bridge is zero, the number of permanent magnet slots is reduced to one, and one rectangular cross-section permanent magnet is placed. Figure 5 In FIG. 5 , a permanent magnet 52 and a silicon steel sheet 51 are shown; Figure 6 In FIG. 6 , a permanent magnet 62 and a silicon steel sheet 61 are shown; in FIG. Figure 7 In FIG. 7 , a permanent magnet 72 and a silicon steel sheet 71 are shown.

[0065] The following will refer to Figures 1A to 7 The technical solution of the present invention is described in detail.

[0066] The present invention provides a rotor punching sheet of a high-efficiency permanent magnet synchronous motor, and the rotor punching sheet is designed by the following steps:

[0067] S1: According to symmetry, one pole of the motor rotor punching sheet is designed as a sector, the expansion angle of the sector is 180 / p degrees, p is the number of pole pairs, and the rotor structure under one pole is symmetrical about the central axis X of the sector, the left boundary straight line of the sector is Y, the part of the inner circle of the motor stator corresponding to the one pole is arc L1, the center of the circle is the center of the motor shaft O, the radius of the arc L1 is R1, the arc L1 is offset toward the center of the circle by the air gap length g1 to obtain the outer circle boundary arc L2 of the motor rotor, the radius of L2 is R2, R2 = R1-g1;

[0068] S2: The arc L2 is offset toward the center by a distance g2 to obtain the arc L3, whose radius is R3, R3 = R2-g2;

[0069] S3: The central axis X rotates around O toward the boundary line Y by an angle a1 / 2 to obtain a straight line OA, which intersects L3 at point A.

[0070] S4: Draw a straight line L4 through point A, perpendicular to the center axis X, and the distance from point A to the center axis is b1; L4 is offset toward the center of the circle by a distance h1 to obtain a straight line L5, which intersects the center axis at point K;

[0071] Go to S5.1 or S6.1 or S7.1;

[0072] S5.1: The center axis X is offset toward the boundary line Y by a distance g3 / 2 to obtain line segment JH, which intersects L4 at point H and intersects L5 at point J;

[0073] S5.2: Line JH is offset by a distance b2 in the Y direction of the boundary line to obtain line segment DE, which intersects L5 at point D. The length of DJ is b2, the length of DE is g4, and the direction from point D to point E points to the side of line L4;

[0074] S5.3: Draw a line segment EF through point E that is perpendicular to DE. The length of EF is g5. The direction from point E to point F points to the side of boundary line Y. Draw a line segment FG through point F that is perpendicular to EF. The length of FG is g4. The direction from point F to point G points to the side of the center of the circle.

[0075] S5.4: The boundary line Y is rotated about the center O in the direction of the central axis X by an angle a2 to obtain the line OB. The line OB intersects L3 and point B. A line BC is drawn through point B and parallel to the boundary line Y. A line perpendicular to BC is drawn through point G, and the foot of the perpendicular is point C.

[0076] S5.5: The polygon BCGFEDJHA forms a hole, which is mirrored about the central axis to form two holes for inserting permanent magnets with rectangular cross-sections. The permanent magnets in the holes have the same specifications, and the corners of each hole are rounded;

[0077] Go to step S8;

[0078] S6.1: The central axis X intersects the straight line L4 and the straight line L5 at points M and K;

[0079] S6.2: The center axis X is offset toward the boundary line Y by a distance b3 / 2 to obtain line segment QR, which intersects L4 at point R and intersects L5 at point Q;

[0080] S6.3: QR is offset by a distance g3 in the Y direction of the boundary line to obtain a line segment PN, which intersects L4 at point N and intersects L5 at point P;

[0081] S6.4: PN is offset by a distance b3 in the Y direction of the boundary line to obtain line segment DE, which intersects L5 at point D. The length of DJ is b2, the length of DE is g4, and the direction from point D to point E points to the side of line L4;

[0082] S6.5: Draw a line segment EF through point E that is perpendicular to DE. The length of EF is g5. The direction from point E to point F points to the side of boundary line Y. Draw a line segment FG through point F that is perpendicular to EF. The length of FG is g4. The direction from point F to point G points to the side of the center of the circle.

[0083] S6.6: The boundary line Y is rotated about the center O in the direction of the central axis X by an angle a2 to obtain the line OB. The line OB intersects L3 and point B. A line BC is drawn through point B and parallel to the boundary line Y. A line perpendicular to BC is drawn through point G, and the foot of the perpendicular is point C.

[0084] S6.7: The polygon BCGFEDPNA forms one hole, and the quadrilateral RQKM forms another hole. The above two holes are mirrored about the central axis to form three holes for inserting permanent magnets with rectangular cross-sections. The permanent magnets in the holes have the same specifications, and the sharp corners of each hole are rounded;

[0085] Go to step S8;

[0086] S7.1: The central axis X intersects the straight line L4 and the straight line L5 at points M and K;

[0087] S7.2: Line KM is offset in the Y direction of the boundary line by a distance g3 / 2 to obtain line segment JH, which intersects L4 at point H and intersects L5 at point J;

[0088] S7.3: Line JH is offset by a distance b4 in the Y direction of the boundary line to obtain line segment QR, which intersects L4 at point R and intersects L5 at point Q;

[0089] S7.4: Line QR is offset by a distance g3 in the Y direction of the boundary line to obtain line segment PN, which intersects L4 at point N and intersects L5 at point P;

[0090] S7.5: PN is offset by a distance b4 in the Y direction of the boundary line to obtain line segment DE, which intersects L5 at point D. The length of DJ is b2, the length of DE is g4, and the direction from point D to point E points to the side of line L4;

[0091] S7.6: Draw a line segment EF through point E that is perpendicular to DE. The length of EF is g5. The direction from point E to point F points to the side of boundary line Y. Draw a line segment FG through point F that is perpendicular to EF. The length of FG is g4. The direction from point F to point G points to the side of the center of the circle.

[0092] S7.7: The boundary line Y is rotated about the center O in the direction of the central axis X by an angle a2 to obtain the line OB. The line OB intersects L3 and point B. A line BC is drawn through point B and parallel to the boundary line Y. A line perpendicular to BC is drawn through point G, with the foot of the perpendicular being point C.

[0093] S7.8: The polygon BCGFEDPNA forms one hole, and the quadrilateral RQJH forms another hole. The above two holes are mirrored about the central axis to form four holes for inserting permanent magnets with rectangular cross-sections. The permanent magnets in the holes have the same specifications, and the sharp corners of each hole are rounded;

[0094] S8: The hole structure under other residual poles is replicated through a circular array.

[0095] The rotor punching provided by the present invention is designed according to the following steps: according to symmetry, one pole of the motor rotor punching is designed as a sector, the expansion angle of the sector is 180 / p degrees, and p is the number of pole pairs; the central axis of the sector, the boundary straight line and the inner arc line of the motor stator are used as references, and the boundary position of the hole is drawn by geometric drawing method, and the formed hole is used to insert the permanent magnet with a rectangular cross section, and the specifications of the permanent magnets in the hole are the same. The present invention can quickly design serialized high-efficiency permanent magnet rotor punchings, improve the level of standardization and serialization, and thus reduce the cost of the motor; because the outer area of ​​the pole part is small, the stress of the rotor reinforcement rib is small; the rotor can open a larger lightening hole to reduce the weight of the rotor; the width of the one-line permanent magnet is small, which reduces the stator magnetic density, thereby reducing the stator iron loss; the optimization of the magnetic bridge position can reduce the rotor no-load cogging torque and torque fluctuation under load; the rotor core of the punching stacked by the present invention can be inserted with a rectangular cross-section permanent magnet, reducing the manufacturing and installation costs of the permanent magnet.

[0096] Optionally, the straight line L5 is offset by a distance h2 toward the center of the circle to obtain a straight line L6; the inner arc line L8 of the rotor is offset by a distance h3 away from the center of the circle to obtain an arc line L7; a straight line L9 is drawn through point K, and the angle between L9 and the central axis X is a3, and a3 is 40 degrees to 50 degrees; the boundary straight line Y is offset by a distance h4 toward the central axis X to obtain a straight line L 10 The above straight line L6, arc L7, straight line L9, straight line L 10 and the center axis X, the hole is mirrored about the center axis X to form a large hole, where the fillet r1 between L6 and L9, L 10 and L9, r2, L7 and L 10 The corners r3 are rounded between them, and the above-mentioned hole structure under other residual poles is replicated through a circular array; the value range of h2 is: 0.15×R1 / p to 0.4×R1 / p, the value range of h3 is: 0.15×R1 / p to 0.5×R1 / p, the value range of h4 is: 0.05×R1 / p to 0.5×R1 / p, the value range of r1 is: 0.04×R1 / p to 0.4×R1 / p, the value range of r2 is: 0.04×R1 / p to 0.2×R1 / p, and the value range of r3 is: 0.04×R1 / p to 0.2×R1 / p.

[0097] Optionally, in S1, the pole pair number p is one of the following: 2, 3, 4; in S1, the value range of the radius R1 is: 25 mm to 220 mm.

[0098] Optionally, in S2, the value range of g2 is: g1 to 2×g1; in S3, the value range of a1 is: 0.64×180 / p degrees to 0.8×180 / p degrees.

[0099] Optionally, in S4, the value range of h1 is: 3×g1 to 5×g1; in S5.1, S6.3 and S7.2, the value range of g3 is: 0 or 0.5 mm to 2 mm.

[0100] Optionally, in S5.2, the value range of b2 is: 0.85×b1 to 0.91×b1; in S5.2, S6.4 and S7.5, the value range of g4 is: 0.4mm to 2mm; in S5.3, S6.5 and S7.6, the value range of g5 is: 0.7mm to 2mm.

[0101] Optionally, in S5.4, S6.6 and S7.7, the value range of a2 is: 0.024×180 / p degrees to 0.026×180 / p degrees.

[0102] Optionally, in S6.2, the value range of b3 is: 0.56×b1 to 0.61×b1; in S7.3, the value range of b4 is: 0.42×b1 to 0.46×b1.

[0103] Optionally, the cavity where the permanent magnet slot is located is filled with insulating material to reduce the maximum stress of the rotor.

[0104] In summary, the permanent magnet synchronous motor made by the punching sheets of the present invention has a smaller width of the straight permanent magnet and a lower air gap magnetic density, thereby reducing the core loss of the stator teeth and yoke and improving the efficiency of the motor. The permanent magnet synchronous motor made by the punching sheets of the present invention has only one rectangular cross-section permanent magnet specification, which reduces the number of permanent magnet specifications and reduces the manufacturing cost; the permanent magnet synchronous motor made by the punching sheets of the present invention has smaller fluctuations in no-load tooth slot torque and load torque, and the peak-to-peak value of the load torque is not greater than 5% of the rated torque; the permanent magnet slots of the punching sheets of the present invention are close to the outer circle of the rotor, and the rotor core area outside the permanent magnet slots is very small, so that the stress on the rotor reinforcement ribs is small, which is convenient for increasing the maximum speed of the motor or expanding the outer diameter of the motor to increase the motor capacity; the number of permanent magnet holes per pole of the rotor made by the punching sheets of the present invention can be 1, 2, 3, or 4, and 1, 2, 3, or 4 axial rows can be placed respectively. The permanent magnets of the present invention are arranged in a row, so that motor punchings of different sizes have a smaller magnetic bridge width and the permanent magnets have a smaller aspect ratio; the rotor made by the punchings of the present invention has a larger lightening hole, which is convenient for reducing the weight of the rotor, reducing the rotor bearing load, and is beneficial to increasing the maximum speed of the motor or increasing the motor capacity; the punchings of the present invention can be used to design the rotor in segmented pole staggering to form the same effect as the stator skew slot, further reducing the no-load tooth slot torque and the torque fluctuation under load, and realizing higher-precision speed and position control; the design steps of the punchings of the present invention can be compiled into computer software, and the optional parameters are used as optimization variables. Through the optimization algorithm, the optional parameters with the best performance such as efficiency and torque fluctuation are obtained.

[0105] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable ordinary technicians in the field to understand the content of the present invention and implement it. They cannot be used to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A rotor punching sheet for a high-efficiency permanent magnet synchronous motor, characterized in that: The rotor punching is designed by the following steps: S1: According to symmetry, one pole of the motor rotor punching sheet is designed as a sector, the expansion angle of the sector is 180 / p degrees, p is the number of pole pairs, and the rotor structure under one pole is symmetrical about the central axis X of the sector, the left boundary straight line of the sector is Y, the part of the inner circle of the motor stator corresponding to the one pole is arc L1, the center of the circle is the center of the motor shaft O, the radius of the arc L1 is R1, the arc L1 is offset toward the center of the circle by the air gap length g1 to obtain the outer circle boundary arc L2 of the motor rotor, the radius of L2 is R2, R2 = R1-g1; S2: The arc L2 is offset toward the center by a distance g2 to obtain the arc L3, whose radius is R3, R3 = R2-g2; S3: The central axis X rotates around O toward the boundary line Y by an angle a1 / 2 to obtain a straight line OA, which intersects L3 at point A. S4: Draw a straight line L4 through point A, perpendicular to the center axis X, and the distance from point A to the center axis is b1; L4 is offset toward the center of the circle by a distance h1 to obtain a straight line L5, which intersects the center axis at point K; Go to S5.1 or S6.1 or S7.1; S5.1: The center axis X is offset toward the boundary line Y by a distance g3 / 2 to obtain line segment JH, which intersects L4 at point H and intersects L5 at point J; S5.2: Line JH is offset by a distance b2 in the Y direction of the boundary line to obtain line segment DE, which intersects L5 at point D. The length of DJ is b2, the length of DE is g4, and the direction from point D to point E points to the side of line L4; S5.3: Draw a line segment EF through point E that is perpendicular to DE. The length of EF is g5. The direction from point E to point F points to the side of boundary line Y. Draw a line segment FG through point F that is perpendicular to EF. The length of FG is g4. The direction from point F to point G points to the side of the center of the circle. S5.4: The boundary line Y is rotated about the center O in the direction of the central axis X by an angle a2 to obtain the line OB. The line OB intersects L3 and point B. A line BC is drawn through point B and parallel to the boundary line Y. A line perpendicular to BC is drawn through point G, and the foot of the perpendicular is point C. S5.5: The polygon BCGFEDJHA forms a hole, which is mirrored about the central axis to form two holes for inserting permanent magnets with rectangular cross-sections. The permanent magnets in the holes have the same specifications, and the corners of each hole are rounded; Go to step S8; S6.1: The central axis X intersects the straight line L4 and the straight line L5 at points M and K; S6.2: The center axis X is offset toward the boundary line Y by a distance b3 / 2 to obtain line segment QR, which intersects L4 at point R and intersects L5 at point Q; S6.3: QR is offset by a distance g3 in the Y direction of the boundary line to obtain a line segment PN, which intersects L4 at point N and intersects L5 at point P; S6.4: PN is offset by a distance b3 in the Y direction of the boundary line to obtain line segment DE, which intersects L5 at point D. The length of DJ is b2, the length of DE is g4, and the direction from point D to point E points to the side of line L4; S6.5: Draw a line segment EF through point E that is perpendicular to DE. The length of EF is g5. The direction from point E to point F points to the side of boundary line Y. Draw a line segment FG through point F that is perpendicular to EF. The length of FG is g4. The direction from point F to point G points to the side of the center of the circle. S6.6: The boundary line Y is rotated about the center O in the direction of the central axis X by an angle a2 to obtain the line OB. The line OB intersects L3 and point B. A line BC is drawn through point B and parallel to the boundary line Y. A line perpendicular to BC is drawn through point G, and the foot of the perpendicular is point C. S6.7: The polygon BCGFEDPNA forms one hole, and the quadrilateral RQKM forms another hole. The above two holes are mirrored about the central axis to form three holes for inserting permanent magnets with rectangular cross-sections. The permanent magnets in the holes have the same specifications, and the sharp corners of each hole are rounded; Go to step S8; S7.1: The central axis X intersects the straight line L4 and the straight line L5 at points M and K; S7.2: Line KM is offset in the Y direction of the boundary line by a distance g3 / 2 to obtain line segment JH, which intersects L4 at point H and intersects L5 at point J; S7.3: Line JH is offset by a distance b4 in the Y direction of the boundary line to obtain line segment QR, which intersects L4 at point R and intersects L5 at point Q; S7.4: Line QR is offset by a distance g3 in the Y direction of the boundary line to obtain line segment PN, which intersects L4 at point N and intersects L5 at point P; S7.5: PN is offset by a distance b4 in the Y direction of the boundary line to obtain line segment DE, which intersects L5 at point D. The length of DJ is b2, the length of DE is g4, and the direction from point D to point E points to the side of line L4; S7.6: Draw a line segment EF through point E that is perpendicular to DE. The length of EF is g5. The direction from point E to point F points to the side of boundary line Y. Draw a line segment FG through point F that is perpendicular to EF. The length of FG is g4. The direction from point F to point G points to the side of the center of the circle. S7.7: The boundary line Y is rotated about the center O in the direction of the central axis X by an angle a2 to obtain the line OB. The line OB intersects L3 and point B. A line BC is drawn through point B and parallel to the boundary line Y. A line perpendicular to BC is drawn through point G, with the foot of the perpendicular being point C. S7.8: The polygon BCGFEDPNA forms one hole, and the quadrilateral RQJH forms another hole. The above two holes are mirrored about the central axis to form four holes for inserting permanent magnets with rectangular cross-sections. The permanent magnets in the holes have the same specifications, and the sharp corners of each hole are rounded; S8: The hole structure under other residual poles is replicated through a circular array.

2. The rotor punching sheet of the high-efficiency permanent magnet synchronous motor according to claim 1 is characterized in that: Line L5 is offset by a distance h2 toward the center of the circle to obtain line L6; the inner arc line L8 of the rotor is offset by a distance h3 away from the center of the circle to obtain arc line L7; a line L9 is drawn through point K, and the angle between L9 and the center axis X is a3, and a3 is 40 to 50 degrees; the boundary line Y is offset by a distance h4 toward the center axis X to obtain line L 10 The above straight line L6, arc L7, straight line L9, straight line L 10 and the center axis X, the hole is mirrored about the center axis X to form a large hole, where the fillet r1 between L6 and L9, L 10 and L9, r2, L7 and L 10 The corners r3 are rounded and the above-mentioned hole structures under other remaining poles are replicated through a circular array.

3. The rotor punching sheet of the high-efficiency permanent magnet synchronous motor according to claim 1, characterized in that: In S1, the pole pair number p is one of the following: 2, 3, 4; in S1, the radius R1 ranges from 25 mm to 220 mm.

4. The rotor punching sheet of the high-efficiency permanent magnet synchronous motor according to claim 1, characterized in that: In S2, the value range of g2 is: g1 to 2×g1; in S3, the value range of a1 is: 0.64×180 / p degrees to 0.8×180 / p degrees.

5. The rotor punching sheet of the high-efficiency permanent magnet synchronous motor according to claim 1, characterized in that: In S4, the value range of h1 is: 3×g1 to 5×g1; in S5.1, S6.3 and S7.2, the value range of g3 is: 0 or 0.5mm to 2mm.

6. The rotor punching sheet of the high-efficiency permanent magnet synchronous motor according to claim 1, characterized in that: In S5.2, the value range of b2 is: 0.85×b1 to 0.91×b1; in S5.2, S6.4 and S7.5, the value range of g4 is: 0.4mm to 2mm; In S5.3, S6.5 and S7.6, the value range of g5 is: 0.7mm to 2mm.

7. The rotor punching sheet of the high-efficiency permanent magnet synchronous motor according to claim 1, characterized in that: In S5.4, S6.6 and S7.7, the value range of a2 is: 0.024×180 / p degree to 0.026×180 / p degree.

8. The rotor punching sheet of the high-efficiency permanent magnet synchronous motor according to claim 1, characterized in that: In S6.2, the value range of b3 is: 0.56×b1 to 0.61×b1; in S7.3, the value range of b4 is: 0.42×b1 to 0.46×b1.

9. The rotor punching sheet of the high-efficiency permanent magnet synchronous motor according to claim 2, characterized in that: The value range of h2 is: 0.15×R1 / p to 0.4×R1 / p, the value range of h3 is: 0.15×R1 / p to 0.5×R1 / p, the value range of h4 is: 0.05×R1 / p to 0.5×R1 / p, the value range of r1 is: 0.04×R1 / p to 0.4×R1 / p, the value range of r2 is: 0.04×R1 / p to 0.2×R1 / p, and the value range of r3 is: 0.04×R1 / p to 0.2×R1 / p.

10. The rotor punching sheet of the high-efficiency permanent magnet synchronous motor according to claim 1, characterized in that: The cavity where the permanent magnet slot is located is filled with insulating material to reduce the maximum stress of the rotor.

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