Iron core structure, rotor assembly, motor and compressor

Abstract

The present invention provides an iron core structure, a rotor assembly, a motor and a compressor. The iron core structure includes: an iron core body; multiple groups of magnetic steel grooves that are evenly distributed along the circumference of the iron core body and are used to accommodate permanent magnets; multiple groups of first magnetic isolation holes respectively arranged between the magnetic steel grooves and the outer circumference of the iron core body. One end of the magnetic steel groove far from the D-axis is the first end, and the first magnetic isolation hole is adjacent to the first end; the first magnetic isolation hole is L-shaped, and one side of the L-shape is arranged along the radial direction of the iron core body. In the iron core structure of the present invention, by respectively arranging L-shaped first magnetic isolation holes at both ends far from the D-axis under one magnetic pole, the magnetic circuit of the motor is optimized without affecting the magnitude of the motor output torque, and the electromagnetic force amplitude of the rotor iron core is reduced. It can also reduce the harmonic content in the air-gap magnetic density, further reduce the iron loss of the motor, improve the vibration noise of the motor, and thus reduce the overall noise of the compressor.

Description

Technical Field

[0001] The present invention belongs to the technical field of motors, and particularly relates to an iron core structure, a rotor assembly, a motor and a compressor. Background Art

[0002] As a core component of a compressor, the efficiency and noise problems of the motor directly affect the overall performance of the compressor. In the prior art, a rotor core composed of multiple arc segments is adopted in the rotor structure, including multiple inclined slits arranged outside the magnetic steel slots, which improves the armature iron loss and reduces the electromagnetic noise. The outer edge of the rotor is composed of multiple arc segments, and the setting of different arc radius sizes is likely to cause too large an air gap between the stator and the rotor, resulting in a large loss of motor torque, a decrease in motor output, and a rapid attenuation of motor efficiency under a large torque load. At the same time, the inclined slit structure forms a certain angle with the permanent magnet, and the slit width in the magnetization direction of the permanent magnet has a certain blocking effect on the magnetic flux, resulting in a reduction in the magnetic flux of the motor and affecting the efficiency and electromagnetic noise. Summary of the Invention

[0003] Therefore, the technical problem to be solved by the present invention is that in the prior art, optimizing the motor magnetic circuit to reduce the electromagnetic force will cause a decrease in the output torque capacity and a reduction in motor efficiency. Thus, an iron core structure, a rotor assembly, a motor and a compressor are provided.

[0004] To solve the above problems, the present invention provides an iron core structure, including:

[0005] An iron core body;

[0006] Multiple groups of magnetic steel slots that are evenly distributed along the circumferential direction of the iron core body and are used to accommodate permanent magnets;

[0007] Multiple groups of first magnetic isolation holes respectively arranged between the magnetic steel slots and the outer circumference of the iron core body. One end of the magnetic steel slot far from the D-axis is the first end, and the first magnetic isolation hole is adjacent to the first end;

[0008] The first magnetic isolation hole is L-shaped, and one side of the L-shape is arranged along the radial direction of the iron core body.

[0009] The object of the present invention and the technical measures for solving its technical problems can be further realized by the following technical measures.

[0010] Preferably, the iron core structure further includes multiple groups of second magnetic isolation holes, and the second magnetic isolation holes are adjacent to the first magnetic isolation holes and are located on the side of the first magnetic isolation holes far from the D-axis.

[0011] Preferably, the first magnetic isolation hole includes a first hole portion and a second hole portion that form an L-shape. The first hole portion is arranged along the radial direction of the iron core body, and the second hole portion is arranged at the end of the first hole portion close to the central hole of the iron core body, or the second hole portion is arranged at the end of the first hole portion far from the central hole of the iron core body.

[0012] Preferably, the second hole portion extends away from the D axis from the first hole portion, or the second hole portion extends toward the D axis from the first hole portion.

[0013] Preferably, the included angle between the first hole portion and the second hole portion is R, satisfying R = 5° to 155°.

[0014] Preferably, the width of the first hole portion in the circumferential direction of the iron core body is b1, the width of the second hole portion in the circumferential direction of the iron core body is b2, the minimum distance from the first magnetic isolation hole to the D axis is G, the minimum spacing distance between the first magnetic isolation hole and the magnetic steel groove is J, the unilateral assembly clearance between the permanent magnet and the magnetic steel groove is g, the thickness of the permanent magnet is Hd, and the length of the permanent magnet is Ld, satisfying

[0015]

[0016] and / or

[0017]

[0018] Preferably, the height of the first hole portion in the radial direction of the iron core body is a1, the height of the second hole portion in the radial direction of the iron core body is a2, the included angle between the first hole portion and the second hole portion is R, the included angle between the magnetic steel groove and the D axis is S, the thickness of the permanent magnet is Hd, and the length of the permanent magnet is Ld, satisfying

[0019] 0 < a1 < 25 × Ld × cosS × Hd × sinR;

[0020] and / or

[0021] 0 < (a1 - a2) < 25 × Ld × cosS × Hd × sinR.

[0022] Preferably, the side of the first magnetic isolation hole facing the D axis is the first hole edge, and the included angle between the first hole edge and the D axis is T, satisfying T = 0° to 80°.

[0023] Preferably, the included angle between the magnetic steel groove and the D axis is S, satisfying S = 10° to 90°.

[0024] Preferably, the minimum distance between the second magnetic isolation hole and the magnetic steel groove is c1, the minimum distance between the second magnetic isolation hole and the end of the first magnetic isolation hole facing the central hole of the iron core body is c2, the minimum distance between the second magnetic isolation hole and the end of the first magnetic isolation hole facing the outer circumference of the iron core body is c3, the minimum spacing distance between the first magnetic isolation hole and the magnetic steel groove is J, the minimum distance from the first magnetic isolation hole to the D axis is G, the unilateral assembly clearance between the permanent magnet and the magnetic steel groove is g, the thickness of the permanent magnet is Hd, and the length of the permanent magnet is Ld, satisfying

[0025]

[0026] and / or

[0027]

[0028] and / or,

[0029]

[0030] Preferably, the second magnetic isolation hole is quadrilateral.

[0031] Preferably, the second magnetic isolation hole is a parallelogram, and the angle between the quadrilateral and the outer periphery of the iron core body near the D-axis is an acute angle.

[0032] Preferably, a third magnetic isolation hole is further provided at the first end of the magnet slot.

[0033] Preferably, one end of the third magnetic isolation hole communicates with the first end of the magnet slot, the other end faces the D-axis, and the angle between the third magnetic isolation hole and the magnet slot is Q.

[0034] Preferably, Q = 5° to 175° is satisfied.

[0035] Preferably, when the iron core structure includes the second magnetic isolation hole, the distance between the third magnetic isolation hole and the second magnetic isolation hole is M;

[0036] When the first magnetic isolation hole includes a first hole portion and a second hole portion forming an L shape, the width of the first hole portion along the circumferential direction of the iron core body is b1, the width of the second hole portion along the circumferential direction of the iron core body is b2, and the minimum distance between the first magnetic isolation hole and the magnet slot is J, the minimum distance between the third magnetic isolation hole and the end of the first magnetic isolation hole facing the axis hole of the iron core body is N, and it satisfies,

[0037]

[0038] and / or,

[0039]

[0040] Preferably, a V-shaped groove is provided on the outer peripheral surface corresponding to the Q-axis of the iron core body, and both sides of the V-shaped groove are parallel to the magnet slot.

[0041] Preferably, at least two first magnetic isolation holes are provided at each pole of the iron core body.

[0042] Preferably, the permanent magnet is any one of a rare earth permanent magnet, a ferrite permanent magnet, and a hybrid material permanent magnet.

[0043] A rotor assembly adopts the above iron core structure.

[0044] An electric motor adopts the above iron core structure.

[0045] A compressor adopts the above iron core structure.

[0046] The iron core structure, rotor assembly, motor and compressor provided by the present invention have at least the following beneficial effects:

[0047] For the iron core structure of the present invention, by respectively arranging L-shaped first magnetic isolation holes at both ends far from the D-axis under one magnetic pole, without affecting the magnitude of the motor output torque, the motor magnetic circuit is optimized, and the electromagnetic force amplitude of the rotor core is reduced. It can also reduce the harmonic content in the air-gap magnetic density, further reduce the iron loss of the motor, improve the motor vibration and noise, and thus reduce the overall noise of the compressor. At the same time, the L-shaped magnetic isolation hole can also be used as a flow-through hole to increase the flow-through area of the rotor core and improve the heat dissipation capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 is a schematic structural diagram of the iron core structure of an embodiment of the present invention;

[0049] Figure 2 is Figure 1 an enlarged view of the structure at A in

[0050] Figure 3 is Shape 1 of the first magnetic isolation hole in an embodiment of the present invention;

[0051] Figure 4 is Shape 2 of the first magnetic isolation hole in an embodiment of the present invention;

[0052] Figure 5 is Shape 3 of the first magnetic isolation hole in an embodiment of the present invention;

[0053] Figure 6 is Shape 4 of the first magnetic isolation hole in an embodiment of the present invention;

[0054] Figure 7 is a schematic structural diagram of the V-shaped groove structure in an embodiment of the present invention;

[0055] Figure 8 is a schematic structural diagram of at least two groups of first magnetic isolation holes in an embodiment of the present invention;

[0056] Figure 9 is a comparison diagram of the electromagnetic forces of the motor using the iron core structure of the present application and the existing motor

[0057] Figure 10 is a comparison diagram of the iron losses of the motor using the iron core structure of the present application and the existing motor;

[0058] Figure 11 is a comparison diagram of the motor efficiencies of the motor using the iron core structure of the present application and the existing motor

[0059] Figure 12 is a comparison diagram of the noises of the compressor using the iron core structure of the present application and the existing compressor.

[0060] The reference numerals are shown as:

[0061] 1. Iron core body; 2. Magnet steel groove; 3. Permanent magnet; 4. First magnetic isolation hole; 5. Second magnetic isolation hole; 6. First hole part; 7. Second hole part; 8. First hole edge; 9. Axis hole; 10. First end; 11. Third magnetic isolation hole; 12. V-shaped groove. Specific embodiments

[0062] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0063] Combined with Figures 1 to 6 As shown, this embodiment provides an iron core structure, including: an iron core body 1; multiple groups of magnet steel grooves 2 that are evenly distributed along the circumference of the iron core body 1 and are used to accommodate permanent magnets 3, and the N and S poles of the permanent magnets 3 in the magnet steel grooves 3 are arranged alternately; multiple groups of first magnetic isolation holes 4 respectively arranged between the magnet steel grooves 2 and the outer circumference of the iron core body 1, one end of the magnet steel groove 2 away from the D axis is the first end 10, and the first magnetic isolation holes 4 are adjacent to the first end 10; the first magnetic isolation holes 4 are L-shaped, and one side of the L shape is arranged along the radial direction of the iron core body 1, and the first magnetic isolation holes 4 under each pole are symmetric about the D axis.

[0064] In this embodiment, the D axis and Q axis are a form of coordinate axes of a motor. The central symmetry line of each magnetic pole is the D axis, also known as the direct axis, and the Q axis is on the perpendicular bisector between two adjacent magnetic poles, also known as the quadrature axis.

[0065] For the iron core structure of the embodiment of the present invention, by respectively arranging L-shaped first magnetic isolation holes at both ends away from the D axis under one magnetic pole, it can optimize the magnetic circuit of the motor, but does not affect the magnitude of the motor output torque, and reduces the main order and main multiple frequency electromagnetic forces of the rotor iron core. For example, in a nine-slot six-pole concentrated winding motor, adding L-shaped magnetic isolation holes can reduce the electromagnetic force amplitudes of the 3rd order six-fold frequency and 0th order 18-fold frequency. It can also reduce the harmonic content in the air gap magnetic density, further reduce the iron loss of the motor, improve the vibration noise of the motor, and thus reduce the overall noise of the compressor. At the same time, the L-shaped magnetic isolation holes can also be used as circulation holes, increasing the circulation area of the rotor iron core and improving the heat dissipation capacity.

[0066] Preferably, combined with Figures 1 - 6As shown, the first magnetic isolation hole 4 includes a first hole portion 6 and a second hole portion 7 that form an L shape. The first hole portion 6 is arranged along the radial direction of the iron core body 1, and the second hole portion 7 is arranged at the end of the first hole portion 6 close to the axial center hole 9 of the iron core body 1, or the second hole portion 7 is arranged at the end of the first hole portion 6 far from the axial center hole 9 of the iron core body 1. Alternatively, the second hole portion extends from the first hole portion in a direction away from the D axis, or the second hole portion extends from the first hole portion in a direction close to the D axis.

[0067] By adjusting the lengths of the two sides of L, the width, and the included angle R between the two, these several shapes can optimize the magnetic circuit, improve the air-gap magnetic density waveform, and optimize the electromagnetic force amplitude, so as to reduce the load torque ripple of the motor, reduce the load noise of the motor, and improve the motor efficiency.

[0068] Preferably, the included angle between the first hole portion 6 and the second hole portion 7 is R, satisfying R = 5° - 155°. If R < 5°, the shape of the magnetic isolation hole is close to a triangle, and it can be changed to a triangle for processability, but the effect on reducing the electromagnetic force amplitude is weak; if R > 155°, the shape of the magnetic isolation hole is close to a straight line or a rectangle, and it can be changed to a straight line or a rectangle for processability, but the effect on reducing the electromagnetic force amplitude is not good, and it will also reduce the output torque and the motor efficiency; therefore, the optimal value range of R is 5° - 155°.

[0069] Preferably, the side of the first magnetic isolation hole 4 facing the D axis is the first hole edge 8, and the included angle between the first hole edge 8 and the D axis is T, satisfying T = 0° - 80°. Within this range, the first magnetic isolation hole 4 can guide and change the position and direction of the magnetic circuit flowing through the rotor core, reduce the magnetic potential harmonics generated by the interaction between the stator magnetic chain and the rotor magnetic circuit, and reduce the electromagnetic noise.

[0070] Preferably, the included angle between the magnetic steel groove 2 and the D axis is S, satisfying S = 10° - 90°. Within this range, the air-gap magnetic density waveform and the magnetic force line gathering ability at the center of the magnetic pole can both reach better effects.

[0071] Preferably, the iron core structure further includes multiple groups of second magnetic isolation holes 5. The second magnetic isolation holes 5 are adjacent to the first magnetic isolation holes 4 and are located on the side of the first magnetic isolation holes 4 far from the D axis. The second magnetic isolation holes 5 are quadrilaterals.

[0072] Preferably, the second magnetic isolation holes 5 are parallelograms, and the included angle between the side close to the D axis and the outer periphery of the iron core body 1 in the quadrilateral is an acute angle. Such a structure of the second magnetic isolation holes 5 can optimize the electromagnetic force and make the air gap sinusoidal.

[0073] This embodiment can release the magnetic force lines gathered by the two symmetric L-shaped first magnetic isolation holes 4, and hand them over to the second magnetic isolation holes 5 for further arrangement, which can optimize the magnetic force line distribution near both ends of the magnetic pole, reduce the back electromotive force harmonics, and reduce the iron loss of the motor.

[0074] Preferably, a third magnetic isolation hole 11 is further provided at the first end portion 10 of the magnet slot 2. Preferably, one end of the third magnetic isolation hole 11 communicates with the first end portion 10 of the magnet slot 2, and the other end faces the D-axis. The included angle between the third magnetic isolation hole 11 and the magnet slot 2 is Q. The function of the third magnetic isolation hole 11 is to reduce inter-pole magnetic leakage and improve the output torque.

[0075] Preferably, the included angle Q between the third magnetic isolation hole 11 and the magnet slot 2 satisfies Q = 5° to 175°. Within this range, the horn-shaped air slot can guide and change the position and direction of the magnetic circuit flowing through the rotor core, reduce the magnetic potential harmonics generated by the interaction between the stator magnetic flux and the rotor magnetic circuit, and reduce the electromagnetic noise.

[0076] Preferably, the width of the first hole portion 6 in the circumferential direction of the iron core body 1 is b1, the width of the second hole portion 7 in the circumferential direction of the iron core body 1 is b2, the minimum distance from the first magnetic isolation hole 4 to the D-axis is G, the minimum spacing distance between the first magnetic isolation hole 4 and the magnet slot 2 is J, the unilateral assembly clearance between the permanent magnet 3 and the magnet slot 2 is g, the thickness of the permanent magnet 3 is Hd, and the length of the permanent magnet 3 is Ld, satisfying

[0077]

[0078] and / or

[0079]

[0080] If the values of b1 and b2 are outside this range, it will cause an ineffective magnetic density to be formed under the permanent magnetic poles or the magnetic lines of force to be too dense locally in the rotor, resulting in low utilization rate of the permanent magnet and increased iron loss of the motor; when the values of b1 and b2 are within this range, it can both form an effective magnetic density under the permanent magnetic poles and avoid blocking too many magnetic lines of force, improving the utilization rate of the permanent magnet.

[0081] Preferably, the height of the first hole portion 6 in the radial direction of the iron core body 1 is a1, the height of the second hole portion 7 in the radial direction of the iron core body 1 is a2, the included angle between the first hole portion 6 and the second hole portion 7 is R, the included angle between the magnet slot 2 and the D-axis is S, the thickness of the permanent magnet 3 is Hd, and the length of the permanent magnet 3 is Ld, satisfying

[0082] 0 < a1 < 25 × Ld × cosS × Hd × sin R;

[0083] and / or

[0084] 0 < (a1 - a2) < 25 × Ld × cosS × Hd × sinR.

[0085] If the values of a1 and a2 exceed this range, excessive height will block the flow of magnetic lines of force, reduce the output torque, and increase torque ripple. If the height is too small, its function of modulating magnetic lines of force will be weakened, and the harmonic content of the air-gap magnetic density cannot be effectively reduced. When the values of a1 and a2 are within this range, the air-gap magnetic density at the center of the magnetic pole can be appropriately weakened, making the waveform of the entire magnetic density just close to a sine wave with the minimum harmonic content.

[0086] Preferably, the minimum distance between the second magnetic isolation hole 5 and the magnetic steel groove 2 is c1, the minimum distance between the second magnetic isolation hole 5 and the end of the first magnetic isolation hole 4 facing the axis hole 9 of the iron core body 1 is c2, the minimum distance between the second magnetic isolation hole 5 and the end of the first magnetic isolation hole 4 facing the outer circumference of the iron core body 1 is c3, the minimum spacing distance between the first magnetic isolation hole 4 and the magnetic steel groove 2 is J, the minimum distance from the first magnetic isolation hole 4 to the D axis is G, the unilateral assembly clearance between the permanent magnet 3 and the magnetic steel groove 2 is g, the thickness of the permanent magnet 3 is Hd, and the length of the permanent magnet 3 is Ld, satisfying

[0087]

[0088] and / or

[0089]

[0090] and / or

[0091]

[0092] By adjusting the distances between the quadrilateral second magnetic isolation hole 5, the L-shaped first magnetic isolation hole 4, and the magnetic steel groove 2, the direction of the magnetic lines of force can be changed, optimizing the magnetic circuit of the motor, reducing the harmonic content of the magnetic density on the stator and rotor iron cores, effectively reducing the harmonic content of the electromagnetic force, and reducing the load noise of the motor. Through the above method, it is also possible to effectively improve the problem of increased torque pulsation caused by rich harmonic content of the back electromotive force of the motor, significantly reduce the harmonic content of the back electromotive force, reduce the iron loss of the motor, and improve the efficiency of the motor.

[0093] Preferably, when the iron core structure includes the second magnetic isolation hole 5, the distance between the third magnetic isolation hole 11 and the second magnetic isolation hole 5 is M; when the first magnetic isolation hole 4 includes a first hole portion 6 and a second hole portion 7 forming an L shape, and the width of the first hole portion 6 in the circumferential direction of the iron core body 1 is b1, the width of the second hole portion 7 in the circumferential direction of the iron core body 1 is b2, and the minimum spacing distance between the first magnetic isolation hole 4 and the magnetic steel groove 2 is J, the minimum distance between the third magnetic isolation hole 11 and the end of the first magnetic isolation hole 4 facing the axis hole 9 of the iron core body 1 is N, satisfying

[0094]

[0095] and / or

[0096]

[0097] By adjusting the distance and position between the second magnetic isolation hole 5 and the third magnetic isolation hole 11, the magnetic field line distribution near both ends of the magnetic pole is further sorted and optimized, reducing the back electromotive force harmonics and the iron loss of the motor.

[0098] Preferably, Figure 7 As shown, a V-shaped groove 12 is formed on the outer peripheral surface corresponding to the Q-axis of the iron core body. The two sides of the V-shaped groove 12 are respectively parallel to the magnetic steel grooves, which can further optimize the air-gap magnetic density waveform and reduce the harmonic content.

[0099] Preferably, Figure 8 As shown, each pole of the iron core body is provided with at least two first magnetic isolation holes 4.

[0100] Preferably, the permanent magnet 3 is any one of a rare earth permanent magnet 3, a ferrite permanent magnet 3, and a hybrid material permanent magnet 3. The iron core structure of this embodiment can be compatible with both concentrated winding motors and distributed winding motors.

[0101] Combined with the Figures 9 - 12 data shown, the iron core structure of this embodiment optimizes the electromagnetic force by 20% without reducing the output torque, reduces the torque ripple of the motor. The torque ripple at low frequency and light load drops from 33% to 21.4%, and at heavy load it can drop from 23.2% to 11.6%. It reduces the harmonic content in the air gap, reduces the iron loss of the motor by 25%, increases the motor efficiency by 1%, and reduces the compressor noise by 5 dB.

[0102] A rotor assembly adopts the above-mentioned iron core structure.

[0103] A motor adopts the above-mentioned iron core structure.

[0104] A compressor adopts the above-mentioned iron core structure.

[0105] It is easy for those skilled in the art to understand that, on the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0106] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention. The above is only the preferred implementation manner of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and modifications can still be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A core structure, characterized in that, Comprising: The iron core body; Multiple groups of magnetic steel grooves that are evenly distributed along the circumference of the iron core body and are used to accommodate permanent magnets; Multiple groups of first magnetic isolation holes respectively arranged between the magnetic steel grooves and the outer circumference of the iron core body. One end of the magnetic steel groove away from the D-axis is the first end. The first magnetic isolation hole is adjacent to the first end. The included angle between the magnetic steel groove and the D-axis is S, satisfying S = 10° - 90°; The first magnetic isolation hole is L-shaped, and one side of the L-shape is arranged along the radial direction of the iron core body; The first magnetic isolation hole includes a first hole part and a second hole part that form the L-shape. The first hole part is arranged along the radial direction of the iron core body. The second hole part is arranged at the end of the first hole part close to the axis hole of the iron core body, or the second hole part is arranged at the end of the first hole part away from the axis hole of the iron core body; The width of the first hole part along the circumferential direction of the iron core body is b1, the width of the second hole part along the circumferential direction of the iron core body is b2, the minimum distance from the first magnetic isolation hole to the D-axis is G, the minimum interval distance between the first magnetic isolation hole and the magnetic steel groove is J, the unilateral assembly clearance between the permanent magnet and the magnetic steel groove is g, the thickness of the permanent magnet is Hd, and the length of the permanent magnet is Ld, satisfying and / or, 2. The iron core structure according to claim 1, wherein, The iron core structure further includes multiple groups of second magnetic isolation holes. The second magnetic isolation holes are adjacent to the first magnetic isolation holes and are located on the side of the first magnetic isolation holes away from the D-axis.

3. The iron core structure according to claim 1, wherein The second hole part extends from the first hole part in the direction away from the D-axis, or the second hole part extends from the first hole part in the direction close to the D-axis.

4. The iron core structure according to claim 1, characterized in that, The included angle between the first hole part and the second hole part is R, satisfying R = 5° - 155°.

5. The iron core structure according to claim 1, wherein The height of the first hole part along the radial direction of the iron core body is a1, the height of the second hole part along the radial direction of the iron core body is a2, the included angle between the first hole part and the second hole part is R, the included angle between the magnetic steel groove and the D-axis is S, the thickness of the permanent magnet is Hd, and the length of the permanent magnet is Ld, satisfying 0 < a1 < 25×Ld×cosS×Hd×sinR; And / or 0 < (a1 - a2) < 25×Ld×cosS×Hd×sinR.

6. The iron core structure according to claim 1, wherein The side of the first magnetic isolation hole facing the D-axis is the first hole side. The included angle between the first hole side and the D-axis is T, satisfying T = 0° - 80°.

7. The iron core structure according to claim 5, wherein The minimum distance between the second magnetic isolation hole and the magnetic steel groove is c1, the minimum distance between the second magnetic isolation hole and the end of the first magnetic isolation hole facing the axis hole of the iron core body is c2, the minimum distance between the second magnetic isolation hole and the end of the first magnetic isolation hole facing the outer circumference of the iron core body is c3, the minimum interval distance between the first magnetic isolation hole and the magnetic steel groove is J, the minimum distance from the first magnetic isolation hole to the D-axis is G, the unilateral assembly clearance between the permanent magnet and the magnetic steel groove is g, the thickness of the permanent magnet is Hd, and the length of the permanent magnet is Ld, satisfying And / or And / or 8. The iron core structure according to claim 2, characterized in that, The second magnetic isolation hole is quadrilateral.

9. The iron core structure according to claim 8, wherein, The second magnetic isolation hole is a parallelogram, and the included angle between the side close to the D-axis and the outer circumference of the iron core body in the quadrilateral is an acute angle.

10. The iron core structure according to any one of claims 1-9, characterized in that, A third magnetic isolation hole is further provided at the first end of the magnetic steel groove.

11. The iron core structure according to claim 10, wherein One end of the third magnetic isolation hole communicates with the first end of the magnetic steel groove, and the other end faces the D axis. The included angle between the third magnetic isolation hole and the magnetic steel groove is Q.

12. The iron core structure according to claim 11, wherein, Q satisfies 5° ≤ Q ≤ 175°.

13. The iron core structure according to claim 11, characterized in that, When the iron core structure includes a second magnetic isolation hole, the distance between the third magnetic isolation hole and the second magnetic isolation hole is M. When the first magnetic isolation hole includes a first hole portion and a second hole portion forming an L shape, the width of the first hole portion along the circumferential direction of the iron core body is b1, the width of the second hole portion along the circumferential direction of the iron core body is b2, and the minimum distance between the first magnetic isolation hole and the magnetic steel groove is J. The minimum distance between the third magnetic isolation hole and the end of the first magnetic isolation hole facing the axis hole of the iron core body is N, and it satisfies and / or 14. The iron core structure according to any one of claims 1-9, 11-13, characterized in that, A V-shaped groove is provided on the outer peripheral surface of the iron core body corresponding to the Q axis, and both sides of the V-shaped groove are parallel to the magnetic steel groove.

15. The iron core structure according to any one of claims 1-9, 11-13, wherein at least two first magnetic isolation holes are provided at each pole of the iron core body.

16. The iron core structure according to claim 14, characterized in that, The permanent magnet is any one of a rare earth permanent magnet, a ferrite permanent magnet, and a hybrid material permanent magnet.

17. A rotor assembly, characterized in that, The iron core structure according to any one of claims 1-16 is adopted.

18. A motor, characterized in that, The iron core structure according to any one of claims 1-16 is adopted.

19. A compressor, characterized in that, The iron core structure according to any one of claims 1-16 is adopted.

Images