Motor rotors and permanent magnet motors

Abstract

The present invention provides a motor rotor and a permanent magnet motor. The motor rotor comprises a rotor core (1), the rotor core (1) is provided with a plurality of permanent magnet slots (2) along the circumferential direction, permanent magnets (3) are provided in the permanent magnet slots (2), magnetic isolation slots (4) are provided inside the permanent magnet slots (2), the width of the magnetic isolation slots (4) decreases along the radial direction close to the central axis of the rotor core (1), a first magnetic isolation hole in the shape of a strip is provided between two adjacent magnetic isolation slots (4), a magnetic isolation bridge is formed between the first magnetic isolation hole and the magnetic isolation slots (4), and a preset angle is formed between the magnetic isolation bridge and the center line of the magnetic pole. According to the motor rotor of the present invention, the magnetic isolation effect can be effectively improved, the magnetic leakage inside the motor rotor can be reduced, the magnetization saturation of the motor rotor can be improved, and the motor performance can be improved.

Description

Technical Field

[0001] The invention belongs to the technical field of motors, and in particular relates to a motor rotor and a permanent magnet motor. Background Art

[0002] The motor with permanent magnet tangential magnetization structure has the "magnetic concentration" effect and can produce higher air gap flux density than the permanent magnet radial magnetization motor, which makes the motor have a larger torque / current ratio and torque / volume ratio. It is increasingly used in servo systems, electric traction, office automation, household appliances and other occasions.

[0003] In the prior art tangential permanent magnet motor, since the rotor permanent magnets are arranged radially, a part of the permanent magnets is buried deep inside the rotor. When an external magnetic field is applied to the rotor, the magnetic conductive path inside the permanent magnet makes it difficult for the magnetizing magnetic field to enter the part of the rotor close to the shaft. The part of the permanent magnet close to the shaft cannot be magnetized to a saturated state, which can easily lead to a decrease in motor performance or even demagnetization of the permanent magnet, and the motor cannot operate. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to provide a motor rotor and a permanent magnet motor, which can effectively improve the magnetic isolation effect, reduce the magnetic leakage inside the motor rotor, increase the magnetization saturation of the motor rotor, and improve the motor performance.

[0005] In order to solve the above problems, the present invention provides a motor rotor, including a rotor core, wherein the rotor core is provided with a plurality of permanent magnet slots along the circumferential direction, permanent magnets are provided in the permanent magnet slots, magnetic isolation slots are provided on the inner side of the permanent magnet slots, the width of the magnetic isolation slots decreases along the radial direction close to the central axis of the rotor core, a first magnetic isolation hole in the shape of a strip is provided between two adjacent magnetic isolation slots, a magnetic isolation bridge is formed between the first magnetic isolation hole and the magnetic isolation slots, and a preset angle is formed between the magnetic isolation bridge and the center line of the magnetic pole.

[0006] Preferably, the preset angle between the magnetic isolation bridge and the center line of the magnetic pole is J, the angle between the center line of the magnetic pole and the center line of the permanent magnet is K, and the ratio of J / K satisfies the following relationship:

[0007] 2.2≥J / K≥1.5.

[0008] Preferably, a plurality of first magnetic isolation holes are respectively arranged on both sides of the center line of the magnetic pole, and a magnetic isolation bridge is formed between adjacent first magnetic isolation holes.

[0009] Preferably, the magnetic isolation groove is connected to the permanent magnet groove, a plurality of first magnetic isolation holes are opened outside the edge of the magnetic isolation groove, and the first magnetic isolation holes located on the same side of the magnetic pole center line are parallel to the edge of the magnetic isolation groove.

[0010] Preferably, the bottom of the first magnetic isolation hole has a sharp angle or a smoothly transitioned bottom angle toward the magnetic isolation groove on the side thereof, and the bottom angle is an acute angle.

[0011] Preferably, a first magnetic isolation bridge is formed between the first magnetic isolation hole and the magnetic isolation groove, the width of the first magnetic isolation hole is uniform, the width of the first magnetic isolation bridge is uniform, the width of the first magnetic isolation hole is B, the width of the first magnetic isolation bridge is A, and the ratio of B / A satisfies the following relationship:

[0012] 2≥B / A≥1.

[0013] Preferably, the first magnetic isolation hole includes a first strip hole and a second strip hole, the two first strip holes are symmetrical about the magnetic pole center line, the two second strip holes are symmetrical about the magnetic pole center line, and the first strip hole and the second strip hole are spaced apart.

[0014] Preferably, the first strip hole is located between the second strip hole and the magnetic isolation groove, a first magnetic isolation bridge is formed between the first strip hole and the magnetic isolation groove, and a second magnetic isolation bridge is formed between the second strip hole and the first strip hole.

[0015] Preferably, the two first strip-shaped holes are arranged at intervals, the two second strip-shaped holes are arranged at intervals, a third magnetic isolation bridge is formed between the two first strip-shaped holes, and a fourth magnetic isolation bridge is formed between the two second strip-shaped holes.

[0016] Preferably, the width of the third magnetic isolation bridge is the same as the width of the fourth magnetic isolation bridge.

[0017] Preferably, the two first strip-shaped holes are connected at the tip positions, and / or the two second strip-shaped holes are connected at the tip positions, and the first strip-shaped holes are not connected to the second strip-shaped holes.

[0018] Preferably, the two first strip-shaped holes are connected at the tip positions, and / or the two second strip-shaped holes are connected at the tip positions, and the first strip-shaped holes and the second strip-shaped holes are connected via the first connecting holes.

[0019] Preferably, the width of the first strip-shaped hole is B, the width of the first connecting hole is E, and the ratio of E / B satisfies the following relationship:

[0020] 2.5≥E / B≥1.

[0021] Preferably, the two second bar holes are connected at the tip position, and the two second bar holes are provided with a second connecting hole extending toward the central axis of the rotor core at the connecting position, and the bottom of the second connecting hole and the bottom of the first bar hole and the second bar hole are located on the same circumference centered on the central axis of the rotor core.

[0022] Preferably, the two second strip-shaped holes form a V-shaped groove, a second magnetic isolation hole is arranged in the V-shaped groove, the second magnetic isolation hole is spaced apart from the second strip-shaped hole, and a fifth magnetic isolation bridge is formed between the second magnetic isolation hole and the second strip-shaped hole.

[0023] Preferably, the width of the second magnetic isolation bridge is G, the width of the fifth magnetic isolation bridge is F, and the ratio of F / G should satisfy the following relationship:

[0024] 1.8≥F / G≥1.

[0025] Preferably, the two first strip holes are connected at the tip position, the two second strip holes are connected at the tip position, the first strip holes and the second strip holes are connected through the first connecting hole, and the second strip holes and the second magnetic isolation hole are connected through the second connecting hole.

[0026] Preferably, the two second strip holes form a V-shaped groove, a second magnetic isolation hole is arranged in the V-shaped groove, the second magnetic isolation hole is spaced apart from the second strip holes and is not connected, and a fifth magnetic isolation bridge is formed between the second magnetic isolation hole and the second strip holes.

[0027] Preferably, the first magnetic isolation hole includes two first strip holes and two second strip holes, the two first strip holes are respectively located on both sides of the center line of the magnetic pole, the two second strip holes are respectively located on both sides of the center line of the magnetic pole, and the two first strip holes are radially staggered along the rotor core; and / or the two second strip holes are radially staggered along the rotor core.

[0028] Preferably, the radial offset height of the two first strip holes and / or the two second strip holes is W, the side wall length of the first strip hole close to the center line of the magnetic pole is X, and the ratio of W / X should satisfy the following relationship:

[0029] 0.4 ≥ W / X ≥ 0.2.

[0030] Preferably, the first strip-shaped holes and the second strip-shaped holes have the same misalignment direction.

[0031] Preferably, the first magnetic isolation hole includes two first strip holes and two second strip holes, the two first strip holes are respectively located on both sides of the magnetic pole center line, the two second strip holes are respectively located on both sides of the magnetic pole center line, the angle between the first strip hole on the first side of the magnetic pole center line and the magnetic pole center line is U, and the angle between the first strip hole on the other side of the magnetic pole center line and the magnetic pole center line is V, where -1°≤UV≤1°.

[0032] Preferably, the width of the magnetic isolation bridge is gradually changed, wherein along the radial direction of the rotor core, the ratio between the outer width Y and the inner width Z of the magnetic isolation bridge satisfies:

[0033] 0.85≤Y / Z≤1.2.

[0034] Preferably, the first strip hole and / or the second strip hole on both sides of the center line of the magnetic pole have different widths on both sides, the width of the strip hole on the first side is I, and the width of the strip hole on the second side is H, when the ratio of I / H should satisfy the following relationship:

[0035] 1.2≥I / H≥0.9

[0036] Preferably, a non-magnetic fastening sheath is provided on the outer circumference of the rotor core.

[0037] Preferably, a non-magnetic reinforcing rod is arranged in the magnetic isolation groove and / or the magnetic isolation hole.

[0038] Preferably, the outer surface of the reinforcing rod is in contact with the inner surface of the magnetic isolation groove, or the shape of the reinforcing rod matches the shape of the magnetic isolation groove; and / or,

[0039] The outer surface of the reinforcing rod is in contact with the inner surface of the magnetic isolation hole, or the shape of the reinforcing rod matches the shape of the magnetic isolation hole.

[0040] Preferably, the magnetic isolation grooves and / or magnetic isolation holes are filled with non-magnetic conductive materials.

[0041] Preferably, a permanent magnet is provided in each permanent magnet slot, the permanent magnet is tangentially magnetized, and two adjacent permanent magnets are arranged with repelling polarities.

[0042] According to another aspect of the present invention, a permanent magnet motor is provided, comprising a motor rotor, which is the motor rotor described above.

[0043] The motor rotor provided by the present invention comprises a rotor core, wherein the rotor core is provided with a plurality of permanent magnet slots along the circumferential direction, wherein permanent magnets are provided in the permanent magnet slots, and a magnetic isolation slot is provided inside the permanent magnet slots, wherein the width of the magnetic isolation slot decreases along the radial direction close to the central axis of the rotor core, and a first magnetic isolation hole in the shape of a strip is provided between two adjacent magnetic isolation slots, and a magnetic isolation bridge is formed between the first magnetic isolation hole and the magnetic isolation slot, and a preset angle is formed between the magnetic isolation bridge and the center line of the magnetic pole. The first magnetic isolation hole in the shape of a strip cooperates with the magnetic isolation slot to form a magnetic isolation bridge with a preset angle between the center line of the magnetic pole, which can increase the magnetic resistance of the bottom passage of the permanent magnet slot, reduce the magnetic lines of force closed at this point by the magnetizing magnetic field, and promote the magnetic lines of force to enter the bottom position of the inner side of the permanent magnet, thereby improving the magnetizing saturation of the rotor permanent magnet, and at the same time, can reduce the leakage magnetic flux at the end of the permanent magnet close to the bottom of the rotor, thereby improving the no-load magnetic flux linkage of the motor, improving the output torque of the motor, and improving the efficiency of the motor, and at the same time, the more saturated the permanent magnet magnetization is, the stronger the anti-demagnetization ability of the motor is, and the working performance of the motor is effectively improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 A schematic diagram of the size structure of a motor rotor according to an embodiment of the present invention;

[0045] Figure 2 Schematic diagram of the magnetic circuit structure of the motor rotor according to an embodiment of the present invention;

[0046] Figure 3A schematic diagram of the size structure of a motor rotor according to another embodiment of the present invention;

[0047] Figure 4 A schematic diagram of the size structure of a motor rotor according to another embodiment of the present invention;

[0048] Figure 5 A schematic structural diagram of a motor rotor according to another embodiment of the present invention;

[0049] Figure 6 A schematic structural diagram of a motor rotor according to another embodiment of the present invention;

[0050] Figure 7 A schematic structural diagram of a motor rotor according to another embodiment of the present invention;

[0051] Figure 8 A schematic structural diagram of a motor rotor according to another embodiment of the present invention;

[0052] Fig. 9 A schematic diagram of the magnetic circuit structure of a motor rotor according to another embodiment of the present invention;

[0053] Fig.10 A schematic structural diagram of a motor rotor according to another embodiment of the present invention;

[0054] Fig.11 A schematic structural diagram of a motor rotor according to another embodiment of the present invention;

[0055] Fig.12 A schematic structural diagram of a motor rotor according to another embodiment of the present invention;

[0056] Fig.13 A schematic diagram of the size structure of a motor rotor according to another embodiment of the present invention;

[0057] Fig.14 A schematic diagram of the size structure of a motor rotor according to another embodiment of the present invention;

[0058] Fig.15 A schematic diagram of the size structure of a motor rotor according to another embodiment of the present invention;

[0059] Fig.16 Schematic diagram of the curve showing the relationship between the rotor flux of a motor and the change in J / K according to an embodiment of the present invention.

[0060] The reference numerals are as follows:

[0061] 1. Rotor core; 2. Permanent magnet slots; 3. Permanent magnets; 4. Magnetic isolation slots; 5. First magnetic isolation bridge; 6. First strip hole; 7. Second strip hole; 8. Second magnetic isolation bridge; 9. Third magnetic isolation bridge; 10. Fourth magnetic isolation bridge; 11. Fifth magnetic isolation bridge; 12. First connecting hole; 13. Second connecting hole; 14. Second magnetic isolation hole; 15. Fastening sleeve; 16. Reinforcing rod; 17. Rotating shaft hole; 18. Opening. DETAILED DESCRIPTION

[0062] See also Figures 1 to 16 As shown, according to an embodiment of the present invention, the motor rotor includes a rotor core 1, the rotor core 1 is provided with a plurality of permanent magnet slots 2 along the circumferential direction, permanent magnets 3 are provided in the permanent magnet slots 2, magnetic isolation slots 4 are provided on the inner side of the permanent magnet slots 2, the magnetic isolation slots 4 have a decreasing width along the radial direction close to the central axis of the rotor core 1, a first magnetic isolation hole in the shape of a strip is provided between two adjacent magnetic isolation slots 4, a magnetic isolation bridge is formed between the first magnetic isolation hole and the magnetic isolation slots 4, and a preset angle is formed between the magnetic isolation bridge and the center line of the magnetic pole.

[0063] The first strip-shaped magnetic isolation hole cooperates with the magnetic isolation slot 4 to form a magnetic isolation bridge with a preset angle with the center line of the magnetic pole, which can increase the magnetic resistance of the bottom path of the permanent magnet slot, reduce the magnetic lines of force of the magnetizing magnetic field closed here, and promote the magnetic lines of force to enter the bottom position of the inner side of the permanent magnet, thereby improving the magnetization saturation of the rotor permanent magnet. At the same time, it can reduce the leakage magnetic flux at the end of the permanent magnet near the bottom of the rotor, thereby improving the no-load magnetic flux linkage of the motor, increasing the output torque of the motor, and improving the efficiency of the motor. At the same time, the more saturated the permanent magnet is magnetized, the stronger the motor's anti-demagnetization ability is, which effectively improves the working performance of the motor.

[0064] In this embodiment, the permanent magnets 3 are uniformly distributed on the rotor core 1 along the circumferential direction, the number of permanent magnets 3 is N, where N is an even number greater than or equal to 4, each permanent magnet 3 is placed along the radial direction of the rotor core, and the permanent magnet 3 is magnetized along the tangential direction, and two adjacent permanent magnets 3 have the same polarity and are arranged relative to each other. A shaft hole 17 is provided on the inner side of the rotor core 1, the radial inner side of the permanent magnet slot 2 close to the shaft hole 17 is called the inner side of the permanent magnet slot 2, and the radial outer side close to the outer circle of the rotor is called the outer side of the permanent magnet slot 2, the rotor core 1 is an integrated structure, and a connecting rib is provided between the inner side of the permanent magnet slot and the shaft hole 17.

[0065] The side of the magnetic isolation groove 4 radially close to the shaft hole 17 is the top, the side radially away from the shaft hole 17 is the bottom, the side of the first magnetic isolation hole radially close to the shaft hole 17 is the bottom, and the side radially away from the shaft hole 17 is the top. That is, the radial inner side of the magnetic isolation groove 4 is the top side of the magnetic isolation groove 4, the radial outer side of the magnetic isolation groove 4 is the bottom side, the radial inner side of the first magnetic isolation hole is the bottom side, and the radial outer side of the first magnetic isolation hole is the top side.

[0066] An opening 18 is provided on the radially outer side of the permanent magnet slot 2 away from the shaft hole 17. The opening 18 penetrates the rotor core 1 radially outward from the permanent magnet slot 2, which can further reduce the leakage magnetic flux on the radially outer side of the permanent magnet 3, increase the air gap magnetic density, and improve the motor efficiency.

[0067] A magnetic isolation bridge is formed between the magnetic isolation slot 4 and the first magnetic isolation hole. When the tangential motor is magnetized, the rotor cores on both sides of the bottom of the permanent magnet slot 2 form a magnetic conduction path, and the magnetic lines of force are closed from this magnetic conduction path, making it difficult for the magnetic lines of force to enter the bottom inner position of the permanent magnet, forming a leakage magnetic flux Φσ. By arranging such a magnetic isolation structure at the bottom inner side of the permanent magnet, the magnetic resistance of the bottom path of the permanent magnet slot 2 can be increased, the magnetic lines of force closed at this point in the magnetizing magnetic field can be reduced, and the magnetic lines of force can be prompted to enter the bottom of the magnetic steel, thereby improving the magnetization saturation of the rotor permanent magnet 3. Even if a rigid shaft is used, the leakage magnetic flux at the end of the permanent magnet close to the inner side of the rotor can be reduced, thereby improving the magnetic flux linkage of the motor and improving the performance of the motor. At the same time, the outer side of the permanent magnet slot of the motor rotor is an open slot, which further reduces the leakage magnetic flux on the outer side of the permanent magnet, improves the air gap magnetic density, and improves the motor efficiency.

[0068] In this embodiment, a plurality of first magnetic isolation holes are respectively arranged on both sides of the center line of the magnetic pole, and a magnetic isolation bridge is formed between adjacent first magnetic isolation holes. The plurality of first magnetic isolation holes are stacked to form magnetic isolation bridges between each other. The plurality of magnetic isolation bridges can reduce the magnetic leakage inside the permanent magnet of the tangential permanent magnet motor, improve the magnetization saturation of the rotor permanent magnet, increase the magnetic flux of the motor, and improve the efficiency of the motor.

[0069] The magnetic isolation groove 4 is connected to the permanent magnet groove 2. A plurality of first magnetic isolation holes are provided on the outer side of the edge of the magnetic isolation groove 4. The first magnetic isolation holes on the same side of the magnetic pole center line are parallel to the edge of the magnetic isolation groove 4, thereby forming a magnetic isolation bridge with uniform width.

[0070] Preferably, the preset angle between the magnetic isolation bridge and the magnetic pole center line is J, the angle between the magnetic pole center line and the permanent magnet center line is K, and the ratio of J / K satisfies the following relationship: 2.2≥J / K≥1.5, such as Fig.16 If the angle between the magnetic isolation bridge and the center line of the magnetic pole is too large, the width of the magnetic isolation slot 4 in the radial direction of the rotor will become narrower, the area of ​​the magnetic isolation slot 4 will become smaller, the magnetic resistance of the magnetic isolation slot 4 will become smaller, and the magnetic resistance of the inner magnetic circuit of the permanent magnet will become smaller, which will in turn reduce the magnetization saturation of the permanent magnet and the motor flux. If the angle between the magnetic isolation bridge and the center line of the magnetic pole is too small, the length of the magnetic isolation bridge will be small, the magnetic isolation effect will be worse, and the motor flux will decrease. When set within this range, the magnetic isolation effect is better, the motor flux is higher, and the motor efficiency is better.

[0071] Preferably, the bottom of the first magnetic isolation hole has a sharp angle or a smoothly transitioned bottom angle toward the magnetic isolation groove 4 on the side thereof, and the bottom angle is an acute angle. The first magnetic isolation hole extends along the side edge of the magnetic isolation groove 4, and its bottom has a bottom angle close to the magnetic isolation groove 4, which can increase the length of the magnetic isolation bridge formed between the first magnetic isolation hole and the magnetic isolation groove 4, thereby improving the magnetic isolation effect.

[0072] Preferably, a first magnetic isolation bridge 5 is formed between the first magnetic isolation hole and the magnetic isolation slot 4, the width of the first magnetic isolation hole is uniform, the width of the first magnetic isolation bridge 5 is uniform, the width of the first magnetic isolation hole is B, the width of the first magnetic isolation bridge 5 is A, and the ratio of B / A satisfies the following relationship: 2≥B / A≥1. The narrower the width of the first magnetic isolation bridge 5, the greater the magnetic resistance of the magnetic circuit on the inner side of the rotor, the better the magnetic isolation effect, and the better the magnetic flux of the magnetizing magnetic field is limited to close along the bottom path of the permanent magnet slot, reduce leakage magnetism, increase the magnetic field strength inside the permanent magnet, increase the magnetization saturation of the permanent magnet, increase the magnetic flux of the motor, increase the utilization rate of the permanent magnet, and improve the cost performance of the motor.

[0073] In this embodiment, the first magnetic isolation hole includes a first strip hole 6 and a second strip hole 7. The two first strip holes 6 are symmetrical about the magnetic pole center line, and the two second strip holes 7 are symmetrical about the magnetic pole center line. The first strip holes 6 and the second strip holes 7 are spaced apart.

[0074] The first strip hole 6 is located between the second strip hole 7 and the magnetic isolation groove 4, a first magnetic isolation bridge 5 is formed between the first strip hole 6 and the magnetic isolation groove 4, and a second magnetic isolation bridge 8 is formed between the second strip hole 7 and the first strip hole 6. The widths of the first magnetic isolation bridge 5 and the second magnetic isolation bridge 8 can be the same or different, and can be specifically set as needed. Preferably, the width of the first magnetic isolation bridge 5 is the same as the width of the second magnetic isolation bridge 8.

[0075] Preferably, the two first strip holes 6 are arranged at intervals, the two second strip holes 7 are arranged at intervals, a third magnetic isolation bridge 9 is formed between the two first strip holes 6, and a fourth magnetic isolation bridge 10 is formed between the two second strip holes 7. In this embodiment, the third magnetic isolation bridge 9 and the fourth magnetic isolation bridge 10 both extend radially along the rotor core 1, and the third magnetic isolation bridge 9 and the fourth magnetic isolation bridge 10 are both arranged on the magnetic pole center line, the third magnetic isolation bridge 9 is symmetrical about the magnetic pole center line, and the fourth magnetic isolation bridge 10 is also symmetrical about the magnetic pole center line. Preferably, the width of the third magnetic isolation bridge 9 is C, and the width of the fourth magnetic isolation bridge 10 is D, C=D, so that the magnetization magnetic lines of force can be better restricted from passing through the third magnetic isolation bridge 9 and the fourth magnetic isolation bridge 10, improving the magnetic isolation effect, improving the magnetization saturation of the permanent magnet 3, improving the magnetic flux of the motor, improving the output power of the motor, and improving the efficiency of the motor. At the same time, the third magnetic isolation bridge 9 and the fourth magnetic isolation bridge 10 can serve as the connecting ribs between the rotor core 1 and the rotating shaft, improving the structural strength of the rotor, and improving the operating reliability of the motor.

[0076] Preferably, the two first strip holes 6 are connected at the tip position, and / or the two second strip holes 7 are connected at the tip position, and the first strip hole 6 and the second strip hole 7 are not connected. The strip holes are extended and connected at the radially outer position, which can increase the area of ​​the strip holes and increase the length of the magnetic isolation bridge. Together, they make the magnetic resistance of the magnetic circuit inside the rotor larger and improve the magnetic isolation effect. When the strip holes are connected, the closed path of the magnetic lines of force through the bottom of the permanent magnet is reduced, the leakage magnetic flux is reduced, the magnetic lines of force entering the bottom of the permanent magnet are increased, the magnetization saturation of the permanent magnet is increased, the induced magnetic flux of the permanent magnet in the stator winding is increased, the motor efficiency is improved, the reliability of the motor is guaranteed, and the cost consumption caused by the use of non-magnetic shafts can be reduced.

[0077] Preferably, the two first strip holes 6 are connected at the tip position, and / or the two second strip holes 7 are connected at the tip position, and the first strip hole 6 and the second strip hole 7 are connected through the first connecting hole 12. The first connecting hole 12 is, for example, a strip hole, and the width of the strip hole can be uniform or uneven, preferably the width of the strip hole is uniform. The first connecting hole 12 extends along the radial direction of the rotor core 1 and is symmetrical about the center line of the magnetic pole.

[0078] Preferably, the width of the first strip hole 6 is B, the width of the first connecting hole 12 is E, and the ratio of E / B satisfies the following relationship: 2.5≥E / B≥1. The first strip hole 6 and the second strip hole 7 are connected through the first connecting hole 12, which can reduce the third magnetic isolation bridge 9 and the fourth magnetic isolation bridge 10, reduce the leakage magnetic flux closed along this magnetic isolation bridge, further increase the magnetic isolation effect of the magnetic isolation structure, and improve the magnetization saturation of the permanent magnet. When using a motor with this rotor structure, when the motor is running, the leakage magnetic flux at the end of the permanent magnet near the bottom of the rotor can be reduced, the magnetic flux linkage can be increased, the torque can be increased, the output power of the motor can be increased, and the efficiency of the motor can be improved.

[0079] Preferably, the two second bar holes 7 are connected at the tip position, and the two second bar holes 7 are provided with a second connecting hole 13 extending toward the central axis of the rotor core 1 at the connecting position, and the bottom of the second connecting hole 13 and the bottom of the first bar hole 6 and the second bar hole 7 are located on the same circumference centered on the central axis of the rotor core 1. The second connecting hole 13 can increase the area of ​​the connecting hole, increase the magnetic resistance of the magnetic circuit inside the rotor, increase the comprehensive magnetic isolation effect of the magnetic isolation hole, and improve the magnetization saturation of the permanent magnet. Its bottom is on the same circumferential line as the bottom of the first bar hole 6 and the second bar hole 7, so that the minimum distances between the bar holes, the connecting holes and the shaft holes are equal on the circumference, ensuring the mechanical strength of the rotor.

[0080] Preferably, the two second strip holes 7 form a V-shaped groove, a second magnetic isolation hole 14 is arranged in the V-shaped groove, the second magnetic isolation hole 14 is spaced apart from the second strip hole 7, and a fifth magnetic isolation bridge 11 is formed between the second strip hole 7. In this embodiment, the second magnetic isolation hole 14 is in the shape of an isosceles triangle, which is symmetrical about the center line of the magnetic pole, and can increase the magnetic resistance of the bottom magnetic circuit, so that the magnetic circuit closed by the leakage flux is smaller.

[0081] The width of the second magnetic isolation bridge 8 is G, the width of the fifth magnetic isolation bridge 11 is F, and the ratio of F / G should satisfy the following relationship: 1.8≥F / G≥1. The fifth magnetic isolation bridge 11 is formed between the two side edges of the triangular hole and the strip holes on both sides, so that the magnetic isolation bridges are stacked and arranged, and the width of the fifth magnetic isolation bridge 11 is uniform at all locations. When the relationship between the second magnetic isolation bridge 8 and the fifth magnetic isolation bridge 11 satisfies the above constraints, the magnetic isolation effect can be further improved, the magnetization saturation of the permanent magnet can be improved, the utilization rate of the permanent magnet can be improved, the motor magnetic flux can be improved, the power density of the motor can be improved, the motor efficiency can be improved, and the motor performance can be improved.

[0082] In another embodiment, the two first strip holes 6 are connected at the tip position, the two second strip holes 7 are connected at the tip position, the first strip hole 6 and the second strip hole 7 are connected through the first connecting hole 12, and the second strip hole 7 and the second magnetic isolation hole 14 are connected through the second connecting hole 13. The second connecting hole 13 enables the first magnetic isolation hole to be connected with the second magnetic isolation hole 14, thereby further reducing the magnetic lines of force passing through the magnetic isolation bridge, increasing the area of ​​the connecting hole, increasing the magnetic resistance of the magnetic circuit inside the rotor, increasing the comprehensive magnetic isolation effect of the magnetic isolation hole, and improving the magnetization saturation of the permanent magnet.

[0083] Preferably, the two first strip holes 6 are connected at the tip position, and / or the two second strip holes 7 are connected at the tip position, the first strip holes 6 and the second strip holes 7 are not connected, the two second strip holes 7 form a V-shaped groove, a second magnetic isolation hole 14 is arranged in the V-shaped groove, the second magnetic isolation hole 14 is spaced from the second strip holes 7 and is not connected, and a fifth magnetic isolation bridge 11 is formed between the second magnetic isolation hole 14 and the second strip holes 7. In the present embodiment, the two first strip holes 6 form a V-shaped groove connected at the tip, the two second strip holes 7 form a V-shaped groove connected at the tip, the second magnetic isolation hole 14 is located in the V-shaped groove formed by the second strip holes 7, and the first strip holes 6, the second strip holes 7 and the second magnetic isolation holes 14 are not connected to each other, forming a magnetic isolation bridge that isolates each magnetic isolation hole, which can further enhance the structural strength of the rotor core 1 at the connection position with the rotating shaft.

[0084] Preferably, the first magnetic isolation hole includes two first bar holes 6 and two second bar holes 7, the two first bar holes 6 are respectively located on both sides of the center line of the magnetic pole, the two second bar holes 7 are respectively located on both sides of the center line of the magnetic pole, the two first bar holes 6 are radially staggered along the rotor core 1; and / or the two second bar holes 7 are radially staggered along the rotor core 1.

[0085] In this embodiment, the radial offset height of the two first strip holes 6 and / or the two second strip holes 7 is W, and the side wall length of the first strip hole along the center line of the magnetic pole is X. When the ratio of W / X should satisfy the following relationship: 0.4≥W / X≥0.2, setting the offset can reduce the width of the magnetic isolation bridge, increase the magnetic resistance of the inner magnetic circuit of the permanent magnet, and improve the magnetization saturation of the permanent magnet. However, the radial offset of the strip holes should not be too long. If it is too long, it will easily cause the width 5 of the first magnetic isolation bridge to be too narrow, thereby reducing the structural strength of the rotor.

[0086] Preferably, the offset directions of the first strip-shaped holes 6 and the second strip-shaped holes 7 are consistent.

[0087] The first magnetic isolation hole includes two first strip holes 6 and two second strip holes 7, the two first strip holes 6 are respectively located on both sides of the magnetic pole center line, the two second strip holes 7 are respectively located on both sides of the magnetic pole center line, the angle between the first strip hole 6 on the first side of the magnetic pole center line and the magnetic pole center line is U, the angle between the first strip hole 6 on the other side of the magnetic pole center line and the magnetic pole center line is V, wherein -1°≤UV≤1°, under the condition of ensuring the magnetization saturation, the precision requirements of the processing technology can be reduced, and the process cost of the motor can be reduced.

[0088] In another embodiment, the width of the magnetic isolation bridge is gradually changed, wherein the ratio between the outer width Y and the inner width Z of the magnetic isolation bridge along the radial direction of the rotor core 1 satisfies: 0.85≤Y / Z≤1.2. Under the condition of ensuring the magnetization saturation of the permanent magnet, the width of one side of the magnetic isolation bridge can be appropriately increased to increase the connection strength of the rotor magnetic isolation bridge.

[0089] In another embodiment, the first strip hole 6 and / or the second strip hole 7 on both sides of the center line of the magnetic pole have different widths on both sides, the width of the strip hole on the first side is I, and the width of the strip hole on the second side is H. When the ratio of I / H should satisfy the following relationship: 1.2≥I / H≥0.9, increasing the width of the strip hole, increasing the magnetic resistance of the strip hole, and increasing the magnetic resistance of the inner magnetic circuit of the permanent magnet can improve the magnetization saturation of the permanent magnet, making the widths on the left and right sides inconsistent, but increasing the width of the strip hole reduces the width of the magnetic isolation bridge and the strength of the rotor structure. Setting strip holes with inconsistent widths on the left and right sides can improve the magnetic isolation effect while ensuring strength and improve the magnetization saturation of the permanent magnet.

[0090] The outer peripheral side of the rotor core 1 is sleeved with a non-magnetic fastening sleeve 15. The fastening sleeve 15 is a sleeve structure, which is non-magnetic itself, and can further strengthen the motor rotor structure, improve the structural strength of the motor rotor, increase the operating frequency range of the motor rotor, improve the operating reliability, and broaden the application occasions of the tangential motor.

[0091] A non-magnetic reinforcing rod 16 is arranged in the magnetic isolation groove 4 and / or the magnetic isolation hole. The reinforcing rod 16 is non-magnetic. The surface of the reinforcing rod 16 placed on the inner side of the rotor is in contact with the magnetic isolation groove 4 or the magnetic isolation hole or matches the shape of the two. The part of the reinforcing rod 16 placed on the outer side of the rotor can be made into a circle or other shapes. The part of the reinforcing rod 16 placed on the outer side of the rotor is connected to the rotor baffle. On the one hand, the reinforcing rod 16 can increase the contact area of ​​the surface of the permanent magnet 3 while ensuring the magnetization saturation of the permanent magnet 3, reduce the local pressure during operation, better fix the permanent magnet 3, and prevent the risk of permanent magnet 3 breaking during operation. On the other hand, the reinforcing rod 16 is connected to the baffle of the rotor core 1, and cooperates with the baffle to further improve the structural strength of the motor rotor.

[0092] The magnetic isolation groove 4 and / or the magnetic isolation hole are filled with non-magnetic conductive material. The magnetic isolation groove 4 and the magnetic isolation hole can be completely filled with non-magnetic conductive material as a reinforcement, or non-magnetic conductive material can be filled after the reinforcing rod 16 is installed, so that the reinforcing rod 16 is fixed in the magnetic isolation groove 4 and / or the magnetic isolation hole by the filled non-magnetic conductive material.

[0093] The permanent magnet slot 2 may be rectangular or trapezoidal.

[0094] The above-mentioned magnetic isolation hole may be a first magnetic isolation hole and / or a second magnetic isolation hole.

[0095] According to an embodiment of the present invention, the permanent magnet motor includes a motor rotor, which is the motor rotor mentioned above.

[0096] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0097] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention. The above are only preferred embodiments of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present invention, and these improvements and variations should also be regarded as the protection scope of the present invention.

Claims

1. A motor rotor, characterized in that: The invention comprises a rotor core (1), wherein the rotor core (1) is provided with a plurality of permanent magnet slots (2) along the circumferential direction, wherein permanent magnets (3) are provided in the permanent magnet slots (2), and magnetic isolation slots (4) are provided on the inner sides of the permanent magnet slots (2), wherein the width of the magnetic isolation slots (4) decreases gradually along the radial direction close to the central axis of the rotor core (1), and a first magnetic isolation hole in the form of a strip is provided between two adjacent magnetic isolation slots (4), and a magnetic isolation bridge is formed between the first magnetic isolation hole and the magnetic isolation slots (4), and a preset angle is formed between the magnetic isolation bridge and the center line of the magnetic pole; The first magnetic isolation hole comprises a first strip-shaped hole (6) and a second strip-shaped hole (7), wherein: The two first strip holes (6) are symmetrical about the center line of the magnetic pole, the two second strip holes (7) are symmetrical about the center line of the magnetic pole, and the first strip hole (6) and the second strip hole (7) are arranged at intervals; the first strip hole (6) is located between the second strip hole (7) and the magnetic isolation groove (4), a first magnetic isolation bridge (5) is formed between the first strip hole (6) and the magnetic isolation groove (4), and a second magnetic isolation bridge (8) is formed between the second strip hole (7) and the first strip hole (6); Alternatively, the two first strip holes (6) are respectively located on both sides of the center line of the magnetic pole, the two second strip holes (7) are respectively located on both sides of the center line of the magnetic pole, and the two first strip holes (6) are staggered along the radial direction of the rotor core (1); and / or the two second strip holes (7) are staggered along the radial direction of the rotor core (1); Alternatively, the two first strip holes (6) are respectively located on both sides of the magnetic pole center line, the two second strip holes (7) are respectively located on both sides of the magnetic pole center line, the angle between the first strip hole (6) on the first side of the magnetic pole center line and the magnetic pole center line is U, and the angle between the first strip hole (6) on the other side of the magnetic pole center line and the magnetic pole center line is V, wherein -1°≤UV≤1°; Alternatively, the first strip hole (6) and / or the second strip hole (7) on both sides of the magnetic pole center line have different widths on both sides of the magnetic pole center line, the width of the strip hole on the first side is I, the width of the strip hole on the second side is H, and the ratio of I / H satisfies the following relationship: 1.2≥I / H≥0.

9.

2. The motor rotor according to claim 1, characterized in that: The preset angle between the magnetic isolation bridge and the center line of the magnetic pole is J, the angle between the center line of the magnetic pole and the center line of the permanent magnet is K, and the ratio of J / K satisfies the following relationship: 2.2≥J / K≥1.

5.

3. The motor rotor according to claim 1, characterized in that: A plurality of the first magnetic isolation holes are respectively arranged on both sides of the magnetic pole center line, and the magnetic isolation bridge is formed between adjacent first magnetic isolation holes.

4. The motor rotor according to claim 1, characterized in that: The magnetic isolation groove (4) is in communication with the permanent magnet groove (2), a plurality of the first magnetic isolation holes are provided on the outer side of the edge of the magnetic isolation groove (4), and the first magnetic isolation holes located on the same side of the magnetic pole center line are parallel to the edge of the magnetic isolation groove (4).

5. The motor rotor according to claim 1, characterized in that: A first magnetic isolation bridge (5) is formed between the first magnetic isolation hole and the magnetic isolation groove (4), and the magnetic isolation bridge comprises the first magnetic isolation bridge (5); the width of the first magnetic isolation hole is uniform, the width of the first magnetic isolation bridge (5) is uniform, the width of the first magnetic isolation hole is B, the width of the first magnetic isolation bridge (5) is A, and the ratio of B / A satisfies the following relationship: 2≥B / A≥1.

6. The motor rotor according to claim 1, characterized in that: When the two first strip holes (6) are symmetrical about the center line of the magnetic pole, the two second strip holes (7) are symmetrical about the center line of the magnetic pole, and the first strip holes (6) and the second strip holes (7) are arranged at intervals, the two first strip holes (6) are arranged at intervals, and the two second strip holes (7) are arranged at intervals, a third magnetic isolation bridge (9) is formed between the two first strip holes (6), and a fourth magnetic isolation bridge (10) is formed between the two second strip holes (7).

7. The motor rotor according to claim 6, characterized in that: The width of the third magnetic isolation bridge (9) is the same as the width of the fourth magnetic isolation bridge (10).

8. The motor rotor according to claim 1, characterized in that: When the two first strip holes (6) are symmetrical about the center line of the magnetic pole, the two second strip holes (7) are symmetrical about the center line of the magnetic pole, and the first strip holes (6) and the second strip holes (7) are arranged at intervals, the two first strip holes (6) are connected at the tip position, and / or the two second strip holes (7) are connected at the tip position, and the first strip holes (6) and the second strip holes (7) are not connected.

9. The motor rotor according to claim 1, characterized in that: When the two first strip holes (6) are symmetrical about the center line of the magnetic pole, the two second strip holes (7) are symmetrical about the center line of the magnetic pole, and the first strip holes (6) and the second strip holes (7) are arranged at intervals, the two first strip holes (6) are connected at the tip position, and / or the two second strip holes (7) are connected at the tip position, and the first strip holes (6) and the second strip holes (7) are connected through the first connecting hole (12).

10. The motor rotor according to claim 9, characterized in that: The width of the first strip-shaped hole (6) is B, the width of the first connecting hole (12) is E, and the ratio of E / B satisfies the following relationship: 2.5≥E / B≥1.

11. The motor rotor according to claim 1, characterized in that: When the two first strip holes (6) are symmetrical about the center line of the magnetic pole, the two second strip holes (7) are symmetrical about the center line of the magnetic pole, and the first strip holes (6) and the second strip holes (7) are arranged at intervals, the two second strip holes (7) are connected at the tip positions, and the two second strip holes (7) are provided with a second connecting hole (13) extending toward the center axis of the rotor core (1) at the connecting position, and the bottom of the second connecting hole (13) and the bottom of the first strip hole (6) and the second strip hole (7) are located on the same circumference centered on the center axis of the rotor core (1).

12. The motor rotor according to claim 1, characterized in that: When the two first strip holes (6) are symmetrical about the center line of the magnetic pole, and the two second strip holes (7) are symmetrical about the center line of the magnetic pole, and the first strip hole (6) and the second strip hole (7) are spaced apart; the first strip hole (6) is located between the second strip hole (7) and the magnetic isolation groove (4), a first magnetic isolation bridge (5) is formed between the first strip hole (6) and the magnetic isolation groove (4), and a second magnetic isolation bridge (8) is formed between the second strip hole (7) and the first strip hole (6), the two second strip holes (7) form a V-shaped groove, a second magnetic isolation hole (14) is provided in the V-shaped groove, the second magnetic isolation hole (14) is spaced apart from the second strip hole (7), and a fifth magnetic isolation bridge (11) is formed between the second strip hole (7) and the second strip hole (7).

13. The motor rotor according to claim 12, characterized in that: The width of the second magnetic isolation bridge (8) is G, the width of the fifth magnetic isolation bridge (11) is F, and the ratio of F / G should satisfy the following relationship: 1.8≥F / G≥1.

14. The motor rotor according to claim 12, characterized in that: The two first strip holes (6) are connected at the tip position, the two second strip holes (7) are connected at the tip position, the first strip holes (6) and the second strip holes (7) are connected via a first connecting hole (12), and the second strip holes (7) and the second magnetic isolation hole (14) are connected via a second connecting hole (13).

15. The motor rotor according to claim 8, characterized in that: The two second strip-shaped holes (7) form a V-shaped groove, a second magnetic isolation hole (14) is arranged in the V-shaped groove, the second magnetic isolation hole (14) and the second strip-shaped hole (7) are arranged at intervals and are not connected, and a fifth magnetic isolation bridge (11) is formed between the second magnetic isolation hole (14) and the second strip-shaped hole (7).

16. The motor rotor according to claim 1, characterized in that: When the two first strip holes (6) are respectively located on both sides of the center line of the magnetic pole, and the two second strip holes (7) are respectively located on both sides of the center line of the magnetic pole, the two first strip holes (6) are arranged in a radially offset manner along the rotor core (1); and / or when the two second strip holes (7) are arranged in a radially offset manner along the rotor core (1), the radial offset height of the two first strip holes (6) and / or the two second strip holes (7) is W, and the side wall length of the first strip hole (6) close to the center line of the magnetic pole is X, when the ratio of W / X satisfies the following relationship: 0.4≥W / X≥0.

2.

17. The motor rotor according to claim 16, characterized in that: The misalignment directions of the first strip-shaped holes (6) and the second strip-shaped holes (7) are consistent.

18. The motor rotor according to claim 1, characterized in that: The outer peripheral side of the rotor core (1) is sleeved with a non-magnetic fastening sleeve (15).

19. The motor rotor according to claim 1, characterized in that: A non-magnetic reinforcing rod (16) is arranged in the magnetic isolation groove (4) and / or the magnetic isolation hole.

20. The motor rotor according to claim 19, characterized in that: The outer surface of the reinforcing rod (16) contacts the inner surface of the magnetic isolation groove (4), or the shape of the reinforcing rod (16) matches the shape of the magnetic isolation groove (4); and / or, The outer surface of the reinforcing rod (16) contacts the inner surface of the magnetic isolation hole, or the shape of the reinforcing rod (16) matches the shape of the magnetic isolation hole.

21. The electric machine rotor according to any one of claims 1 to 20, characterized in that: The magnetic isolation groove (4) and / or the magnetic isolation hole are filled with non-magnetic conductive material.

22. The motor rotor according to claim 1, characterized in that: A permanent magnet (3) is arranged in each permanent magnet slot (2); the permanent magnet (3) is tangentially magnetized, and two adjacent permanent magnets (3) are arranged with polarities repelling each other.

23. A permanent magnet motor, comprising a motor rotor, characterized in that: The motor rotor is the motor rotor according to any one of claims 1 to 22.

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