CN114530954A - Motor rotor and self-starting synchronous reluctance motor - Google Patents

Abstract

The application provides a motor rotor and a self-starting synchronous reluctance motor. This electric motor rotor includes rotor core, rotor core is including the first iron core section that is located both ends and the second iron core section that is located the centre, first iron core section is formed by first iron core towards the piece superpose, the second iron core section is formed by second iron core towards the piece superpose, in the cross-section of the central axis of perpendicular to rotor core, first iron core towards the piece including the first D axle magnetic barrier groove that extends along the D axle direction, each first D axle magnetic barrier groove is including the first outer cast aluminium groove that is located both ends and the interior cast aluminium groove that is located the centre, the second iron core towards the piece including the second D axle magnetic barrier groove that extends along the D axle direction, each second D axle magnetic barrier groove is including the second outer cast aluminium groove that is located both ends, separate through the dull and stereotyped isolation layer between the second outer cast aluminium groove at both ends, the dull and stereotyped isolation layer corresponds the interior cast aluminium groove setting. According to the motor rotor, the eddy current passage can be cut off, and eddy current loss is effectively reduced.

Description

Motor rotor and self-starting synchronous reluctance motor

Technical Field

The application relates to the technical field of motors, in particular to a motor rotor and a self-starting synchronous reluctance motor.

Background

The direct-start synchronous reluctance motor combines the structural characteristics of an induction motor and a synchronous reluctance motor, realizes starting by generating torque through cage induction, realizes constant-speed operation by generating reluctance torque through the difference of rotor inductance, and can be directly connected with a power supply to realize starting operation. Compared with a direct-start permanent magnet motor, the direct-start synchronous reluctance motor has the advantages of no rare earth permanent magnet material, no demagnetization problem, low motor cost and good reliability. Compared with an asynchronous motor, the motor has high efficiency and constant rotating speed. The direct-start synchronous reluctance motor can be started automatically, a controller is not needed for starting, and the cost is further reduced.

The self-starting motor generates starting torque by cutting a stator magnetic field through a rotor conducting bar, and the rotor conducting bar is made of an electric and non-magnetic conducting material, usually pure aluminum, and is filled in a high-pressure casting mode. After the aluminum casting, end rings are formed at two ends of the rotor to short out all or part of the conducting bars. However, the longer bars generate eddy currents, which may heat the rotor and reduce the performance of the motor.

Disclosure of Invention

Therefore, the technical problem to be solved by the application is to provide a motor rotor and a self-starting synchronous reluctance motor, which can cut off an eddy current passage and effectively reduce eddy current loss.

In order to solve the problem, the application provides an electric motor rotor, including rotor core, rotor core is including the first iron core section that is located both ends and the second iron core section that is located the centre, first iron core section is formed by first iron core towards the superpose, the second iron core section is formed by second iron core towards the superpose, in the cross-section of the central axis of perpendicular to rotor core, first iron core towards the piece including the first D axle magnetic barrier groove that extends along the D axle direction, each first D axle magnetic barrier groove is including the first outer cast aluminium groove that is located both ends and the interior cast aluminium groove that is located the centre, the second iron core towards the piece including the second D axle magnetic barrier groove that extends along the D axle direction, each second D axle magnetic barrier groove is including the second outer cast aluminium groove that is located both ends, separate through dull and stereotyped isolation layer between the second outer cast aluminium groove at both ends, dull and stereotyped isolation layer corresponds the interior cast aluminium groove setting.

Preferably, the first outer cast aluminum groove and the second outer cast aluminum groove have the same structure and the same position.

Preferably, the first outer cast aluminium channel and the inner cast aluminium channel are spaced apart by an inner magnetic bridge.

Preferably, the rotor core is provided with a Q-axis magnetic barrier groove at the outermost side in the Q-axis direction.

Preferably, outer magnetic bridges are disposed on outer peripheral sides of the Q-axis magnetic barrier groove, the first D-axis magnetic barrier groove, and the second D-axis magnetic barrier groove.

Preferably, the rotor core comprises two first core segments and one second core segment, the axial height of the second core segment is L2, the thickness of the single second core stamped sheet is delta, and delta is less than or equal to L2.

Preferably, the rotor core comprises three first core segments and two second core segments, wherein the axial height of the two first core segments at two ends is L1, the axial height of the first core segment between the two second core segments is L3, the axial height of each second core segment is L2, the axial height of the rotor core is L, L1 is more than or equal to 1/3L, L2 is more than L3 and is less than or equal to 1/3L, and L2 is more than 0.

Preferably, the first outer cast aluminum groove, the inner cast aluminum groove and the second outer cast aluminum groove are filled with conductive non-magnetic materials to form conducting bars, end rings are formed at two ends of the rotor core, and the end rings are connected with the conducting bars to form short circuit rings.

Preferably, the end ring is annular, the inner diameter of the end ring is larger than or equal to the diameter of the shaft hole of the rotor core, and the outer diameter of the end ring is smaller than or equal to the diameter of the outer circle of the rotor core.

According to another aspect of the present application, there is provided a self-starting synchronous reluctance motor comprising a motor rotor as described above.

The application provides an electric motor rotor, including rotor core, rotor core is including the first iron core section that is located both ends and the second iron core section that is located the centre, first iron core section is formed by first iron core towards the piece superpose, the second iron core section is formed by second iron core towards the piece superpose, in the cross-section of the central axis of perpendicular to rotor core, first iron core towards the piece including the first D axle magnetic barrier groove that extends along the D axle direction, each first D axle magnetic barrier groove is including the first outer cast aluminium groove that is located both ends and the interior cast aluminium groove that is located the centre, the second iron core towards the piece including the second D axle magnetic barrier groove that extends along the D axle direction, each second D axle magnetic barrier groove is including the outer cast aluminium groove of the second that is located both ends, separate through dull and stereotyped isolation layer between the outer cast aluminium groove of second at both ends, dull and stereotyped isolation layer corresponds the interior cast aluminium groove setting. This rotor core adopts two kinds of rotor punching combinations to form, can be through cast aluminium trench position for the second iron core section that the second iron core punching of flat isolation layer formed cut off the conducting bar of the first iron core section of cast aluminium in the cast aluminium trench to improve the vortex problem that the conducting bar overlength leads to, effectively cut off the vortex passageway, with its segmentation, weaken or eliminate the vortex, reduce the rotor and generate heat, and then improve motor performance.

Drawings

FIG. 1 is a schematic structural diagram of a rotor of an electric machine according to an embodiment of the present application;

FIG. 2 is a schematic structural diagram of a rotor of an electric machine according to an embodiment of the present application;

fig. 3 is a schematic structural view of a first rotor punching of a motor rotor according to an embodiment of the present application;

fig. 4 is a schematic structural view of a second rotor punching of the motor rotor according to an embodiment of the present application;

FIG. 5 is a schematic structural diagram of a rotor of an electric machine according to an embodiment of the present application;

FIG. 6 is a graph of thickness versus performance for a second core segment of a rotor of an electric machine according to one embodiment of the present application;

fig. 7 is a graph comparing efficiency of a rotor of an electric machine according to an embodiment of the present application with a rotor of an electric machine of the related art.

The reference numerals are represented as:

1. a first core segment; 2. a second core segment; 3. a first iron core punching sheet; 4. a second iron core punching sheet; 5. a first D-axis magnetic barrier groove; 6. a second D-axis magnetic barrier groove; 7. a first outer cast aluminum trough; 8. internally casting an aluminum groove; 9. a second outer cast aluminum groove; 10. a plate isolation layer; 11. an inner magnetic bridge; 12. an outer magnetic bridge; 13. a Q-axis magnetic barrier groove; 14. conducting bars; 15. and an end ring.

Detailed Description

Referring to fig. 1 to 7 in combination, according to the embodiment of the present application, the rotor of the electric machine includes a rotor core, the rotor core includes first core segments 1 located at two ends and a second core segment 2 located in the middle, the first core segments 1 are formed by stacking first core stamped sheets 3, the second core segments 2 are formed by stacking second core stamped sheets 4, in the cross-section of the central axis of perpendicular to rotor core, first iron core punching sheet 3 includes along the first D axle magnetic barrier groove 5 that the D axle direction extends, each first D axle magnetic barrier groove 5 is including the first outer cast aluminium groove 7 that is located both ends and the interior cast aluminium groove 8 that is located the centre, second iron core punching sheet 4 is including the second D axle magnetic barrier groove 6 that extends along the D axle direction, each second D axle magnetic barrier groove 6 is including the outer cast aluminium groove 9 of the second that is located both ends, separate through dull and stereotyped isolation layer 10 between the outer cast aluminium groove 9 of second at both ends, dull and stereotyped isolation layer 10 corresponds interior cast aluminium groove 8 setting.

This rotor core adopts two kinds of rotor punching combinations to form, can be through cast aluminium groove position in the interior for the second iron core section 2 that second iron core punching 4 of flat isolation layer 10 formed cut off the conducting bar 14 of cast aluminium 8 cast aluminium's first iron core section 1 to improve the vortex problem that the conducting bar 14 overlength leads to, effectively cut off the vortex passageway, with its segmentation, weaken or eliminate the vortex, reduce the rotor and generate heat, and then improve motor performance.

In one embodiment, the first outer cast aluminum groove 7 and the second outer cast aluminum groove 9 are identical in structure and position.

In this embodiment, the motor rotor includes a first iron core stamped sheet 3 and a second iron core stamped sheet 4 having a special structure, where a plurality of groups of magnetic barrier grooves are formed on the first iron core stamped sheet 3, the number of groups of magnetic barrier grooves is the number of poles of the rotor, and according to the shape of the magnetic barrier grooves, a radial direction parallel to the magnetic barrier grooves is a D axis, and a radial direction perpendicular to the magnetic barrier grooves is a Q axis. The cast aluminum grooves of the first iron core stamped steel 3 are divided into two layers according to the inner and outer directions, namely a first outer cast aluminum groove 7 and an inner cast aluminum groove 8, and a magnetic conduction channel is formed between the adjacent first D-axis magnetic barrier grooves 5. The first iron core towards piece 3 with the difference of second iron core towards piece 4 just lie in having or not cast aluminium groove 8 in, second iron core towards piece 4 compares and offers a plurality of cast aluminium grooves in first iron core towards piece 3 the same, and cast aluminium groove outside both is unanimous, but the cast aluminium groove position in the second iron core towards piece 4 is replaced by dull and stereotyped isolation layer 10 for the cast aluminium groove position in on the second iron core towards piece 4 is sealed, and the thickness of dull and stereotyped isolation layer 10 is unanimous with the axial thickness of second iron core towards piece 4. In one embodiment, the number of rotor pole pairs P is 2.

In one embodiment, the first outer cast aluminum tank 7 and the inner cast aluminum tank 8 are spaced apart by an inner magnetic bridge 11. The first outer aluminum casting groove 7 and the inner aluminum casting groove 8 are separated by the inner magnetic bridge 11, the structural strength of the rotor is increased, the aluminum casting process is to inject aluminum liquid into the rotor groove through high temperature and high pressure, if the structural strength of the rotor is insufficient, the rotor structure is easily damaged in the aluminum casting process, the rotor structure is deformed and even scrapped, and the inner magnetic bridge 11 can effectively avoid the phenomenon.

In one embodiment, the rotor core is provided with a Q-axis barrier groove 13 at the outermost side in the Q-axis direction. The width of the Q-axis magnetic barrier groove 13 should be as wide as possible, so that the amount of aluminum cast in the Q-axis magnetic barrier groove 13 can be ensured, and the starting capability of the motor rotor can be improved.

In one embodiment, the outer circumferential sides of the Q-axis barrier groove 13, the first D-axis barrier groove 5, and the second D-axis barrier groove 6 are provided with the outer bridges 12, and the structural strength of the motor can be improved using the outer bridges 12.

In this embodiment, the motor rotor has no magnetism, and is produced by high-temperature and high-pressure die casting in a full aluminum casting manner, and all magnetic barrier grooves on the rotor are filled with aluminum liquid in a stamping manner to form the conducting bars 14. Rotor core is folded by the cooperation of first iron core towards piece 3 and 4 axial of second iron core towards piece and is pressed and constitute to make the conducting bar can be cut off by dull and stereotyped isolation layer 10 on the second iron core towards piece 4, play the effect that reduces the eddy current loss. The cast aluminum groove may be filled with other conductive and non-conductive materials, such as red copper, instead of aluminum.

In one embodiment, the rotor core comprises two first core segments 1 and one second core segment 2, the axial height of the second core segment 2 is L2, the thickness of the single second core stamped steel 4 is δ, and δ is equal to or less than L2. In this embodiment, the second core segment 2 formed by the second core segment 4 is located between the two first core segments 1 for isolating the connection of the conducting bars 14 in the inner cast aluminum slot 8.

In one embodiment, the rotor core comprises three first core segments 1 and two second core segments 2, wherein the axial height of the two first core segments 1 at two ends is L1, the axial height of the first core segment 1 between the two second core segments 2 is L3, the axial height of each second core segment 2 is L2, the axial height of the rotor core is L, L1 is more than or equal to 1/3L, and L2 is more than or equal to L3 and less than or equal to 1/3L.

The second iron core punching sheet 4 is superposed in the middle of the rotor iron core and has the effect of cutting off the conducting bars 14 in the cast aluminum grooves 8 in the fully cast aluminum rotor iron core, so that the length of the conductors in the magnetic barrier grooves is reduced, the eddy current loss is avoided, and the overall efficiency of the motor is further improved. However, the thickness L2 of the second core segment 4 cannot be too large, and too large generates eddy current and causes loss. As can be seen from the comparison between the thickness of the second core segment 4 and the performance of the motor shown in fig. 6, as the thickness L2 of the second core segment 4 increases, the efficiency of the motor increases and then decreases, and therefore, an appropriate thickness L2 is determined. As can be seen from the figure, when the number of the second iron core punching sheets is between 3 and 5, the efficiency is high, and when the number is 4, the efficiency is highest. In one embodiment, the thickness of the single second core segment 4 is 1 mm.

The electric motor rotor of this application embodiment, because the outer cast aluminium groove of D axle cast aluminium groove runs through whole rotor core's axial, consequently outer cast aluminium groove is great, and the starting ability is strong to can utilize 2 structures in second iron core section to reduce eddy current loss, consequently the efficiency of the motor improves about three percent than prior art scheme. The D-axis aluminum casting groove comprises a first outer aluminum casting groove 7, an inner aluminum casting groove 8 and a second outer aluminum casting groove 9.

In one embodiment, the first outer cast aluminum groove 7, the inner cast aluminum groove 8 and the second outer cast aluminum groove 9 are filled with conductive and non-conductive material to form the conducting bars 14, end rings 15 are formed at two ends of the rotor core, and the end rings 15 are connected with the conducting bars 14 to form short circuit rings.

In one embodiment, the end ring 15 is annular, the inner diameter of the end ring 15 is greater than or equal to the diameter of the shaft hole of the rotor core, and the outer diameter of the end ring 15 is less than or equal to the diameter of the outer circle of the rotor core.

In this embodiment, the rotor core has large aluminum end rings 15 at both ends, the outer diameter of the end rings is slightly smaller than or equal to the outer diameter of the rotor core, and the inner diameter of the end rings 15 is slightly larger than or equal to the shaft hole diameter of the rotor core, so that the end rings 15 can form a solid structure. Because all the magnetic barrier grooves are of cast aluminum structures, tools are not needed to support air grooves, and larger end rings can be designed as far as possible, so that the two ends of the rotor can form larger truncated cone-shaped end rings to ensure sufficient cast aluminum quantity, and the end rings 15 at the two ends are connected through the conducting bars 14 in the magnetic barrier grooves to form a passage, so that the starting performance of the motor is ensured.

In one embodiment, the pole pair number P of the motor rotor is 2, the rotor is strong in structural performance, the motor rotor is manufactured and produced through a full aluminum casting process, the position of an aluminum casting tool does not need to be considered in the production process, the aluminum casting is convenient to implement, and the manufacturing cost and the difficulty are reduced.

According to an embodiment of the application, the self-starting synchronous reluctance motor comprises a motor rotor which is the motor rotor.

It is readily understood by a person skilled in the art that the advantageous ways described above can be freely combined, superimposed without conflict.

The present invention is not intended to be limited to the particular embodiments shown and described, but is to be accorded the widest scope consistent with the principles and novel features herein disclosed. The foregoing is only a preferred embodiment of the present application, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present application, and these modifications and variations should also be considered as the protection scope of the present application.

Claims (10)

1. A motor rotor is characterized by comprising a rotor core, wherein the rotor core comprises first core segments (1) located at two ends and a second core segment (2) located in the middle, the first core segments (1) are formed by overlapping first core stamped sheets (3), the second core segments (2) are formed by overlapping second core stamped sheets (4), in a cross section perpendicular to the central axis of the rotor core, the first core stamped sheets (3) comprise first D-axis magnetic barrier grooves (5) extending along the D-axis direction, each first D-axis magnetic barrier groove (5) comprises first outer cast aluminum grooves (7) located at two ends and an inner cast aluminum groove (8) located in the middle, the second core stamped sheets (4) comprise second D-axis magnetic barrier grooves (6) extending along the D-axis direction, each second outer cast aluminum groove (6) comprises second cast aluminum grooves (9) located at two ends, the second outer cast aluminum grooves (9) at the two ends are separated by flat plate isolation layers (10), and the flat plate isolation layers (10) are arranged corresponding to the inner cast aluminum grooves (8).

2. The machine rotor according to claim 1, characterised in that the first outer cast aluminium groove (7) and the second outer cast aluminium groove (9) are identical in structure and position.

3. An electric machine rotor according to claim 1, characterised in that the first outer cast aluminium slot (7) and the inner cast aluminium slot (8) are spaced apart by an inner magnetic bridge (11).

4. The electric machine rotor according to claim 1, characterized in that the rotor core is provided with a Q-axis barrier groove (13) at the outermost side in the Q-axis direction.

5. The electric machine rotor as recited in claim 4, characterized in that outer peripheral sides of the Q-axis barrier groove (13), the first D-axis barrier groove (5), and the second D-axis barrier groove (6) are provided with outer magnetic bridges (12).

6. The electric machine rotor according to claim 1, characterized in that the rotor core comprises two first core segments (1) and one second core segment (2), the second core segment (2) has an axial height of L2, the thickness of the single second core sheet (4) is δ, δ ≦ L2.

7. The electric machine rotor according to claim 1, characterized in that the rotor core comprises three first core segments (1) and two second core segments (2), wherein the axial height of the two first core segments (1) at both ends is L1, the axial height of the first core segment (1) between the two second core segments (2) is L3, the axial height of each second core segment (2) is L2, the axial height of the rotor core is L, L1 ≧ 1/3L, L2 < L3 ≦ 1/3L, and L2 > 0.

8. An electric machine rotor according to claim 1, characterized in that the first outer cast aluminium slot (7), the inner cast aluminium slot (8) and the second outer cast aluminium slot (9) are filled with an electrically and magnetically non-conductive material to form bars (14), and that end rings (15) are formed at both ends of the rotor core, and the end rings (15) are connected with the bars (14) to form short-circuit rings.

9. An electric machine rotor according to claim 8, characterized in that the end ring (15) is annular, the inner diameter of the end ring (15) being larger than or equal to the shaft hole diameter of the rotor core, and the outer diameter of the end ring (15) being smaller than or equal to the outer circle diameter of the rotor core.

10. A self-starting synchronous reluctance machine comprising a machine rotor, characterized in that said machine rotor is a machine rotor according to any one of claims 1 to 9.

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