Motor rotor and self-starting synchronous reluctance motor

Abstract

The present application provides a motor rotor and a self-starting synchronous reluctance motor. The motor rotor comprises a rotor core (1), the rotor core (1) is provided with a filling slot and a slit slot (2), the filling slot comprises a d-axis filling slot (3) provided between the d-axis and the q-axis and close to the d-axis, and end rings (7) are provided at both ends of the rotor core (1), the end rings (7) cover the area where the d-axis filling slot (3) is located, and avoid the area where the slit slot (2) is located. According to the motor rotor of the present application, the problem of small flow hole area on the rotor and poor heat dissipation performance of the motor can be effectively solved.

Description

Technical Field

[0001] The present application relates to the technical field of motors, and in particular to a motor rotor and a self-starting synchronous reluctance motor. Background Art

[0002] The self-starting synchronous reluctance motor combines the advantages of the asynchronous motor on the basis of the synchronous reluctance motor. It realizes self-starting through the asynchronous torque generated by the rotor bars, and does not require inverter drive. Compared with the asynchronous motor, the motor can achieve constant speed operation, low rotor loss, and improved efficiency during synchronous operation; compared with the asynchronous starting permanent magnet synchronous motor, the motor does not use permanent magnet materials, has low cost, and does not have the risk of permanent magnet demagnetization. However, in the two-stage self-starting synchronous reluctance motor, there is usually a problem that the flow hole area on the rotor is not large enough and the motor heat dissipation performance is poor. Summary of the invention

[0003] Therefore, the technical problem to be solved by the present application is to provide a motor rotor and a self-starting synchronous reluctance motor, which can effectively solve the problems of small flow hole area on the rotor and poor heat dissipation performance of the motor.

[0004] In order to solve the above problems, the present application provides a motor rotor, including a rotor core, on which filling grooves and slit slots are arranged, the filling grooves including a d-axis filling groove arranged between the d-axis and the q-axis close to the d-axis, and end rings are arranged at both ends of the rotor core, the end rings cover the area where the d-axis filling groove is located and avoid the area where the slit slot is located.

[0005] Preferably, along the q-axis direction, the slit groove is located outside the d-axis filling groove.

[0006] Preferably, the d-axis filling grooves are disposed on both sides of the d-axis and are symmetrical about the q-axis.

[0007] Preferably, between the rotor shaft hole on one side of the q-axis and the rotor outer circle, the d-axis filling grooves are arranged in n layers along the d-axis direction, and m d-axis filling grooves are placed in each layer, where n≥2 and m≥2.

[0008] Preferably, the d-axis filling groove is in the shape of an elongated strip.

[0009] Preferably, along the direction away from the rotor shaft hole, the width of the d-axis filling groove in the q-axis direction increases gradually.

[0010] Preferably, a q-axis filling slot is also provided on the rotor core, the q-axis filling slot is located on the q-axis, and the slit slots are located on both sides of the q-axis filling slot; and / or, a q-axis filling slot is also provided on the rotor core, the q-axis filling slot is located on the q-axis, and the q-axis filling slot is located between the outermost slit slot along the q-axis direction and the outer circle of the rotor.

[0011] Preferably, the slit grooves are located on both sides of the q-axis filling grooves, and when the q-axis filling grooves and the corresponding slit grooves are arranged in the same layer, dividing ribs are arranged between the slit grooves and the q-axis filling grooves in the same layer.

[0012] Preferably, the width of the dividing rib along the d-axis direction is t, 0.5*σ≤t≤1.5σ, wherein σ is the width of the air gap between the stator and the rotor.

[0013] Preferably, when the q-axis filling groove is located between the outermost slit groove and the outer circle of the rotor along the q-axis direction, at least one layer of q-axis filling groove is arranged between the outermost slit groove and the outer circle of the rotor, and the q-axis filling groove is circular, elliptical or rectangular.

[0014] Preferably, the slit groove is U-shaped or straight-line shaped, and the slit groove includes straight line segments and / or arc segments.

[0015] Preferably, all the filling slots are filled with conductive and non-magnetic materials and are short-circuited and connected via end rings to form a squirrel cage structure.

[0016] Preferably, the total area of ​​the slit grooves not covered by the end rings accounts for 50% to 80% of the total area of ​​the filling grooves and the slit grooves.

[0017] Preferably, the rotor shaft hole is circular, elliptical or polygonal.

[0018] Preferably, the slit grooves located in the same layer are of a whole groove structure.

[0019] According to another aspect of the present application, a self-starting synchronous reluctance motor is provided, comprising a motor rotor, which is the motor rotor described above.

[0020] The motor rotor provided by the present application includes a rotor core, and a filling slot and a slit slot are arranged on the rotor core, wherein the filling slot includes a d-axis filling slot arranged between the d-axis and the q-axis and close to the d-axis, and end rings are arranged at both ends of the rotor core, and the end rings cover the area where the filling slot is located and avoid the area where the slit slot is located. The end rings of the motor rotor only cover the filling slot position and avoid the slit slot, while ensuring the effectiveness of the squirrel cage structure, the slit slot area is reserved for use as a circulation hole, so that the rotor space can be fully utilized, and the area of ​​the rotor circulation hole is greatly increased, so as to form effective heat dissipation for the motor rotor. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a structural schematic diagram of a motor rotor without end rings according to an embodiment of the present application;

[0022] Figure 2 This is a schematic diagram of the structure of a motor rotor according to an embodiment of the present application;

[0023] Figure 3This is a structural schematic diagram of a motor rotor without end rings according to an embodiment of the present application;

[0024] Figure 4 This is a schematic diagram of the structure of a motor rotor according to an embodiment of the present application.

[0025] The reference numerals are:

[0026] 1. Rotor core; 2. Slit slot; 3. D-axis filling slot; 4. Q-axis filling slot; 5. Splitting rib; 6. Rotor shaft hole; 7. End ring. DETAILED DESCRIPTION

[0027] See also Figures 1 to 4 As shown, according to an embodiment of the present application, the motor rotor includes a rotor core 1, on which a filling groove and a slit groove 2 are arranged, the filling groove includes a d-axis filling groove 3 arranged between the d-axis and the q-axis close to the d-axis, and end rings 7 are arranged at both ends of the rotor core 1, the end rings 7 cover the area where the d-axis filling groove 3 is located and avoid the area where the slit groove 2 is located.

[0028] The end ring 7 of the motor rotor only covers the filling slot position and avoids the slit slot 2. While ensuring the effectiveness of the squirrel cage structure, the area where the slit slot 2 is located is reserved for use as a flow hole, so that the rotor space can be fully utilized. At the same time, the area of ​​the rotor flow hole is maximized to effectively dissipate heat for the motor rotor.

[0029] In one embodiment, along the q-axis direction, the slit slot 2 is located outside the d-axis filling slot 3. In this embodiment, the d-axis filling slot 3 is arranged on both sides of the d-axis, and the slit slot 2 is arranged on the side of the d-axis filling slot 3 away from the d-axis, which can reduce the space competition problem between the filling slot and the slit slot 2 on the rotor core 1, and achieve the purpose of improving the rotor space utilization rate, and can fully utilize the d-axis space position on both sides of the rotor. At the same time, the slit slot 2 is arranged in the area of ​​the rotor q-axis direction, so that the filling slot leaves the position of the two ends of the slit slot 2 close to the outer circle of the rotor, so that the slit slot 2 can extend to the outer circle of the rotor, thereby increasing the arrangement space of the slit slot 2 and improving the salient pole ratio of the motor rotor.

[0030] Since the d-axis filling slots on both sides of the q-axis are the solid structure of the rotor core 1 and no slit slots 2 are provided, there is enough space between the d-axis and the slit slots, and enough d-axis filling slots are provided to ensure the starting capability of the motor.

[0031] In one embodiment, the d-axis filling grooves 3 are disposed on both sides of the d-axis and are symmetrical about the q-axis.

[0032] In one embodiment, between the rotor shaft hole 6 on one side of the q-axis and the outer circle of the rotor, the d-axis filling slots 3 are arranged in n layers along the d-axis direction, and m d-axis filling slots 3 are placed in each layer, n≥2, m≥2, that is, the number of d-axis filling slots 3 located on both sides of the rotor is 2mn≥8; such a design is used to fully utilize the space in the d-axis direction of the rotor, while maximizing the number of filling slots and increasing the cast aluminum amount of the rotor, thereby ensuring that the motor has a certain load starting capability.

[0033] In one embodiment, the d-axis filling slot 3 is in the shape of a long strip. The shape of each d-axis filling slot is not limited to a rectangular structure or a circular structure composed of straight lines or arcs, and preferably a rectangular structure is selected; since the d-axis filling slot 3 is only arranged at the d-axis positions on both sides of the rotor, the arrangement space is small, and it is selected to be designed as a rectangular structure, which can improve the utilization rate of the space.

[0034] In one embodiment, the width of the d-axis filling slot 3 in the q-axis direction increases gradually along the direction away from the rotor shaft hole 6. In this embodiment, the end of the slit slot 2 away from the q-axis is bent in the direction away from the d-axis, so that there is more space available in this area. Therefore, in the direction away from the rotor shaft hole, the d-axis filling slot 3 is set to have a width increasing in the q-axis direction, which can make fuller use of the space at this position, increase the filling slot area, and improve the motor self-starting ability.

[0035] In one embodiment, a q-axis filling slot 4 is also provided on the rotor core 1, the q-axis filling slot 4 is located on the q-axis, and the slit slot 2 is located on both sides of the q-axis filling slot 4. A q-axis filling slot 4 is also provided on the rotor core 1, the q-axis filling slot 4 is located on the q-axis, and the q-axis filling slot 4 is located between the outermost slit slot 2 along the q-axis direction and the outer circle of the rotor.

[0036] In this embodiment, the q-axis filling groove 4 disposed in the same layer as the slit groove 2 is a non-independent filling groove, and the q-axis filling groove 4 located outside the slit groove 2 is an independent filling groove.

[0037] The slit slot 2 is located on both sides of the q-axis filling slot 4, and when the q-axis filling slot 4 and the corresponding slit slot 2 are arranged in the same layer, a dividing rib 5 is arranged between the slit slot 2 and the q-axis filling slot 4 in the same layer. The dividing rib 5 is designed here to design the q-axis filling slot 4 as an independent individual, prevent the conductive and non-magnetic conductive material from penetrating into the slit slot 2, and also strengthen the rotor structure strength.

[0038] For the motor rotor of this embodiment, since filling grooves are respectively provided on the d-axis and the q-axis, the end ring 7 can be arranged in a cross shape, thereby facilitating the aluminum casting process.

[0039] In one embodiment, only the d-axis filling slot 3 is provided on the rotor core 1, and no q-axis filling slot is provided. Therefore, the slit slot 2 on the same layer can be set as a whole slot structure, extending from the outer circle of the rotor on one side of the q-axis to the outer circle of the rotor on the other side of the q-axis, thereby forming a larger area of ​​the slit slot 2, further enhancing the salient pole ratio of the motor.

[0040] In this embodiment, since the d-axis filling grooves 3 are only provided on both sides of the d-axis, the end ring 7 can be designed as a straight-line structure, so that the slit groove 2 has a larger flow area, further improving the heat dissipation capacity of the motor.

[0041] In one embodiment, the width of the dividing rib 5 along the d-axis direction is t, 0.5*σ≤t≤1.5σ, where σ is the air gap width between the stator and the rotor. Limiting the width of the dividing rib 5 can ensure the structural strength of the rotor without reducing the salient pole ratio.

[0042] In one embodiment, when the q-axis filling slot 4 is located between the outermost slit slot 2 and the outer circle of the rotor along the q-axis direction, at least one layer of q-axis filling slots 4 is arranged between the outermost slit slot 2 and the outer circle of the rotor, and the q-axis filling slot 4 is circular, elliptical or rectangular.

[0043] In one embodiment, the slit slot 2 is U-shaped or straight, and the slit slot 2 includes straight line segments and / or arc segments. Preferably, the slit slot 2 is U-shaped or a U-shaped structure. By designing the slit slot 2 to be a U-shaped structure, the difference in magnetic resistance between the d and q axes can be increased, thereby making more full use of the magnetic resistance torque.

[0044] When the slit slot 2 is set to a U-shaped or U-shaped structure, at least one layer of independent q-axis filling slot 4 is arranged between the outermost slit slot 2 away from the rotor shaft hole 6 and the outer circle of the rotor. The shape of the independent q-axis filling slot 4 is not limited to a rectangular or circular structure, and is preferably designed to be a rectangular structure. Since the slit slot 2 is selected to be designed as a U-shaped structure, there is a blank area between the outermost slit slot 2 and the outer circle of the rotor, and the filling slot can be arranged in this area to enhance the starting ability of the motor.

[0045] In one embodiment, all the filling slots are filled with conductive non-magnetic materials and short-circuited through the end ring 7 to form a squirrel cage structure. The conductive non-magnetic material is preferably metal aluminum or its alloy material; aluminum has good conductivity and low price, and is suitable for use in industrial motors and other fields. The conductive non-magnetic material can also be made of other materials such as copper. The self-short-circuited squirrel cage structure provides asynchronous torque during the motor starting stage to achieve self-starting of the motor.

[0046] In one embodiment, the total area of ​​the slit slots 2 not covered by the end ring 7 accounts for 50% to 80% of the total area of ​​the filling slots and the slit slots 2, that is, the total area of ​​the flow holes on the rotor core 1 accounts for 50% to 80% of the total area of ​​the rotor slots; the motor flow holes are in direct contact with the air, and the larger the area, the better the heat dissipation capacity of the motor.

[0047] In one embodiment, the rotor shaft hole 6 is circular, elliptical or polygonal. The shape of the rotor shaft hole 6 can be selected in combination with the internal space of the rotor, in order to improve the utilization rate of the rotor space.

[0048] According to an embodiment of the present application, a self-starting synchronous reluctance motor includes a motor rotor, which is the motor rotor described above.

[0049] 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.

[0050] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above are only preferred implementations of the present application. 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 application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A motor rotor, characterized in that: The invention comprises a rotor core (1), wherein a filling slot and a slit slot (2) are arranged on the rotor core (1), wherein the filling slot comprises a d-axis filling slot (3) arranged between the d-axis and the q-axis and close to the d-axis, and end rings (7) are arranged at both ends of the rotor core (1), wherein the end rings (7) cover the area where the d-axis filling slot (3) is located and avoid the area where the slit slot (2) is located; The slit slot (2) is arranged in the region in the q-axis direction, and the d-axis filling slot (3) leaves the positions of both ends of the slit slot (2) close to the outer circle of the rotor core (1), so that the ends of the slit slot (2) extend to the outer circle of the rotor core (1), and the width of the end of the slit slot (2) close to the outer circle of the rotor core (1) is greater than the width of the end of the slit slot (2) close to the rotor shaft hole (6); The rotor core (1) is also provided with a q-axis filling slot (4), the q-axis filling slot (4) is located on the q-axis, and the slit slot (2) is located on both sides of the q-axis filling slot (4); the rotor core (1) is also provided with another q-axis filling slot (4), the other q-axis filling slot (4) is located on the q-axis, and the other q-axis filling slot (4) is located between the outermost slit slot (2) along the q-axis direction and the outer circle of the rotor.

2. The motor rotor according to claim 1, characterized in that: Along the q-axis direction, the slit groove (2) is located outside the d-axis filling groove (3).

3. The motor rotor according to claim 1, characterized in that: The d-axis filling grooves (3) are arranged on both sides of the d-axis and are symmetrical about the q-axis.

4. The motor rotor according to claim 1, characterized in that: Between the rotor shaft hole (6) on one side of the q-axis and the outer circle of the rotor, the d-axis filling grooves (3) are arranged in n layers along the d-axis direction, and m d-axis filling grooves (3) are placed in each layer, where n≥2 and m≥2.

5. The motor rotor according to claim 1, characterized in that: The d-axis filling groove (3) is in the shape of an elongated strip.

6. The motor rotor according to claim 4, characterized in that: Along the direction away from the rotor shaft hole (6), the width of the d-axis filling groove (3) in the q-axis direction increases gradually.

7. The motor rotor according to claim 1, characterized in that: The slit groove (2) is located on both sides of the q-axis filling groove (4), and when the q-axis filling groove (4) and the corresponding slit groove (2) are arranged in the same layer, a dividing rib (5) is arranged between the slit groove (2) and the q-axis filling groove (4) in the same layer.

8. The motor rotor according to claim 7, characterized in that: The width of the dividing rib (5) along the d-axis direction is t, 0.5*σ≤t≤1.5σ, wherein σ is the width of the air gap between the stator and the rotor.

9. The motor rotor according to claim 1, characterized in that: When the q-axis filling groove (4) is located between the outermost slit groove (2) and the outer circle of the rotor along the q-axis direction, at least one layer of the q-axis filling groove (4) is arranged between the outermost slit groove (2) and the outer circle of the rotor, and the q-axis filling groove (4) is circular, elliptical or rectangular.

10. The motor rotor according to claim 1, characterized in that: The slit groove (2) is U-shaped or straight-line-shaped, and the slit groove (2) comprises a straight line segment and / or an arc segment.

11. The motor rotor according to claim 1, characterized in that: All the filling slots are filled with conductive and non-magnetic materials and are short-circuited and connected via end rings (7) to form a squirrel cage structure.

12. The motor rotor according to claim 1, characterized in that: The total area of ​​the slit groove (2) not covered by the end ring (7) accounts for 50% to 80% of the total area of ​​the filling groove and the slit groove (2).

13. The motor rotor according to claim 1, characterized in that: The rotor shaft hole (6) is circular, elliptical or polygonal.

14. The motor rotor according to claim 1, characterized in that: The slit grooves (2) located on the same layer are of a whole groove structure.

15. A self-starting synchronous reluctance motor, comprising a motor rotor, characterized in that: The motor rotor is the motor rotor according to any one of claims 1 to 14.

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