CN210985754U - Stator punching sheet with large and small slots - Google Patents
Stator punching sheet with large and small slots Download PDFInfo
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- CN210985754U CN210985754U CN201921057992.6U CN201921057992U CN210985754U CN 210985754 U CN210985754 U CN 210985754U CN 201921057992 U CN201921057992 U CN 201921057992U CN 210985754 U CN210985754 U CN 210985754U
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Abstract
A stator punching sheet with large and small slots belongs to the technical field of three-phase asynchronous motors and solves the technical problems of reducing stray loss of the three-phase asynchronous motors, reducing temperature rise and noise of the motors and improving motor efficiency. The solution is as follows: at least six groups of stator slot groups for placing copper wires are radially and uniformly arranged on the annular surface of the substrate along the circumferential direction of the substrate according to the motor stage number, the number of slots of each pole and each phase in each group of stator slot groups is five or three, each stator slot group comprises a large stator slot, a middle stator slot and a small stator slot, the area of the small stator slot is 80% -95% of that of the large stator slot, and the area of the middle stator slot is between that of the large stator slot and that of the small stator slot. The utility model discloses a big stator slot in the design stator slot group, well stator slot and little stator slot's flute profile distribute, can make the groove utilization ratio improve greatly, improve the stator towards the distribution mechanism of piece yoke portion magnetism density.
Description
Technical Field
The utility model belongs to the technical field of the three-phase asynchronous motor, concretely relates to big small groove stator towards piece.
Background
The three-phase asynchronous motor includes five losses, namely stator copper loss, rotor copper loss, iron core loss, mechanical loss and stray loss. In order to enable the motor efficiency to reach different levels of high efficiency, super high efficiency and the like, the technical personnel in the field analyze and judge various losses and take corresponding measures to reduce the losses.
The stator coil adopts the low harmonic winding form of unequal turns, not only can make the actual resistance of winding reduce, reaches the purpose that reduces stator copper loss, carries out analysis, judgement and selection to the harmonic of different turns moreover to the stray loss that effectual reduction motor produced because the harmonic. In the face of different numbers of turns of each coil, the same groove shape of the stator punching sheet can cause different groove filling rates. Therefore, the design of the large and small groove punching sheets is carried out at the same time. On one hand, in order to optimize the wire inserting manufacturability, the full rate of each groove is basically consistent, and the wire inserting quality is effectively improved; on the other hand, the sizes of the same stamped sheet and the slots corresponding to different yokes are further refined through precise design and test requirements for reducing motor stray loss and motor temperature rise, reducing noise and the like.
SUMMERY OF THE UTILITY MODEL
The utility model discloses a technical level of current stator punching slice groove shape design is developed and is improved, effectual reduction three-phase asynchronous motor's stray loss, reduces the temperature rise and the noise of motor, improves motor efficiency. The utility model provides a every looks slot number of every level is three or five big or small groove stator towards piece.
The utility model discloses a following technical scheme realizes.
A big and small slot stator punching sheet comprises a circular ring-shaped substrate, wherein: at least six groups of stator slot groups for placing copper wires are radially and uniformly arranged on the annular surface of the substrate along the circumferential direction of the substrate according to the motor stage number, the number of slots of each pole and each phase in each group of stator slot groups is five, each stator slot group comprises a large stator slot and a small stator slot, the area of the small stator slot is 80% -95% of that of the large stator slot, and the slot shape distribution of the large stator slot and the small stator slot in the stator slot group is one or two of the following slot shape distribution forms:
1) the large stator slot is arranged in the middle of the stator slot group, and two small stator slots are symmetrically arranged on two sides of the large stator slot respectively;
2) the three large stator slots are arranged in the middle of the stator slot group, and two sides of the three large stator slots are respectively symmetrically provided with a small stator slot;
the large stator slot or the small stator slot comprises a rectangular slot, a first isosceles trapezoid slot, a second isosceles trapezoid slot and a semicircular slot, one end, close to the inner circular surface of the substrate, of the large stator slot or the small stator slot is provided with the rectangular slot, the width of the rectangular slot is 2.5-4.2 mm, and the height of the rectangular slot is 0.9-2.0 mm; the second isosceles trapezoid groove is arranged at one end, far away from the circle center, of the first isosceles trapezoid groove, the upper bottom edge of the first isosceles trapezoid groove is collinear with the long edge of the rectangular groove, the lower bottom edge of the first isosceles trapezoid groove is collinear with the upper bottom edge of the second isosceles trapezoid groove, the width of the lower bottom edge of the first isosceles trapezoid groove is 5-10 mm, the included angle between the bevel edge and the lower bottom edge of the first isosceles trapezoid groove is 20-30 degrees, the width of the lower bottom edge of the second isosceles trapezoid groove is 8-15 mm, and the height of the second isosceles trapezoid groove is 12-40 mm; the semicircular groove is formed in the position of the lower bottom edge of the second isosceles trapezoid groove, and the diameter of the semicircular groove is equal to the width of the lower bottom edge of the second isosceles trapezoid groove.
Furthermore, the stator slot group is also provided with middle stator slots, the large stator slots are arranged in the middle of the stator slot group, the two small stator slots are symmetrically arranged on two sides of the stator slot group about the circle center, the two middle stator slots are symmetrically arranged between the large stator slot and the small stator slots, the distances between the adjacent large stator slot, the small stator slot and the middle stator slot are equal, and the area of the middle stator slot is between the area of the small stator slot and the area of the large stator slot.
Furthermore, 8-16 buckle piece grooves used for installing buckle pieces are uniformly arranged on the outer circular surface of the substrate along the circumferential direction of the substrate, the lower bottom edge of each buckle piece groove is a straight line, the upper bottom edge of each buckle piece groove is naturally opened along the circumferential direction of the substrate, a piece arranging groove is arranged at the bottom of any buckle piece groove, and the piece arranging groove is rectangular or trapezoidal.
Further, 15 × n stator slots are uniformly distributed on the inner circular ring surface of the substrate in a radial mode along the circumferential direction of the substrate, wherein n is the number of poles of the motor.
Further, the width of cramp groove is 14 ~ 25mm, and highly is 3 ~ 5mm, and the contained angle between cramp groove hypotenuse and the base is 15 ~ 25.
Furthermore, the number of each phase slot of each pole in the stator slot group is three, one large stator slot is arranged in the middle of the stator slot group, and two small stator slots are symmetrically arranged on two sides of the large stator slot respectively.
Compared with the prior art, the beneficial effects of the utility model are that:
the utility model provides a pair of big small groove stator punching, it is great to the rule manufacturability and the rule quality promotion of coil of not waiting for turns, to the efficiency that promotes the motor, improve start, reduce motor noise meaning great. The slot utilization rate can be greatly improved, and the distribution mechanism of the magnetic density of the yoke part of the stator punching sheet is improved. The stray loss of the motor is reduced, the starting performance of the motor is improved, the temperature rise of the motor is reduced, the efficiency of the motor is improved, and the overall cost of the motor is saved.
Drawings
Fig. 1 is a schematic view of the overall structure of a stator slot with the number of slots per phase of each pole being 5 in the first embodiment.
Fig. 2 is a partially enlarged and superimposed groove-shaped comparative structure schematic diagram of the part I and the part ii in fig. 1, in which the two-dot chain line is a groove-shaped outline of a small stator groove.
Fig. 3 is a partially enlarged structural view of a buckle sheet groove and a sheet tidying groove at the part III in fig. 1.
FIG. 4 is a schematic view of the overall structure of the stator slots of 5 slots per pole and phase in the second embodiment.
Fig. 5 is a partially enlarged and superimposed groove-shaped comparative structure schematic diagram of the part I and the part ii in fig. 4, in which the two-dot chain line is a groove-shaped outline of the small stator groove.
FIG. 6 is a schematic view of the overall structure of the stator slots of 5 slots per pole and phase in the third embodiment.
Fig. 7 is a partially enlarged and superimposed groove-shaped comparative structure schematic diagram of the parts I, ii and iii in fig. 6, in which the two-dot chain line is a groove-shaped contour line of the small stator groove and the dotted line is a groove-shaped contour line of the middle stator groove.
FIG. 8 is a schematic view of the overall structure of the stator slots of 3 slots per phase per pole in the fourth embodiment.
Fig. 9 is a partially enlarged and superimposed groove-shaped comparative structure schematic diagram of the part I and the part ii in fig. 8, in which the two-dot chain line is a groove-shaped outline of the small stator groove.
In the figure, 1 is a substrate, 2 is a stator slot group, 21 is a rectangular slot, 22 is a first isosceles trapezoid-shaped slot, 23 is a second isosceles trapezoid-shaped slot, 24 is a semicircular slot, 25 is a small stator slot, 26 is a large stator slot, 27 is a middle stator slot, 3 is a buckle slot, and 4 is a piece arranging slot.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples.
Example one
A stator punching sheet with large and small slots comprises a substrate 1 in a ring shape, wherein: at least six stator slot groups 2 for placing copper wires are radially and uniformly arranged on the annular surface of the substrate 1 along the circumferential direction of the substrate 1 according to the motor stage number, the number of slots of each pole and each phase in each stator slot group 2 is five, each stator slot group 2 comprises a large stator slot 26 and a small stator slot 25, the groove shape and the area of all the large stator slots 26 in one stator punching sheet are equal, the groove shape and the area of all the small stator slots 25 are equal, and the groove shape of the large stator slot 26 or the small stator slot 25 is an open slot, so that the copper wires can be placed conveniently; the area of the small stator slot 25 is 80% -95% of the area of the large stator slot 26, the large stator slot 26 and the small stator slot 25 in the stator slot group 2 are distributed in a slot shape as shown in fig. 1-3, one large stator slot 26 is arranged in the middle of the stator slot group 2, two small stator slots 25 are symmetrically arranged on two sides of the large stator slot 26, namely, the large stator slot 26 and the small stator slot 25 of five slots in each phase of each pole are distributed in a small-large-small mode;
the basic groove shape of the large stator groove 26 or the small stator groove 25 is a pear-shaped groove and comprises a rectangular groove 21, a first isosceles trapezoid-shaped groove 22, a second isosceles trapezoid-shaped groove 23 and a semicircular groove 24, one end, close to the inner circular surface of the substrate 1, of the rectangular groove 21 is arranged, the width of the rectangular groove 21 is 2.5-4.2 mm, and the height of the rectangular groove 21 is 0.9-2.0 mm; the second isosceles trapezoid-shaped groove 23 is arranged at one end, far away from the center of a circle, of the first isosceles trapezoid-shaped groove 22, the upper bottom edge of the first isosceles trapezoid-shaped groove 22 is collinear with the long edge of the rectangular groove 21, the lower bottom edge of the first isosceles trapezoid-shaped groove 22 is collinear with the upper bottom edge of the second isosceles trapezoid-shaped groove 23, the width of the lower bottom edge of the first isosceles trapezoid-shaped groove 22 is 5-10 mm, the included angle between the oblique edge and the lower bottom edge of the first isosceles trapezoid-shaped groove 22 is 20-30 degrees, the width of the lower bottom edge of the second isosceles trapezoid-shaped groove 23 is 8-15 mm, and the height of the second isosceles trapezoid-shaped groove 23 is 12-40; the semi-circular groove 24 is arranged at the position of the lower bottom edge of the second isosceles trapezoid-shaped groove 23, and the diameter of the semi-circular groove 24 is equal to the width of the lower bottom edge of the second isosceles trapezoid-shaped groove 23.
Furthermore, 8-16 cramp grooves 3 for installing cramps are uniformly arranged on the outer circumferential surface of the substrate 1 along the circumferential direction of the substrate 1 to play a role of fixing an iron core, the cramp grooves are similar to isosceles trapezoids, the lower bottom edges of the cramp grooves 3 are arranged into straight lines, the upper bottom edges of the cramp grooves 3 are naturally opened along the circumferential direction of the substrate 1, a piece arranging groove 4 is arranged at the bottom of any one of the cramp grooves 3, the piece arranging groove 4 is rectangular or trapezoidal, the piece arranging groove 4 is used for laminating the stator iron core to ensure that the punching sheet has consistent directionality, the width of the upper bottom edge of the piece arranging groove 4 is 3-4 mm, and the height is 1.5-4 mm;
further, the large stator slots 26 and the small stator slots 25 in the stator slot group 2 are uniformly arranged with 15 × n, i.e., 3 (phases) × 5 (number of slots per pole per phase) × n, on the inner circular ring surface of the substrate 1 radially in the circumferential direction of the substrate 1, where n is the number of poles of the motor.
Further, the width of the buckle piece groove 3 is 14-25 mm, the height is 3-5 mm, and the included angle between the inclined edge and the bottom edge of the buckle piece groove 3 is 15-25 degrees.
The method comprises the steps of collecting test data of the three-phase asynchronous motor using the stator punching sheet with the large and small slots with the number of 5 slots per pole and phase, saving copper at 0.1-0.25 Kg/KW, and enabling motor efficiency to meet and be slightly higher than standard IE2 and IE3 efficiency values.
Example two
The large stator slots 26 and the small stator slots 25 in the stator slot group 2 are distributed in a slot shape as shown in fig. 4 and 5, three large stator slots 26 are arranged in the middle of the stator slot group 2, two sides of the three large stator slots 26 are respectively and symmetrically provided with one small stator slot 25, namely, the large stator slots 26 and the small stator slots 25 of five slots in each phase of each pole are distributed in a 'small-large-small' shape.
The method comprises the steps of collecting test data of the three-phase asynchronous motor using the stator punching sheet with the large and small slots with the number of 5 slots per pole and phase, saving copper at 0.1-0.25 Kg/KW, and enabling motor efficiency to meet and be slightly higher than standard IE2 and IE3 efficiency values.
EXAMPLE III
As shown in fig. 6 and 7, in the third embodiment, the stator slot group 2 is further provided with middle stator slots 27, and the slot shapes of the large stator slot 26, the small stator slot 25 and the middle stator slot 27 in the stator slot group 2 are distributed as follows: one large stator slot 26 is arranged in the middle of the stator slot group 2, two small stator slots 25 are symmetrically arranged on two sides of the stator slot group 2 about the circle center, two middle stator slots 27 are symmetrically arranged between the large stator slot 26 and the small stator slots 25, the distances between the adjacent large stator slot 26, the small stator slot 25 and the middle stator slot 27 are equal, namely the large stator slot 26, the small stator slot 25 and the middle stator slot 27 of five slots in each phase of each pole are distributed in a small-middle-large-middle-small mode, the area of the small stator slot 25 is 80% -95% of the area of the large stator slot 26, and the area of the middle stator slot 27 is between the area of the small stator slot 25 and the area of the large stator slot 26.
The method comprises the steps of collecting test data of the three-phase asynchronous motor using the stator punching sheet with the large and small slots with the number of 5 slots per pole and phase, saving copper at 0.1-0.25 Kg/KW, and enabling motor efficiency to meet and be slightly higher than standard IE2 and IE3 efficiency values.
Example four
The large stator slot 26 and the small stator slot 25 in the stator slot group 2 are distributed in a slot shape as shown in fig. 8 and 9, one large stator slot 26 is arranged in the middle of the stator slot group 2, and two sides of the large stator slot 26 are respectively symmetrically provided with one small stator slot 25, namely, the large stator slot 26 and the small stator slot 25 of three slots of each phase of each pole are distributed in a small-large-small mode.
The method is characterized in that test data of the three-phase asynchronous motor using the stator punching sheet with the large and small slots with the number of slots of each pole and each phase being 3 are collected, the copper is saved at 0.1-0.25 Kg/KW, and the motor efficiency meets and is slightly higher than the efficiency values of standards IE2 and IE 3.
The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (6)
1. The utility model provides a big small groove stator punching, it includes ring shape's substrate (1), its characterized in that: at least six groups of stator slot groups (2) for placing copper wires are radially and uniformly arranged on the annular surface of the substrate (1) along the circumferential direction of the substrate (1) according to the motor stage number, the number of slots of each pole and each phase in each group of stator slot groups (2) is five, each stator slot group (2) comprises a large stator slot (26) and a small stator slot (25), the area of the small stator slot (25) is 80-95% of the area of the large stator slot (26), and the slot distribution of the large stator slot (26) and the small stator slot (25) in the stator slot group (2) is one or two of the following slot distribution forms:
1) a large stator slot (26) is arranged in the middle of the stator slot group (2), and two small stator slots (25) are symmetrically arranged on two sides of the large stator slot (26) respectively;
2) the three large stator slots (26) are arranged in the middle of the stator slot group (2), and two sides of the three large stator slots (26) are respectively and symmetrically provided with a small stator slot (25);
the large stator groove (26) or the small stator groove (25) comprises a rectangular groove (21), a first isosceles trapezoid-shaped groove (22), a second isosceles trapezoid-shaped groove (23) and a semicircular groove (24), one end, close to the inner circular surface of the substrate (1), of the large stator groove (26) or the small stator groove is provided with the rectangular groove (21), the width of the rectangular groove (21) is 2.5-4.2 mm, and the height of the rectangular groove (21) is 0.9-2.0 mm; the second isosceles trapezoid groove (23) is arranged at one end, far away from the center of a circle, of the first isosceles trapezoid groove (22), the upper bottom edge of the first isosceles trapezoid groove (22) is collinear with the long edge of the rectangular groove (21), the lower bottom edge of the first isosceles trapezoid groove (22) is collinear with the upper bottom edge of the second isosceles trapezoid groove (23), the width of the lower bottom edge of the first isosceles trapezoid groove (22) is 5-10 mm, the included angle between the bevel edge and the lower bottom edge of the first isosceles trapezoid groove (22) is 20-30 degrees, the width of the lower bottom edge of the second isosceles trapezoid groove (23) is 8-15 mm, and the height of the second isosceles trapezoid groove (23) is 12-40 mm; the semicircular groove (24) is arranged at the position of the lower bottom edge of the second isosceles trapezoid groove (23), and the diameter of the semicircular groove (24) is equal to the width of the lower bottom edge of the second isosceles trapezoid groove (23).
2. The large and small slot stator punching sheet of claim 1, characterized in that: the stator slot group (2) is further provided with middle stator slots (27), the large stator slots (26) are arranged in the middle of the stator slot group (2), the two small stator slots (25) are symmetrically arranged on two sides of the stator slot group (2) relative to the circle center, the two middle stator slots (27) are symmetrically arranged between the large stator slots (26) and the small stator slots (25), the distances among the adjacent large stator slots (26), the small stator slots (25) and the middle stator slots (27) are equal, and the area of the middle stator slots (27) is between the area of the small stator slots (25) and the area of the large stator slots (26).
3. The large and small slot stator punching sheet of claim 1, characterized in that: the outer disc of substrate (1) is gone up and is evenly arranged 8 ~ 16 buckle piece grooves (3) that are used for installing the buckle piece along the circumferencial direction of substrate (1), the lower base of buckle piece groove (3) sets up to the straight line, and the upper base of buckle piece groove (3) is along the circumferencial direction natural opening of substrate (1), is provided with reason piece groove (4) in the bottom of arbitrary buckle piece groove (3) wherein, the shape of reason piece groove (4) is rectangle or trapezoidal.
4. The large and small slot stator punching sheet of claim 3, characterized in that: the width of the buckle piece groove (3) is 14-25 mm, the height is 3-5 mm, and the included angle between the bevel edge and the bottom edge of the buckle piece groove (3) is 15-25 degrees.
5. The stator punching sheet with the large and small slots as claimed in claim 1, wherein the large stator slots and the small stator slots in the stator slot group (2) are uniformly distributed with 15 × n in a radial manner on the inner circular ring surface of the substrate (1) along the circumferential direction of the substrate (1), wherein n is the number of poles of the motor.
6. The large and small slot stator punching sheet of claim 1, characterized in that: the number of each phase slot of each pole in the stator slot group (2) is three, one large stator slot (26) is arranged in the middle of the stator slot group (2), and two small stator slots (25) are symmetrically arranged on two sides of the large stator slot (26) respectively.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921057992.6U CN210985754U (en) | 2019-07-09 | 2019-07-09 | Stator punching sheet with large and small slots |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921057992.6U CN210985754U (en) | 2019-07-09 | 2019-07-09 | Stator punching sheet with large and small slots |
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| CN210985754U true CN210985754U (en) | 2020-07-10 |
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| CN201921057992.6U Active CN210985754U (en) | 2019-07-09 | 2019-07-09 | Stator punching sheet with large and small slots |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021004251A1 (en) * | 2019-07-09 | 2021-01-14 | 山西电机制造有限公司 | Stator lamination having slots of unequal size for use in three-phase asynchronous motor having low harmonic wave windings having unequal number of turns |
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2019
- 2019-07-09 CN CN201921057992.6U patent/CN210985754U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021004251A1 (en) * | 2019-07-09 | 2021-01-14 | 山西电机制造有限公司 | Stator lamination having slots of unequal size for use in three-phase asynchronous motor having low harmonic wave windings having unequal number of turns |
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