CN111313579A

CN111313579A - Lamination of permanent magnet motor stator core

Info

Publication number: CN111313579A
Application number: CN202010289075.1A
Authority: CN
Inventors: 张兆宇; 刘东旭
Original assignee: Dalian Zhi Ding Technology Co ltd
Current assignee: Dalian Zhi Ding Technology Co ltd
Priority date: 2020-04-14
Filing date: 2020-04-14
Publication date: 2020-06-19

Abstract

A lamination of a permanent magnet motor stator core belongs to the field of motors. Comprising a plurality of stator slots provided with cuts comprising a cut a and a cut B, the radial dimension of the cut a being greater than the radial dimension of the cut B. The slot wedge has at least two sizes of notches for installing slot wedges with corresponding sizes, wherein the larger notch A can bear larger stress, so that the safety is improved, and the service life is prolonged.

Description

Lamination of permanent magnet motor stator core

Technical Field

The invention relates to the field of motors, in particular to a lamination of a permanent magnet motor stator core.

Background

The stator core of the large permanent magnet motor is formed by overlapping a plurality of annular laminated sheets, stator slots on the annular laminated sheets are generally rectangular slots, notches with the same size are arranged on the side walls of stator teeth at the slot openings of the stator slots, and the notches are used for placing slot wedges to prevent conductors in the stator slots from being separated.

Disclosure of Invention

The invention provides a lamination of a permanent magnet motor stator core, which aims to solve the problem that potential safety hazards are easy to occur due to the fact that the sizes of the notches of the existing annular lamination are the same.

In order to achieve the purpose, the invention adopts the technical scheme that: a lamination of a permanent magnet motor stator core comprises a plurality of stator slots provided with cuts, wherein the cuts comprise a cut A and a cut B, and the radial dimension of the cut A is larger than that of the cut B.

Further, the midpoint of the notch circumferential length of the stator slot where the notch a is located is a point O1, the midpoint of the slot bottom circumferential length of the stator slot where the notch a is located is a point O2, and the direction vector starting from the point O1 to the point O2 or a vector component thereof is opposite to the direction of the gravity G.

Furthermore, the included angle between the direction vector and the gravity direction is more than 135 degrees.

Further, the number of the stator slots provided with the cuts a1 is 3N, and N is a constant.

Furthermore, the number of the stator slots with the cuts A is odd, the number of the stator slots with the cuts A on two sides of the vertical line where the center of the lamination is located is the same, and the cuts in the stator slots on the top of the vertical line are all the cuts A.

Further, the notch A and the notch B are both positioned at the notch of the stator slot in which the notch A and the notch B are positioned.

Furthermore, the cuts also comprise a cut D located in the middle of the corresponding stator slot, the stator slot in which the cut D is located is provided with a double-layer winding, and the distance H2 from the cut D to the bottom of the stator slot has the formula:

H2＝(ρ2/(ρ1+ρ2))×H1 (1)

wherein: h1 is the depth of the stator slot, ρ 1 is the resistivity of the winding conductor near the slot in the double layer winding, and ρ 2 is the resistivity of the winding conductor near the slot bottom in the double layer winding.

Further, the notches also comprise notches C located at the notches of the corresponding stator slots, the radial size of the notch A is larger than that of the notch C, and the radial size of the notch C is larger than that of the notch B.

Further, the number of the stator slots having both the cutouts C and B is 2.

The invention has the beneficial effects that: the notches with at least two sizes are used for installing the slot wedges with corresponding sizes, wherein the larger notch A can bear larger stress, so that the safety and the service life are improved.

Drawings

FIG. 1 is a schematic view of the construction of an annular lamination of the present invention;

FIG. 2 is a schematic representation of the radial dimensions of the present invention;

FIG. 3 is a schematic view of the present invention;

FIG. 4 is a schematic view of the present invention;

FIG. 5 is a schematic view of the present invention.

In the figure, 1 is a notch A, 2 is a notch B, 3 is a notch C, 4 is a notch D, and 5 is a stator slot.

Detailed Description

The stator core of the permanent magnet motor of the present embodiment is formed by stacking a plurality of annular laminated sheets, each annular laminated sheet is a circular ring structure (as shown in fig. 1, a shaded portion is a stator section) formed by sequentially arranging a plurality of fan-shaped stator sections, each stator section is provided with a stator slot 5 having a slot depth of H1, and two sides of each stator slot 5 are provided with triangular notches for placing slot wedges, so as to prevent conductors in the stator slots 5 from coming off.

In use, the annular lamination is vertically placed, and the cuts on the annular lamination comprise a cut A1, a cut B2, a cut C3 and a cut D4 which are arranged at the notch of the stator slot 5.

The radial dimension L of the notch at the notch is as follows: the radial dimension of the notch A1 is larger than that of the notch C3, the radial dimension of the notch C3 is larger than that of the notch B2, the midpoint of the circumferential length of the notch of the stator slot 5 where the notch A1 is located is a point O1, the midpoint of the circumferential length of the slot bottom of the stator slot 5 where the notch A1 is located is a point O2, the direction vector from the point O1 to the point O2 is opposite to the direction of gravity G, the included angle between the direction vector and the direction of gravity is more than 135 degrees, because the gravity and the electromagnetic pulling force applied to the winding above the horizontal line where the center of the annular lamination is located are downward, the notch A1 with larger size needs to be arranged to be mounted with a thicker slot wedge to ensure safety, the inter-turn insulation thickness of the conductor in the stator slot 5 is smaller than that of the conductors in other stator slots 5, and the conductors in the stator slot 5 can be connected as the winding on the side of the center point of the motor winding, but not for connecting motor leads (for connecting the inverter supply), the number of stator slots 5 with cut a1 on the annular lamination is 3N, N is a constant, the preferred number of stator slots 5 with cut a1 is odd, and the number of stator slots 5 with cut a1 on both sides of the vertical line where the center of the annular lamination is located is the same, and the cuts in the stator slots 5 at the top of the vertical line are both cut a 1;

the different cuts in the annular lamination thus have the following arrangements:

mode 1: the notches A1 are arranged in the stator slots above the horizontal line where the centers of the annular laminations are located, the notches A1 in each stator slot are arranged in pairs, the notches B2 are arranged in the stator slots below the horizontal line, and the notches B2 in each stator slot are arranged in pairs;

mode 2: the top-to-bottom cuts on either side of a vertical line with the center of the annular lamination are arranged as follows: the transition from the notch a1 to the notch B2 is performed through the notch C3, the notch C3 performs the transition, the number of the stator slots 5 having both the notch C3 and the notch B2 on the annular lamination is 2, and preferably, the included angle between the direction vector and the gravity direction is 135 degrees or more.

An upper double-layer winding and a lower double-layer winding are arranged in the stator slot 5 where the notch D4 is located, an insulation slot wedge placed in the notch D4 plays a role in dividing the double-layer winding and also plays a role in local support, and the distance H2 from the notch D4 to the bottom of the stator slot 5 is defined by the following formula:

H2＝(ρ2/(ρ1+ρ2))×H1(1)

wherein: rho 1 is the resistivity of a winding conductor close to the notch in the double-layer winding, and rho 2 is the resistivity of a winding conductor close to the bottom of the slot in the double-layer winding; both sides of the stator slot 5 may be provided with a notch D4, or one side thereof may be provided with a notch D4.

Therefore, the notch D4 may be provided on the side of the notch a1, on the side of the notch B2, or on the side of the notch C3; further, when the notch a1 and the notch B2 are provided in one stator slot 5, it is preferable that the notch D4 is provided on the side of the notch B2, and the sum of the radial dimension of the notch D4 and the radial dimension of the notch B2 is equal to or larger than the radial dimension of the notch a 1.

At least one of the cut A1, the cut B2, the cut C3, and the cut D4 is a right triangle.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be able to cover the technical solutions and the inventive concepts of the present invention within the technical scope of the present invention.

Claims

1. A lamination for a stator core of a permanent magnet electrical machine, comprising a plurality of stator slots (5) provided with cut-outs, characterized in that the cut-outs comprise a cut-out a (1) and a cut-out B (2), the radial dimension of the cut-out a (1) being larger than the radial dimension of the cut-out B (2).

2. The lamination of the stator core of the permanent magnet motor according to claim 1, wherein the midpoint of the slot opening circumferential length of the stator slot (5) where the notch A (1) is located is a point O1, the midpoint of the slot bottom circumferential length of the stator slot (5) where the notch A (1) is located is a point O2, and the direction vector starting from the point O1 to the point O2 is opposite to the direction of gravity G.

3. The lamination of a stator core of a permanent magnet electric machine according to claim 2, wherein the angle between the direction vector and the direction of gravity is above 135 degrees.

4. A lamination for a stator core of a permanent magnet machine according to claim 2, characterized in that the number of stator slots (5) provided with cuts a1 is 3N, N being a constant.

5. A lamination stack for a stator core of a permanent magnet motor according to claim 2, characterized in that the number of stator slots (5) with cut-outs a (1) is odd and the number of stator slots (5) with cut-outs a (1) on both sides of a vertical line where the center of the lamination stack is located is the same and the cut-outs in the stator slots (5) at the top of the vertical line are all cut-outs a (1).

6. A lamination of a stator core of a permanent magnet machine according to claim 1, characterized in that the cut-outs a (1) and B (2) are located at the notches of the stator slots (5) where they are located.

7. A lamination for a stator core of a permanent magnet motor according to claim 6, characterized in that the cut-outs further comprise a cut-out D (4) located in the middle of the corresponding stator slot (5), the stator slot (5) in which the cut-out D (4) is located is provided with a double layer winding, and the distance H2 from the cut-out D (4) to the bottom of the stator slot (5) is given by the formula:

H2＝(ρ2/(ρ1+ρ2))×H1 (1)

wherein: h1 is the depth of the stator slot (5), ρ 1 is the resistivity of the winding conductor near the slot in a double layer winding, and ρ 2 is the resistivity of the winding conductor near the slot bottom in a double layer winding.

8. A lamination for a stator core of a permanent magnet motor according to claim 6, characterized in that the cut-outs further comprise cut-outs C (3) at the slot mouths of the corresponding stator slots (5), the radial dimension of the cut-outs A (1) being larger than the cut-outs C (3), the radial dimension of the cut-outs C (3) being larger than the cut-outs B (2).

9. A lamination for a stator core of a permanent magnet motor according to claim 6, characterized in that the number of stator slots (5) having both said C (3) and B (2) cut-outs is 2.