CN112134375B

CN112134375B - Stator module and motor

Info

Publication number: CN112134375B
Application number: CN202010959057.XA
Authority: CN
Inventors: 薛建; 李家乐; 吴根城; 王立军; 汤秀清
Original assignee: Guangzhou Haozhi Electromechanical Co Ltd
Current assignee: Guangzhou Haozhi Electromechanical Co Ltd
Priority date: 2020-09-14
Filing date: 2020-09-14
Publication date: 2021-09-21
Anticipated expiration: 2040-09-14
Also published as: CN112134375A

Abstract

The invention discloses a stator assembly and a motor, comprising: a stator core having a cylindrical shape; the coil winding comprises a plurality of coil winding units, the coil winding units are tightly arranged on the inner wall surface of the stator core along the circumferential direction, the coil winding units are encapsulated by potting adhesive and form an integral assembly with the stator core, and a plurality of coil winding units limit a rotor space in the stator core. The stator core is in a cylindrical shape, and the plurality of coil winding units are tightly arranged on the inner wall surface of the stator core along the circumferential direction, and because the core tooth grooves of the conventional stator core are not arranged, the tooth groove additional torque of the motor is eliminated, so that the motor achieves the tooth groove-free additional torque, and the running performance of the motor is improved. The coil winding units are arranged orderly, a large amount of space can be saved, the effective sectional area of a coil conducting wire is increased under the same condition, the electricity density of the stator winding is reduced, the copper loss of the stator is reduced, and the motor efficiency is improved.

Description

Stator module and motor

Technical Field

The invention is used in the field of motors, and particularly relates to a stator assembly and a motor.

Background

The stator iron core of the permanent magnet synchronous motor stator on the market at present adopts a structure with tooth grooves, so that the motor can generate harmful tooth groove additional torque.

The coil winding of the permanent magnet synchronous motor stator on the market at present adopts the bulk coil winding, the coil is distributed in a distributed mode, and the height of the wire end of the coil winding is very high, so that the leakage reactance of the end part of the coil winding is very high, the copper weight of an enameled wire is also relatively large, and the slot fullness rate cannot exceed 70%; since the wire end height of such a winding is relatively high, it also takes up relatively much space of the motor.

The magnetic circuit of the magnetic steel of the permanent magnet synchronous motor rotor on the market at present all passes through the yoke part of the rotor, so that magnetic pressure drop is generated at the yoke part of the rotor, partial magnetic flux is lost, and the overall efficiency of the motor and the heating of the motor are influenced.

Disclosure of Invention

The invention aims to at least solve one of the technical problems in the prior art, and provides a stator assembly and a motor, which effectively solve the problem that the cogging torque of the stator assembly is harmful to the motor and improve the motor efficiency.

The technical scheme adopted by the invention for solving the technical problems is as follows:

in a first aspect, a stator assembly, comprises:

a stator core having a cylindrical shape;

the coil winding comprises a plurality of coil winding units, the coil winding units are tightly arranged on the inner wall surface of the stator core along the circumferential direction, the coil winding units are encapsulated by potting adhesive and form an integral assembly with the stator core, and a plurality of coil winding units limit a rotor space in the stator core.

With reference to the first aspect, in certain implementations of the first aspect, the coil winding unit is a formed winding, the coil winding unit has an outer arc surface attached to an inner wall surface of the stator core, and a length of the stator core is not less than a length of the coil winding unit.

With reference to the first aspect and the foregoing implementation manners, in some implementation manners of the first aspect, the stator core is formed by laminating and welding annular silicon steel sheets.

In a second aspect, an electric machine comprises:

the stator assembly of any implementation of the first aspect;

a rotor assembly disposed in the rotor space.

With reference to the second aspect, in certain implementations of the second aspect, the rotor assembly includes:

a rotor core;

the magnetic steel is connected to the rotor core and comprises a magnetic steel N, a magnetic steel S and first transition magnetic steel, the magnetic steel N and the magnetic steel S are alternately distributed along the circumferential direction of the rotor core, the first transition magnetic steel is located between the adjacent magnetic steel N and the magnetic steel S, and the magnetizing direction of the first transition magnetic steel is consistent with the direction of the magnetic line of force passing through the first transition magnetic steel.

With reference to the first aspect and the foregoing implementation manners, in some implementation manners of the first aspect, the outer peripheral surface of the rotor core is provided with a plurality of first magnetic steel grooves, and the magnetic steel N, the magnetic steel S, and the first transition magnetic steel are surface-mounted in the first magnetic steel grooves.

With reference to the first aspect and the foregoing implementation manners, in some implementation manners of the first aspect, a plurality of second magnetic steel slots are axially formed in the rotor core, and the magnetic steel N, the magnetic steel S, and the first transition magnetic steel are inserted into the second magnetic steel slots.

With reference to the first aspect and the foregoing implementation manners, in some implementation manners of the first aspect, a plurality of third magnetic steel slots are formed in a yoke portion of the rotor core along a circumferential direction, a second transition magnetic steel magnetized in a normal direction is arranged in the third magnetic steel slots, and a magnetizing direction of the second transition magnetic steel is consistent with a direction in which a magnetic line of force passes through the yoke portion of the rotor core.

With reference to the first aspect and the foregoing implementation manners, in some implementation manners of the first aspect, the second transition magnetic steel is tile-shaped, and a plurality of second transition magnetic steels are distributed on the same circumference.

With reference to the first aspect and the foregoing implementation manners, in some implementation manners of the first aspect, the magnetic steel N and the magnetic steel S are axially divided into a plurality of segments.

One of the above technical solutions has at least one of the following advantages or beneficial effects:

the stator core is in a cylindrical shape, and the plurality of coil winding units are tightly arranged on the inner wall surface of the stator core along the circumferential direction, and because the core tooth grooves of the conventional stator core are not arranged, the tooth groove additional torque of the motor is eliminated, so that the motor achieves the tooth groove-free additional torque, and the running performance of the motor is improved.

The coil winding units are arranged orderly, a large amount of space can be saved, the effective sectional area of a coil conducting wire is increased under the same condition, the electricity density of the stator winding is reduced, the copper loss of the stator is reduced, and the motor efficiency is improved.

The stator iron core is cylindrical, and no tooth part occupies the space of the iron core, so that the effective placing space of the coil winding is increased, the effective sectional area of the winding enameled wire is increased, the electric density of the stator winding is reduced, the efficiency of the motor is improved, and the temperature rise of the motor is reduced.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural view of a first embodiment of the motor of the present invention;

FIG. 2 is a cross-sectional view taken at A-A in FIG. 1;

FIG. 3 is a schematic structural view of a second embodiment of the motor of the present invention;

FIG. 4 is a schematic view of the stator assembly of the embodiment of FIG. 1;

FIG. 5 is a cross-sectional view taken at B-B of FIG. 4;

FIG. 6 is a cross-sectional view of a stator core of the embodiment shown in FIG. 1;

FIG. 7 is a cross-sectional view of a stator core of the embodiment of FIG. 1;

FIG. 8 is a schematic diagram of the structure of a coil winding unit of the embodiment shown in FIG. 1;

FIG. 9 is a schematic view of the structure of the rotor assembly of the embodiment shown in FIG. 1;

FIG. 10 is a cross-sectional view taken at C-C of FIG. 9;

FIG. 11 is a schematic view of the structure of the rotor assembly of the embodiment shown in FIG. 3;

FIG. 12 is a schematic view of a rotor core construction of the embodiment of FIG. 1;

fig. 13 is a schematic view of a rotor core structure according to the embodiment shown in fig. 3.

Detailed Description

Reference will now be made in detail to the present preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.

In the present invention, if directions (up, down, left, right, front, and rear) are described, it is only for convenience of describing the technical solution of the present invention, and it is not intended or implied that the technical features referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, it is not to be construed as limiting the present invention.

In the invention, the meaning of "a plurality" is one or more, the meaning of "a plurality" is more than two, and the terms of "more than", "less than", "more than" and the like are understood to exclude the number; the terms "above", "below", "within" and the like are understood to include the instant numbers. In the description of the present invention, if there is description of "first" and "second" only for the purpose of distinguishing technical features, it is not to be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or implicitly indicating the precedence of the indicated technical features.

In the present invention, unless otherwise specifically limited, the terms "disposed," "mounted," "connected," and the like are to be understood in a broad sense, and for example, may be directly connected or indirectly connected through an intermediate; can be fixedly connected, can also be detachably connected and can also be integrally formed; may be mechanically coupled, may be electrically coupled or may be capable of communicating with each other; either as communication within the two elements or as an interactive relationship of the two elements. The specific meaning of the above-mentioned words in the present invention can be reasonably determined by those skilled in the art in combination with the detailed contents of the technical solutions.

Referring to fig. 1, 2, and 3, an embodiment of the present invention provides an electric machine including a stator assembly 1 and a rotor assembly 2.

Referring to fig. 4 and 5, the stator assembly 1 includes a stator core 11 and a coil winding. Referring to fig. 6 and 7, the stator core 11 extends in the axial direction, and the stator core 11 is cylindrical. Referring to fig. 4, 5, and 8, the coil winding includes a plurality of coil winding units 12, the plurality of coil winding units 12 are closely arranged on an inner wall surface of the stator core 11 along a circumferential direction, the plurality of coil winding units 12 are encapsulated by an encapsulating compound 13 and form an integral assembly with the stator core 11, the plurality of coil winding units 12 define a rotor space inside the stator core 11, and the rotor assembly 2 is disposed in the rotor space.

The potting adhesive 13 is an epoxy resin adhesive, and mainly fixes the stator core 11 and the coil winding unit 12 into a whole so that the coil winding is not loosened.

The stator core 11 is in a cylindrical shape, and the plurality of coil winding units 12 are closely arranged on the inner wall surface of the stator core 11 along the circumferential direction, because the core tooth slots of the conventional stator core 11 are not provided, the tooth slot additional torque of the motor is eliminated, the motor achieves the tooth slot-free additional torque, and the running performance of the motor is improved.

Meanwhile, the coil winding units 12 are arranged orderly, so that a large amount of space can be saved, the effective sectional area of a coil wire is increased under the same condition, the electric density of a stator winding is reduced, the copper loss of a stator is reduced, and the efficiency of the motor is improved.

The stator iron core 11 is cylindrical, and no tooth part occupies the space of the iron core, so that the effective placing space of the coil winding is increased, the effective sectional area of a winding enameled wire is increased, the electric density of the stator winding is reduced, the efficiency of the motor is improved, and the temperature rise of the motor is reduced.

Referring to fig. 6 and 7, the stator core 11 is formed by laminating and welding annular silicon steel sheets, the silicon steel sheets are punched into single sheets by a stamping process from cold-rolled silicon steel sheets with a thickness of less than 0.5mm, and the stator core 11 is a carrier of magnetic lines of force of the motor. And in the welding process, the inner hole is positioned by using a special welding die, then the two ends of the inner hole are welded after the end surface of the stator core 11 is pressed tightly, and the number of welding seams is determined according to the shape and the size of the stator core 11. The welding can adopt argon arc welding or laser welding and the like.

In some embodiments, referring to fig. 8, the coil winding unit 12 adopts a formed winding, and the wire group is formed by winding an enameled copper wire, pressing the enameled copper wire into a certain shape by using a mold, and fixing the enameled copper wire on the stator core 11 by using a pouring sealant 13; the enameled copper wire can be a round copper wire or a flat copper wire. The coil winding unit 12 has an outer arc surface that is attached to the inner wall surface of the stator core 11, and the outer arc of the coil winding is made substantially the same as the inner hole arc of the stator core 11, which further saves space.

Specifically, the inner cavity of the winding former is made into a shape the same as the shape of the coil winding unit 12, the coil is bound and fixed by a small rope after winding, and then the shape is further shaped by a shaping former and then the coil is soaked in insulating paint for curing.

When the stator is assembled, firstly, the inner surface of the stator core 11 is pasted with insulating paper, then the coil winding unit 12 is fixed on the inner hole of the stator core 11 by glue, and the coil winding unit 12 is positioned by a special tool during assembly so as to ensure uniform distribution of the coil winding unit 12; and finally, carrying out integral encapsulation treatment on the stator.

Referring to fig. 8, a line side L1 is an effective element side of the coil winding unit 12, which is an element of the motor generating an electromagnetic field; the circular arc portions at both ends are the ends of the coil winding unit 12, and serve to connect the two element sides. The height of the wire end of the formed winding form can be very small, and the height of the wire end is about one third of that of a common coil, and even smaller. Referring to fig. 5, the length of the stator core 11 is not less than the length of the coil winding unit 12, and the coil winding unit 12 is integrally disposed in the stator core 11, thereby further reducing the end leakage reactance and improving the motor efficiency.

Because the coil winding units 12 adopt the concentrated winding and formed winding forms, the coil winding units 12 can be arranged in a close order, the height of a wire end can be made very low (as shown in fig. 8), and under the condition that the installation space of the motor is the same, the effective length of the motor, namely the length of the stator core 11 can be increased, according to the relational expression (formula 1) of the output power of the motor and the volume of the motor:

in the formula: p-motor output power

L-effective length of the machine (stator core 11 length)

n-motor speed

C_p-motor constant

From the formula 1, it can be seen that the output power of the motor is in direct proportion to the effective length of the motor, and the motor can output larger power under the condition of the same motor installation space, so that the embodiment of the invention has higher power density.

The wire end of the wire end winding unit in the embodiment of the invention has small height, so the total length of the materials of the winding copper wire is also short, and according to a calculation formula (formula 2) of the resistance: the length of the winding copper wire is in direct proportion to the resistance value of the phase resistor, the length L of the copper wire is short, and the phase resistor R is small. According to the calculation formula (formula 3) of the copper loss of the motor, the copper loss (P) of the winding_{Copper loss}) Proportional to phase resistance R, small phase resistance R, copper loss P_{Copper loss}And is also small. According to the calculation formula (formula 4) of the motor efficiency, the motor efficiency eta and the winding copper loss P_{Copper loss}Inversely proportional to the copper loss P_{Copper loss}And when the motor efficiency eta is small, the motor efficiency eta is large.

R-winding phase resistance

Rho-resistivity of copper wire

L-copper wire length per phase winding

Cross sectional area of S-winding copper wire

P_{Copper loss}＝mI²R--------------(3)

P_{Copper loss}Copper loss of the winding

Phase I-current

R-winding phase resistance

Eta-motor efficiency

∑P_{Decrease in the thickness of the steel}Sum of various losses of the electric machine

Input power of P-motor

P1-output power of motor

The coil winding unit 12 of the embodiment of the invention adopts the formed winding, and the arrangement of the coils is neat and compact, so that the occupied space is smaller than that of the conventional bulk winding, and the effective sectional area of the enameled copper wire used by the coil winding of the embodiment of the invention can be increased under the same condition. According to the formulas 2, 3 and 4, as the effective sectional area S of the winding enameled copper wire is large, the phase resistance R is small, and the copper loss P is small_{Copper loss}And decreases accordingly, so that the motor efficiency η increases.

The coil winding unit 12 of the embodiment of the present invention has a small height of the end of the wire, so the length L of the end of the half-turn coil_pIs small according to the end leakage reactance X_pIs (formula 5), X_pAnd L_pProportional ratio, L_pMinor rule X_pAnd is also small. Coil end leakage reactance X_pIs the reactance of the leakage field, X, corresponding to the end turn-chain_pThe reduction shows that the utilization rate of the magnetic flux of the motor is high, the input power P of the motor can be reduced under the same condition, and according to the formula 4, the efficiency eta of the motor is improved when the input power P is reduced under the condition that the output power P1 of the motor is not changed.

X_p＝m2πf2pL_p--------------(5)

Number of phases of m-motor

f-motor input frequency

p-number of motor pole pairs

X_p-coil end leakage reactance

L_pEnd length of half turn coil

The coil winding unit 12 of the embodiment of the invention is integrally arranged in the stator core 11, thus partial end leakage reactance can be converted into effective magnetic flux, the utilization rate of the magnetic flux is further improved, the input power is further reduced under the condition of certain output power, and the efficiency eta is also improved.

Referring to fig. 9-11, the rotor assembly 2 includes a rotor core 21 and magnetic steel, the magnetic steel is connected to the rotor core 21, the magnetic steel includes magnetic steel N and magnetic steel S, the magnetic steel N and the magnetic steel S are alternately distributed along the circumferential direction of the rotor core 21, the magnetic steel N and the magnetic steel S generate rotor magnetic flux, and the coil winding generates stator magnetomotive force; the rotor magnetic flux and the stator magnetomotive force are relatively static but have phase difference, when a multi-phase winding with certain spatial difference angle is switched on with multi-phase current with the same time difference angle, the rotating stator magnetomotive force is generated, and the rotor magnetic flux and the stator rotating magnetomotive force interact to generate electromagnetic torque.

The magnetic steel further comprises first transition magnetic steel F, see fig. 9 and fig. 11, the first transition magnetic steel F is located between the adjacent magnetic steel N and the adjacent magnetic steel S, the magnetizing direction of the first transition magnetic steel F is consistent with the direction in which the magnetic force line passes through the first transition magnetic steel F, so that the magnetic force line of the magnetic field passes through the first transition magnetic steel F, the magnetic force line passing through the yoke part of the rotor core 21 is reduced, the magnetic pressure drop of the yoke part of the rotor core 21 is reduced, the magnetic loss is also reduced due to the reduction of the magnetic pressure drop, the input power of the motor can be reduced under the same condition, the magnetic steel can be known from formula 4, and the efficiency of the motor is also improved. The magnetic force lines passing through the rotor core 21 are greatly reduced, so that the magnetic flux density of the yoke part of the rotor core 21 is reduced, and the temperature rise of the motor is reduced; the low temperature of the motor also improves various performance indexes of the motor. The first transition magnetic steel F is added in the above way, so that the efficiency and the power density of the motor can be effectively improved.

The magnetic steel is embedded in a surface-mounted or embedded manner. Referring to fig. 9 and 12, in the surface-mount structure, the outer circumferential surface of the rotor core 21 is provided with a plurality of first magnetic steel slots 22, and the magnetic steel N, the magnetic steel S, and the first transition magnetic steel F are surface-mounted in the first magnetic steel slots 22. Referring to fig. 11 and 13, in the embedded structure, a plurality of second magnetic steel slots 23 are axially formed in the rotor core 21, and the magnetic steel N, the magnetic steel S, and the first transition magnetic steel F are inserted into the second magnetic steel slots 23.

The rotor core 21 may be formed by stamping a cold-rolled silicon steel sheet made of a high magnetic permeability material, and then riveting the stamped sheet. The rotor core 21 may be machined from high-quality low-carbon steel. The rotor assembly 2 is a rotating element of an electric machine and an actuating element for converting electric energy into mechanical energy.

In some embodiments, referring to fig. 9, 11, 12, and 13, a plurality of third magnetic steel slots 24 are formed in a yoke portion of the rotor core 21 along a circumferential direction, a second transition magnetic steel F1 magnetized in a normal direction is disposed in the third magnetic steel slots 24, and a magnetizing direction of the second transition magnetic steel F1 is consistent with a direction of magnetic lines of force passing through the yoke portion of the rotor core 21. Because the third magnetic steel slot 24 is made of permanent magnet and is filled with strong magnetism in a specified direction, the magnetizing direction of the third magnetic steel slot is consistent with the direction of magnetic lines of force passing through the yoke part of the rotor core 21, the magnetic resistance of the magnetized magnetic steel is much smaller than that of the rotor core 21 made of silicon steel sheet or low carbon steel, so that when the magnetic force passes through the third magnetic steel slot 24, the magnetic pressure drop is much smaller than that of the rotor core 21, the magnetic loss is much smaller, according to the related discussion, the efficiency of the motor can be effectively improved, the temperature rise of the motor can be reduced, and the power density of the motor can be improved.

The second transition magnetic steel F1 is tile-shaped, and a plurality of second transition magnetic steels F1 are distributed on the same circumference. The second transition magnetic steel F1 may also be in a zigzag shape, and the second transition magnetic steel F1 is distributed along the circumferential direction of the rotor core 21.

The magnetic steel N and the magnetic steel S are axially divided into a plurality of sections, and the magnetic steel N and the magnetic steel S are axially overlapped in a segmented mode, as shown in fig. 10, so that the eddy current loss of the magnetic steel can be reduced, the temperature rise of the motor is reduced, and the performance of the motor is improved.

In the description herein, references to the description of the term "example," "an embodiment," or "some embodiments," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The invention is not limited to the above embodiments, and those skilled in the art can make equivalent modifications or substitutions without departing from the spirit of the invention, and such equivalent modifications or substitutions are included in the scope of the claims of the present application.

Claims

1. A stator assembly, comprising:

a stator core having a cylindrical shape;

the coil winding comprises a plurality of coil winding units, wherein the coil winding units are tightly arranged on the inner wall surface of a stator core along the circumferential direction, the coil winding units are encapsulated by potting adhesive and form an integral assembly with the stator core, the coil winding units define a rotor space inside the stator core, the coil winding units adopt formed windings, each coil winding unit comprises two element edges, the two element edges are connected through arc parts at two ends, the arc parts are wire ends of the coil winding units, and the length of the stator core is not less than that of the coil winding units.

2. The stator assembly according to claim 1, wherein the coil winding unit has an outer arc surface that is fitted to an inner wall surface of the stator core.

3. The stator assembly of claim 1, wherein the stator core is formed by laminating and welding annular silicon steel sheets.

4. An electric machine, comprising:

a stator assembly according to any of claims 1-3;

a rotor assembly disposed in the rotor space.

5. The electric machine of claim 4, wherein the rotor assembly comprises:

a rotor core;

6. The motor of claim 5, wherein a plurality of first magnetic steel slots are formed in the outer peripheral surface of the rotor core, and the magnetic steel N, the magnetic steel S and the first transition magnetic steel are attached to the first magnetic steel slots.

7. The motor of claim 5, wherein a plurality of second magnetic steel slots are axially formed in the rotor core, and the magnetic steel N, the magnetic steel S and the first transition magnetic steel are inserted into the second magnetic steel slots.

8. The motor of claim 5, wherein a plurality of third magnetic steel slots are formed in a yoke portion of the rotor core along a circumferential direction, a second transition magnetic steel which is magnetized in a normal direction is arranged in each third magnetic steel slot, and a magnetizing direction of each second transition magnetic steel is consistent with a direction of magnetic lines of force passing through the yoke portion of the rotor core.

9. The electric machine of claim 8, wherein the second transition magnetic steel is tile-shaped, and a plurality of the second transition magnetic steels are distributed on the same circumference.

10. The electric machine of claim 5, wherein said magnetic steels N and S are axially divided into segments.