CN111697717B - Motor stator punching sheet and motor - Google Patents

Abstract

The application provides a motor stator punching sheet, including interconnect and a plurality of towards the piece unit that the structure is the same, it is a plurality of can enclose towards the piece unit and synthesize motor stator punching sheet, every towards the piece unit all has the dead slot, the dead slot is including setting up the notch towards the stator tooth of piece unit is in with the setting towards the groove shoulder towards the shoulder of piece unit, the notch with the groove shoulder is linked together. The motor stator punching sheet adopts the mode that the yoke part of the punching sheet unit is far away from the stator teeth to arrange the notch and the stator teeth are arranged with the groove shoulders which extend along the radial direction of the punching sheet unit, and the notch and the groove shoulders are combined, so that the problems that in the prior art, the universality is poor and the size is difficult to control only by adopting the notch of the stator teeth, and the tooth space torque of a motor is effectively inhibited.

Description

Motor stator punching sheet and motor

Technical Field

The invention relates to the technical field of driving devices, in particular to a motor stator punching sheet and a motor.

Background

The starting characteristics of the motor mainly comprise two performance parameters of starting current and starting torque, and the two performance parameters are limited by cogging torque.

The existing motor stator punching structure is mostly a round bottom or flat bottom pear-shaped groove, in a motor, especially in a surface type rotor direct current brushless motor with low torque and high rotating speed, the stator punching has poor anti-interference performance to the cogging torque, and is influenced by the cogging torque in the starting process of the motor, so that a larger starting torque is obtained by increasing an excitation magnetic field, the starting current is increased, the magnetic circuit is easily saturated, and the power consumption of the motor is increased. And, if the starting current is too big, still easily cause the electric current rush to the control panel chip of motor. In the process of motor variable speed driving, when the torque ripple frequency is consistent with the mechanical resonance frequency of the motor, the harmonic content of the electrode cogging torque is increased, and the electrodes are difficult to obtain good starting characteristics and stable operation.

Therefore, how to suppress the cogging torque of the motor stator is an urgent technical problem to be solved.

Disclosure of Invention

To the problem among the above-mentioned prior art, this application has proposed a motor stator punching and motor for solve above-mentioned technical problem.

In a first aspect, the application provides a motor stator punching sheet, including interconnect and a plurality of towards the piece unit that the structure is the same, it is a plurality of towards the piece unit and can enclose synthetically motor stator punching sheet, every empty slot has all been seted up towards the stator tooth of piece unit, the empty slot is including the notch and the groove shoulder of mutual intercommunication, the notch sets up the alar part of stator tooth, the groove shoulder sets up the shoulder of stator tooth is followed towards the radial extension of piece unit.

The motor stator punching sheet adopts the mode of arranging the notch on the wing part of the stator tooth and the groove shoulder extending along the radial direction of the punching sheet unit on the shoulder part of the stator tooth, combines the notch and the groove shoulder, not only solves the problems of poor universality and difficult size control existing in the end part grooving opening of the stator tooth in the prior art, but also effectively inhibits the tooth space torque of a motor.

In one embodiment according to the first aspect, the notch is symmetrical along its own central axis, thereby avoiding the introduction of new cogging torque harmonics.

In one embodiment according to the first aspect, the notch is configured in a semi-circular shape, the semi-circular notch being effective to optimize the air gap coupling strength.

In one embodiment according to the first aspect, the diameter of the notch is 2/3 of the width of the notch, and the junction of the notch and the wing adopts fillet transition, so that the effective value of the cogging torque can be suppressed to the maximum extent, and the fourier harmonic component of the cogging torque is distributed in a reasonable range.

In one embodiment according to the first aspect, the groove shoulder comprises a groove body located between the notch and the groove bottom, and the groove bottom is disposed at an end of the shoulder remote from the wing.

In one embodiment according to the first aspect, the side walls of the channel body are configured as outwardly convex arcs.

In one embodiment according to the first aspect, the groove bottom is configured as a semi-circular structure.

In one embodiment according to the first aspect, the empty groove is configured as an inclined groove, and the maximum width of the shoulder part on the left side of the groove body is larger than that of the shoulder part on the right side of the groove body, so that the high-order harmonic of the cogging torque Fourier is suppressed, the coupling strength of an air gap is increased, and the skin effect of a stamped magnetic circuit is optimized.

In a second aspect, the present application provides a motor stator comprising the motor stator lamination according to the first aspect.

In a third aspect, the present application provides an electric machine comprising a stator lamination of an electric machine according to the first aspect.

Compared with the prior art, the method has the following advantages:

1) the motor stator punching sheet adopts the mode of arranging the notch on the wing part of the stator tooth and the groove shoulder extending along the radial direction of the punching sheet unit on the shoulder part of the stator tooth, combines the notch and the groove shoulder, not only solves the problems of poor universality and difficult size control existing in the stator tooth notch in the prior art, but also effectively inhibits the tooth space torque of a motor.

2) The notch is designed to be symmetrical along its own central axis, thereby avoiding the introduction of new cogging torque harmonics.

3) The notch is formed in a semicircular shape, and the semicircular notch can effectively optimize the air gap coupling strength.

4) The diameter of the notch is designed to be 2/3 of the width of the notch, so that the effective value of the cogging torque can be inhibited to the greatest extent, and the Fourier harmonic component distribution of the cogging torque is ensured in a reasonable range.

5) The hollow groove is constructed into a chute, the side wall of the groove body is constructed into an outward convex arc shape, the maximum width of the shoulder part on the left side of the groove body is designed to be larger than that of the shoulder part on the right side of the groove body, and the top value of a periodic magnetic flux density waveform excited in an air gap is optimized, so that the Fourier high-order harmonic of the cogging torque is inhibited, the coupling strength of the air gap is increased, and the skin effect of a magnetic circuit of a punching sheet is optimized.

The features mentioned above can be combined in various suitable ways or replaced by equivalent features as long as the object of the invention is achieved.

Drawings

The invention will be described in more detail hereinafter on the basis of embodiments and with reference to the accompanying drawings. Wherein:

fig. 1 shows a schematic view of a chain type punching sheet before being assembled according to the present application.

Fig. 2 shows a schematic structural diagram of the motor stator punching sheet after the chain type punching sheet shown in fig. 1 is enclosed.

Fig. 3 shows an enlarged structure of the empty slot in fig. 2.

Fig. 4 shows an enlarged structural view of the empty tank of fig. 2.

Fig. 5 shows a schematic structural diagram of a rotor assembled according to the simulation of the stator punching of the motor shown in fig. 2.

Fig. 6 shows a distribution diagram of a cogging torque of a conventional motor stator lamination.

Fig. 7 shows a profile of cogging torque using stator laminations of an electric machine according to the present application.

Fig. 8 shows a cogging torque harmonic component diagram of a conventional motor stator lamination.

Fig. 9 shows a plot of the cogging torque harmonic components using stator laminations of an electric machine according to the present application.

Fig. 10 shows a waveform diagram of an air gap magnetic field of a conventional motor stator lamination.

Fig. 11 shows a waveform of an air gap field using a stator lamination of an electric machine according to the present application.

Fig. 12 shows a flux linkage waveform diagram of a stator lamination of a conventional motor.

Fig. 13 shows a flux linkage waveform diagram using a stator lamination of a motor according to the present application.

In the drawings, like parts are provided with like reference numerals. The drawings are not to scale.

Detailed Description

The invention will be further explained with reference to the drawings.

Fig. 1 shows a schematic structural diagram of a chain type punching sheet before being assembled according to the present application, and the chain type punching sheet shown in fig. 1 is enclosed to form a motor stator punching sheet 10 shown in fig. 2. The chain is towards piece including a plurality of towards piece units 1 that interconnect and structure are the same, a plurality of towards piece units 1 can enclose synthetic motor stator towards piece 10 (see fig. 2), every towards piece unit 1 all has stator tooth 100 and yoke portion 13, every stator tooth 100 all has slot 2, slot 2 includes notch 21 (see fig. 4) and groove shoulder 22, notch 21 sets up at the alar part 11 of stator tooth 100 (keeping away from the one end of yoke portion 13 promptly, see fig. 2), groove shoulder 22 sets up shoulder 12 at stator tooth 100, groove shoulder 22 is along the radial extension towards piece unit 1, notch 21 is linked together with groove shoulder 22.

In the embodiment shown in fig. 1, the number of the punching units is 12, the included angle between adjacent punching units 1 is 30 °, and the angle of each punching unit 1 is 30 °. It can be understood that the number of the punching units 1 can be changed, and the included angle between adjacent punching units 1 and the angle of each punching unit 1 are correspondingly adjusted, so that the requirement that stator punching can be formed by enclosing is met.

Based on the following principle: the notches 21 are formed in the wing portions of the stator teeth 100, so that the number of cycles of a cogging torque fundamental wave can be increased, a new cogging torque can be assisted to compensate for the original cogging torque, and the amplitude of the total cogging torque can be reduced. In the prior art, most methods for inhibiting the cogging torque adopt a mode of forming notches on stator teeth, but the mode is greatly limited by the structures of the groove width and the groove type, and if the size of the groove width is not properly selected, the cogging torque cannot be inhibited, so that the limitation is large and the effect is not obvious. In the invention, the notch 21 and the groove shoulder 22 are combined by forming the notch 21 on the wing part 11 of the stator tooth 100 and forming the groove shoulder 22 on the shoulder part 12 of the stator tooth 100, so that the cogging torque of the motor is effectively inhibited.

The structure of the empty groove 2 is shown in fig. 4. Preferably, the notch 21 is symmetrical along its own central axis, thereby avoiding the introduction of new cogging torque harmonics.

In the embodiment shown in fig. 4, the notch 21 is preferably configured in a semi-circular shape, and the semi-circular notch 21 is effective to optimize the air gap coupling strength. After the empty groove 2 is completely arranged, there is no clear boundary between the notch 21 and the groove body 22, and the notch 21 and the groove body 22 form the integral empty groove 2, as shown in fig. 3.

More preferably, the diameter of the notch 21 is designed to be 2/3 of the width of the notch 1, and the junction of the notch 21 and the wing 11 is rounded, as shown in fig. 3, the width of the notch 21 is represented by L1, the diameter of the notch 21 is 2/3L1, and the rounded corner of the junction of the notch 21 and the end 11 is represented by R2. The design can inhibit the effective value of the cogging torque to the maximum extent and ensure that the Fourier harmonic component of the cogging torque is distributed in a reasonable range.

As shown in fig. 3 and 4, the slot shoulder 22 includes a slot body 221 and a slot bottom 222, the slot body 221 is disposed between the slot opening 21 and the slot bottom 222, and the slot bottom 222 is disposed at one end of the shoulder 12 near the yoke 13. More preferably, the groove bottom 222 is configured in a semicircular configuration. From the viewpoint of simplification, the width L3 of the slot bottom 222 is designed to be smaller than the width of the slot opening L1, the bottom wall of the slot bottom 222 does not exceed the bottom wall of the winding slot 200 (see fig. 2), the position where the slot bottom 222 contacts with the shoulder 12 adopts fillet transition, and the fillet radius is R1.

Considering that the number of slots is increased twice as much as the original number of times of the cogging torque and the number of times of the cogging torque is simultaneously increased twice in the process of opening the empty slots 2, in order to reduce harmonics caused by the number of times of the cogging torque, it is preferable that the empty slots 2 are configured as inclined slots, and it is preferable that the side walls of the slot bodies 221 are configured as outwardly convex arcs, as shown in fig. 3 and 4. The maximum width of the shoulder 12 (the shoulder of the punching unit 1) on the left side of the slot body 221 (the slot body width is L5, and the length is L2) is greater than the maximum width of the shoulder 12 (the shoulder of the punching unit 1) on the right side of the slot body 221, namely the widths of L6 and L4 marked in fig. 3 and fig. 4, wherein L6 is greater than L4, so that the empty slot 2 forms a skewed slot with the slot bottom 222 biased to the right side, the top value of the periodic magnetic flux density waveform of air gap collective excitation is optimized, the cogging torque fourier higher order harmonics are suppressed, the coupling strength of the air gap is increased, and the stamped magnetic circuit skin effect is optimized.

It should be noted that the chute 2 is symmetrical about its own central axis.

The motor stator punching sheet can be applied to the motor stator, so that all the advantages of the motor stator punching sheet are achieved.

Specifically, the chain is punched the piece and is enclosed to close processing in order to form the stator punching according to this application, then with a plurality of stator punching stromatolite settings in order to form stator core, later to stator core carry out the package and mould the processing, form the package and mould the stator. And then, plastic is completely poured into the empty groove 2, so that the residual tension threshold is enhanced, and the hidden danger that stator teeth are distorted in the winding process is avoided. And after the stator core is wrapped with plastic and wound, the stator core is subjected to rounding process treatment, and an upper rotor and a preferable damping rotor are assembled and then tested to verify the starting characteristic of the motor.

Referring to fig. 5, a schematic diagram of a motor stator and rotor simulation assembly according to the present application is shown, in the simulation structure, an air gap is 0.5mm, a stator winding adopts a centralized fractional slot wiring mode, and a rotor 20 adopts a symmetric distribution mode of 8-pole ferrite surface mount. And setting simulated boundary conditions, operation step length and additional materials, wherein the parameters are model preprocessing before finite element simulation. Wherein, the boundary condition is as follows: specifying infinity as the magnetic field vector zero, the running step length: for finite element simulation model runtime step length, add materials: the iron core material is silicon steel material, the magnetic shoe is ferrite, and the winding is copper.

After the above parameters are set, simulation results of flux linkage, air gap magnetic field, cogging torque, harmonic component and the like are analyzed, and the analysis results are specifically shown in fig. 6-13, which respectively show a cogging torque distribution diagram, a cogging torque harmonic component diagram, an air gap magnetic field waveform diagram and a flux linkage waveform diagram obtained by testing the existing motor (only a stator tooth is provided with a notch) and the motor of the present application.

In summary, the present application has the following advantages: 1) the motor stator punching sheet adopts the mode of arranging the notch at the end part of the stator tooth and the groove shoulder at the shoulder part of the stator tooth, combines the notch and the groove shoulder, solves the problems of poor universality and difficult size control existing in the stator tooth notch in the prior art, and effectively inhibits the cogging torque of a motor. 2) The notch is designed to be symmetrical along its own central axis, thereby avoiding the introduction of new cogging torque harmonics. 3) The notch is formed in a semicircular shape, and the semicircular notch can effectively optimize the air gap coupling strength. 4) The diameter of the notch is designed to be 2/3 of the width of the notch, so that the effective value of the cogging torque can be inhibited to the greatest extent, and the Fourier harmonic component distribution of the cogging torque is ensured in a reasonable range. 5) The hollow groove is constructed into a chute, the side wall of the groove body is constructed into an outward convex arc shape, the maximum width of the shoulder part on the left side of the groove body is designed to be larger than that of the shoulder part on the right side of the groove body, and the top value of a periodic magnetic flux density waveform excited in an air gap is optimized, so that the Fourier high-order harmonic of the cogging torque is inhibited, the coupling strength of the air gap is increased, and the skin effect of a magnetic circuit of a punching sheet is optimized.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "bottom", "top", "front", "rear", "inner", "outer", "left", "right", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the present invention.

Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that features described in different dependent claims and herein may be combined in ways different from those described in the original claims. It is also to be understood that features described in connection with individual embodiments may be used in other described embodiments.

Claims (9)

1. A motor stator punching sheet is characterized by comprising a plurality of punching sheet units which are connected with each other and have the same structure, wherein the punching sheet units can be enclosed to form the motor stator punching sheet, each punching sheet unit is provided with a stator tooth and a yoke part, one end, away from the yoke part, of each stator tooth is a wing part of each stator tooth, the part, between the yoke part and the wing part of each stator tooth, of each stator tooth is a shoulder part of each stator tooth, each stator tooth of each punching sheet unit is provided with a hollow groove, each hollow groove divides each stator tooth into two parts along the circumferential direction, each hollow groove comprises a notch and a groove shoulder which are mutually communicated, each notch is arranged on the side of the wing part of each stator tooth, and each groove shoulder is arranged on the shoulder part of each stator tooth and extends along the radial direction of each punching sheet; the notch structure is semi-circular, and two alar parts all have partial contour line to be located semi-circular notch, the lateral wall structure of groove shoulder is the arc of evagination.

2. The electric machine stator lamination as recited in claim 1, wherein the slot is symmetrical along a central axis thereof.

3. The motor stator punching sheet according to claim 1, wherein a joint of the semicircular notch and the wing part adopts a fillet transition, the semicircular notch and the fillet form a hollow notch, and the diameter of the semicircular notch is 2/3 of the width of the hollow notch.

4. The electric machine stator lamination of any one of claims 1-3, wherein the groove shoulder comprises a groove body and a groove bottom, the groove body is located between the groove opening and the groove bottom, and the groove bottom is disposed at an end of the shoulder portion away from the wing portion.

5. The motor stator lamination as recited in claim 4, wherein the side wall of the slot body is configured as a convex arc.

6. The electric machine stator lamination as recited in claim 4, wherein the slot bottom is configured as a semi-circular structure.

7. The electric machine stator lamination as recited in claim 5, wherein the empty slot is configured as an oblique slot, and a maximum width of the shoulder of the stator tooth on the left side of the slot body is greater than a maximum width of the shoulder of the stator tooth on the right side of the slot body.

8. An electric machine stator, characterized in that it comprises an electric machine stator lamination according to any one of claims 1-7.

9. An electric machine, characterized in that it comprises a stator lamination of an electric machine according to claim 8.

Images