JP2003319575A - Stator core for synchronous machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve efficiency of a synchronous machine by suppressing the flow of ineffective flux of magnetic induction in a teeth part and suppressing generation of the iron loss due to the ineffective flux of magnetic induction, in a stator core of the synchronous machine. <P>SOLUTION: In the structure of a stator consisting of teeth made of steel sheets stacked and a yoke, one or a plurality of slits are formed in a lengthwise direction of a teeth part of the steel plate to suppress generation of a flow of ineffective flux of magnetic induction in the teeth part. It is preferable that a slit width is 1/10 or less a teeth width with a slit length 1/2 or more a teeth length and less than the teeth length. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator core of a synchronous machine, and more particularly to a structure of teeth forming a stator core of the synchronous machine.

[0002]

2. Description of the Related Art For example, as shown in FIG. 3 (a), a stator iron core constituting a synchronous motor is generally provided with a substantially cylindrical yoke portion 1 formed of laminated steel plates and a circumferential portion thereof. It is formed by a plurality of tooth portions 2 arranged at intervals and an armature winding 3 wound around the tooth portion. The tip end faces of the plurality of tooth portions 2 are disclosed, for example, in Japanese Patent Laid-Open No. 6-22508. As disclosed in (FIG. 1), it is often formed in an arc surface corresponding to the rotation surface of the rotor 4 arranged at the center of the stator. In a synchronous machine having a stator iron core composed of the tooth portions 2 having such tip surfaces, as shown in FIG.
The effective magnetic flux A flowing from the tooth portion 2 to the other tooth portion 2 via the yoke portion 1 depending on the rotation angle and the field distribution of
In addition to o, a reactive magnetic flux Ax that flows in the teeth 2 in parallel with the tip surfaces of the teeth and does not flow in the other teeth causes iron loss to increase and the efficiency of the synchronous machine to decrease. is there.

[0003]

SUMMARY OF THE INVENTION According to the present invention, in a stator core of a synchronous machine, the generation of a reactive magnetic flux in the teeth portion is suppressed and the iron loss due to the reactive magnetic flux is suppressed to improve the efficiency of the synchronous machine. A stator core is provided.

[0004]

Means for Solving the Problems The present invention includes the following (1) to
The main point is (4). (1). A stator core of a synchronous machine, comprising: a stator core including teeth and a yoke formed by laminating steel plates, wherein one or more slits are formed in a longitudinal direction of a tooth portion of the steel plate. (2). In (1), the slit width is 1 of the teeth width.
A stator core of a synchronous machine characterized by being / 10 or less. (3). In (1) or (2), the slit iron length is 1/2 or more of the tooth length, and is less than or equal to the tooth length. (4). In any one of (1) to (3), the stator core of a synchronous machine is characterized in that the positions of the slits are different between adjacent steel plates in the stacking direction. (5). In any one of (1) to (4), a stator iron core of a synchronous machine, wherein the inside of the slit is filled with a non-magnetic insulating resin.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The stator iron core of the present invention is applied as a stator iron core of a synchronous machine, and has a substantially cylindrical yoke portion formed by laminating steel sheets and equidistantly in the circumferential direction. It consists of a plurality of teeth arranged and armature windings wound around the teeth, and one or more slits are formed in the longitudinal direction for each teeth of the steel plate, and the teeth are invalid. By suppressing the generation of the flow of magnetic flux and suppressing the generation of iron loss due to the ineffective magnetic flux, it contributes to improving the efficiency of the synchronous machine.

As a condition for forming the slit formed in the tooth portion, the width of the slit is preferably 1/10 or less of the tooth width. As for the width of the slit, it is preferable that the magnetic resistance of the magnetic path from one tooth tip that bypasses the slit and bypasses the slit to the other tooth tip is greater than the magnetic resistance of the magnetic path from the tooth tip to the yoke portion. Therefore, it is preferable that it is larger than the minimum slit width bm represented by the following formula (1). bm = a × (dc) / c / μ ------ (1) where bm: minimum slit width (mm) a: teeth width (mm) d: teeth length (mm) c : Slit length (mm) μ: Relative permeability of steel sheet The relative permeability of the steel sheet used for the iron core is several thousand or more, the tooth width a is in the range of several mm to several tens of mm, and the tooth length d is If the slit length c is twice or less, the minimum slit width may be several microns, which is 1/10 of the thickness of the steel plate.
It is about 0, which is below the limit of normal machining. Also, it is better that the slot width is wider in terms of magnetic resistance,
Since the effective width of the teeth becomes narrower and the magnetic flux density of the effective magnetic flux passing through the teeth increases, the iron loss increases. Therefore, it is preferably 1/10 or less of the width of the teeth. The length of the slit is 1/2 or more of the tooth length,
It is preferably equal to or less than the tooth length. If the length of the slit is less than 1/2 of the tooth length, it is not possible to sufficiently suppress the generation of the flow of the invalid magnetic flux in the tooth portion. However, if the length of the slit exceeds the length of the tooth, the distance between the slit and the outer diameter of the yoke becomes narrower than the width of the yoke, which may hinder the flow of effective magnetic flux in the yoke. Moreover, the rigidity of the iron core is reduced, which is not preferable. It is not an absolute requirement that the slits formed in each steel plate be aligned in the stacking direction, and the slit positions may be shifted between the adjacent steel plates in the stacking direction. In this case, although the slits pass through in each laminated steel plate unit, even if the slits are not penetrated in the tooth portion unit, the generation of the reactive magnetic flux can be suppressed appropriately. Further, the slit does not have to be a void, and filling with a non-magnetic insulating resin is effective in suppressing the rigidity reduction of the teeth due to the slit formation.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the stator core of the present invention is applied to a stator of a synchronous electric motor in which a permanent magnet is arranged on a rotor will be described with reference to FIG. In FIG. 1 (a),
Reference numeral 1 denotes a yoke portion, which is formed by punching a plurality of steel plates s laminated together with a plurality of teeth portions 2 circumferentially provided on the inner peripheral side thereof. The tooth portion 2 is for winding the armature winding 4, and has a slit 5 formed in the width center portion. The slit 5 has a width b of 1/10 or less of the width a of the tooth portion 2 and a length of approximately 2/3 of the length d of the tooth portion 2.
As shown in (b), it penetrates in the laminating direction of the steel plates. For example, as shown in FIG. 1 (c), a slit 5a penetrating in the laminating direction is formed for each steel plate s, and adjacent slits are formed in the laminating direction. The forming positions may be shifted between the steel plates s to be formed so that the teeth portion 2 does not penetrate in the stacking direction of the steel plates s.

When the stator core having the slits 5 or 5a formed in the tooth portion 2 is used as in this embodiment, the generation of the ineffective magnetic flux flow Ax occurs at the tip portion of the tooth portion 2 as shown in FIG. It is possible to suppress the generation of iron loss due to the reactive magnetic flux, and flow from the tooth portion 2 to the other tooth portion 2 via the yoke portion 1 due to the rotation angle and magnetic field distribution of the rotor arranged in the center of the stator. It is possible to increase the flow of the effective magnetic flux Ao and improve the motor efficiency. The present invention is not limited to the above embodiment. For example, in the embodiment, the present invention is applied as a stator iron core of a synchronous electric motor in which permanent magnets are arranged on the rotor, but it is also applicable as a stator iron core of other types of electric motors and generators. Regarding the cross-sectional shape and arrangement of armature windings, the shape and structure of teeth and yokes, and the conditions for forming slits (size, number of threads, etc.), the claims should be made according to the type and capacity of the motor or generator. There are changes within the range of satisfaction.

[0009]

In the stator structure of the present invention, the slits are formed in the teeth portion, so that the generation of the reactive magnetic flux in the tooth portion 2 is suppressed and the iron loss caused by the reactive magnetic flux is suppressed. The efficiency can be improved.

[Brief description of drawings]

FIG. 1 (a) is a partially cutaway front view showing an example of a stator core according to an embodiment of the present invention, (b) and (c).
The figure is an Aa-Ab arrow partial cutaway cross-section explanatory drawing of the (a) figure which shows the slit formation example (2 examples) of a teeth part.

FIG. 2 is a partially cutaway front view showing a flow of magnetic flux according to an embodiment of the present invention.

FIG. 3 (a) is a front partial explanatory view showing an example of a conventional general stator iron core, and FIG. 3 (b) is a partially cutaway front view showing the flow of magnetic flux in the example of the stator iron core shown in FIG. 3 (a). Explanatory drawing.

[Explanation of symbols]

1 York 2 Teeth 3 Armature winding 4 Rotor 5, 5a slit s steel plate

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takeaki Wakisaka             20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel shares             Company Technology Development Division F-term (reference) 5H002 AA02 AA03 AB01 AE07

Claims (5)

[Claims] 1. A stator iron core of a synchronous machine, comprising: a stator iron core including teeth and a yoke formed by laminating steel plates, wherein one or more slits are formed in a longitudinal direction of a tooth portion of the steel plate. . 2. The stator core of a synchronous machine according to claim 1, wherein the slit width is 1/10 or less of the tooth width. 3. The stator core of a synchronous machine according to claim 1, wherein the slit length is 1/2 or more of the tooth length and is equal to or less than the tooth length. 4. The stator core of a synchronous machine according to claim 1, wherein the positions of the slits are different between adjacent steel plates in the stacking direction. 5. The stator iron core of a synchronous machine according to claim 1, wherein the inside of the slit is filled with a non-magnetic insulating resin.