JP3722126B2 - Reluctance motor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a reluctance motor.
[0002]
[Prior art]
Conventionally, a rotor body in which a permanent magnet is embedded in a rotor body made of a high permeability material such as iron is known.
[0003]
FIG. 6 shows a rotor with a permanent magnet having a two-layer structure developed by the present inventors in order to effectively use the reluctance torque. (JP-A-8-331783)
The rotor 1 according to the prior invention has a rotor shaft 2 at the center, and an iron rotor core 3 is embedded with four sets of permanent magnets 4a and 4b arranged at intervals of two layers per pole in the radial direction of the rotor. Thus, each set of permanent magnets 4a and 4b is arranged adjacent to each other so that the S poles and the N poles are alternately arranged, and both are formed in a circular arc shape convex in the centripetal direction of the rotor. The iron rotor core 3 is configured by laminating a large number of perforated core sheets. The iron rotor core 3 is laminated by aligning the positions of the holes, and the above-described arc-shaped permanent magnet is inserted and embedded.
[0004]
[Patent Document 1]
JP-A-8-331783
[Problems to be solved by the invention]
In the configuration of the above prior invention, the number of man-hours for assembling the rotor is the smallest and can be manufactured at low cost, but the slit portion provided in the rotor is configured straight and parallel to the rotor shaft, so the positional relationship with the stator However, the cogging torque fluctuation during the rotation of the rotor is large.
[0006]
As an example, FIG. 7 shows the fluctuation result of torque ripple by magnetic field analysis in the configuration of the prior invention. As is clear from this data, a large torque fluctuation of about 80% is shown.
[0007]
[Means for Solving the Problems]
In order to solve the above-mentioned problems of the prior invention, the invention according to the present application is the same for a permanent magnet embedded type reluctance motor in which a permanent magnet is embedded in the rotor core in the axial direction. The rotor cores are embedded in a plurality of rotor cores divided in the axial direction, and the plurality of rotor core finished products are shifted in the rotor rotation direction and integrally formed in the axial direction. More specifically, in a reluctance motor in which a permanent magnet is embedded in the axial direction inside a rotor of a reluctance motor,
The rotor is composed of a plurality of rotor core finished products divided in the axial direction, and a rotor shaft into which the plurality of rotor core finished products are inserted as a unit,
The permanent magnet is embedded in a plurality of layers at intervals in the radial direction of the rotor core finished product for each pole of the rotor core finished product, and the shape of the permanent magnet is an arc shape convex in the centripetal direction of the rotor Further, the magnetic poles of the permanent magnets are arranged so that the S poles and the N poles alternate for each pole,
Due to the positional relationship of the rotational position of the stator teeth of the reluctance motor and the permanent magnet of the rotor,
Of each of the rotor core finished products, when the permanent magnet of one rotor core finished product and the teeth of the stator face each other and the amount of magnetic flux flowing from the stator side to the rotor side in the one rotor core finished product is small The positional relationship between the slot of the other rotor core finished product and the teeth of the stator is shifted from the position where the permanent magnet of the other rotor core finished product and the teeth of the stator are opposed to each other. The amount of magnetic flux flowing from the stator side to the rotor side is large,
At the next time point, the magnetic flux flowing from the stator side to the rotor side in the one rotor core finished product is shifted from the position where the permanent magnet of the one rotor core finished product and the teeth of the stator face each other. The amount of magnetic flux flowing from the stator side to the rotor side in the other rotor core finished product is small, and the permanent magnet of the other rotor core finished product is opposed to the stator teeth at this time,
In this way, each of the rotor core finished products is a reluctance motor configured integrally in the axial direction by shifting in the rotational direction so that the amount of magnetic flux flowing from the stator side to the entire rotor side is averaged . Furthermore, in the above-described reluctance motor, the reluctance motor is a reluctance motor having a four-pole rotor core in which a plurality of arc-shaped permanent magnets are embedded with two layers per pole.
Further, in any one of the above reluctance motors, the rotor is a reluctance motor having two rotor core finished products.
Furthermore, in any one of the above-described reluctance motors, the rotor is a reluctance motor having three rotor core finished products.
[0008]
According to this invention, the position of the slit portion provided in the rotor and the position of the teeth of the stator do not coincide with each other at the same time, so that cogging is reduced and a reluctance motor having good characteristics with less torque ripple can be obtained.
[0009]
The invention according to the present application is a reluctance type synchronous motor having a rotor provided with a plurality of slits, wherein the rotor includes a plurality of rotor core finished products, and each rotor core finished product has the slit position in the rotation direction. They are shifted and configured integrally in the axial direction.
[0010]
According to this invention, the position of the slit portion provided in the rotor and the position of the teeth of the stator do not coincide with each other at the same time, so that cogging is reduced and a reluctance motor having good characteristics with less torque ripple can be obtained.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
In order to solve the above-mentioned problems, the present invention is a reluctance motor having a rotor configured by shifting a plurality of rotor core finished products in the rotational direction.
[0012]
In the reluctance motor having permanent magnets, the permanent magnets were obtained by dividing the permanent magnets into a plurality of pieces in the rotor axial direction and embedding the permanent magnets in the rotor core sheet laminated according to the axial length of each permanent magnet. A plurality of finished rotor cores are shifted in the rotational direction to form a single body to obtain a rotor. In addition, a reluctance motor that does not have a permanent magnet has the same configuration as that described above just by having no permanent magnet.
[0013]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
[0014]
(Example 1)
As shown in FIG. 1, the permanent magnets 4 a and 4 b embedded in the rotor 1 are divided into two in the axial direction, and the rotor core sheet is matched to the axial length of the divided permanent magnets 4 a and 4 b. To obtain the rotor core 3. Completed rotor cores 3a and 3b are obtained in which the permanent magnets 4a and 4b divided into the laminated rotor core 3 are respectively embedded and integrated.
[0015]
The two rotor core finished products 3a and 3b are joined while being shifted in the rotational direction, and the rotor shaft 2 is inserted by means such as press fitting to obtain the rotor 1.
[0016]
FIG. 3 shows an explanatory diagram of the positional relationship between the rotor and stator in the rotor core finished product 3a. FIG. 4 is an explanatory view of the positional relationship of the rotor and the stator in the rotational direction in the rotor core finished product 3b. 3 and 4 show the positional relationship with the teeth and slots on the stator side at a rotational position where the rotor 1 in which the rotor core finished products 3a and 3b are integrally formed is located.
[0017]
As shown in FIG. 3 on the rotor core finished product 3a side, when the permanent magnets 4a and / or 4b match the position of the stator teeth 6, the magnetic resistance increases and the magnetic flux 8 decreases. On the other hand, since the position of the stator teeth 6 and the permanent magnets 4a and / or 4b are shifted from each other on the rotor core finished product 3b side as shown in FIG. 4, the magnetic resistance decreases and the magnetic flux 8 increases.
[0018]
3 and FIG. 4, the amount of magnetic flux flowing from the stator side to the rotor side is small on the rotor core finished product 3a side and large on the rotor core finished product 3b side, and the rotor 1 as a whole is averaged. Will be. Although not shown, the amount of magnetic flux flowing from the stator side to the rotor side at the next time point is large on the rotor core finished product 3a side and small on the rotor core finished product 3b side, and the rotor 1 as a whole is still averaged. The
[0019]
Since the change in the amount of magnetic flux becomes cogging torque, a reluctance motor with small cogging torque can be obtained by the configuration of the present invention.
[0020]
FIG. 5 shows a result of torque ripple variation by magnetic field analysis in the configuration of the present invention. As is apparent from this data, the torque fluctuation is about 35%, which is a significant improvement over the conventional example shown in FIG.
[0021]
In the above-described embodiment, the rotor has been described as integrally configured with two rotor core finished products. However, the rotor may be configured with three or more rotor core completed products integrated. If three or more rotor core finished products are shifted in the same rotation direction, or half of the rotor core toward the rotor center is shifted in the same rotation direction and the other half is shifted in the opposite direction, the cogging torque is further reduced and the torque fluctuation Becomes smaller.
[0022]
(Example 2)
As shown in FIG. 2, a rotor core finished product 3a obtained by laminating a core sheet provided with a plurality of arc-shaped slits and a rotor core finished product 3b obtained in the same manner are joined while being shifted in the rotational direction. Then, the rotor shaft 2 is inserted by means such as press fitting to obtain the rotor 1.
[0023]
With this configuration, since the permanent magnets 4a and 4b in the first embodiment are merely replaced with the slit 5, a reluctance motor having a small cogging torque can be obtained as in the first embodiment.
[0024]
In the above-described embodiment, the rotor has been described in which two rotor core finished products are integrally configured. However, a rotor in which three or more rotor core finished products are integrally configured may be used. If three or more rotor core finished products are shifted in the same rotation direction, or half of the rotor core toward the rotor center is shifted in the same rotation direction and the other half is shifted in the opposite direction, the cogging torque is further reduced and the torque fluctuation Becomes smaller.
[0025]
【The invention's effect】
According to the present invention, by making a reluctance motor having a rotor integrally configured by shifting a plurality of rotor core finished products respectively in the rotation direction, a reluctance motor having a small cogging torque and a small torque ripple during rotation is obtained. Good characteristics with reduced noise and vibration during motor rotation can be obtained.
[Brief description of the drawings]
FIG. 1 is a perspective view of a rotor according to an embodiment of the present invention. FIG. 2 is a perspective view of a rotor according to another embodiment of the present invention. FIG. 5 is a diagram for explaining the operation of the embodiment of the present invention. FIG. 5 is a characteristic diagram by magnetic field analysis of the embodiment of the present invention. FIG. 6 is a perspective view of a conventional rotor. Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Rotor 2 Rotor shaft 3 Rotor core 3a, 3b Completed rotor core 4 Permanent magnet 5 Slit 6 Stator tooth 7 Slot 8 Magnetic flux β Deviation in rotation direction of rotor core

Claims (4)

In the reluctance motor in which the permanent magnet is embedded in the axial direction inside the rotor of the reluctance motor,
The rotor is composed of a plurality of rotor core finished products divided in the axial direction, and a rotor shaft into which the plurality of rotor core finished products are inserted as a unit,
The permanent magnet is embedded in a plurality of layers at intervals in the radial direction of the rotor core finished product for each pole of the rotor core finished product, and the shape of the permanent magnet is an arc shape convex in the centripetal direction of the rotor Further, the magnetic poles of the permanent magnets are arranged so that the S poles and the N poles alternate for each pole,
Due to the positional relationship of the rotational position of the stator teeth of the reluctance motor and the permanent magnet of the rotor,
Of each of the rotor core finished products, when the permanent magnet of one rotor core finished product and the teeth of the stator face each other and the amount of magnetic flux flowing from the stator side to the rotor side in the one rotor core finished product is small The positional relationship between the slot of the other rotor core finished product and the teeth of the stator is shifted from the position where the permanent magnet of the other rotor core finished product and the teeth of the stator are opposed to each other. The amount of magnetic flux flowing from the stator side to the rotor side is large,
At the next time point, the magnetic flux flowing from the stator side to the rotor side in the one rotor core finished product is shifted from the position where the permanent magnet of the one rotor core finished product and the teeth of the stator face each other. The amount of magnetic flux flowing from the stator side to the rotor side in the other rotor core finished product is small, and the permanent magnet of the other rotor core finished product is opposed to the stator teeth at this time,
Thus, a reluctance motor configured integrally the rotor core finished products each being offset in rotational direction in the axial direction so that the amount of magnetic flux flowing across the rotor side from the stator side are averaged, further A reluctance motor in which the rotor core is a four-pole rotor core, and a plurality of arc-shaped permanent magnets are embedded at intervals in two layers per pole.   The reluctance motor according to claim 1 or 2, wherein the rotor has two rotor core finished products.   The reluctance motor according to claim 1, wherein the rotor has three rotor core finished products.   The reluctance motor according to claim 1, wherein the plurality of layers of permanent magnets are replaced with a plurality of layers of slits.

Images