JPS6387161A - Rotary electric machine - Google Patents

Abstract

PURPOSE:To reduce cogging torque, by using the armature of a salient pole type, and by providing a field system section with auxiliary grooves. CONSTITUTION:A rotary electric machine is composed of a back yoke 1, the field system section 2 of a permanent magnet, the armature core 4 of a salient pole type, and a threephase armature winding 5 wound up on the core. In this case, a section confronted with the armature core 4 in the field system section 2 is provided with auxiliary grooves 7a-7b in the direction of the axis of a rotational center 6. Then, magnetic flux generated from the field system section 2, bypassing field boundary sections 3a-3b and the auxiliary grooves 7a-7b, most of which are high magnetic reluctance, is absorbed by the armature core 4, and the state of the magnetic nonuniformity of the field system section is changed. Accordingly, harmonic component in relation to cogging torque is reduced, and the cogging torque can be reduced.

Description

[Detailed description of the invention] [Field of industrial application] Q) The invention is an electric motor that can obtain a rotational output from a power supply and a rotational output from a Regarding rotary electric machines that can obtain output, I am particularly interested in improving the structure of the field section.

[Conventional technology]

A conventional rotary city machine of this type is shown in Japanese Patent Publication No. 58-42707, but it is called Ql or A1.

FIG. 4 is a schematic sectional view showing an example of a conventional Q) rotating electrical machine. In figure Cζ, (1) is Bar Quyoke, (2)
+, t2 permanent magnet forming pole Q) field part, (3 &) (
8b) is the boundary of the field part (2), (4) is the salient pole type armature core, and (5) is the 8-phase iir machine edge winding, field part (2
) The armature cores (4) are opposed to each other with a minute gap in between, and one of the armature cores (4) is rotatable relative to the other about the rotation center (6).

When considering the rotating electric machine in Figure 4 as an electric motor, the armature winding (5
) can be sequentially energized to obtain continuous rotating torque through electromagnetic interaction between the field part (2) and Q). Think of it as a generator, and by rotating the field part (2), which is the rotor, from the outside, you can get an AC output from the armature winding (5).

In general, when a salient pole type armature core and a field permanent magnet are used, magnetically non-uniform areas occur, and cogging torque is generated due to interaction between the two, which has the disadvantage of being ineffective.

Cogging torque is related to the magnetic inhomogeneity of the field a part and the wI machine core, and when both have periodicity, the frequency is the harmonic component + IM composite component 1 frequency that exists in common to both. .

Figure 5 (1) shows the periodicity of the magnetic field in the field part (2) of the rotating electric machine in Figure 4 for one rotation, and the fundamental harmonic component has the number of magnetic poles of 2 as the order. This is the second harmonic base and includes the fourth, sixth, etc. harmonic components (
The component that repeats once per revolution is considered the first harmonic base, and the rest can be treated in the same way. ).

111 Machine core (4) l Magnetic non-uniformity is caused by permeance fluctuations in the salient pole part, and the fundamental harmonic component is the 3rd harmonic bottom, 6th, 9th... ...etc. high pitch ff
i minutes (including. Therefore, the cogging torque is t boundary a part (2
) and W edge core (4) 1ζ occurs when the OI harmonic components match (match), and in this example) ζ, the 6th, 12th,
...The harmonic component of @ is mainly generated; ζ, as shown in Fig. 5 (2)
shows the cogging torque for one rotation.

[Problems that the invention does not solve]

As mentioned above, when using a salient pole type 0)B' armature core and using a permanent magnet for the field, there are complaints that unevenness occurs and cogging torque is generated.

The purpose of the Q1 invention is to significantly reduce the cogging torque by having a salient pole type armature and to obtain a single rotation 7 machine.

[First means for solving the problem] The market switching machine according to the present invention has the ability to form P magnetic poles (where P is 2 or more and J+!!1), and has a field magnetic section that is capable of forming Q+ magnetic poles. Q1
The armature winding is provided with a wI armature having a groove for the wound winding and a salient pole, the field part is configured to rotate one of the armatures with respect to the other 1ζ, and the field An auxiliary groove is provided in the magnetic part at a position facing the electric machine, and the order of the fundamental harmonic component of the magnetic non-uniformity of the field part having the auxiliary groove is np (where n is an integer of 2 or more). If the fundamental harmonic component of the magnetic non-uniformity due to the grooves for the winding of the armature is the mth order (where m is an integer), then np is a common multiple of m or m is npO + common multiple r (It is constructed so that it does not occur.)

[Effect]

In this invention Cζ, an auxiliary groove is provided in the field part so that the harmonic e component can be adjusted to a higher order.

Figure 1 shows a schematic cross section, and (1) to (6) in the figure are the fourth
Figure Q) Same as the conventional example, +7a C (7b) is w! in the field part (2). The auxiliary groove is provided in the thruster iron core (the 4-piece rotation part is provided with a T-shaped auxiliary groove, and is provided in the axial direction of the rotation center (6).

Most of the magnetic flux emitted from the field part (2) comes from the field boundary part (3a c (3h) and the auxiliary groove trh) where the magnetic resistance is high.

Avoid (7h) and absorb it by τ'N, s-core (4)G. Q) Result field part (2) t7'! The state of atmospheric heterogeneity changes. Embodiment 1 of the invention shown in FIG.
In this case, auxiliary ff1 (7a) and (7J) are provided at the position that equally divides the interval between the field boundaries (aac (3h)).
aJ, <7a).

The entire tah (7b)0' is arranged at approximately equal intervals with respect to the center of rotation (6).

Therefore, the basic component of the 8th period of magnetic inhomogeneity in the field part (2) is the 4th harmonic component, the 8th order, the 12th order, etc.
On the other hand, the armature core (4
) has the same harmonic components as the conventional example shown in FIG.
As a result, harmonic components such as the 12th harmonic, the 24th harmonic, etc. of the main 1ζ are generated when the coking torque is lost, and the order of the fundamental harmonic component is the 6th harmonic in the OI conventional example shown in Figure 4. In contrast, in this example, the 12th order is twice as high-order, and the 6th, 18th, etc. harmonic components disappear or decrease. There is. FIG. 2 shows the periodicity of the magnetic field of the field section (2) of the invention and the cogging torque for one rotation.

Generally, the magnitude of each component of cogging torque is
) 6 city machine iron core (4) t7i with τ is proportional to mlζ of the size of the corresponding component, further! ? :The size of the 6th fraction decreases as it becomes 6 fractions, whereas the 12th fraction becomes considerably smaller.

Therefore, by providing the auxiliary groove according to the present invention, it is possible to reduce the harmonic components related to cogging torque from fζ, and furthermore, it is possible to significantly reduce the cogging torque by increasing the basic harmonic components to a higher order. .

Q) What is the basic mv component of the time salient pole type 7 palm + 71 magnetic inhomogeneity? : When you die, the mth and 2mth.

Contains &'4 wave components such as 8th m order...
Field part without auxiliary grooves 0) The basic harmonic component of magnetic inhomogeneity is the 9th order, where the number of poles is P. Providing auxiliary grooves will improve the fundamental harmonic component of the field part. The fundamental harmonic components of cogging torque are m and n.
The least common multiple of p.

In addition, it is necessary to arrange the total number of auxiliary grooves and field boundaries (corresponding to np) so that the number of armature salient poles (corresponding to m) does not become a common multiple of λ, or so that m does not become a common multiple of np. There is.

Well, the entire auxiliary groove at the field boundary part is equiangularly spaced or almost equiangularly r from the center of rotation! By arranging them at i intervals, the cogging torque reduction effect can be further enhanced.

In the first embodiment of the invention shown in FIG.
When the rotor is the rotor t and the field part is @ hiko, the effect is the same even if the relationship is reversed.

M7: Black auxiliary groove (7aj (7N (70
By increasing the numbers J(7d)(7e)(7f), the cogging torque Q) fundamental harmonic component +71st order can be further increased and the magnitude of Qr can be significantly reduced.

〔Effect of the invention〕

As described above, according to the present invention, a conventional salient pole type armature is used, and an auxiliary groove is provided in the field part.
Cogging torque can be effectively reduced at low cost.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view according to an embodiment of the present invention, FIG. 2 is a waveform diagram showing magnetic field distribution and cogging torque according to the present invention, and FIG. 3 is a schematic cross-sectional view according to another embodiment of the present invention.
Fig. 4 is a conventional schematic cross-sectional view, and Fig. 5 is a conventional magnetic field distribution t.
FIG. 3 is a waveform diagram showing cogging torque. In the figure, (1) is the bulk yoke, (2) is the field part, (
3a9Cab) is the field magnetic pole boundary, (4) is the armature, (
5) is the armature winding, (6) C is the center of rotation, <78) <7b
)t7C)<7d) (7e) (7f) are auxiliary grooves. In addition, in the figures, the same reference numerals indicate the same parts, and squares indicate corresponding parts.

Claims (2)

[Claims] (1) Equipped with a field part forming P magnetic poles (where P is an integer of 2 or more), and an armature having winding grooves and salient poles in which multi-phase armature windings are wound. , one of the field part and the armature is rotated relative to the other;
An auxiliary groove is provided in the field part at a position facing the armature, and the order of the fundamental harmonic component of the magnetic non-uniformity of the field part having the auxiliary groove is np (where n is 2 or more). np
1. A rotating electric machine characterized in that it is configured such that np is not a common multiple of m or m is not a common multiple of np. (2) The rotation according to claim 1, wherein each boundary part of the field magnetic pole and each auxiliary groove are arranged at equal angular intervals or approximately equal angular intervals with respect to the center of rotation. Electric machine.