JP2015154582A - Stator for three-phase rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stator for a three-phase rotary electric machine which can be produced at low cost by decreasing the number of components with a coil arrangement where a coil pitch is a full-pitch and a higher harmonic wave component of induction electromotive force is reduced.SOLUTION: The stator for the three-phase rotary electric machine includes: a wavy wound armature coil; a plurality of slots 13 each accommodating a plurality of coil pieces 12 of the armature coil; and a plurality of coil pieces 12 each having a coil pitch equal to a magnetic pole pitch. In every other slot 13, the plurality of coil pieces 12 are accommodated in such a manner that currents flowing in n-th layer and (n+1)th layer coil pieces 12 ((n) is a positive integer) have a phase difference of 2/3 πrad, that all the currents flowing in odd-numbered layers of coil pieces 12 have the same phase and that all the currents flowing in even-numbered layers of coil piece 12 have the same phase. Thus, the stator for the three-phase rotary electric machine can be produced at low cost by reducing the number of components in the coil arrangement where the coil pitch is the full-pitch and the higher harmonic wave component of induction electromotive force is reduced.

Description

  The present invention relates to a stator for a three-phase rotating electrical machine having an effect of reducing harmonic components of induced electromotive force.

  As a method of reducing the harmonic components (mainly fifth order and seventh order) of the induced electromotive force generated in the rotating electric machine and making the electromotive force waveform close to a sine wave, the coil pitch of the coil piece inserted into the slot of the armature winding Is a short-pitch winding with an interval shorter than the magnetic pole pitch.

  Further, the winding of the armature winding typically includes a coil inserted in a slot shifted in the circumferential direction, and a coil inserted in a slot shifted by two magnetic pole pitches in parallel with coil pieces inserted in parallel. There is a wave winding in which the pieces are connected in series. Generally, in short-pitch winding, the slot into which the armature winding is inserted is divided into two layers (outer layer, inner layer), and the armature winding on the stator inner layer side Two-layer lap winding is used in which a coil piece is wound over a coil piece of an armature winding on the stator outer layer side over a predetermined pitch τ (τ <magnetic pole pitch).

  For example, if an armature winding made of a flat conductor described in Patent Document 1 below is used, one coil piece of the armature winding is placed on the stator inner layer side, and the other coil piece is placed on the stator outer layer side. It is possible to apply a short-pitch winding.

  Incidentally, FIG. 4 is a cross-sectional view showing a region corresponding to one magnetic pole pair (a region in the circumferential direction) of the stator of the rotating electrical machine. A stator of a rotating electric machine includes a stator core 11 and an armature winding. In addition, the figure shows the coil piece 12 of the armature winding.

  The stator core 11 is provided with a plurality of slots 13, and a plurality of coil pieces 12 are accommodated in each slot 13. In the stator of the rotating electrical machine shown in FIG. 4, as an example, the number of poles is 8, the number of slots 13 is 48 (the number of slots per phase per pole = 2), and the number of coil pieces 12 accommodated in each slot 13 is 8 ( 8 layers).

  In FIG. 4, slot numbers (1), (2),..., (12) are assigned to the slots 13 in the circumferential direction. Further, as shown in the drawing, the coil pieces 12 of a plurality of layers accommodated in one slot 13 are formed as a first layer,..., An eighth layer from the stator outer diameter side to the stator inner diameter side. Yes.

  FIG. 5 is a winding layout diagram of one magnetic pole of a stator of a three-phase (U-phase, V-phase, W-phase) rotating electrical machine that has been subjected to short-pitch winding by two-layer lap winding, and slot numbers in the horizontal arrow direction (1), (2),..., (12) are indicated, and layer numbers 1, 2,..., 8 indicating the positions of the respective coil pieces 12 are indicated in the downward arrow direction. Layer numbers 1 to 4 are outer layers, and layer numbers 5 to 8 are inner layers. 5 corresponds to the cross-sectional view of FIG. 4, and a 3/4 region (slot numbers (13) to (48)) not shown is a 1/4 region (not shown) (slot number (13) to (48)). The target of the rotation period is slot numbers (1) to (12). In other words, if the winding arrangement in the ¼ region shown in the drawing is one cycle, the winding arrangement in which the one cycle repeats in the ¾ region not shown is obtained.

  When short-ply winding is performed by two-layer lap winding as a conventional technique, as shown in FIG. 5, the coil piece 12 on the stator inner layer side of the slot number (1) is moved to the coil piece 12 on the stator outer layer side of the slot number (6). Similarly, the coil piece 12 on the stator inner layer side with slot number (2) forms a U-phase coil with the coil piece 12 on the stator outer layer side with slot number (7). That is, the coil pitch of the short-pitch winding is layer numbers 1-6, 2-7,..., And the pitch is narrowed by one slot with respect to the magnetic pole pitch.

  On the other hand, in the wave winding, a full-pitch winding whose coil pitch is equal to the magnetic pole pitch is generally adopted. In general, all-volume windings tend to generate harmonic components in the electromotive force waveform.

  FIG. 3 shows a winding arrangement for one magnetic pole of a stator of a three-phase rotating electric machine in which all the coil turns of the coil pieces inserted into the slots of the armature winding are all wound with the same pitch as the magnetic pole pitch. It is a figure and each number in the said figure and the period of winding arrangement | positioning are the same as that of FIG. As shown in FIG. 3, all the coil pieces 12 housed in one slot 13 have the same phase as shown in FIG. 3, and each coil piece 12 of slot number (1) has each slot number (7). A U-phase coil is formed on each coil piece 12. Similarly, each coil piece 12 with slot number (2) forms a U-phase coil with each coil piece 12 on slot number (8). As described above, the coil pitch in all the windings is layer numbers 1-7, 2-8,..., Which is equal to the magnetic pole pitch of all the windings.

JP 2009-195006 A JP 2010-178622 A

  In the above-mentioned Patent Document 1, since it is a short-pitch winding by two-layer lap winding, harmonics are not easily generated, but lap winding in which coils are connected in parallel is unsuitable for making the terminal voltage high. There is a problem of limited use.

  Further, Patent Document 2 discloses a technique for improving the electromotive force waveform of a wave winding by reducing all fifth and seventh harmonic components, with all coil pitches being full-pitch winding. However, for example, when the number of coil pieces / the number of slots = 6 (FIG. 5 of Patent Document 2), three or more types of windings are required, which increases the number of parts and increases the cost.

  Therefore, in the present invention, the coil pieces are connected by wave winding, the coil pitch is full-pitch winding, and the harmonic arrangement of the induced electromotive force is reduced. An object of the present invention is to provide a stator for a three-phase rotating electrical machine that can be manufactured at low cost by reducing the number of parts.

The stator of the three-phase rotating electrical machine according to the first invention for solving the above-described problems is,
A wave-wound armature winding;
A plurality of slots each containing a plurality of coil pieces of the armature winding;
A stator of a three-phase rotating electrical machine comprising a plurality of coil pieces each having a coil pitch equal to a magnetic pole pitch,
In each of the alternate slots, the plurality of coil pieces have a phase difference of 2 / 3π rad in the current flowing through the n-th and n + 1-th coil pieces, where n is a positive integer, and The currents flowing through the odd-numbered coil pieces are all in phase, and the currents flowing through the even-numbered coil pieces are all in phase.

The stator of the three-phase rotating electrical machine according to the second invention for solving the above-described problems is
In the stator of the three-phase rotating electrical machine according to the first invention,
The number of coil pieces per slot is 2 m, where m is a positive integer.

  According to the stator of the rotating electrical machine of the present invention, the coil pieces are connected by wave winding, the coil pitch is full-pitch winding, the harmonic arrangement of the induced electromotive force is reduced, and one type of coil piece is used. Can be manufactured at low cost by reducing the number of points.

It is a winding arrangement | positioning figure for 1 magnetic pole of the stator of the three-phase rotary electric machine which concerns on Example 1 of this invention. It is the graph which compared the induced electromotive force of the stator of the three-phase rotary electric machine which concerns on Example 1 of this invention, the stator of a short-pitch winding, and the stator of a full-pitch winding. The vertical axis represents the induced electromotive force (pu), and the horizontal axis represents the electrical angle [deg]. FIG. 5 is a winding layout diagram for one magnetic pole of a stator of a three-phase rotating electric machine, in which all coil turns of all coil pieces inserted into slots of the armature winding are equal to the magnetic pole pitch. It is sectional drawing showing the area | region for 1 magnetic pole pair of the stator of a rotary electric machine. FIG. 5 is a winding layout diagram using one magnetic pole of a stator of a three-phase rotating electrical machine that has been subjected to short-pitch winding by two-layer lap winding.

  Hereinafter, a stator of a three-phase rotating electrical machine according to the present invention will be described with reference to the drawings by way of examples.

[Example 1]
The configuration of the stator of the three-phase rotating electrical machine according to the first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a winding arrangement diagram for one magnetic pole of a stator of a three-phase rotating electrical machine according to Embodiment 1 of the present invention. Each number in the drawing and the period of the winding arrangement are the same as those in FIG. is there. In the following, similarly to the stator of FIG. 4 described above, the number of coil pieces 12 accommodated in each slot 13 is 8 and the number of slots 13 is 48 (number of slots per phase per pole = 2). It is assumed that there are eight.

  In the stator winding arrangement of the three-phase rotating electrical machine according to the first embodiment of the present invention, the phase of the coil piece 12 is all + U in the slot number (1) of FIG. ), N (n is a positive integer; the same shall apply hereinafter). The coil pieces 12 in the layer and the (n + 1) th layer are arranged so that the phases of + U and −W are alternated.

  That is, in each of the alternate slots 13, the plurality of coil pieces 12 have a phase difference of 2 / 3π rad in the current flowing through the n-th layer and the (n + 1) -th layer coil pieces 12, and the odd-numbered coils The currents flowing through the pieces 12 are all in phase, and the currents flowing through the even-numbered coil pieces 12 are all in phase.

  The winding arrangement of the stator of the three-phase rotating electrical machine according to the first embodiment of the present invention is the same as that of FIG. 1 except that the first coil piece 12 with slot number (1) is the second layer with slot number (7). It crosses over the coil piece 12 and is wound in a wave shape around the third coil piece 12 having a slot number (13) (not shown; periodically corresponds to the slot number (1)). Form.

  Similarly, the first layer coil piece 12 with the slot number (2) crosses over to the second layer coil piece 12 with the slot number (8), and from there the slot number (14) (not shown. A third phase coil piece 12 (corresponding to number (2)) is wound in a wave shape to form a W-phase coil.

  That is, the coil pitch in the stator of the three-phase rotating electrical machine according to the first embodiment of the present invention is the layer numbers 1-7, 2-8,.

  The winding arrangement of the stator of the three-phase rotating electrical machine according to the first embodiment of the present invention is such that, for example, in slot number (2), a total of four + U coil pieces 12 and a total of -W coil pieces 12 are arranged. ing. On the other hand, the winding arrangement (FIG. 5) of the stator of the three-phase rotating electrical machine, which has been subjected to the short-pitch winding by the conventional two-layer winding, has a total of four + U coil pieces 12 (stator number) in the slot number (2). Inner layer side) and -W coil pieces 12 are arranged in total (stator outer layer side).

  Therefore, the number of coil pieces 12 accommodated in each slot 13 is equal to the winding arrangement of the stator of the three-phase rotating electric machine that has been subjected to full-pitch winding by the wave winding according to the first embodiment of the present invention, and the conventional two-layer overlap. It is the same as the winding arrangement of the stator of the three-phase rotating electric machine that has been subjected to short-pitch winding.

  FIG. 2 is a diagram illustrating all the nodes having a phase difference of 2 / 3π rad when the coil pieces wound in every other slot by the wave winding according to the first embodiment of the present invention flow through the nth layer and the n + 1th layer. A stator of a three-phase rotating electric machine configured with a winding arrangement with windings, a stator of a three-phase rotating electric machine configured with a short-pitch winding by two-phase lap winding, and wound in a slot with wave windings FIG. 6 is a graph comparing the induced electromotive force waveforms calculated by magnetic field analysis for each of the stators of a three-phase rotating electric machine configured with a winding arrangement in which all current windings having the same phase are applied to the coil pieces to be mounted. . The vertical axis represents the induced electromotive force (pu), the horizontal axis represents the electrical angle [deg], and A is wound in every other slot by wave winding according to the first embodiment of the present invention. A stator of a three-phase rotating electrical machine having a winding arrangement in which the coil pieces have a full-pitch winding in which the current flowing through the nth layer and the n + 1th layer has a phase difference of 2 / 3π rad, B is a short due to two-phase lap winding A stator of a three-phase rotating electric machine configured with a winding arrangement with a joint winding, C is a winding arrangement with all the windings of the same phase of the current flowing through a coil piece wound in a slot by wave winding It is the stator of the comprised three-phase rotary electric machine.

  As shown in FIG. 2, the current flowing through the nth layer and the (n + 1) th layer of the coil pieces wound in every other slot by the wave winding according to the first embodiment of the present invention of A is about 2 / 3π rad. Stator of a three-phase rotating electrical machine configured with a winding arrangement with a full-pitch winding having a phase difference, and a stator of a three-phase rotating electrical machine configured with a winding arrangement with a short-pitch winding by two-phase overlapping winding of B The electromotive force waveforms of are equal. That is, by the winding arrangement of the stator of the three-phase rotating electrical machine according to the first embodiment of the present invention, an electromotive force waveform characteristic equivalent to that of a short-pitch winding by two-layer lap winding is obtained while being full-pitch winding by wave winding. Can do.

  In addition, the phase (U, V, W) of each armature winding is determined by the connection processing at the start and end of winding of each armature winding, and the stator of the three-phase rotating electrical machine according to Embodiment 1 of the present invention In the winding arrangement, since the magnetic pole pitch and the coil pitch are the same, it is possible to make a full-pitch winding as shown in FIG.

  In the above description, the stator of the three-phase rotating electrical machine according to the first embodiment of the present invention has 8 poles and 48 slots 13 (number of slots per phase per pole = 2) and is accommodated in each slot 13. Although the number of coil pieces 12 is assumed to be eight, the present embodiment is not limited to this.

  Although the stator of the three-phase rotating electrical machine according to the first embodiment of the present invention has been described above, the stator of the three-phase rotating electrical machine according to the first embodiment of the present invention includes a wave armature winding and an electric A stator of a three-phase rotating electrical machine comprising a plurality of slots 13 for accommodating a plurality of coil pieces 12 of a child winding, and a plurality of the coil pieces each having a coil pitch equal to a magnetic pole pitch, In each of the slots 13, the plurality of coil pieces 12 have a phase difference of 2 / 3π rad in the n-th and n + 1-th layer coil pieces 12, where n is a positive integer, The currents flowing through the pieces 12 are all in phase, and the currents flowing through the even-numbered coil pieces 12 are all in phase. In this way, the harmonic component of the induced electromotive force can be reduced and the electromotive force waveform closer to a sine wave can be obtained with the entire winding by wave winding.

  In the stator of the three-phase rotating electrical machine according to the first embodiment of the present invention, the magnetic pole pitch and the coil pitch of the coil piece 12 may be equal. In this way, a stator with a full-pitch winding as shown in FIG. 3 can be obtained by connecting the coil end ends.

  Furthermore, in the stator of the three-phase rotating electrical machine according to the first embodiment of the present invention, the number of coil pieces 12 per slot 13 may be 2 m, where m is a positive integer. Thus, if the number of coil pieces 12 / the number of slots 13 is an even number, only one type of coil piece of the necessary armature winding is required, and the cost can be reduced by reducing the number of parts.

  The present invention is suitable as a stator for a three-phase rotating electrical machine.

11 Stator core 12 Coil piece 13 (of armature winding) 13 Slot

Claims (2)

A wave-wound armature winding;
A plurality of slots each containing a plurality of coil pieces of the armature winding;
A stator of a three-phase rotating electrical machine comprising a plurality of coil pieces each having a coil pitch equal to a magnetic pole pitch,
In each of the alternate slots, the plurality of coil pieces have a phase difference of 2 / 3π rad in the current flowing through the n-th and n + 1-th coil pieces, where n is a positive integer, and A stator for a three-phase rotating electrical machine, wherein the currents flowing through the odd-numbered coil pieces are all in phase, and the currents flowing through the even-numbered coil pieces are all in phase. .   The stator of the three-phase rotating electrical machine according to claim 1, wherein the number of the coil pieces per slot is 2m, where m is a positive integer.

Images