Armatures and rotating electric machines

Abstract

To provide an armature with a high torque improvement effect due to a magnetic wedge. [Solution] The armature includes an armature core having a yoke portion, a plurality of teeth each protruding radially from the yoke portion, and slots formed between adjacent teeth, a coil housed in the slot for exciting the armature core, and a magnetic wedge containing a magnetic material and positioned radially toward one side of the coil in the slot facing the coil. The magnetic wedge has a first body portion extending axially of the armature core and in contact with a first surface of the teeth, a second body portion extending axially of the armature core and in contact with a second surface opposite the first surface of the teeth, and a connecting portion connecting the first body portion and the second body portion in the circumferential direction. A gap extending axially of the armature core is formed between the first body portion and the second body portion within the slot.

Description

[Technical Field]

[0001] This invention relates to an armature and a rotating electric machine. [Background technology]

[0002] Conventionally, a configuration has been known in which radially extending teeth are formed in a comb-like shape on the armature core of a rotating electric machine, and a pre-formed annular coil is fitted radially into the slots between the teeth. In armatures of this type, an open slot shape is adopted in which the ends of the slots on the armature core are open, so a wedge member is required to prevent the coil from coming out radially from the armature core.

[0003] As an example of the wedge member described above, a magnetic wedge having a permeability close to that of the armature core is sometimes applied to suppress the performance degradation of a rotating electric machine due to the opening of the armature core (for example, Patent Documents 1 and 2). Because magnetic wedges have a higher permeability than non-magnetic wedge members, they contribute to improving torque by reducing the electrical resistance in the magnetic circuit of the rotating electric machine. In addition, magnetic wedges have the effect of reducing torque pulsation and losses in the rotating electric machine by suppressing the slot harmonics of the armature. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Patent No. 6965101 [Patent Document 2] Japanese Patent Publication No. 2019-97329 [Overview of the project] [Problems that the invention aims to solve]

[0005] On the other hand, if a conventional trapezoidal cross-section, solid, plate-shaped magnetic wedge is fitted into the slot of the armature core, the armature core becomes equivalent as a magnetic circuit to a closed-slot shape where the slot ends are closed. While an armature with a closed-slot shape has improved torque compared to the open-slot shape described above, it has lower torque compared to a semi-open slot with salient poles (flanges) that protrude circumferentially formed at the tooth ends. Therefore, there was still room for improvement in the torque improvement effect of the magnetic wedge on the armature.

[0006] The present invention has been made in view of the above circumstances, and provides an armature with a higher torque improvement effect due to a magnetic wedge than conventional armatures. [Means for solving the problem]

[0007] An armature according to one embodiment comprises an armature core having a yoke portion, a plurality of teeth portions extending radially from the yoke portion to one side, and slots formed between adjacent teeth portions, a coil housed in the slots for exciting the armature core, and a magnetic wedge containing a magnetic material and positioned radially to one side of the coil in the slots and facing the coil. The magnetic wedge has a first main body portion extending in the axial direction of the armature core and in contact with the first surface of the teeth portion, a second main body portion extending in the axial direction of the armature core and in contact with a second surface facing the first surface of the teeth portion, and a connecting portion connecting the first main body portion and the second main body portion in the circumferential direction. Within the slots, a gap portion extending in the axial direction of the armature core is formed between the first main body portion and the second main body portion. The connecting portion is Without being placed in a slot Slot to axis one side The first and second main body parts, which are positioned in a protruding location and located within a single slot, are connected in the circumferential direction at a position that overlaps with the slot.

[0008] Ma Furthermore, other embodiments of a rotating electric machine include an armature according to one embodiment described above. [Effects of the Invention]

[0009] According to one aspect, it is possible to provide a rotor having a higher torque improvement effect by a magnetic wedge than in the prior art.

Brief Description of the Drawings

[0010] [Figure 1] It is a figure which shows the cross section of the rotating electrical machine of 1st Embodiment. [Figure 2] It is a partially enlarged view of the stator in the rotating electrical machine of 1st Embodiment. [Figure 3] It is a figure which shows the structural example of the magnetic wedge applied in 1st Embodiment. [Figure 4] It is a partially enlarged view of the stator in the rotating electrical machine of 2nd Embodiment. [Figure 5] It is a figure which shows the structural example of the magnetic wedge applied in 2nd Embodiment. [Figure 6] It is a partially enlarged view of the stator in the rotating electrical machine of 3rd Embodiment. [Figure 7] It is a figure which shows the structural example of the magnetic wedge applied in 3rd Embodiment. [Figure 8] It is a figure which shows the modification of the shape of the magnetic wedge. [Figure 9] It is a figure which shows the magnetic circuits of Comparative Examples 2 and 3 and the Example together with mathematical formulas. [Figure 10] It is a figure which shows the calculated values of torque for each torque load ratio in each motor of Comparative Examples 1 to 3 and the Example.

Modes for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the embodiments, for the sake of easy understanding of the description, structures and elements other than the main part of the present invention will be described in a simplified or omitted manner. Also, in the drawings, the same elements are denoted by the same reference numerals. Note that the shapes, dimensions, etc. of each element shown in the drawings are schematically shown and do not indicate actual shapes, dimensions, etc.

[0012] In the following explanation, the direction parallel to the extension direction of the rotation axis Ax of the rotating electric machine is referred to as the axial direction, the circumferential direction centered on the rotation axis Ax is simply referred to as the circumferential direction, and the radial direction centered on the rotation axis Ax is simply referred to as the radial direction. Furthermore, in the following explanation, "extending in the axial direction" includes not only cases where the extension is strictly in the axial direction, but also cases where the extension is inclined in a direction less than 45° with respect to the axial direction. Furthermore, "extending in the radial direction" includes not only cases where the extension is strictly in the radial direction, i.e., in a direction perpendicular to the axial direction, but also cases where the extension is inclined in a direction less than 45° with respect to the radial direction.

[0013] (First Embodiment) Figure 1 shows a cross-sectional view of the rotating electric machine of the first embodiment in a direction perpendicular to the rotation axis Ax. Figure 2 is a partially enlarged view of the stator of the rotating electric machine of the first embodiment. Figure 3(a) is a front view of the magnetic wedge applied in the first embodiment. Figure 3(b) is a plan view of the magnetic wedge in its mounted state. Figure 3(c) is a front view of the magnetic wedge in its mounted state.

[0014] The rotating electric machine 1 shown in Figure 1 is an inner rotor type motor and has a rotor 2 and a cylindrical stator 3 arranged on the outer circumference of the rotor 2. In Figure 1, the direction of extension of the rotation axis Ax of the rotating electric machine 1 is perpendicular to the plane of the paper.

[0015] The rotor 2 has a shaft 4 fitted along the rotation axis Ax, and the rotor 2 is rotatably supported around the shaft 4 by bearings (not shown). The rotor 2 may be configured as any of the following: a magnet-embedded rotor, a surface-mounted magnet rotor, a squirrel-cage rotor, a wound-type rotor, etc. A stator 3 is also arranged concentrically with the rotor 2, separated by a small air gap.

[0016] The stator 3 is an example of an armature, and houses the rotor 2 in a central space centered on the rotation axis Ax. The stator 3 has a stator core 5, a coil 6, and a magnetic wedge 7.

[0017] The stator core 5 is a component constructed by laminating multiple metal plates, such as electromagnetic steel sheets, in the axial direction. It has a yoke portion 5a that forms a cylindrical shape on the outer circumference and multiple teeth portions 5b that protrude radially inward from the yoke portion 5a. Note that the radially inward side is an example of one side in the radial direction.

[0018] Multiple tooth portions 5b are arranged in a comb-like shape at equal intervals in the circumferential direction of the yoke portion 5a. In addition, slots 5c for housing the coil 6 are formed between adjacent tooth portions 5b in the circumferential direction of the stator core 5.

[0019] Furthermore, grooves 5d for engaging magnetic wedges are formed on both sides of the teeth portion 5b of the stator core 5, near the inner circumference end facing the rotor 2. Each groove 5d is formed in the radial direction of the teeth portion 5b on the inner circumference side of the portion where the coil 6 is housed, and both extend in the axial direction of the stator core 5. In one slot 5c, the grooves 5d formed on adjacent teeth portions 5b are arranged to face each other.

[0020] Coil 6 is constructed by electrically connecting coil segments, for example, in which flat wire is wound in a ring shape. The winding of coil 6 is not limited to flat wire, but may also be round wire or the like.

[0021] Each coil 6 corresponds to one of the U, V, or W phases of the three-phase AC. The coils 6 for each phase are wound around the teeth 5b of the stator 3 with a phase shift in the circumferential direction to excite the stator core 5, and a portion of the winding is housed in the slots 5c. For simplicity, the coils 6 are not shown in Figure 2. The coils 6 provided on the stator 3 may be either concentrated windings or distributed windings.

[0022] In the rotating electric machine 1, the magnetic field of the stator 3 is sequentially switched by controlling the current of the coil 6, which generates an attractive or repulsive force with the magnetic field of the rotor 2. As a result, the rotor 2 rotates around the rotation axis Ax, and the rotating electric machine 1 is driven.

[0023] The magnetic wedges 7 are positioned radially inward from the coil 6 in each slot 5c of the stator core 5, and are members that face the inner circumferential surface of the coil 6 when attached to the stator 3. For example, the magnetic wedges 7 may be fixed to the stator core 5 by varnish (not shown) when the coil 6 is varnished.

[0024] As shown in Figures 3(b) and (c), the magnetic wedge 7 is fitted into the groove 5d of the tooth portion 5b and held by the stator core 5, and serves to prevent the coil 6 from falling out to the inner circumference side of the slot 5c.

[0025] Furthermore, the magnetic wedge 7 contains a magnetic material. As a result, the magnetic wedge 7 has the function of improving the torque of the rotating electric machine 1 by suppressing the magnetic resistance in the magnetic circuit of the rotating electric machine 1, and reducing the leakage magnetic flux entering the coil 6 from the rotor 2, thereby reducing pulsation of the magnetic flux density distribution.

[0026] The material for the magnetic wedge 7 described above can be any material that is known to be applicable to magnetic wedges. For example, the magnetic wedge 7 may be formed by impregnating glass fibers with a magnetic material such as iron powder and epoxy resin. Alternatively, the magnetic material included in the magnetic wedge 7 may be, for example, flattened magnetic metal particles with an amorphous structure exhibiting three-dimensional anisotropy.

[0027] Furthermore, as shown in Figures 3(a) and 3(c), the magnetic wedge 7 of the first embodiment is a thin plate-like member whose front view shape, when viewed from the inner circumference side of the stator 3, is formed in an H shape. The magnetic wedge 7 has a pair of first main body portions 11 and second main body portions 12 extending in the axial direction, and a connecting portion 13.

[0028] The first main body portion 11 of the magnetic wedge 7 contacts the first circumferential surface of the teeth portion 5b when attached to the stator 3. The second main body portion 11 of the magnetic wedge 7 contacts the second surface of the teeth portion 5b (the surface facing the first surface of the teeth portion 5b within the slot 5c) when attached to the stator 3. In the first embodiment, the teeth portion 5b that the first main body portion 11 contacts and the teeth portion 5b that the second main body portion 12 contacts are different teeth portions that are located next to each other.

[0029] As shown in Figures 2 and 3(c), the first main body portion 11 and the second main body portion 12 have axial lengths that are approximately the same as the axial length of the stator core 5. Also, as shown in Figure 3(b), the thickness of the first main body portion 11 and the second main body portion 12 (vertical dimension in Figure 3(b)) is such that it can be fitted into the groove 5d of the teeth portion 5b.

[0030] The connecting portion 13 of the magnetic wedge 7 is formed in the axial middle portion of the first main body portion 11 and the second main body portion 12, and connects the first main body portion 11 and the second main body portion 12 in the width direction (the left-right direction in Figures 3(a) and (c), which corresponds to the circumferential direction of the stator 3). In other words, in the magnetic wedge 7 of the first embodiment, the first main body portion 11 and the second main body portion 12 are connected by a single connecting portion 13 located within the slot 5c.

[0031] Furthermore, in the region of the magnetic wedge 7 excluding the connecting portion 13 in the axial direction, a gap 14 is formed in the magnetic wedge 7 that extends axially between the first main body portion 11 and the second main body portion 12 and penetrates the magnetic wedge 7 in the thickness direction. The axial length of the connecting portion 13 is set to be sufficiently smaller than the axial length of the entire area where the gap 14 is formed in the magnetic wedge 7.

[0032] Because air is present in the gap 14, its magnetic permeability is significantly lower than that of the first main body 11 and the second main body 12. Therefore, in the magnetic wedge 7, the flow of magnetic flux between the first main body 11 and the second main body 12 is obstructed by the gap 14.

[0033] In the first embodiment, by applying a magnetic wedge 7 to the slot 5c of the stator core 5, the stator 3 can be manufactured relatively easily by fitting a pre-formed annular coil segment into the slot 5c from the radial direction, thereby reducing the manufacturing cost of the stator 3. Furthermore, in the stator 3 of the first embodiment, the magnetic wedge 7 can prevent the coil 6 from falling out radially.

[0034] Furthermore, the magnetic wedge 7 in the first embodiment has a first main body portion 11 that extends in the axial direction of the stator core 5 and contacts the first surface of the teeth portion 5b, a second main body portion 12 that extends in the axial direction of the stator core 5 and contacts the second surface facing the first surface of the teeth portion 5b, and a connecting portion 13 that connects the first main body portion 11 and the second main body portion 12 in the circumferential direction. Within the slot 5c, a gap portion 14 is formed between the first main body portion 11 and the second main body portion 12, extending in the axial direction of the stator core 5. In the stator 3 of the first embodiment, salient poles in the circumferential direction are formed by the first main body portion 11 and the second main body portion 12 on the inner circumference side of the slot 5c, and an axially extending gap portion 14 is formed between the first main body portion 11 and the second main body portion 12 of the magnetic wedge 7. As a result, the magnetic circuit of the stator 3 of the first embodiment approaches a semi-open slot shape, and the torque improvement effect of the stator 3 is improved compared to when a conventional closed slot shape magnetic wedge is applied.

[0035] In the first embodiment described above, an example was given in which one connecting portion 13 of the magnetic wedge 7 is provided within the slot 5c. However, a configuration in which multiple connecting portions 13 are provided within the slot 5c at intervals in the axial direction is also possible.

[0036] (Second Embodiment) Next, an example of the stator configuration of the second embodiment will be described with reference to Figures 4 and 5. The second embodiment is a modification of the first embodiment in which the magnetic wedge 7A is formed in an annular shape. In the following descriptions of each embodiment, elements common to the first embodiment will be denoted by the same reference numerals, and redundant explanations will be omitted as appropriate.

[0037] Figure 4 is a partially enlarged view of the stator in the rotating electric machine of the second embodiment. Figure 5(a) is a front view of the magnetic wedge applied in the second embodiment. Figure 5(b) is a plan view of the magnetic wedge in its mounted state. Figure 5(c) is a cross-sectional view taken along line AA of Figure 5(a). Figure 5(d) is a front view of the magnetic wedge in its mounted state.

[0038] As shown in Figures 5(a) and 5(d), the magnetic wedge 7A of the second embodiment is a thin plate-shaped member whose front view shape, when viewed from the inner circumference side of the stator 3, is formed in a vertically elongated annular shape. The magnetic wedge 7A of the second embodiment has a pair of first main body portions 11 and second main body portions 12 extending in the axial direction, and a pair of connecting portions 13, 13.

[0039] The first main body portion 11 of the magnetic wedge 7A contacts the first circumferential surface of the teeth portion 5b when attached to the stator 3. The second main body portion 12 of the magnetic wedge 7A contacts the second surface of the teeth portion 5b when attached to the stator 3. In the second embodiment as well, the teeth portion 5b that the first main body portion 11 contacts and the teeth portion 5b that the second main body portion 12 contacts are different teeth portions that are adjacent to each other. The thickness of the first main body portion 11 and the second main body portion 12 (vertical dimension in Figures 5(b) and (c)) is such that it can be fitted into the groove 5d of the teeth portion 5b.

[0040] In the second embodiment, the connecting portions 13, 13 are formed at the axial ends of the first main body portion 11 and the second main body portion 12, respectively, connecting the first main body portion 11 and the second main body portion 12 in the width direction. In other words, in the magnetic wedge 7A of the second embodiment, the first main body portion 11 and the second main body portion 12 are connected by two connecting portions 13, 13, and the overall shape is annular.

[0041] As shown in Figures 4 and 5(d), the axial lengths of the first main body 11 and the second main body 12 are formed to be longer than the axial length of the stator core 5, so that the respective connecting portions 13, 13 protrude axially from the stator core 5. As a result, in the second embodiment, the connecting portions 13, 13 are positioned to protrude axially from the slot 5c, and connect the first main body 11 and the second main body 12 in the width direction on the outside of the stator core 5.

[0042] Furthermore, a gap 14 is formed between the first main body portion 11 and the second main body portion 12 of the magnetic wedge 7A, extending axially between a pair of connecting portions 13, 13 and penetrating the magnetic wedge 7A in the thickness direction. Therefore, in the magnetic wedge 7A, the flow of magnetic flux between the first main body portion 11 and the second main body portion 12 is obstructed by the gap 14.

[0043] In the stator 3 of the second embodiment, as in the first embodiment, the stator 3 can be manufactured relatively easily by fitting a pre-formed annular coil 6 into the slot 5c from the radial direction, and the magnetic wedge 7A can suppress the radial detachment of the coil 6.

[0044] Furthermore, in the stator 3 of the second embodiment, similar to the first embodiment, salient poles in the circumferential direction are formed by the first main body portion 11 and the second main body portion 12 on the inner circumference side of the slot 5c, and an axially extending gap portion 14 is formed between the first main body portion 11 and the second main body portion 12 of the magnetic wedge 7A. As a result, the magnetic circuit of the stator 3 in the second embodiment approaches a semi-open slot shape, and the torque improvement effect of the stator 3 is improved compared to when a conventional closed slot shape magnetic wedge is applied.

[0045] Furthermore, in the stator 3 of the second embodiment, the connecting portions 13, 13 that connect the first main body 11 and the second main body 12 are not located within the slot. Therefore, in the second embodiment, the influence of the connecting portions 13 on the magnetic circuit is reduced compared to the first embodiment, and the torque improvement effect of the stator 3 is further enhanced.

[0046] (Third embodiment) Next, an example of the stator configuration of the third embodiment will be described with reference to Figures 6 and 7. The third embodiment is a modified version of the first embodiment in which the magnetic wedge 7B is formed in a C-shape.

[0047] Figure 6 is a partially enlarged view of the stator in the rotating electric machine of the third embodiment. Figure 7(a) is a front view of the magnetic wedge applied in the third embodiment. Figure 7(b) is a front view of the magnetic wedge in its mounted state.

[0048] As shown in Figures 7(a) and 7(b), the magnetic wedge 7B of the third embodiment is a thin plate-shaped member whose front view shape, when viewed from the inner circumference side of the stator 3, is formed in a C shape. The magnetic wedge 7B of the third embodiment has a pair of main body portions 11 and a second main body portion 12 extending in the axial direction, and a connecting portion 13.

[0049] The first main body portion 11 of the magnetic wedge 7B contacts the first circumferential surface of the teeth portion 5b when attached to the stator 3. The second main body portion 12 of the magnetic wedge 7B contacts the second surface of the teeth portion 5b when attached to the stator 3. Furthermore, the axial lengths of the first main body portion 11 and the second main body portion 12 are formed to be longer than the axial length of the stator core 5 so that the connecting portion 13 protrudes axially from the stator core. Similar to the first and second embodiments, the thickness of the first main body portion 11 and the second main body portion 12 is such that it can be fitted into the groove 5d of the teeth portion 5b.

[0050] In the third embodiment, the connecting portion 13 is formed at one axial end (upper side in the figure) of the first main body portion 11 and the second main body portion 12, and connects the first main body portion 11 and the second main body portion 12 in the width direction. In the third embodiment, the connecting portion 13 of the magnetic wedge 7B connects the first main body portion 11 and the second main body portion 12 by spanning the teeth portion 5b in the circumferential direction when attached to the stator 3.

[0051] In the third embodiment, as shown in Figures 6 and 7, the teeth portion 5b that the first main body portion 11 contacts and the teeth portion 5b that the second main body portion 12 contacts are the same teeth portion. That is, in the slot 5c formed between adjacent first teeth portion 5b and second teeth portion 5b, the first main body portion 11 of the first magnetic wedge 7B attached to the first teeth portion 5b and the second main body portion 12 of the second magnetic wedge 7B attached to the second teeth portion 5b are arranged facing each other.

[0052] Furthermore, an axially extending air gap 14 is formed between the first main body portion 11 of the first magnetic wedge 7B and the second main body portion 12 of the second magnetic wedge 7B. Therefore, within the slot 5c, the flow of magnetic flux between the first main body portion 11 of the first magnetic wedge 7B and the second main body portion 12 of the second magnetic wedge 7B is obstructed by the air gap 14.

[0053] In the stator 3 of the third embodiment, as in the first and second embodiments, the stator 3 can be manufactured relatively easily by fitting a pre-formed annular coil 6 into the slot 5c from the radial direction, and the magnetic wedge 7B can suppress the radial detachment of the coil 6.

[0054] Furthermore, in the stator 3 of the third embodiment, similar to the first and second embodiments, salient poles in the circumferential direction are formed by the first main body portion 11 and the second main body portion 12 on the inner circumference side of the slot 5c, and an axially extending gap portion 14 is formed between the first main body portion 11 and the second main body portion 12 in one slot 5c. As a result, the magnetic circuit of the stator 5 in the third embodiment approaches a semi-open slot shape, and the torque improvement effect of the stator 3 is improved compared to when a conventional closed slot shape magnetic wedge is applied.

[0055] Furthermore, in the third embodiment, the stator 3 has a connecting portion 13 positioned across the teeth portion 5b at the axial end of the stator core 5. Therefore, since the connecting portion 13 is not located within the slot in the stator 3 of the third embodiment, the influence of the connecting portion 13 on the magnetic circuit is reduced compared to the first embodiment, and the torque improvement effect of the stator 3 is further enhanced.

[0056] (A modified example of a magnetic wedge) Figure 8(a) shows a magnetic wedge 7C of the first modified example. The magnetic wedge 7C in Figure 8(a) has an overall C-shape, and the first main body 11 and the second main body 12 are connected by a connecting portion 13 provided at the axial end.

[0057] In the first modified example shown in Figure 8(a), the teeth 5b that contact the first body portion 11 and the teeth 5b that contact the second body portion 12 are different teeth portions that are positioned adjacent to each other. Also, the connecting portion 13 in Figure 8(a) is positioned to protrude axially from the slot 5c and connects the first body portion 11 and the second body portion 12 on the outside of the stator core 4. As a result, in the magnetic wedge 7C of Figure 8(a), salient poles in the circumferential direction are formed by the first body portion 11 and the second body portion 12 on the inner circumference side of the slot 5c, and an axially extending gap 14 is formed between the first body portion 11 and the second body portion 12 of the magnetic wedge 7C.

[0058] In the first modified example shown in Figure 8(a), the magnetic circuit of the stator 3 to which the magnetic wedge 7C is applied approaches a semi-open slot shape, thus improving the torque improvement effect of the stator 3 compared to the case where a conventional closed-slot magnetic wedge is applied.

[0059] Figure 8(b) is a perspective view showing a second modified magnetic wedge 7D. The magnetic wedge 7D in Figure 8(b) has a configuration in which a groove 15 extending in the axial direction is formed in the central part of the magnetic wedge 7D.

[0060] The magnetic wedge 7D in Figure 8(b), although not shown in the illustration, is fitted into teeth 5b at both ends in the width direction, each being different. In the magnetic wedge 7D of Figure 8(b), the parts on both sides in the width direction separated by the groove 15 correspond to the first main body 11 and the second main body 12, respectively, the bottom of the groove 15 corresponds to the connecting part 13, and the space of the groove 15 extending in the axial direction corresponds to the void 14.

[0061] In the second modified example shown in Figure 8(b), the magnetic wedges are connected in the width direction, but the flow of magnetic flux in the width direction is obstructed by the air gap in the groove portion 15 of the magnetic wedge. As a result, the magnetic circuit of the stator 3 to which the magnetic wedge 7D in Figure 8(b) is applied approaches a semi-open slot shape compared to the case of a magnetic wedge without groove portion 15, thus improving the torque improvement effect of the stator 3.

[0062] Also, although illustration is omitted, as another modification example, the extending direction of the gap portion 14 of each of the above magnetic wedges may be inclined with respect to the axial direction so that the gap portions 14 are arranged in a skewed shape.

[0063] (Example) In the example, for the motor with a semi-open slot stator (Comparative Example 1), the motor with an open slot stator to which a resin wedge is applied (Comparative Example 2), the motor with a closed slot stator to which a conventionally shaped magnetic wedge is applied (Comparative Example 3), and the motor with a stator to which the magnetic wedge of the first embodiment is applied (Example), the respective torques were calculated by simulation.

[0064] Here, FIG. 9(a) shows the magnetic circuit corresponding to the motor of Comparative Example 2 above together with a mathematical formula. FIG. 9(b) shows the magnetic circuit corresponding to the motor of Comparative Example 3 together with a mathematical formula. FIG. 9(c) shows the magnetic circuit corresponding to the motor of the example together with a mathematical formula. The magnetic circuits in FIGS. 9(a) to (c) are appropriately simplified within the range where there is no hindrance to the principle explanation.

[0065] Also, in FIGS. 9(a) to (c), NI indicates the magnetomotive force of the stator, and R st indicates the magnetic resistance of the stator, R gap indicates the magnetic resistance of the gap portion, R rt indicates the magnetic resistance of the rotor. Also, φ leak indicates the leakage magnetic flux between teeth, φ gap indicates the magnetic flux of the gap portion, φ st indicates the magnetic flux of the stator.

[0066] The torque of the motor is considered to be approximately proportional to the magnetic flux φ gap of the gap portion. As shown by the mathematical formulas in FIGS. 9(a) and (b), the magnetic flux of the gap portion (φ’ gap ) in Comparative Example 3 (closed slot) increases by the effect of the magnetic wedge due to the increase in the magnetic permeability near the gap and the reduction of the magnetic resistance of the gap portion (R’ gap ), but decreases by the amount multiplied by (1 + R st / R’ gap ) in the denominator.

[0067] On the other hand, as shown in the formulas in Figures 9(b) and (c), in the case of the embodiment, the denominator of the magnetic circuit is (1+R) as in Comparative Example 3. st / R' gap ) is absent, and the effect of the magnetic wedge is the magnetic resistance (R'') of the gap. gap This only reduces ). Therefore, according to the configuration of the embodiment, an increase in magnetic flux in the gap can be expected. The configuration of the embodiment is, for example, when the magnetomotive force NI of the stator is small and R st The effect is small when NI is very small. However, when NI is large and the permeability decreases due to magnetic saturation, R st In the case of high-load operation where the load becomes somewhat large, the effectiveness of the configuration in the embodiment is expected to increase.

[0068] Figure 10 also shows the calculated torque values ​​for each motor in Comparative Examples 1 to 3 and the Example at torque load rates of 20%, 40%, 60%, 80%, and 100%. In Figure 10, the calculated torque values ​​of the motors for each torque load rate are shown normalized by the calculated value for Comparative Example 1.

[0069] As shown in Figure 10, under each torque load condition, the torque of the motor in the embodiment is lower than the torque of the motor in Comparative Example 1 (semi-open slot), but is higher than the torque of the motors in Comparative Examples 2 and 3. Therefore, it can be seen that the configuration of the embodiment has a greater torque improvement effect compared to a conventional magnetic wedge like that in Comparative Example 3, and approaches the torque of the motor in Comparative Example 1 (semi-open slot).

[0070] The present invention is not limited to the embodiments described above, and various improvements and design modifications may be made without departing from the spirit of the invention.

[0071] For example, in the above embodiment, the case where the rotating electric machine 1 is a motor was described, but the rotating electric machine 1 may also be a generator.

[0072] For example, in the above embodiment, an example was described in which the armature to which the magnetic wedge is applied is the stator 3, but the armature to which the magnetic wedge is applied may be a wound rotor having coils.

[0073] Furthermore, although the above embodiment describes a configuration in which one magnetic wedge is fitted in the axial direction of the armature, a configuration in which multiple magnetic wedges are fitted in the axial direction of the armature is also possible.

[0074] Furthermore, the embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0075] 1...Rotating electric machine, 2...Rotor, 3...Stator, 4...Shaft, 5...Stator core, 5a...Yoke section, 5b...Teeth section, 5c...Slot, 5d...Groove, 6...Coil, 7,7A,7B,7C,7D...Magnetic wedge, 11...First main body section, 12...Second main body section, 13...Connecting section, 14...Gap section, 15...Groove

Claims

1. An armature core having a yoke portion, a plurality of teeth portions each projecting radially in one direction from the yoke portion, and slots formed between adjacent teeth portions, A coil housed in the aforementioned slot for exciting the armature core, The invention comprises a magnetic wedge containing a magnetic material and positioned in the slot on one radial side of the coil and facing the coil, The aforementioned magnetic wedge is, The armature core has a first main body portion that extends in the axial direction and contacts the first surface of the teeth portion, The armature core has a second main body portion that extends in the axial direction and contacts the second surface of the teeth portion that is opposite to the first surface, It has a connecting portion that connects the first main body and the second main body in the circumferential direction, Within the slot, a gap is formed between the first main body and the second main body, extending in the axial direction of the armature core. The connecting portion is positioned so as to protrude from the slot on one side in the axial direction, rather than being located within the slot, and connects the first main body and the second main body, which are located within one slot, at a position where they overlap with the slot in the circumferential direction. Armature.

2. A rotating electric machine comprising the armature described in claim 1.

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