Rotor and rotary electric machine

Abstract

To secure reduction effect on noise caused by torque ripple, while reducing leakage of a magnetic flux.SOLUTION: A rotor 100 according to an embodiment includes a rotor shaft, a plurality of permanent magnets, and a rotor core 120. Formed in the rotor core 120 are a wide-angle flux barrier band 130 having wide-angle FBB openings 132, 133 or a narrow-angle flux barrier band 140 having narrow-angle FBB openings 142, 143, which has a plurality of electromagnetic steel plates and is formed in a substantially projecting shape with respect to a rotation center axis in the magnetic pole. Each of a circumferential angle Θ1a and a circumferential angle Θ1b formed by two wall surfaces of the wide-angle FBB openings and a d-axis is larger than each of a circumferential angle Θ2b and a circumferential angle Θ2b formed by two wall surfaces of the narrow-angle FBB openings and the d-axis, and Θ1b is larger than Θ1a.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a rotor and a rotating electric machine. [Background technology]

[0002] In a rotating electric machine with an embedded magnet rotor, a through-hole extending in the axial direction is formed in a region near the radial outside of the rotor core to house a permanent magnet. Typically, this through-hole has not only a space for housing the permanent magnet, but also partial spaces on the radial outside and inside. These partial spaces act as flux barriers that prevent magnetic flux from passing through.

[0003] In many cases, a top bridge, which is part of the rotor core, exists between this radially outer partial space and the outer surface of the rotor core, and is part of the element that ensures the structural strength of the rotor core.

[0004] This top bridge has a narrowed width as part of the flux barrier band, but the magnetic flux passing through the top bridge remains only within the rotor and becomes leakage flux that does not interlink with the stator, resulting in a decrease in the torque efficiency of the rotating electric machine.

[0005] Due to this background, there are many examples of rotors that use a system in which the top bridge is removed and an opening is provided that connects the above-mentioned radially outer flux barrier to the outer space of the rotor core (the gap space between the rotor and stator). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-230070 Summary of the Invention [Problem to be solved by the invention]

[0007] In an interior permanent magnet rotor without a top bridge, while the presence of openings as described above can reduce leakage flux, there is a problem of torque ripple. Specifically, as viewed from the stator winding side, openings are formed circumferentially on the rotor side, causing periodic changes in magnetic resistance in the circumferential direction. This causes torque ripple, which increases or decreases the value of the rotational torque, and is a cause of mechanical vibration and noise during rotation.

[0008] The problem to be solved by the present invention is to provide a rotor and a rotating electric machine that can ensure the effect of reducing noise caused by torque ripple while reducing leakage magnetic flux. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, a rotor according to an embodiment of the present invention includes a rotor shaft extending in the axial direction of a central axis of rotation, a plurality of permanent magnets extending in the axial direction and arranged equally in the circumferential direction and symmetrically with respect to a d-axis extending from the central axis of rotation when viewed in a cross section perpendicular to the central axis of rotation, and a plurality of electromagnetic steel plates attached to the radial outside of the rotor shaft and laminated so that the d-axis overlaps in the axial direction, and the rotor accommodates the plurality of permanent magnets and has non-magnetic regions and bridges in magnetic poles which are divided circumferential angle regions. and a rotor core on which either a wide-angle flux barrier band or a narrow-angle flux barrier band is formed, the wide-angle flux barrier band having a wide-angle FBB opening communicating with an outer circumferential surface of the rotor core, the narrow-angle flux barrier band having a narrow-angle FBB opening communicating with the outer circumferential surface of the rotor core, and a circumferential angle Θ is defined as a circumferential angle formed by a wall surface forming the wide-angle FBB opening on a side closer to the d-axis and a tangent extending from the rotation central axis. 1a The inclined angle Θ is defined as the inclined angle formed by the wall surface farther from the d-axis that forms the wide-angle FBB opening and the tangent line extending from the rotation center axis. 1b The inclined angle Θ is defined as the inclined angle formed by the wall surface near the d-axis that forms the narrow-angle FBB opening and the tangent line extending from the rotation center axis. 2aThe inclined angle Θ is defined as the inclined angle formed by the wall surface farther from the d-axis that forms the narrow-angle FBB opening and the tangent line extending from the rotation center axis. 2b When the angle of circumference Θ 1a is the inscribed angle Θ 2a The larger the inscribed angle Θ 1b is the inscribed angle Θ 2b and the inclination angle Θ 1b is the inscribed angle Θ 1a The larger the inscribed angle Θ 2b is the inscribed angle Θ 2a It is characterized by being larger. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a vertical cross-sectional view showing the configuration of a rotating electric machine according to an embodiment; [Figure 2] 1 is a cross-sectional view showing a configuration of a part of a rotating electric machine according to an embodiment; [Figure 3] FIG. 2 is a cross-sectional view showing a rotor according to the embodiment. [Figure 4] FIG. 2 is a partial front view of an electromagnetic steel sheet showing a wide-angle flux barrier band for one pole of a rotor core that constitutes a rotor according to an embodiment. [Figure 5] FIG. 10 is a partial front view of an electromagnetic steel sheet showing details of an opening that is part of a wide-angle flux barrier band of a rotor core that constitutes a rotor according to an embodiment. [Figure 6] FIG. 2 is a partial front view of an electromagnetic steel sheet showing a narrow-angle flux barrier band for one pole of a rotor core that constitutes a rotor according to an embodiment. [Figure 7] FIG. 10 is a partial front view of an electromagnetic steel sheet showing details of an opening that is part of a narrow-angle flux barrier band of a rotor core that constitutes a rotor according to an embodiment. [Figure 8] FIG. 2 is a development view showing a lamination state of electromagnetic steel sheets in a rotor core of the rotor according to the embodiment. [Figure 9] FIG. 2 is a development view showing a method for laminating electromagnetic steel sheets in a rotor core of a rotor according to an embodiment. [Figure 10]FIG. 10 is a development view showing a modified example of a lamination method of electromagnetic steel sheets in a rotor core of the rotor according to the embodiment. [Figure 11] FIG. 4 is a development view showing a lamination method of a first modified example of electromagnetic steel sheets in a rotor core of a rotor according to an embodiment. [Figure 12] FIG. 10 is a development view showing a lamination method of a second modified example of the electromagnetic steel sheets in the rotor core of the rotor according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, a rotor and a rotating electric machine according to an embodiment of the present invention will be described with reference to the drawings. Here, the same or similar parts are denoted by the same reference numerals, and duplicated explanations will be omitted.

[0012] Fig. 1 is a vertical cross-sectional view showing the configuration of a rotating electric machine 1 according to an embodiment, and Fig. 2 is a horizontal cross-sectional view showing the configuration of a part of the rotating electric machine 1 according to an embodiment.

[0013] The rotating electric machine 1 includes a rotor 100, a stator 10, a bearing 21, a bearing bracket 22, and a frame 23.

[0014] The rotor 100 has a rotor shaft 110 extending in a direction (axial direction) parallel to the central axis of rotation CL, a rotor core 120 attached to the radially outer side of the rotor shaft 110, and a plurality of permanent magnets 160 housed inside the rotor core 120. The rotor core 120 is formed by laminating electromagnetic steel sheets 121. Note that while FIG. 1 shows an example in which the rotor core 120 has a plurality of electromagnetic steel sheets 121, the present invention is not limited to this and can also be applied to a solid rotor in which the rotor shaft and rotor core are integrated.

[0015] The stator 10 has a stator core 11 disposed radially outside the rotor core 120 so as to surround the rotor core 120 with a gap therebetween, and a stator winding 15 (FIG. 1) wound around the stator core 11. As shown in FIG. 2, a number of stator slots 11s are formed at intervals in the circumferential direction on the inner periphery of the stator core 11. Furthermore, adjacent stator slots 11s form respective stator teeth 11t.

[0016] The bearings 21 are arranged on both outsides of the rotor core 120 in the axial direction of the rotor shaft 110, and rotatably support the rotor shaft 110. The bearing brackets 22 statically support the respective bearings 21. The frame 23 is cylindrical, and both ends thereof are connected to the respective bearing brackets 22, and support the respective bearing brackets 22.

[0017] The rotor 100 includes a rotor shaft 110 extending in the direction of the rotation axis, a rotor core 120 attached to the rotor shaft 110 , and a plurality of permanent magnets 160 .

[0018] The electromagnetic steel sheets 121 (FIG. 1) of the rotor core 120 are formed with punched portions through which the rotor shaft 110 passes and punched portions through which the permanent magnets 160 pass. By stacking a plurality of electromagnetic steel sheets 121, through holes extending in the axial direction are formed in the rotor core 120.

[0019] 2 illustrates an example in which the rotor 100 has eight magnetic poles 101. As shown in Fig. 2, the rotor core 120 is formed with flux barrier bands 120f corresponding to each magnetic pole 101 of the rotor 100. Each flux barrier band 120f forms an outer core portion 120a on the radially outer side, which is separated from an inner core portion 120b on the radially inner side.

[0020] 3 is a cross-sectional view showing the rotor 100 according to the embodiment. In addition, with regard to the rotor core 120, FIG. 3 is also a front view of the electromagnetic steel sheets 121.

[0021] As shown in FIG. 3 , imaginary d-axes, which are the centers of the magnetic poles 101, extend radially from the central axis CL at equal angular intervals in the circumferential direction. Two flat plate-shaped permanent magnets 160 are arranged symmetrically about the d-axis. The two permanent magnets 160 are arranged such that the side closer to the d-axis is radially inward. Here, the two permanent magnets 160 have the same cross section, but this is not limiting. In other words, as long as the magnet storage section formed in the rotor core 120 is configured to be able to store the two permanent magnets 160 in the axial direction, the two permanent magnets 160 do not necessarily have the same cross section.

[0022] 3 also shows electromagnetic steel sheets 121. The following description of rotor core 120 also includes a description of electromagnetic steel sheets 121.

[0023] As described above, the rotor core 120 has a flux barrier band 120f formed on each magnetic pole 101. The flux barrier band 120f is a magnetically reluctant portion that connects two points on the rotor core outer circumferential surface 120s. The flux barrier band 120f is a collective term for the wide-angle flux barrier band 130 and the narrow-angle flux barrier band 140. Two wide-angle flux barrier bands 130 and two narrow-angle flux barrier bands 140 are alternately formed in the circumferential direction.

[0024] Here, n wide-angle flux barrier bands 130 and n narrow-angle flux barrier bands 140 are alternately arranged (n is a natural number greater than or equal to 1 and less than half the number of magnetic poles). In Figure 2, the number of magnetic poles is 8, and half the number of magnetic poles is 4, so n is a natural number greater than or equal to 1 and less than or equal to 4, but the case where n is 2 is shown.

[0025] As shown in FIG. 3, the openings at both ends of the wide-angle flux barrier band 130 are spaced apart by a circular angle Θ clockwise from the d axis. 11a , the inscribed angle Θ counterclockwise from the d axis 12aThe openings at both ends of the narrow-angle flux barrier band 140 are formed at a position at a circumferential angle Θ clockwise from the d axis. 21a , Θ counterclockwise from the d axis 22a In the wide-angle flux barrier band 130, the opening is formed at a position symmetrical with respect to the d axis, that is, at a circumferential angle Θ 11a and inscribed angle Θ 12a The inscribed angle Θ is equal 1a In the narrow-angle flux barrier band 140, the opening may be symmetrical about the d axis, i.e., the circumferential angle Θ 21a and inscribed angle Θ 22a The inscribed angle Θ is equal 2a may be.

[0026] FIG. 4 is a partial front view of an electromagnetic steel sheet 121 showing wide-angle flux barrier bands 130 for one pole of a rotor core 120 that constitutes a rotor 100 according to the embodiment.

[0027] The wide-angle flux barrier band 130 is formed in a radially inward convex shape so as to connect two points on the rotor core outer peripheral surface 120s. In detail, the wide-angle flux barrier band 130 has a wide-angle FBB first opening 132, a permanent magnet storage hole 131, a center bridge 135a, a central flux barrier 135, a center bridge 135b, the permanent magnet storage hole 131, and a wide-angle FBB second opening 133.

[0028] The two permanent magnet storage holes 131 are formed to store permanent magnets 160 (FIG. 2), respectively. In the wide-angle flux barrier band 130, the portions other than the wide-angle FBB first opening 132 and the wide-angle FBB second opening 133 are formed symmetrically with respect to the d-axis.

[0029] The wide-angle FBB first opening 132 is formed by a wide-angle FBB first opening first wall 132a on the side closer to the d-axis and a wide-angle FBB first opening second wall 132b on the side farther from the d-axis. The wide-angle FBB second opening 133 is formed by a wide-angle FBB second opening first wall 133a on the side closer to the d-axis and a wide-angle FBB second opening second wall 133b on the side farther from the d-axis. If there is no opening, a top bridge is usually formed along the rotor core outer peripheral surface 120s, and the opening corresponds to the removed portion if this top bridge is removed.

[0030] Here, in a cross section perpendicular to the central axis CL (FIG. 1), a tangent line L extending radially from the central axis CL and tangent to the first wall 132a of the wide-angle FBB first opening is 11a The inscribed angle between the d axis and the 11a A tangent line L extending radially from the central axis CL and tangent to the wide-angle FBB first opening second wall 132b is defined as 11b The inscribed angle between the d axis and the 11b Also, the inscribed angle Θ 11a and inscribed angle Θ 11b The difference between the circumferential angle θ and the circumferential angle θ , i.e., the circumferential angle corresponding to the circumferential width of the opening 132, is defined as the opening angle θ 11w Let's say.

[0031] A tangent line L extending radially from the central axis CL and tangent to the first wall 133a of the wide-angle FBB second opening 12a The inscribed angle between the d axis and the 12a A tangent line L extending radially from the central axis CL and tangent to the second wall 133b of the wide-angle FBB second opening portion is defined as 12b The inscribed angle between the d axis and the 12b Also, the inscribed angle Θ 12a and inscribed angle Θ 12b The difference between the two angles, i.e., the circumferential angle corresponding to the circumferential width of the opening 133, is defined as the opening angle Θ 12w Let's say.

[0032] In addition, the Θ shown in Figure 4 11a and Θ 12a In FIG. 3, for the sake of simplicity, both are denoted as Θ1. 11a and Θ 12aThe angles may be different or may be the same.

[0033] How to draw tangent lines will be explained with reference to Figure 5.

[0034] Rotor core 120 is divided into outer core portion 120a and inner core portion 120b by wide-angle flux barrier band 130. Outer core portion 120a is connected to inner core portion 120b by two center bridges 135a and 135b. The two center bridges 135a and 135b resist the centrifugal force acting on outer core portion 120a when rotor 100 rotates.

[0035] FIG. 5 is a partial front view of an electromagnetic steel sheet 121 showing details of an opening 132 that is part of a wide-angle flux barrier band 130 of a rotor core 120 that constitutes a rotor 100 according to the embodiment.

[0036] If there is no opening, the outer edge of the top bridge in the radial direction is drawn as a curve L 01a , the inner radial edge is curved L 01b Let the curve L 01a is a part of the rotor core outer circumferential surface 120s.

[0037] The wide-angle FBB first opening first wall 132a and the wide-angle FBB first opening second wall 132b that form the wide-angle FBB first opening 132 are arranged in the radial direction along curves L 01b From the intersection with the curve L 01a The range is up to the intersection point (rotor core outer surface 120s) with

[0038] Among the intersections of the lines extending from the first wall 132a of the wide-angle FBB first opening and the rotation center axis CL, the intersection that forms the largest inclination angle with the d axis is the intersection P 11 In this case, the intersection point P 11 However, the wide-angle FBB first opening first wall 132a and the tangent line L 11a Contact point P 11 This becomes:

[0039] Similarly, among the intersections of the wide-angle FBB first opening second wall 132b and the line extending from the rotation center axis CL, the intersection that forms the largest inclined angle with the d axis is the intersection P 12 In this case, the intersection point P 12 However, the wide-angle FBB first opening second wall 132b and the tangent line L 11b Contact point P 12 This becomes:

[0040] In other words, among the lines extending from the rotation center axis CL, the line that has an intersection including a tangent point with the wide-angle FBB first opening first wall 132a and forms the largest circumferential angle with the d-axis is the tangent line L of the wide-angle FBB first opening first wall 132a. 11a Similarly, among the lines extending from the rotation center axis CL, the line that has an intersection including a tangent point with the wide-angle FBB first opening second wall 132b and forms the largest circumferential angle with the d-axis is the tangent line L of the wide-angle FBB first opening second wall 132b. 11b is.

[0041] Here, the opening angle Θ 11w The opening dimension w corresponding to 11 First, define the tangent line L 11a The intersection point between the rotor core outer surface 120s and P S11 Also, the tangent line L 11b The intersection point between the rotor core outer surface 120s and P S12 Intersection point P S11 and intersection point P S12 The distance between the opening and 11 If the thickness of the electromagnetic steel sheet 121 is t, the opening dimension w 11 is greater than 2t. Similarly, the opening angle Θ 12w The opening dimension w corresponding to 12 The same applies to the opening dimension w 12 is greater than 2 tons.

[0042] FIG. 6 is a partial front view of an electromagnetic steel sheet 121 showing narrow-angle flux barrier bands 140 for one pole of a rotor core 120 that constitutes a rotor 100 according to the embodiment.

[0043] The narrow-angle flux barrier band 140 is formed in a radially inward convex shape so as to connect two points on the rotor core outer peripheral surface 120s. In detail, the narrow-angle flux barrier band 140 has a narrow-angle FBB first opening 142, a permanent magnet storage hole 131, a center bridge 135a, a central flux barrier 135, a center bridge 135b, a permanent magnet storage hole 131, and a narrow-angle FBB second opening 143.

[0044] The permanent magnet storage holes 131, center bridge 135a, central flux barrier 135, center bridge 135b, and permanent magnet storage holes 131 of the wide-angle flux barrier band 130 and the narrow-angle flux barrier band 140 are formed to have the same shapes and dimensions.

[0045] That is, the wide-angle flux barrier band 130 and the narrow-angle flux barrier band 140 are formed so that, except for the wide-angle FBB first opening 132 and the wide-angle FBB second opening 133 of the wide-angle flux barrier band 130, and the narrow-angle FBB first opening 142 and the narrow-angle FBB second opening 143 of the narrow-angle flux barrier band 140, the other parts overlap with each other, i.e., can be seen through in the axial direction.

[0046] The narrow-angle FBB first opening 142 is formed by a narrow-angle FBB first opening first wall 142a on the side closer to the d-axis and a narrow-angle FBB first opening second wall 142b on the side farther from the d-axis. The narrow-angle FBB second opening 143 is formed by a narrow-angle FBB second opening first wall 143a on the side closer to the d-axis and a narrow-angle FBB second opening second wall 143b on the side farther from the d-axis. If there is no opening, a top bridge is usually formed along the rotor core outer peripheral surface 120s, and the opening corresponds to the removed portion if this top bridge is removed.

[0047] Here, in a cross section perpendicular to the central axis CL (FIG. 1), a tangent line L extending radially from the central axis CL and tangent to the first wall 142a of the narrow angle FBB first opening is 21a The inscribed angle between the d axis and the 21aA tangent line L extending radially from the central axis CL and tangent to the narrow angle FBB first opening second wall 142b is defined as 21b The inscribed angle between the d axis and the 21b Also, the inscribed angle Θ 21a and inscribed angle Θ 21b The difference between the circumferential angle and the circumferential angle of the opening 142 is defined as the opening angle Θ 21w Let's say.

[0048] A tangent line L extending radially from the central axis CL and tangent to the first wall 143a of the narrow angle FBB second opening 22a The inscribed angle between the d axis and the 22a A tangent line L extending radially from the central axis CL and tangent to the second wall 143b of the narrow angle FBB second opening portion is defined as 22b The inscribed angle between the d axis and the 22b Also, the inscribed angle Θ 22a and inscribed angle Θ 22b The difference between the circumferential angle and the circumferential angle of the opening 143 is defined as the opening angle Θ 22w Let's say.

[0049] In addition, the Θ shown in Figure 6 21a and Θ 22a In FIG. 3, for the sake of simplicity, both are denoted as Θ2. 21a and Θ 22a The angles may be different or may be the same.

[0050] FIG. 7 is a partial front view of an electromagnetic steel sheet 121 showing details of an opening 142 that is part of a narrow-angle flux barrier band 140 of a rotor core 120 that constitutes a rotor 100 according to the embodiment.

[0051] If there is no opening, the outer radial part of the top bridge that exists is curved L 02a , the inner radial part is curved L 02b Let the curve L 02a is a part of the rotor core outer circumferential surface 120s.

[0052] The narrow angle FBB first opening first wall 142a and the narrow angle FBB first opening second wall 142b that form the narrow angle FBB first opening 142 are arranged in the radial direction along a curve L 02b From the intersection with the curve L 02a The range is up to the intersection point (rotor core outer surface 120s) with

[0053] Among the intersections of the first wall 142a of the narrow angle FBB first opening and the line extending from the rotation center axis CL, the intersection that forms the largest inclination angle with the d axis is the intersection P 21 In this case, the intersection point P 21 However, the narrow angle FBB first opening first wall 142a and the tangent line L 21a Contact point P 21 This becomes:

[0054] Similarly, among the intersections of the narrow-angle FBB first opening second wall 142b and the line extending from the rotation center axis CL, the intersection that forms the largest inclined angle with the d axis is the intersection P 22 In this case, the intersection point P 22 The narrow angle FBB first opening second wall 142b and the tangent line L 21b Contact point P 22 This becomes:

[0055] In other words, among the lines extending from the rotation center axis CL, the line that has an intersection point including a tangent point with the first wall 142a of the narrow angle FBB first opening and that forms the largest circumferential angle with the d axis is the tangent line L of the first wall 142a of the narrow angle FBB first opening. 21a Similarly, among the lines extending from the rotation center axis CL, the line that has an intersection including a tangent point with the narrow angle FBB first opening second wall 142b and forms the largest circumferential angle with the d axis is the tangent line L of the narrow angle FBB first opening second wall 142b. 21b is.

[0056] Here, the opening angle Θ 21w The opening dimension w corresponding to 21 First, define the tangent line L 21a The intersection point between the rotor core outer surface 120s and P S21 Also, the tangent line L 21b The intersection point between the rotor core outer surface 120s and P S22 Intersection point P S21and intersection point P S22 The distance between the opening and 21 If the thickness of the electromagnetic steel sheet 121 is t, the opening dimension w 21 is greater than 2t. Similarly, the opening angle Θ 22w The opening dimension w corresponding to 22 The same applies to the opening dimension w 22 is greater than 2 tons.

[0057] Fig. 8 is a development view showing the lamination state of electromagnetic steel sheets 121 in rotor core 120 of rotor 100 according to the embodiment. Fig. 8 is a development view in the circumferential direction of rotor core 120 as viewed from the radial outside in the direction of central axis CL.

[0058] Fig. 8 shows a state in which identical magnetic steel sheets 121 are stacked, with every other sheet shifted by two poles in the circumferential direction. Therefore, Fig. 8 shows a state in which wide-angle flux barrier bands 130 centered on the d-axis and narrow-angle flux barrier bands 140 centered on the d-axis are alternately present. The white areas represent the openings.

[0059] The respective inclined angles have been explained with reference to Figures 4 to 7, and therefore will not be explained here. The relationship between the wide-angle flux barrier band 130 and the narrow-angle flux barrier band 140 will be explained below.

[0060] First, the inclination angles of the openings 132 and 133 of the wide-angle flux barrier band 130 at the wall surfaces closer to the d-axis are larger than the inclination angles of the openings 142 and 143 of the narrow-angle flux barrier band 140 at the wall surfaces closer to the d-axis. 11a >Circular angle Θ 21a , inscribed angle Θ 12a >Circular angle Θ 22a The following relationship is established.

[0061] Furthermore, the inclination angles of the openings 132 and 133 of the wide-angle flux barrier band 130 at the wall surfaces farther from the d-axis are larger than the inclination angles of the openings 142 and 143 of the narrow-angle flux barrier band 140 at the wall surfaces farther from the d-axis.11b >Circular angle Θ 21b , inscribed angle Θ 12b >Circular angle Θ 22b The following relationship is established.

[0062] Furthermore, the inclined angles of the openings 142 and 143 of the narrow-angle flux barrier band 140 at the wall surfaces farther from the d-axis are larger than the inclined angles of the openings 132 and 133 of the wide-angle flux barrier band 130 at the wall surfaces closer to the d-axis. That is, the inclined angle Θ 21b >Circular angle Θ 11a , inscribed angle Θ 22b >Circular angle Θ 12a That is, the inscribed angle Θ 21b from the inscribed angle Θ 11a The first common aperture angle ΔΘ1, which is the difference obtained by subtracting ΔΘ from the first common aperture angle ΔΘ, becomes positive. As a result, the first common aperture 152 is formed, which has a first common aperture width d1 corresponding to the first common aperture angle ΔΘ. 22b from the inscribed angle Θ 12a The second common aperture angle ΔΘ2, which is the difference obtained by subtracting ΔΘ2, becomes positive. As a result, the second common aperture 153 is formed having the second common aperture width d2 corresponding to the second common aperture angle ΔΘ2.

[0063] In this way, a first common aperture 152 and a second common aperture 153 are formed as the common aperture 150. That is, when the wide-angle flux barrier band 130 and the narrow-angle flux barrier band 140 are overlapped with their d-axes aligned, there is a common aperture 150 that is an opening in both the wide-angle flux barrier band 130 and the narrow-angle flux barrier band 140. Here, the first common aperture width d1 and the second common aperture width d2, which are the common aperture width d, are positive and smaller than 2t.

[0064] From the above, the following equations (1) and (2) hold true (where i, j = 1, 2). w ij >2t ···(1) 2t>d ij >0 (2)

[0065] When the wide-angle flux barrier band 130 and the narrow-angle flux barrier band 140 are each symmetrical with respect to the d-axis, the following holds.

[0066] For the wide-angle flux barrier band 130, the inscribed angle Θ 11a and inscribed angle Θ 12a are equal inscribed angles Θ 1a , inscribed angle Θ 11b and inscribed angle Θ 12b are equal inscribed angles Θ 1b The openings 132 and 133 of the wide-angle flux barrier band 130 are spaced apart by a circular angle Θ 1b and inscribed angle Θ 1a The opening angle Θ is the difference between 1w and opening angle Θ 1w The opening dimension w1 corresponds to

[0067] For the narrow-angle flux barrier band 140, the inscribed angle Θ 21a and inscribed angle Θ 22a are equal inscribed angles Θ 2a , inscribed angle Θ 21b and inscribed angle Θ 22b are equal inscribed angles Θ 2b The openings 142 and 143 of the narrow-angle flux barrier band 140 are formed at a circumferential angle Θ 2b and inscribed angle Θ 2a The opening angle Θ is the difference between 2w and opening angle Θ 2w The opening dimension w2 corresponds to

[0068] As a result, when the wide-angle flux barrier band 130 and the narrow-angle flux barrier band 140 are each symmetrical with respect to the d-axis, the first common aperture width d1 and the second common aperture width d2 are the same common aperture width d.

[0069] <Operation of this embodiment> The operation of the rotor core 120 according to this embodiment configured as described above will be described with reference to FIG.

[0070] When rotor core 120 is viewed from the radial outside, that is, from the stator winding side, toward rotation center CL, the state of the openings changes along the circumferential direction shown in FIG.

[0071] Specifically, at the angular position on the leftmost side of the drawing, there is no opening in the stacking direction.

[0072] Next, Θ in the circumferential direction from the d axis 12b From an angle position that is smaller by Θ, rotate counterclockwise from the d axis. 22b Only the opening of the wide-angle flux barrier band 130 (wide-angle FBB second opening 133) exists between the wide-angle flux barrier band 130 and the angular position shifted by 1 / 2.

[0073] Next, Θ is rotated counterclockwise from the d axis. 22b From the angular position shifted by Θ in the counterclockwise direction from the d axis 12a Between this and the angular position shifted by 100°, there are both the opening of the wide-angle flux barrier band 130 (wide-angle FBB second opening 133) and the opening of the narrow-angle flux barrier band 140 (narrow-angle FBB second opening 143). That is, this is the region where the second common opening 153 exists.

[0074] Next, Θ is rotated counterclockwise from the d axis. 12a From the angle position shifted by Θ in the counterclockwise direction from the d axis 22a Only the opening of the narrow-angle flux barrier band 140 (narrow-angle FBB second opening 143) exists between the narrow-angle flux barrier band 140 and the angular position shifted by the angle θ.

[0075] Next, Θ is rotated counterclockwise from the d axis. 22a From the angular position shifted by Θ in the clockwise direction from the d axis 21a In the region including the d axis up to the angular position shifted by , there are no openings in the stacking direction.

[0076] Next, Θ in the clockwise direction from the d axis 21a From the angular position shifted by Θ in the clockwise direction from the d axis 11aOnly the opening of the narrow-angle flux barrier band 140 (narrow-angle FBB first opening 142) exists between the narrow-angle flux barrier band 140 and the angular position shifted by 1 / 2.

[0077] Next, Θ in the clockwise direction from the d axis 11a From the angular position shifted by Θ in the clockwise direction from the d axis 21b Between this and the angular position shifted by 100°, there are both the opening of the wide-angle flux barrier band 130 (wide-angle FBB first opening 132) and the opening of the narrow-angle flux barrier band 140 (narrow-angle FBB first opening 142). That is, this is the region where the first common opening 152 exists.

[0078] Next, Θ in the clockwise direction from the d axis 21b From the angular position shifted by Θ in the clockwise direction from the d axis 11b Only the opening of the wide-angle flux barrier band 130 (wide-angle FBB first opening 132) exists between the wide-angle flux barrier band 130 and the angular position shifted by 1 / 2.

[0079] Next, Θ in the clockwise direction from the d axis 11b From the angular position shifted by this amount, there is no opening in the lamination direction up to the next pole.

[0080] In this way, the above state is repeated in the circumferential direction.

[0081] <Lamination method> Here, a method for laminating the electromagnetic steel sheets 121 will be described.

[0082] FIG. 9 is a development view showing a method for laminating electromagnetic steel sheets 121 in a rotor core 120 of a rotor 100 according to the embodiment.

[0083] Here, each magnetic steel sheet 121 has eight magnetic poles 101 (FIG. 2). In FIG. 9, A indicates a magnetic pole 101 having a wide-angle flux barrier band 130, and B indicates a magnetic pole 101 having a narrow-angle flux barrier band 140.

[0084] For ease of explanation, Fig. 9 shows the first four sheets of the laminate 125 of electromagnetic steel sheets 121 spaced apart. The second electromagnetic steel sheet 121 is the first electromagnetic steel sheet 121 shifted circumferentially by two magnetic poles 101. As a result, A and B are reversed in the second sheet compared to the first sheet. A and B are reversed in the third, fourth and subsequent sheets in the same manner.

[0085] As explained with reference to Fig. 2, each of the electromagnetic steel sheets 121 has n magnetic poles 101 with wide-angle flux barrier bands 130 and n magnetic poles 101 with narrow-angle flux barrier bands 140 alternately arranged in the circumferential direction (n is a natural number greater than or equal to 1 / 2 the number of magnetic poles). Two adjacent electromagnetic steel sheets 121 among the plurality of electromagnetic steel sheets 121 are offset from each other in the circumferential direction by n poles, i.e., by n magnetic poles 101. Fig. 9 shows the case where n is 2.

[0086] For ease of explanation, Fig. 9 shows the first four sheets of the laminate 125 of electromagnetic steel sheets 121 spaced apart. The second electromagnetic steel sheet 121 is the first electromagnetic steel sheet 121 shifted circumferentially by two magnetic poles 101. As a result, A and B are reversed in the second sheet compared to the first sheet. A and B are reversed in the third, fourth and subsequent sheets in the same manner.

[0087] FIG. 10 is a development view showing a modified example of the lamination method of the electromagnetic steel sheets 121 in the rotor core 120 of the rotor 100 according to the embodiment.

[0088] The laminate 125r is formed by laminating electromagnetic steel sheets 121 in the same direction. The laminate 125s is also formed by laminating electromagnetic steel sheets 121 in the same direction. The electromagnetic steel sheets 121 of the laminate 125r and the laminate 125s are shifted in the circumferential direction by two magnetic poles 101, with A and B reversed. The rotor core 120 is formed by laminating the laminate 125r and the laminate 125s.

[0089] Although FIG. 10 shows a case where there is one each of the laminated body 125r and the laminated body 125s, the rotor core 120 may be configured by repeatedly laminating them.

[0090] FIG. 11 is a development view showing a lamination method of a first modified example of the electromagnetic steel sheets in the rotor core 120 of the rotor 100 according to the embodiment.

[0091] In the electromagnetic steel sheet 122 of the first modification, A and B are arranged alternately in the circumferential direction. In this case, odd-numbered ones have the same arrangement, and even-numbered ones have the same arrangement, but are shifted by one pole in the circumferential direction.

[0092] In FIG. 11, the electromagnetic steel plates 122 are offset from one another in the circumferential direction, but each may be formed by stacking a plurality of sheets, similar to the example shown in FIG.

[0093] FIG. 12 is a development view showing a second modified example of a lamination method for the electromagnetic steel sheets in the rotor core 120 of the rotor 100 according to the embodiment.

[0094] In the second modified example, all of the electromagnetic steel sheets 123a are arranged with A, and all of the electromagnetic steel sheets 123b are arranged with B. The electromagnetic steel sheets 123a and the electromagnetic steel sheets 123b are alternately stacked to form the laminate 127. Note that, as in the example shown in FIG. 10, a plurality of each may be stacked.

[0095] Any of the above lamination methods may be used.

[0096] <Effects of this embodiment> When the positions of the openings are the same for all the electromagnetic steel sheets, the state changes from no openings in the stacking direction to a state where all the electromagnetic steel sheets have openings in the stacking direction, and then to a state where there are no openings in the stacking direction again, and this cycle is repeated. As a result, when viewed from the stator winding 15 side, the magnetic resistance of rotor core 120 alternates between two states: large and small.

[0097] On the other hand, in the rotor core 120 according to this embodiment, there is a state in which there is no opening on either side. In other words, when viewed from the stator winding 15 side, the rotor core 120 has not only a state where the magnetic resistance is large and a state where the magnetic resistance is small, but also a state intermediate between these two. As a result, the change in the magnetic resistance of the rotor core 120 viewed from the stator winding 15 side becomes smoother.

[0098] In this way, with a configuration that does not have a top bridge and reduces leakage magnetic flux, it is possible to ensure the effect of reducing noise caused by torque ripple.

[0099] According to the embodiments described above, it is possible to provide a rotor and a rotating electric machine that can ensure the effect of reducing noise caused by torque ripple while reducing leakage magnetic flux.

[0100] [Other embodiments] Although the embodiments of the present invention have been described above, they are presented as examples and are not intended to limit the scope of the invention. Furthermore, features of each embodiment may be combined. Furthermore, the embodiments may be implemented in various other forms, and various omissions, substitutions, and modifications may be made without departing from the spirit of the invention. The embodiments and their modifications are intended to be included within the scope and spirit of the invention, as well as within the scope of the invention and its equivalents as set forth in the claims. [Explanation of symbols]

[0101] 1...rotating electric machine, 10...stator, 11...stator core, 11s...stator slot, 11t...stator tooth, 15...stator winding, 21...bearing, 22...bearing bracket, 23...frame, 100...rotor, 101...magnetic pole, 110...rotor shaft, 120...rotor core, 120a...outer core portion, 120b...inner core portion, 120f...flux barrier band, 120s...rotor core outer surface, 121...electromagnetic steel sheet, 122...deformed electromagnetic steel sheet, 123a...deformed first electromagnetic steel sheet, 123b...deformed second electromagnetic steel sheet, 125, 125r, 125s, 126, 127...laminated body, 130...wide-angle flux barrier band, 130a...wide-angle FBB opening, 131...permanent magnet storage hole, 132...wide-angle FBB first opening , 132a...first wall of wide-angle FBB first opening, 132b...second wall of wide-angle FBB first opening, 133...second wide-angle FBB opening, 133a...first wall of wide-angle FBB second opening, 133b...second wall of wide-angle FBB second opening, 135...central flux barrier, 135a, 135b...center bridge, 140...narrow-angle flux barrier band, 140a...narrow-angle FBB opening, 142...narrow-angle FBB first opening, 142a...first wall of narrow-angle FBB first opening, 142b...second wall of narrow-angle FBB first opening, 143...narrow-angle FBB second opening, 143a...first wall of narrow-angle FBB second opening, 143b...second wall of narrow-angle FBB second opening, 150...common opening, 152...first common opening, 153...second common opening, 160...permanent magnet

Claims

1. a rotor shaft extending in the axial direction of the central rotation axis; a plurality of permanent magnets extending in the axial direction and arranged equally in the circumferential direction and symmetrically with respect to a d-axis extending from the rotation central axis when viewed in a cross section perpendicular to the rotation central axis; a rotor core having a plurality of electromagnetic steel plates attached to the radial outside of the rotor shaft and laminated so that the d-axes overlap in the axial direction, accommodating a plurality of the permanent magnets, and having either a wide-angle flux barrier band or a narrow-angle flux barrier band formed in a substantially convex shape toward the central axis of rotation, including non-magnetic regions and bridges in magnetic poles that are divided circumferential angle regions; A rotor comprising: the wide-angle flux barrier band has a wide-angle FBB opening communicating with the outer circumferential surface of the rotor core, the narrow-angle flux barrier band has a narrow-angle FBB opening communicating with the outer circumferential surface of the rotor core, The inclined angle formed by the wall surface near the d-axis forming the wide-angle FBB opening and the tangent extending from the rotation center axis is defined as an inclined angle Θ １ａ The inclined angle Θ is defined as the inclined angle formed by the wall surface farther from the d-axis that forms the wide-angle FBB opening and the tangent line extending from the rotation center axis. １ｂ The inclined angle formed by the wall surface near the d-axis forming the narrow-angle FBB opening and the tangent extending from the rotation center axis is defined as the inclined angle Θ ２ａ The inclined angle Θ is defined as the inclined angle formed by the wall surface farther from the d-axis forming the narrow-angle FBB opening and the tangent line extending from the rotation center axis. ２ｂ When The inscribed angle Θ １ａ is the inscribed angle Θ ２ａ The larger the inscribed angle Θ １ｂ is the inscribed angle Θ ２ｂ and the inclination angle Θ １ｂ is the inscribed angle Θ １ａ The larger the inscribed angle Θ ２ｂ is the inscribed angle Θ ２ａ A rotor characterized by being larger.

2. The inscribed angle Θ １ａ and the inscribed angle Θ １ｂ The difference between the opening angle Θ １ｗ , the opening angle Θ １ｗ The width corresponding to the opening width w １ and the inclined angle Θ ２ａ and the inscribed angle Θ ２ｂ The difference between the opening angle Θ ２ｗ , the opening angle Θ ２ｗ The width corresponding to the opening width w ２ and the inclined angle Θ ２ｂ and the inscribed angle Θ １ａ The difference between the two angles is defined as a common aperture angle ΔΘ, and the width corresponding to the common aperture angle ΔΘ is defined as a common aperture width d. When the thickness of each of the plurality of electromagnetic steel plates is t, the opening width w １ and the opening width w ２ is greater than 2t, and the common aperture width d is greater than 0 and less than 2t; 2. The rotor according to claim 1 .

3. When n is a natural number that is equal to or greater than 1 and equal to or less than half the number of magnetic poles, In each of the plurality of electromagnetic steel plates, n magnetic poles on which the wide-angle flux barrier bands are formed and n magnetic poles on which the narrow-angle flux barrier bands are formed are alternately arranged in the circumferential direction, 2. The rotor according to claim 1, wherein two adjacent electromagnetic steel sheets among the plurality of electromagnetic steel sheets are shifted from each other in the circumferential direction by an amount corresponding to the n magnetic poles.

4. A rotor according to any one of claims 1 to 3; a stator disposed radially outside the rotor core; two bearings that rotatably support the rotor shaft; A rotating electric machine comprising:

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