Rotary electric machine

Abstract

To provide a rotary electric machine that can concentrate more magnetic fluxes on a magnetic pole without reducing strength of a rotor in comparison with prior arts.SOLUTION: A rotary electric machine includes a rotor that is rotatable around a rotation axis. The rotor has a plurality of salient poles, a pair of first magnetic flux deflection parts, a pair of second magnetic flux deflection parts, a magnet insertion hole, and a magnetic pole. The salient poles protrude outward in a radial direction of the rotor. In the first magnetic flux deflection parts, a pair of holes are formed extending in the radial direction of the rotor in both ends of each of the salient poles in a circumferential direction of the rotor. In the second magnetic flux deflection parts, a hole is formed so as to be provided between the pair of first magnetic flux deflection parts, spaced apart from each other in the circumferential direction of the rotor, and formed in a position with a part extending in the radial direction of the rotor and another part overlapping with the holes of the pair of first magnetic flux deflection parts in the circumferential direction of the rotor. The magnet insertion hole is provided on a radial outer side of the rotor to the pair of first magnetic flux deflection parts, communicating with the holes of the first magnetic flux deflection parts.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a rotating electrical machine.

Background Art

[0002] As a drive motor mounted on an electric vehicle such as a hybrid vehicle (HV) or an electric vehicle (EV), an interior permanent magnet synchronous motor (IPMSM) is widely known. A variable flux motor, which is a type of interior permanent magnet synchronous motor, can change the magnetization state of magnetic poles according to the motor speed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Compared with a general interior permanent magnet synchronous motor, a variable flux motor needs to concentrate more magnetic flux on the magnetic poles. By providing a flux barrier portion, which is a gap, in the rotor, more magnetic flux can be concentrated on the magnetic poles. However, if the flux barrier portion is provided over a wide range, the rigidity of the rotor may decrease, and the strength of the rotor may also decrease.

[0005] An object of the present invention is to provide a rotating electrical machine capable of concentrating more magnetic flux on the magnetic poles without reducing the strength of the rotor as compared with the prior art.

Means for Solving the Problems

[0006] To achieve the above object, the rotating electrical machine according to the present invention includes a rotor rotatable about a rotating shaft. The rotor has a plurality of salient pole portions, a pair of first magnetic flux deflecting portions, a pair of second magnetic flux deflecting portions, a magnet insertion hole, and magnetic poles. The plurality of salient pole portions project outward in the radial direction of the rotor. A pair of first magnetic flux deflecting portions are formed with a pair of holes extending in the radial direction of the rotor at both ends of each of the plurality of salient pole portions in the circumferential direction of the rotor. A pair of second magnetic flux deflecting portions are provided between the pair of first magnetic flux deflecting portions, are spaced apart from each other in the circumferential direction of the rotor, partially extend in the radial direction of the rotor, and are formed with a pair of holes formed at positions where a part overlaps with the pair of first magnetic flux deflecting portions in the circumferential direction of the rotor. The magnet insertion hole is provided outside the rotor in the radial direction with respect to the pair of first magnetic flux deflecting portions and communicates with the holes of the first magnetic flux deflecting portions. The magnetic poles are embedded in the magnet insertion holes.

[0007] According to the above configuration, since the first magnetic flux deflecting portion and the second magnetic flux deflecting portion are provided at the ends of the salient pole portions in the circumferential direction of the rotor, it is possible to suppress the magnetic flux flowing from the adjacent salient pole portions from heading toward the ends of the salient pole portions in the circumferential direction of the rotor. Further, the first magnetic flux deflecting portion suppresses the magnetic flux flowing from the adjacent salient pole portions from heading outside the salient pole portions from the ends of the magnet insertion holes in the circumferential direction of the rotor. As a result, the rotating electrical machine can induce the magnetic flux flowing toward the magnetic poles in the salient pole portions and concentrate it on the magnetic poles.

[0008] Further, in the rotating electrical machine according to the present invention, the holes of the pair of second magnetic flux deflecting portions communicate with the outside of the rotor.

[0009] According to this configuration, the second magnetic flux deflecting portion suppresses the magnetic flux flowing from the adjacent salient pole portions from heading toward the ends of the salient pole portions in the circumferential direction of the rotor. As a result, the rotating electrical machine can induce the magnetic flux flowing toward the magnetic poles in the salient pole portions and concentrate it on the magnetic poles.

[0010] In the rotating electrical machine according to the present invention, the radial length of the rotor from the end of the salient pole portion on the inner side in the radial direction of the rotor to the end of the magnetic pole on the inner side in the radial direction of the rotor is defined as the reference length. The holes of the pair of first magnetic flux deflecting portions and the holes of the pair of second magnetic flux deflecting portions are formed at positions where a range in the radial direction of the rotor that is 20% or more of the reference length and less than the length of the holes of the first magnetic flux deflecting portions overlaps in the circumferential direction of the rotor.

[0011] In the rotating electrical machine according to the present invention, the length of the holes of the pair of first magnetic flux deflecting portions in the radial direction of the rotor is 30% or more of the reference length.

[0012] In the rotating electrical machine according to the present invention, the length of the holes of the pair of second magnetic flux deflecting portions in the radial direction of the rotor is 60% or more of the reference length and equal to or greater than the length of the holes of the pair of first magnetic flux deflecting portions in the radial direction of the rotor.

[0013] According to this configuration, the first magnetic flux deflecting portion suppresses the magnetic flux flowing from the adjacent salient pole portions from heading from the end of the salient pole portion in the circumferential direction of the rotor to the outside of the rotor. As a result, the rotating electrical machine can induce the magnetic flux flowing toward the magnetic pole in the salient pole portion and concentrate it on the magnetic pole.

[0014] In the rotating electrical machine according to the present invention, the pair of second magnetic flux deflecting portions includes an extending portion in which holes extending in the radial direction of the rotor are formed, and a releasing portion in which holes extending in a direction intersecting the extending portion are formed. The holes of the releasing portion communicate with the holes of the extending portion and the outside of the rotor. The outer angle formed by the holes of the extending portion and the holes of the releasing portion is 75 degrees or less.

[0015] According to this configuration, the second magnetic flux deflecting portion rectifies the magnetic flux flowing from the adjacent salient pole portions and suppresses the magnetic flux from heading toward the end of the salient pole portion in the circumferential direction of the rotor. As a result, the rotating electrical machine can induce the magnetic flux flowing toward the magnetic pole in the salient pole portion and concentrate it on the magnetic pole.

Advantages of the Invention

[0016] According to the present invention, the rotating electrical machine can concentrate more magnetic flux on the magnetic poles without reducing the strength of the rotor.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0018] [Embodiment] Hereinafter, with reference to the accompanying drawings, an embodiment of the rotating electrical machine 1 will be described in detail. The configuration of the embodiment described below, as well as the actions and results (effects) brought about by the configuration, are merely examples and are not limited to the description content below. In this specification, ordinal numbers are used only for distinguishing parts and members and do not indicate order or priority. Further, this embodiment is an example in which the rotating electrical machine of the present invention is applied to a variable magnetic flux motor.

[0019] Hereinafter, the outline and structure of the rotating electrical machine 1 according to this embodiment will be described. FIG. 1 is a cross-sectional view showing an example of the configuration of the rotating electrical machine 1 according to one embodiment.

[0020] The rotating electrical machine 1 is a variable flux motor capable of changing its own rotational characteristics by changing the magnetic flux of the permanent magnet provided in the rotor. The rotating electrical machine 1 is an example of an embedded magnet type synchronous motor in the present disclosure. The rotating electrical machine 1 is used, for example, as a drive motor mounted on an electric vehicle such as a hybrid vehicle or an electric vehicle. Note that the rotating electrical machine 1 may be an ISG (Integrated Starter Generator) that also serves as a starter and a generator.

[0021] The variable flux motor generates a rotating magnetic field inside the rotor by changing the magnitude and direction of the current flowing in the stator. Then, the variable flux motor magnetizes or demagnetizes the permanent magnet provided in the rotor by concentrating the magnetic flux generated by the rotating magnetic field and flowing inside the rotor, and changes the operating point of the permanent magnet. As a result, since the magnetic flux density of the permanent magnet changes, the torque and rotational characteristics of the variable flux motor change. More specifically, the variable flux motor exhibits, for example, higher torque at low rotation by increasing the magnetic flux density of the permanent magnet. Also, the variable flux motor improves the efficiency of the motor at high rotation, for example, by reducing the magnetic flux density of the permanent magnet.

[0022] As shown in FIG. 1, the rotating electrical machine 1 includes a stator 10 and a rotor 11. The stator 10 is a part that generates a force for rotating the rotor 11. A coil 101 is installed inside the stator 10.

[0023] The coil 101 has coils 101a, 101b, and 101c. The rotating electrical machine 1 is driven by flowing, for example, a three-phase alternating current through each of the coils 101a, 101b, and 101c built into the stator 10. Note that the number of phases of the alternating current flowing through the coil 101 is not limited.

[0024] The rotor 11 is rotatably installed inside the stator 10 with an air gap therebetween. The rotor 11 is rotatable about the rotation axis Ax1. The rotor 11 is formed of, for example, a copper plate. Inside the rotor 11, magnetic flux generated by a three-phase alternating current flowing through the coil 101 flows. Hereinafter, unless otherwise specified, the axial direction, the radial direction, and the circumferential direction are the axial direction, the radial direction, and the circumferential direction of the rotation axis Ax1, that is, the axial direction, the radial direction, and the circumferential direction of the rotor 11.

[0025] The rotor 11 has eight salient pole portions 111 that protrude radially outward. Each of the salient pole portions 111 is provided at intervals in the circumferential direction. Each of the eight salient pole portions 111 is formed in a substantially rectangular parallelepiped shape.

[0026] FIG. 2 is an enlarged cross-sectional view showing an enlarged view of the F2 portion in FIG. 1 in the salient pole portion 111 of the rotating electrical machine 1 of the above embodiment. As shown in FIG. 2, a magnet insertion hole 113 is formed inside the salient pole portion 111. The magnet insertion hole 113 is located at the end of the salient pole portion 111 on the radially outer side. The magnet insertion hole 113 penetrates the rotor 11 in the axial direction and extends in the circumferential direction. The rotating electrical machine 1 is provided with one magnet insertion hole 113 for one salient pole portion 111. That is, the rotating electrical machine 1 has eight magnet insertion holes 113.

[0027] A pair of permanent magnets 114, which are magnetic poles, are embedded in the magnet insertion hole 113. The pair of permanent magnets 114 form the same magnetic poles. For example, in one of the pair of permanent magnets 114, if an N pole is formed on the radially outer side and an S pole is formed on the radially inner side, the other permanent magnet 114 adjacent to the permanent magnet 114 also has an N pole formed on the radially outer side and an S pole formed on the radially inner side. The pair of permanent magnets 114 in FIG. 2 has an N pole formed on the radially outer side and an S pole formed on the radially inner side. The pair of permanent magnets 114 is an example of a magnetic pole.

[0028] Also, a pair of permanent magnets 114 each of two adjacent salient pole portions 111 form magnetic poles with different directions from each other. For example, in a pair of permanent magnets 114 of a certain salient pole portion 111, when an N pole is formed on the radially outer side and an S pole is formed on the radially inner side, in a pair of permanent magnets 114 of another salient pole portion 111 adjacent to the salient pole portion 111, an S pole is formed on the radially outer side and an N pole is formed on the radially inner side.

[0029] The salient pole portion 111 has a pair of first flux barrier portions 116. A gap (hole) penetrating the rotor 11 in the axial direction is provided in the pair of first flux barrier portions 116. The pair of first flux barrier portions 116 are located at both ends of each of the salient pole portions 111 in the circumferential direction. That is, the pair of first flux barrier portions 116 are spaced apart from each other in the circumferential direction. The gaps provided in each of the pair of first flux barrier portions 116 extend in the radial direction. The magnet insertion hole 113 is provided radially outside the pair of first flux barrier portions 116. Each of the pair of first flux barrier portions 116 communicates with the magnet insertion hole 113. In the circumferential direction, a pair of permanent magnets 114 are provided between the pair of first flux barrier portions 116. Note that the gaps of the pair of first flux barrier portions 116 may be filled with a resin material so that the permanent magnets 114 are more reliably held with respect to the rotor 11. The first flux barrier portion 116 is an example of a first magnetic flux deflection portion.

[0030] The salient pole portion 111 further has a pair of second flux barrier portions 117. The pair of second flux barrier portions 117 are voids (holes) that penetrate the rotor 11 in the axial direction. A part of the pair of second flux barrier portions 117 is provided between the pair of first flux barrier portions 116. The pair of second flux barrier portions 117 are spaced apart from each other in the circumferential direction. A part of the pair of second flux barrier portions 117 extends in the radial direction. The voids of the pair of first flux barrier portions 116 and the voids of the pair of second flux barrier portions 117 are formed at positions where a part of each overlaps in the circumferential direction. The voids of the pair of second flux barrier portions 117 communicate with the outside of the rotor 11. The second flux barrier portion 117 is an example of a second magnetic flux deflection portion.

[0031] The pair of second flux barrier portions 117 have an extending portion 1171 and a releasing portion 1172. The extending portion 1171 is a portion that extends in the radial direction in the pair of second flux barrier portions 117. The releasing portion 1172 is a portion that extends in a direction intersecting the extending portion 1171 in the pair of second flux barrier portions 117. The void of the releasing portion 1172 communicates with the void of the extending portion 1171 and the outside of the rotor 11. In other words, the void of the extending portion 1171 communicates with the outside of the rotor 11 through the void of the releasing portion 1172.

[0032] The voids of the pair of first flux barrier portions 116 and the voids of the pair of second flux barrier portions 117 have a low magnetic permeability. In other words, the voids of the pair of first flux barrier portions 116 and the voids of the pair of second flux barrier portions 117 have a high magnetic resistance. Therefore, the magnetic flux that flows inside the rotor 11 and reaches the pair of first flux barrier portions 116 and the pair of second flux barrier portions 117 hardly passes through the inside of the pair of first flux barrier portions 116 and the pair of second flux barrier portions 117. The voids of the pair of first flux barrier portions 116 and the voids of the pair of second flux barrier portions 117 utilize the property of being difficult to pass such magnetic flux to control the direction of the magnetic flux inside the rotor 11.

[0033] The pair of first flux barrier portions 116 and the pair of second flux barrier portions 117 concentrate the magnetic flux generated by the current flowing through the coil 101 installed in the stator 10 and flowing inside the rotor 11 to the permanent magnet 114, and induce it to pass through the permanent magnet 114 toward the radially outer side. Details thereof will be described later.

[0034] (Shape and layout of the flux barrier portion) Next, with reference to FIG. 2, the shape and layout of the pair of first flux barrier portions 116 and the pair of second flux barrier portions 117 provided in the rotating electrical machine 1 will be described.

[0035] In FIG. 2, the magnet insertion holes 113, the pair of permanent magnets 114, the pair of first flux barrier portions 116, and the pair of second flux barrier portions 117 are arranged symmetrically with respect to the d-axis ad1. In the present embodiment, the d-axis Ad1 indicates an axis set in the direction (radial direction) of the magnetic poles of the rotor 11.

[0036] In FIG. 2, the radial distance from the end of the salient pole portion 111 on the radially inner side to the end of the permanent magnet 114 on the radially inner side is L0. Hereinafter, the distance L0 is referred to as the reference length. The radial length of the gap of the first flux barrier portion 116 is L1, and the length is 30 percent or more of the reference length.

[0037] In the circumferential direction, the radial length of the overlapping portion of the gap of the first flux barrier portion 116 and the gap of the second flux barrier portion 117 is L2. The length of the length L2 is 20 percent or more of the reference length and less than the radial length of the first flux barrier portion 116.

[0038] The radial length of the gap of the second flux barrier portion 117 is L3. The length L3 is 60 percent or more of the reference length and not less than the radial length of the first flux barrier portion 116.

[0039] The distance between the end of the salient pole portion 111 and the end of the gap of the first flux barrier portion 116 in the circumferential direction is L4. In other words, the distance L4 is the thickness of the salient pole portion 111 at the end of the salient pole portion 111 in the circumferential direction.

[0040] The distance between the gap of the first flux barrier portion 116 and the gap of the second flux barrier portion 117 is L5. In other words, the distance L5 is the thickness of the salient pole portion 111 between the gap of the first flux barrier portion 116 and the gap of the second flux barrier portion 117.

[0041] The distance between the permanent magnet 114 and the gap of the second flux barrier portion 117 in the radial direction is L6. In other words, the distance L6 is the radial thickness of the salient pole portion 111 between the permanent magnet 114 and the gap of the second flux barrier portion 117.

[0042] The outer angle formed by the gap of the extending portion 1171 and the gap of the releasing portion 1172 is θ1, and its magnitude is 75 degrees or less. In other words, the gap of the releasing portion 1172 is inclined with respect to the gap of the extending portion 1171 within a range of 75 degrees or less. When the angle θ1 is 75 degrees or less, the magnetic flux flowing from the adjacent salient pole portion 111 mainly travels toward the permanent magnet 114 along the periphery of the releasing portion 1172. For this reason, the rotating electrical machine 1 can induce and concentrate the magnetic flux flowing from the adjacent salient pole portion 111 into the permanent magnet 114 at a certain salient pole portion 111.

[0043] A plurality of R chamfers R1 are provided on the respective peripheries of the gaps of the pair of first flux barrier portions 116 and the gaps of the pair of second flux barrier portions 117. The size of each of the plurality of R chamfers R1 is 1 mm or more. The R chamfer R1 suppresses a decrease in the strength of the rotor 1 by concentrating stress of a magnitude corresponding to the rotational speed of the rotor 1 on the respective peripheries of the gaps of the pair of first flux barrier portions 116 and the gaps of the pair of second flux barrier portions 117 when the rotor 1 rotates about the rotation axis Ax1.

[0044] Here, the effect of suppressing the strength reduction of the rotor 11 by the R chamfering R1 will be described. When no R chamfering is provided at the periphery of each of the gaps of the pair of first flux barrier portions 116 and the gaps of the pair of second flux barrier portions 117, corners (not shown) are formed at the periphery of each of the gaps of the pair of first flux barrier portions 116 and the gaps of the pair of second flux barrier portions 117. This corner is the boundary between the rotor 11 and the gaps of the first flux barrier portion 116 and the gaps of the second flux barrier portion 117. Therefore, when the rotor 11 rotates about the rotation axis Ax1, a larger stress is applied to this corner than to other locations. The stress applied to this corner may be a factor that reduces the strength of the rotor 11.

[0045] On the other hand, when a plurality of R chamfers R1 are provided at the periphery of each of the gaps of the pair of first flux barrier portions 116 and the gaps of the pair of second flux barrier portions 117, and the size of each of the plurality of R chamfers R1 is 1 mm or more, the rotating electrical machine 1 can suppress the concentration of stress applied to the periphery of each of the gaps of the pair of first flux barrier portions 116 and the gaps of the pair of second flux barrier portions 117 during the rotation of the rotor 11. That is, the rotating electrical machine 1 can have the pair of first flux barrier portions 116 and the pair of second flux barrier portions 117 without reducing the strength of the rotor 11 during the rotation of the rotor 11.

[0046] (Magnetic Flux Flow and Magnetic Flux Concentration Effect in a Rotating Electrical Machine) Next, with reference to FIGS. 3 and 4, the magnetic flux flow and the magnetic flux concentration effect in the rotating electrical machine 1 will be described. FIG. 3 is a diagram for explaining an example of the magnetic flux flow in the F3 portion of FIG. 1 in the rotating electrical machine 1 of the above embodiment.

[0047] As an example of the magnetic flux flow, first, the magnetic flux generated by the three-phase alternating current flowing through the coil 101 passes through the vicinity of the permanent magnet 114a provided in the salient pole portion 111a shown in FIG. 3 and radially inward, and reaches the permanent magnet 114b provided in the adjacent salient pole portion 111b. The path will be described. In the following description, in order to distinguish each salient pole portion 111 and the components included in the salient pole portion 111, any one of the symbols a to c may be attached to the components.

[0048] The magnetic flux that has passed through the vicinity of the permanent magnet 114a provided in the salient pole portion 111a travels radially inward inside the salient pole portion 111a along the outer edge of each one of the pair of first flux barrier portions 116a and the pair of second flux barrier portions 117a disposed radially inward of the permanent magnet 114a and close to the salient pole portion 111b. Then, the magnetic flux traveling radially inward inside the salient pole portion 111a bypasses the space between the salient pole portion 111a and the salient pole portion 111b adjacent to the salient pole portion 111a and heads toward the salient pole portion 111b (arrow A1).

[0049] Furthermore, one of the pair of second flux barrier portions 117b provided in the salient pole portion 111b and close to the salient pole portion 111a induces the magnetic flux flowing from the salient pole portion 111a to one of the pair of permanent magnets 114b close to the salient pole portion 111a. At this time, the second flux barrier portion 117b suppresses the magnetic flux flowing from the salient pole portion 111a from heading toward the end portion of the salient pole portion 111b close to the salient pole portion 111a in the circumferential direction (arrow B1).

[0050] Also, one of the pair of first flux barrier portions 116b provided in the salient pole portion 111b and close to the salient pole portion 111a suppresses the magnetic flux flowing from the salient pole portion 111a from heading outside the rotor 11 from the vicinity of the end portion of the magnet insertion hole 113 close to the salient pole portion 111a in the circumferential direction (arrow C1).

[0051] Next, an explanation will be given regarding the path of the magnetic flux generated by the three-phase alternating current flowing through the coil 101, which passes through the permanent magnet 114c provided in the salient pole portion 111c adjacent to the salient pole portion 111b and near the permanent magnet 114c toward the radially inner side, and reaches the permanent magnet 114b provided in the salient pole portion 111b.

[0052] The magnetic flux that has passed near the permanent magnet 114c provided in the salient pole portion 111c travels radially inward within the salient pole portion 111c along the outer edge of each one of the pair of first flux barrier portions 116c and the pair of second flux barrier portions 117c that are disposed radially inside the permanent magnet 114c and are closer to the salient pole portion 111b. Then, the magnetic flux traveling radially inward within the salient pole portion 111c detours through the space between the salient pole portion 111c and the salient pole portion 111b and heads toward the salient pole portion 111b (arrow A2).

[0053] Furthermore, one of the pair of second flux barrier portions 117b provided in the salient pole portion 111b that is closer to the salient pole portion 111c induces the magnetic flux flowing from the salient pole portion 111c to one of the pair of permanent magnets 114b that is closer to the salient pole portion 111c. At this time, the second flux barrier portion 117b suppresses the magnetic flux flowing from the salient pole portion 111c from heading toward the end portion of the salient pole portion 111b closer to the salient pole portion 111c in the circumferential direction (arrow B2).

[0054] Also, one of the pair of first flux barrier portions 116b provided in the salient pole portion 111b that is closer to the salient pole portion 111c suppresses the magnetic flux flowing from the salient pole portion 111c from heading outside the rotor 11 from the vicinity of the end portion of the magnet insertion hole 113 closer to the salient pole portion 111c in the circumferential direction (arrow C2).

[0055] In this way, the pair of first flux barrier portions 116b and the pair of second flux barrier portions 117b induce the magnetic flux generated by the three-phase alternating current flowing through the coil 101 and flowing radially outward in the salient pole portion 111b to the pair of permanent magnets 114b. Depending on the arrangement of the coils 101a, 101b, and 101c of the coil 101, the direction of the generated magnetic flux may be opposite to that of the present embodiment. In that case, the generated magnetic flux travels in the opposite directions of the arrows A1 and A2.

[0056] Next, with reference to FIGS. 3 and 4, the effect of magnetic flux concentration on the permanent magnet 114b will be described. FIG. 4 is a graph showing the relationship between the external magnetic field and the magnetic flux density in the rotating electrical machine 1 of the present embodiment. As shown in FIG. 3, when the magnetic flux generated by the three-phase alternating current flowing through the coil 101 is induced to the permanent magnet 114b by the pair of first flux barrier portions 116b and the pair of second flux barrier portions 117b, a higher external magnetic field is concentrated on the permanent magnet 114b. Then, the magnetic flux density of the permanent magnet 114b increases, and the permanent magnet 114b is magnetized (arrow M1 in FIG. 4).

[0057] At this time, an external magnetic field close to the full magnetization magnetic field is applied to the permanent magnet 114b. For this reason, the rotating electrical machine 1 has a higher magnetic flux density of the permanent magnet 114b during magnetization (arrow M2) than a rotating electrical machine including a rotor of a conventional shape that does not have the pair of first flux barrier portions 116b and the pair of second flux barrier portions 117b. In this way, by having the pair of first flux barrier portions 116b and the pair of second flux barrier portions 117b, the rotating electrical machine 1 can apply an external magnetic field equivalent to the full magnetization magnetic field to the permanent magnet 114b, and can improve the magnetic flux density of the permanent magnet 114b during magnetization.

[0058] (Comparative Example) Next, a comparative example of the rotating electrical machine 1 will be described. FIG. 5 is an enlarged cross-sectional view showing the salient pole portion 111A of the rotating electrical machine 1A according to the comparative example of the present embodiment. As shown in FIG. 5, the salient pole portion 111A included in the rotor 11A of the rotating electrical machine 1A in the comparative example does not have a pair of first flux barrier portions 116, but has a pair of second flux barrier portions 117A. Since the other configurations are the same as those of the rotating electrical machine 1 of the present embodiment, the same reference numerals are assigned to the equivalent configurations, and the description thereof will be omitted. Further, in the pair of permanent magnets 114 in FIG. 5, N poles are formed on the radially outer side and S poles are formed on the radially inner side.

[0059] Unlike the pair of second flux barrier portions 117 in the rotating electrical machine 1, the pair of second flux barrier portions 117A in the rotating electrical machine 1A are integrated with the outside of the rotor 11A. That is, the pair of second flux barrier portions 117A form a concave shape facing the d-axis Ad1 with respect to the salient pole portion 111A, rather than a gap.

[0060] The pair of second flux barrier portions 117A guide the magnetic flux flowing radially outward of the salient pole portion 111A to the pair of permanent magnets 114. After the magnetic flux induced by the pair of second flux barrier portions 117A passes through the second flux barrier portions 117A, a part of the magnetic flux leaks from the end portions of the salient pole portion 111A in the circumferential direction to the outside of the rotor 11A (arrows C1 and C2).

[0061] On the other hand, as described above, the salient pole portion 111 in the rotating electrical machine 1 of the present embodiment has a pair of first flux barrier portions 116. Therefore, leakage of a part of the magnetic flux flowing radially outward of the salient pole portion 111 from the vicinity of the end portions of the magnet insertion holes 113 in the circumferential direction to the outside of the rotor 11 is suppressed.

[0062] As described above, the rotating electrical machine 1 of the present embodiment has a pair of first flux barrier portions 116 in the salient pole portion 111, thereby suppressing the magnetic flux leaking to the outside of the rotor 11, and thus concentrating the magnetic flux on the permanent magnets 114.

[0063] In the above-described embodiment, the rotating electrical machine 1 includes a rotor 11 that is rotatable about a rotation axis Ax1. The rotor 11 has a plurality of salient pole portions 111, a pair of first flux barrier portions 116, a pair of second flux barrier portions 117, magnet insertion holes 113, and permanent magnets 114. The plurality of salient pole portions 111 project outward in the radial direction. A pair of first flux barrier portions 116 are formed with gaps (holes) extending in the radial direction at both ends of each of the plurality of salient pole portions 111 in the circumferential direction. A pair of second flux barrier portions 117 are partially provided between the pair of first flux barrier portions 116, are spaced apart from each other in the circumferential direction, partially extend in the radial direction, and are formed with gaps that partially overlap the gaps of the pair of first flux barrier portions 116 in the circumferential direction. The magnet insertion holes 113 are provided radially outside the pair of first flux barrier portions 116 and communicate with the gaps of the pair of first flux barrier portions 116. The permanent magnets 114 are embedded in the magnet insertion holes 113.

[0064] In the above-described configuration, the pair of second flux barrier portions 117b suppress the magnetic flux flowing from the salient pole portion 111a adjacent to the salient pole portion 111b from heading toward the end portion of the salient pole portion 111b in the circumferential direction. Also, the pair of first flux barrier portions 116b suppress the magnetic flux flowing from the salient pole portion 111a from heading outside the rotor 11 from the end portion of the magnet insertion hole 113 in the circumferential direction. As a result, the rotating electrical machine 1 can induce the magnetic flux flowing toward the permanent magnet 114 in each of the eight salient pole portions 111 and concentrate it on the permanent magnet 114.

[0065] Also, in the present embodiment, the gaps of the pair of second flux barrier portions 117 communicate with the outside of the rotor 11.

[0066] In the above configuration, the pair of second flux barrier portions 117b suppress the magnetic flux flowing from the salient pole portion 111a adjacent to the salient pole portion 111b from heading toward the end portion of the salient pole portion 111b in the circumferential direction. As a result, the rotating electrical machine 1 can induce the magnetic flux flowing toward the permanent magnet 114 in each of the eight salient pole portions 111 and concentrate it on the permanent magnet 114.

[0067] Also, in the present embodiment, the radial length from the end portion of the salient pole portion 111 on the radially inner side to the end portion of the permanent magnet 114 on the radially inner side is defined as the reference length, and the gaps of the pair of first flux barrier portions 116 and the gaps of the pair of second flux barrier portions 117 are formed at positions where the range that is 20% or more of the reference length and less than the length of the gaps of the pair of first flux barrier portions 116 in the radial direction overlaps in the circumferential direction.

[0068] Also, in the present embodiment, the length of the gaps of the pair of first flux barrier portions 116 in the radial direction is 30% or more of the reference length.

[0069] Also, in the present embodiment, the length of the gaps of the pair of second flux barrier portions 117 in the radial direction is 60% or more of the reference length and not less than the length of the gaps of the pair of first flux barrier portions 116 in the radial direction.

[0070] In the above configuration, the pair of first flux barrier portions 116b provided in the salient pole portion 111b suppress the magnetic flux flowing from the salient pole portion 111a adjacent to the salient pole portion 111b from leaking to the outside of the rotor 11 from the vicinity of the end portion of the magnet insertion hole 113 in the circumferential direction. As a result, the rotating electrical machine 1 can induce the magnetic flux flowing toward the permanent magnet 114 in each of the eight salient pole portions 111 and concentrate it on the permanent magnet 114.

[0071] Also, in the present embodiment, the pair of second flux barrier portions 117 has an extending portion 1171 in which a void (hole) extending in the radial direction is formed, and a releasing portion 1172 in which a void extending in a direction intersecting the extending portion 1171 is formed. The void in the releasing portion 1172 communicates with the void in the extending portion and the outside of the rotor. The outer angle formed by the void in the extending portion 1171 and the void in the releasing portion 1172 is 75 degrees or less.

[0072] In the above configuration, the pair of second flux barrier portions 117b provided in the salient pole portion 111b rectify the magnetic flux flowing from the adjacent salient pole portion 111a and suppress the magnetic flux from heading toward the end of the salient pole portion 111b in the circumferential direction. As a result, the rotating electrical machine 1 can induce the magnetic flux flowing toward the permanent magnet 114 in each of the eight salient pole portions 111 and concentrate it on the permanent magnet 114.

[0073] Although the embodiments of the present invention have been described above, the above-described embodiments are presented as examples and are not intended to limit the scope of the present invention. This novel embodiment can be implemented in various other forms. Also, various omissions, replacements, and changes can be made without departing from the gist of the invention. Further, this embodiment is included in the scope and gist of the invention and is included in the invention described in the claims and the equivalent scope thereof.

Description of Reference Numerals

[0074] 1, 1A Rotating Electrical Machine 11, 11A Rotor 111, 111a, 111b, 111c, 111A Salient Pole Portion 113 Magnet Insertion Hole 114, 114a, 114b, 114c Permanent Magnet 116, 116a, 116b, 116c First Flux Barrier Portion 117, 117a, 117b, 117c, 117A Second Flux Barrier Portion 1171 Extending Portion 1172 Releasing Portion Ax1 Rotation Axis Radial distance (reference length) from the end of the salient pole portion on the inner side of the L0 diameter direction to the end of the permanent magnet on the inner side of the diameter direction Radial length of the gap of the first flux barrier portion L1 Radial length of the portion where the gap of the first flux barrier portion and the gap of the second flux barrier portion overlap in the circumferential direction L2 Radial length of the gap of the second flux barrier portion L3 Distance between the end of the salient pole portion and the gap of the first flux barrier portion in the circumferential direction L4 Distance between the gap of the first flux barrier portion and the gap of the second flux barrier portion L5 Distance between the permanent magnet and the gap of the second flux barrier portion in the radial direction L6 Outer angle formed by the gap of the extending portion and the gap of the releasing portion θ1 R chamfer provided at the periphery of the gap of the first flux barrier portion and the gap of the second flux barrier portion R1

Claims

1. A stator, A rotor provided on the radially inner side of the stator and rotatable about a rotation axis, In a rotating electrical machine comprising: The rotor is A plurality of salient pole portions protruding toward the radially outer side of the rotor, A pair of first magnetic flux deflecting portions in which holes extending in the radial direction of the rotor are formed at both ends of each of the plurality of salient pole portions in the circumferential direction of the rotor, A part is provided between the pair of first magnetic flux deflecting portions, separated from each other in the circumferential direction of the rotor, a part extends in the radial direction of the rotor, and holes are formed at positions where a part overlaps with the holes of the pair of first magnetic flux deflecting portions in the circumferential direction of the rotor. A pair of second magnetic flux deflecting portions, A magnet insertion hole provided on the radially outer side of the rotor with respect to the pair of first magnetic flux deflecting portions and communicating with the holes of the first magnetic flux deflecting portions, A magnetic pole embedded in the magnet insertion hole, A rotating electrical machine having.

2. The holes of the pair of second magnetic flux deflecting portions communicate with the outside of the rotor, The rotating electrical machine according to claim 1.

3. The length in the radial direction of the rotor from the end of the salient pole portion on the radially inner side of the rotor to the end of the magnetic pole on the radially inner side of the rotor is defined as a reference length, The holes of the pair of first magnetic flux deflecting portions and the holes of the pair of second magnetic flux deflecting portions are formed at positions where a range of 20% or more of the reference length and less than the length of the holes of the first magnetic flux deflecting portions in the radial direction of the rotor overlaps in the circumferential direction of the rotor. The rotating electrical machine according to claim 2.

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