Rotating electric machine

Abstract

Provided is a rotating electrical machine in which an increase in eddy current in the rotating electrical machine can be suppressed and the loss of a coil can be greatly reduced. The rotating electrical machine includes: a stator having a coil and a first magnetic core; and a rotor having a permanent magnet and a second magnetic core. The rotating electrical machine is provided with a magnetic structure that is provided to at least one of two coil end portions, which are both ends of the coil, and that guides magnetic flux from the second magnetic core toward the first magnetic core. Here, the magnetic structure guides magnetic flux from the second magnetic core to the first magnetic core in the radial direction of the rotating electrical machine, and guides magnetic flux from the second magnetic core to the first magnetic core in the circumferential direction of the rotating electrical machine. In addition, the magnetic structure is provided so that the magnetic flux and the coil do not substantially interlink with each other.

Description

Technical Field

[0001] The present disclosure relates to rotating electrical machines (also referred to as rotating machines) such as motors, generators, and the like. Background Art

[0002] For example, Patent Document 1 describes a comparative slotless rotating machine. To address the issue of low inductance in the stator windings of the slotless rotating machine, the PWM control method utilizes the winding's inductance component, specifically the first-order lag characteristics of the current, to continuously apply a pulsed voltage to control the current value, thereby making it appear as a continuous sinusoidal current. To address this issue, the invention of Patent Document 1 is characterized by providing a soft magnetic member at the coil end to increase the winding's leakage inductance.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2020-061853 Summary of the Invention

[0006] These rotating electrical machines have a problem of increased coil loss at the coil end portion of the stator winding. This coil loss is caused by eddy current, and the following factors are considered to be the main cause of the increase in eddy current.

[0007] (1) The frequency of the current flowing through the stator winding is increased, and the rotation speed is increased.

[0008] (2) Increase in induced electromotive force (electromotive force of eddy current) caused by leakage magnetic flux at the coil end portion.

[0009] (3) Increase in leakage magnetic flux at the coil end due to miniaturization.

[0010] An object of the present disclosure is to provide a rotating electrical machine capable of suppressing an increase in eddy current in the rotating electrical machine and significantly reducing coil loss.

[0011] A rotating electrical machine according to one embodiment of the present disclosure includes: a stator having a coil and a first magnetic core; and a rotor having a permanent magnet and a second magnetic core.

[0012] This rotating electrical machine includes a magnetic structure provided at at least one of two coil end portions serving as both ends of the coil, and guiding magnetic flux from the second magnetic core toward the first magnetic core.

[0013] In the rotating electric machine, the magnetic structure guides the magnetic flux from the second magnetic core toward the first magnetic core in the radial direction of the rotating electric machine and guides the magnetic flux from the second magnetic core toward the first magnetic core in the circumferential direction of the rotating electric machine.

[0014] Furthermore, in the rotating electrical machine, the magnetic structure is provided so that the magnetic flux does not substantially interlink with the coil.

[0015] Therefore, according to one embodiment of the present invention, the rotating motor can reduce the eddy current loss in the coil by suppressing the increase of the induced electromotive force (electromotive force of eddy current) caused by the leakage magnetic flux at the end of the coil and the increase of the leakage magnetic flux at the end of the coil due to miniaturization, thereby significantly reducing the loss of the coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1A It is a perspective view showing the appearance of a rotating electrical machine according to a comparative example.

[0017] Figure 1B Yes Figure 1A 1 is a perspective view of the appearance of the stator 10.

[0018] Figure 1C Yes Figure 1A A perspective view of the appearance of the rotor 20.

[0019] Figure 2A yes Figure 1A A top view of a rotating electrical machine.

[0020] Figure 2B yes Figure 2A A longitudinal sectional view of the A-A' plane.

[0021] Figure 3A It means in Figure 1A A top view of the main magnetic flux lines flowing in the magnetic body in the rotating electrical machine.

[0022] Figure 3B It means in Figure 1A A longitudinal cross-sectional view of a rotating electrical machine showing magnetic flux lines leaking to the coil end portion and interlinking with the coil to generate eddy currents.

[0023] Figure 3C It means in Figure 1A A three-dimensional diagram of a rotating electrical machine showing how magnetic flux lines leaking toward the coil ends intersect with the coils and generate eddy currents.

[0024] Figure 4 It is a perspective view showing a structural example of one sector of the rotating electrical machine according to the first embodiment.

[0025] Figure 5A yes Figure 1A8 is a perspective view of one sector of the rotating electrical machine showing simulation results of the rotating electrical machine and a magnetic flux density vector 85 of magnetic flux lines leaking to the coil end portion when the rotor rotation angle is 0 degrees.

[0026] Figure 5B yes Figure 5A A perspective top view of the simulation results.

[0027] Figure 5C yes Figure 5A A perspective side view of the simulation results.

[0028] Figure 6A yes Figure 1A 8 is a perspective view of one sector of the rotating electrical machine showing simulation results of the rotating electrical machine and a magnetic flux density vector 86 of magnetic flux lines leaking to the coil end portion when the rotor has a rotation angle of 7.5 degrees.

[0029] Figure 6B yes Figure 6A A perspective top view of the simulation results.

[0030] Figure 6C yes Figure 6A A perspective side view of the simulation results.

[0031] Figure 7A yes Figure 1A 8 is a perspective view of one sector of the rotating electrical machine showing a simulation result of the rotating electrical machine and a magnetic flux density vector 87 of magnetic flux lines leaking to the coil end portion when the rotor has a rotation angle of 15 degrees.

[0032] Figure 7B yes Figure 7A A perspective top view of the simulation results.

[0033] Figure 7C yes Figure 7A A perspective side view of the simulation results.

[0034] Figure 8A yes Figure 1A 1 is a perspective view of one sector of the rotating electrical machine, showing simulation results of the rotating electrical machine and analysis results of eddy currents in the coils in the rotating magnetic field generated by the magnets of the rotor.

[0035] Figure 8B yes Figure 8A A perspective top view of the simulation results.

[0036] Figure 9A It is a perspective view showing the structure of one sector of a rotating electrical machine according to a comparative example.

[0037] Figure 9B This is a perspective view showing the structure of one sector of the rotating electrical machine according to the first embodiment.

[0038] Figure 10A yes Figure 9A The simulation results of a sector of a rotating motor are shown in Figure 1, and the current density is 1×10 when the rotor rotation angle is 0 degrees. 6 (A / m 2 ) is a stereogram of the distribution above.

[0039] Figure 10B yes Figure 10A A top view of the simulation results.

[0040] Figure 11A yes Figure 9A The simulation results of a sector of a rotating motor are shown in Figure 1, and the current density is 1×10 when the rotor rotation angle is 7.5 degrees. 6 (A / m 2 ) is a stereogram of the distribution above.

[0041] Figure 11B yes Figure 11A A top view of the simulation results.

[0042] Figure 12A yes Figure 9A The simulation results of a sector of a rotating motor are shown in Figure 1, and the current density is 1×10 6 (A / m 2 ) is a stereogram of the distribution above.

[0043] Figure 12B yes Figure 12A A top view of the simulation results.

[0044] Figure 13A yes Figure 9B The simulation results of a sector of a rotating motor are shown in Figure 1, and the current density is 1×10 when the rotor rotation angle is 0 degrees. 6 (A / m 2 ) is a stereogram of the distribution above.

[0045] Figure 13B yes Figure 13A A top view of the simulation results.

[0046] Figure 14A yes Figure 9B The simulation results of a sector of a rotating motor are shown in Figure 1, and the current density is 1×10 when the rotor rotation angle is 7.5 degrees. 6 (A / m 2 ) is a stereogram of the distribution above.

[0047] Figure 14B yes Figure 14A A top view of the simulation results.

[0048] Figure 15A yes Figure 9B The simulation results of a sector of a rotating motor are shown in Figure 1, and the current density is 1×10 6 (A / m 2 ) is a stereogram of the distribution above.

[0049] Figure 15B yes Figure 15A A top view of the simulation results.

[0050] Figure 16A yes Figure 9A The simulation results of a rotating motor sector are shown in Figure 1, and the eddy current loss per unit area is 1×10 4 (W / m 3 ) is a stereogram of the distribution above.

[0051] Figure 16B yes Figure 9B The simulation results of a rotating motor sector are shown in Figure 1, and the eddy current loss per unit area is 1×10 4 (W / m 3 ) is a stereogram of the distribution above.

[0052] Figure 17A Yes Figure 9A A perspective view of the structure of one sector of a rotating electrical machine of a comparative example.

[0053] Figure 17B yes Figure 17A A top view of a rotating electrical machine.

[0054] Figure 17C yes Figure 17A Side view of a rotating electrical machine.

[0055] Figure 17D yes Figure 17A Front view of a rotating electrical machine.

[0056] Figure 18A Yes Figure 9B A perspective view of the structure of one sector of the rotating electrical machine according to embodiment 1.

[0057] Figure 18B yes Figure 18A A top view of a rotating electrical machine.

[0058] Figure 18C yes Figure 18A Side view of a rotating electrical machine.

[0059] Figure 18D yes Figure 18A Front view of a rotating electrical machine.

[0060] Figure 19A It is a perspective view showing the structure of one sector of the rotating electrical machine according to the second embodiment.

[0061] Figure 19B yes Figure 19A A top view of a rotating electrical machine.

[0062] Figure 19C yes Figure 19A Side view of a rotating electrical machine.

[0063] Figure 19D yes Figure 19A Front view of a rotating electrical machine.

[0064] Figure 20A It is a perspective view showing the structure of one sector of the rotating electrical machine according to the third embodiment.

[0065] Figure 20B yes Figure 20A A top view of a rotating electrical machine.

[0066] Figure 21A It is a perspective view showing the structure of one sector of the rotating electrical machine according to the fourth embodiment.

[0067] Figure 21B yes Figure 21A A top view of a rotating electrical machine.

[0068] Figure 22A It is a perspective view showing the structure of one sector of the rotating electrical machine according to the fifth embodiment.

[0069] Figure 22B yes Figure 22A A three-dimensional diagram of a magnetic structure of a rotating electrical machine.

[0070] Figure 22C yes Figure 22A A three-dimensional view of the magnetic structure of a rotating motor when it is turned upside down.

[0071] Figure 22D yes Figure 22A A top view of a rotating electrical machine.

[0072] Figure 23A It is a perspective view showing the structure of one sector of the rotating electrical machine according to the sixth embodiment.

[0073] Figure 23B yes Figure 23A A top view of a rotating electrical machine.

[0074] Figure 24AIt is a perspective view showing the structure of one sector of the rotating electrical machine according to the seventh embodiment.

[0075] Figure 24B yes Figure 24A A top view of a rotating electrical machine. DETAILED DESCRIPTION

[0076] Hereinafter, embodiments and modifications of the present disclosure will be described with reference to the accompanying drawings. The same or similar components are denoted by the same reference numerals.

[0077] (Opinion of the inventor)

[0078] (Comparative Example)

[0079] Figure 1A is a perspective view showing the appearance of a rotating electrical machine of a comparative example. Figure 1B Yes Figure 1A A perspective view of the appearance of the stator 10, Figure 1C Yes Figure 1A A perspective view of the appearance of the rotor 20. Figure 2A yes Figure 1A A top view of a rotating electrical machine, Figure 2B yes Figure 2A The details of the structure of one sector of the rotating electrical machine are shown in FIG. Figures 17A to 17D .

[0080] exist Figures 1A to 1C and Figure 2A-2B middle, Figure 1A The rotating motor is composed of Figure 1B The stator 10 and Figure 1C A slotless rotating electric machine with a rotor 20 is constructed by rotatably inserting the rotor 20 into the hollow core of a stator 10. The stator 10 includes, for example, 12 sectors 10C, each comprising a plurality of coils 12 formed of a conductor and a plurality of magnetic cores 11 formed of a magnetic material. The coils 12 have terminals 13 and 14, for example, protruding upward, at their ends. For example, 12 coils 12 are arranged cylindrically inside the stator 10. Outside the arranged 12 coils 12, for example, 24 magnetic cores 11 are arranged, with portions of the magnetic cores 11 inserted and fitting into the hollow cores of the roughly rectangular cylinders of the coils 12. Furthermore, the rotating shaft 21 of the rotor 20 is inserted into the hollow core of a cylindrical magnetic core 22. Twelve permanent magnets 23, for example, are arranged around the outer periphery of the magnetic core 22.

[0081] Here, the rotating electrical machine can be miniaturized by reducing the axial length L. Figure 3A and Figure 3B The following describes how the loss increases with this miniaturization.

[0082] Figure 3A It means in Figure 1A A top view of the main magnetic flux lines flowing in the magnetic body in the rotating electrical machine, Figure 3B It means in Figure 1A A longitudinal cross-sectional view of a rotating electrical machine showing the eddy currents generated by the magnetic flux lines leaking to the coil ends and interlinking with the coils. Figure 3C It means in Figure 1A A three-dimensional diagram of a rotating electrical machine showing how magnetic flux lines leaking toward the coil ends intersect with the coils and generate eddy currents.

[0083] exist Figure 3A , the main magnetic flux lines 91 flowing in the magnetic body of the magnetic core 11 are shown. Figure 3B and Figure 3C As can be seen, magnetic flux lines 91 leaking toward coil ends 12a and 12b (referred to as the vertical ends of coil 12) intersect with the coil, generating eddy currents. Specifically, as rotating electrical machines become smaller, the magnetic core 11 of stator 10 becomes smaller, making it more likely to reach magnetic saturation. Consequently, the amount of magnetic flux leaking toward the coil ends increases, leading to increased eddy current losses.

[0084] (Implementation 1)

[0085] Figure 4 This is a perspective view showing a structural example of a sector 10A of the rotating electrical machine according to the first embodiment, showing the details of the structure. Figures 18A to 18D . Figure 4 A sector 10A of a rotating electrical machine with Figure 3C Compared to a sector 10C of a rotating electric machine, a feature of the present invention is that magnetic structures 15A and 15B are provided at coil end portions 12a and 12b, respectively, to guide leakage magnetic flux so that it does not interlink with coil 12. While magnetic structures 15A and 15B may be provided in all sectors of the rotating electric machine, the present disclosure is not limited thereto and may be provided in only a portion of the sectors.

[0086] The magnetic structures 15A and 15B respectively include a flat base 115a extending in the radial and circumferential directions and legs 215b and 215c (bent in a manner opposite to the outer peripheral surface and the inner peripheral surface, respectively) extending in the upper and lower thickness directions (directions parallel to the axial direction of the rotating motor) connected to the two radial ends of the flat base 215a, thereby being constructed in a manner covering the coil end portions 12a and 12b of the coil 12 from above and below.

[0087] In the first embodiment, the magnetic core 11 is formed of a magnetic material such as an electromagnetic steel sheet, for example, silicon steel, and has a relative magnetic permeability of approximately 4,000 to 50,000. In the simulation, this relative magnetic permeability was set to 5,000. Furthermore, the magnetic structure 15 is formed of a pressed magnetic powder, for example, such as ferrite, and has a relative magnetic permeability of approximately 100 to 2,000. In the simulation, this relative magnetic permeability was set to 1,000.

[0088] exist Figure 4 In the embodiment, the magnetic flux lines generated by the permanent magnet 23 are directed toward the coil 12 as indicated by reference numeral 92. However, a portion of these magnetic flux lines leaks as indicated by magnetic flux lines 93. Specifically, the leaked magnetic flux lines 93 intersect with the coil 12 at the coil end portions 12a and 12b, generating eddy currents. Here, the configuration is such that the leaked magnetic flux lines 93 are guided by the magnetic structures 15A and 15B, which are magnetic materials with high magnetic permeability, so that the magnetic flux lines 93 do not substantially intersect with the coil 12.

[0089] In the rotating magnetic field of the rotating electrical machine configured as described above, it is considered necessary to have an effect of guiding leakage magnetic flux lines 93 in the radial direction 94 and an effect of guiding leakage magnetic flux lines 93 in the circumferential direction 95 .

[0090] Next, the results of simulations performed by the inventors are described below.

[0091] Figure 5A It is a comparative example Figure 1A The present invention is a perspective view of a sector of the rotating electrical machine showing a simulation result of the rotating electrical machine and a magnetic flux density vector 85 of magnetic flux lines leaking toward the coil end portions 15a and 15b when the rotor rotation angle is 0 degrees. Figure 5B yes Figure 5A A perspective top view of the simulation results, Figure 5C yes Figure 5A A perspective side view of the simulation results.

[0092] Figure 6A yes Figure 1A The present invention is a perspective view of a sector of a rotating electrical machine showing a simulation result of a rotating electrical machine and a magnetic flux density vector 86 of magnetic flux lines leaking toward coil end portions 15a and 15b when the rotor has a rotation angle of 7.5 degrees. Figure 6B yes Figure 6A A perspective top view of the simulation results, Figure 6C yes Figure 6A A perspective side view of the simulation results.

[0093] Figure 7A yes Figure 1AThe present invention is a perspective view of a sector of a rotating electrical machine showing a simulation result of a rotating electrical machine and a magnetic flux density vector 87 of magnetic flux lines leaking toward coil end portions 15a and 15b when the rotor rotates at a 15-degree angle. Figure 7B yes Figure 7A A perspective top view of the simulation results, Figure 7C yes Figure 7A A perspective side view of the simulation results.

[0094] exist Figures 5A to 5C 、 Figures 6A to 6C as well as Figures 7A to 7C 15a and 15b, respectively, and the simulation results of the magnetic flux density vectors 85 to 87 of the magnetic flux lines leaking to the coil end portions 15a and 15b are shown in time-resolved animation. As can be seen from these figures, the leakage magnetic flux is significant at the coil end portions 15a and 15b.

[0095] Figure 8A yes Figure 1A The present invention also provides a simulation result of a rotating electrical machine, and is a perspective perspective view of one sector of the rotating electrical machine showing an analysis result of eddy currents in the coils in the rotating magnetic field generated by the magnets of the rotor. Figure 8B yes Figure 8A A perspective top view of the simulation results.

[0096] exist Figure 8A and Figure 8B In FIG. 1 , the eddy current distribution in the coil 12 in the rotating magnetic field generated by the permanent magnet 23 of the rotor 20 is shown by hatching. Figure 8A and Figure 8B It can be seen that a great number of eddy currents are generated at the coil end portions 15a and 15b.

[0097] Figure 9A is a perspective view showing the structure of one sector of a rotating electrical machine of a comparative example, Figure 9B This is a perspective view showing the structure of one sector of the rotating electrical machine according to the first embodiment. Figure 9A In the rotary electric machine of the comparative example, leakage magnetic flux lines 91 are generated. Figure 9B In the rotating electrical machine of the first embodiment, the magnetic structure 15AA attached to the coil end portions 15a and 15b is connected to the magnetic structure 15AA. Figure 4 In comparison with the magnetic structure 15A, through holes 16 and 17 are formed that penetrate the magnetic structure 15AA in the vertical direction in order to make the terminals 13 and 14 protrude upward.

[0098] In the rotating electrical machine configured as described above, the leakage magnetic flux lines 93 generated above are guided and confined in the magnetic structure 15AA by the magnetic structure 15AA, thereby reducing the leakage magnetic flux lines 93 and significantly reducing eddy current losses.

[0099] Next, simulation results of current density distributions in the comparative example and the first embodiment are described below.

[0100] Figure 10A yes Figure 9A The simulation results of a sector of a rotating motor are shown in Figure 1, and the current density is 1×10 when the rotor rotation angle is 0 degrees. 6 (A / m 2 ) above the distribution of the three-dimensional diagram, Figure 10B yes Figure 10A Here, the current density distribution is represented by reference numeral 110 .

[0101] Figure 11A yes Figure 9A The simulation results of a sector of a rotating motor are shown in Figure 1, and the current density is 1×10 when the rotor rotation angle is 7.5 degrees. 6 (A / m 2 ) above the distribution of the three-dimensional diagram, Figure 11B yes Figure 11A Here, the current density distribution is represented by reference numeral 111.

[0102] Figure 12A yes Figure 9A The simulation results of a sector of a rotating motor are shown in Figure 1, and the current density is 1×10 6 (A / m 2 ) above the distribution of the three-dimensional diagram, Figure 12B yes Figure 12A Here, the current density distribution is represented by reference numeral 112 .

[0103] Figure 13A yes Figure 9B The simulation results of a sector of a rotating motor are shown in Figure 1, and the current density is 1×10 when the rotor rotation angle is 0 degrees. 6 (A / m 2 ) above the distribution of the three-dimensional diagram, Figure 13B yes Figure 13A Here, the current density distribution is represented by reference numeral 113 .

[0104] Figure 14A yes Figure 9B The simulation results of a sector of a rotating motor are shown in Figure 1, and the current density indicated by the monochrome contour line is 1×10 6 (A / m 2 ) above the distribution of the three-dimensional diagram, Figure 14B yes Figure 14AHere, the current density distribution is represented by reference numeral 114 .

[0105] Figure 15A yes Figure 9B The simulation results of a sector of a rotating motor are shown in Figure 1, and the current density is 1×10 6 (A / m 2 ) above the distribution of the three-dimensional diagram, Figure 15B yes Figure 15A Here, the current density distribution is represented by reference numeral 115 .

[0106] according to Figures 10A to 12B The simulation results of the comparative example show that in the comparative example without the magnetic structures 15A and 15B, the generated current density is 1×10 6 (A / m 2 ) above the current density distribution 110 ~ 112. In contrast, according to Figures 13A to 15B The simulation results of the first embodiment show that in the first embodiment including the magnetic structures 15A and 15B, there is no current density of 1×10 6 (A / m 2 ) and above current density distribution 113~115.

[0107] Next, simulation results of current density distributions in the comparative example and the first embodiment are described below.

[0108] Figure 16A yes Figure 9A The simulation results of a rotating motor sector are shown in Figure 1, and the eddy current loss per unit area is 1×10 4 (W / m 3 ) is a three-dimensional diagram of the distribution above, and the eddy current loss distribution is represented by the reference numeral 116A. In addition, Figure 16B yes Figure 9B The simulation results of a rotating motor sector are shown in Figure 1, and the eddy current loss per unit area is 1×10 4 (W / m 3 ) is a three-dimensional diagram of the distribution above, and its eddy current loss distribution is represented by the figure mark 116B.

[0109] Figure 16A The eddy current loss of the rotating electric machine of the comparative example is generated particularly at the coil end portions 15a, 15a. In contrast, it can be seen that: Figure 16B In the rotating electrical machine according to the first embodiment, eddy current loss is not generated at all, particularly at the coil end portions 15 a and 15 b .

[0110] As described above, according to the rotating electrical machine of the first embodiment, the guide rails are provided at the coil end portions 15a and 15b. Figure 18A The radial leakage flux 81 in the guide Figure 18A The magnetic structures 15A, 15AA, and 15B that prevent leakage magnetic flux in the circumferential direction 82 can significantly reduce leakage magnetic flux lines and eddy current losses at the coil end portions 15a and 15b compared to the comparative example.

[0111] (Implementation Method 2)

[0112] Figure 19A 1 is a perspective view showing the structure of one sector of the rotating electrical machine according to the second embodiment. Figure 19B yes Figure 19A A top view of the rotating motor. Figure 19C yes Figure 19A A side view of a rotating electrical machine, Figure 19D yes Figure 19A In the drawings of the rotating electrical machines of the second embodiment and the modified examples after the second embodiment, one sector is shown. However, when configuring the rotating electrical machine, a plurality of sectors may be combined and used as in the first embodiment.

[0113] Figures 19A to 19D Rotating motor and Figures 18A to 18D Compared with the rotating electric machine of the present invention, the following points are different. (1) The magnetic structure 15AB having through-holes 16 and 17a is provided instead of the magnetic structure 15AA having through-holes 16 and 17. That is, the through-hole 17a is formed instead of the through-hole 17 through which the terminal 14 passes. The following describes the differences.

[0114] exist Figure 19A and Figure 19B In the embodiment, through-holes 17a are formed so as to also penetrate the side surface of magnetic structure 15AB that is opposite to the surface of the adjacent sector in the circumferential direction. As a result, magnetic structure 15A provided at coil end portion 15a becomes discontinuous in the circumferential direction, reducing the effect of guiding circumferential leakage magnetic flux compared to embodiment 1, and slightly reducing the effect of reducing eddy current loss. However, embodiment 2 has the following effects.

[0115] According to the second embodiment configured as described above, by providing the magnetic structures 15AB and 15B at the coil end portions 15a and 15b, respectively, leakage magnetic flux and eddy current loss at the coil end portions 15a and 15b can be reduced compared to the comparative example.

[0116] (Implementation 3)

[0117] Figure 20A 1 is a perspective view showing the structure of one sector of the rotating electrical machine according to the third embodiment. Figure 20B yes Figure 20A A top view of a rotating electrical machine. Figures 20A and 20B Rotating motor and Figures 18A to 18D Compared with the rotating electric machine of the present invention, the following points are different. (1) The magnetic structure 15AC having through holes 16, 17 and a plurality of cooling through holes 18, 18a is included instead of the magnetic structure 15AA having through holes 16, 17. Figures 18A to 18D (2) A magnetic structure 15BC having a plurality of cooling through holes 18, 18a is provided instead of the magnetic structure 15B. The following describes the differences.

[0118] exist Figure 20A and Figure 20B In order to dissipate heat generated by coil 12 to the outside, cooling through-holes 18 and 18a are formed between through-holes 16 and 17 and the inner circumferential surfaces of magnetic structures 15AC and 15BC, extending vertically through the thickness of magnetic structures 15AC and 15BC (parallel to the axial direction of the rotating electrical machine). In one example of Embodiment 3, the diameter of cooling through-hole 18 is larger than the diameter of cooling through-hole 18a, but the present disclosure is not limited to this. Furthermore, in Embodiment 3, the formation of multiple cooling through-holes 18 and 18a reduces the effectiveness of guiding radial leakage magnetic flux compared to Embodiment 1.

[0119] According to the third embodiment configured as described above, the plurality of cooling through holes 18 and 18 a are formed in the magnetic structures 15AC and 15BC. This allows heat generated by the coil 12 to be released to the outside, and provides the same operational effects as those of the first embodiment.

[0120] (Implementation 4)

[0121] Figure 21A 1 is a perspective view showing the structure of one sector of the rotating electrical machine according to the fourth embodiment. Figure 21B yes Figure 21A A top view of a rotating electrical machine. Figures 21A and 21B Rotating motor and Figures 18A to 18D Compared with the rotating electrical machine case of the present invention, the following points are different. (1) The magnetic structure 15AD having through holes 16, 17 and a plurality of cooling through holes 19 is included instead of the magnetic structure 15AA having through holes 16, 17. Figures 18A to 18D(2) The magnetic structure 15B is replaced by a magnetic structure 15BD having a plurality of cooling through holes 19. The following describes the differences.

[0122] exist Figure 21A and Figure 21B In order to dissipate heat generated by coil 12 to the outside, cooling through-holes 19, 19 are formed between through-holes 16, 17 and the inner circumferential surfaces of magnetic structures 15AD, 15BD, extending vertically through magnetic structures 15AD, 15BD in the thickness direction (parallel to the axial direction of the rotating electrical machine). Furthermore, in Embodiment 4, the formation of multiple cooling through-holes 19, 19 reduces the effectiveness of guiding radial leakage magnetic flux compared to Embodiment 1.

[0123] According to the fourth embodiment configured as described above, the plurality of cooling through holes 19 and 19 are formed in the magnetic structures 15AD and 15BD. This allows heat generated by the coil 12 to be released to the outside, and provides the same operational effects as those of the first embodiment.

[0124] (Implementation 5)

[0125] Figure 22A 1 is a perspective view showing the structure of one sector of the rotating electrical machine according to the fifth embodiment. Figure 22B yes Figure 22A A three-dimensional diagram of a magnetic structure of a rotating electrical machine. Figure 22C yes Figure 22A A three-dimensional diagram of the magnetic structure of the rotating motor when it is turned upside down. Figure 22D yes Figure 22A A top view of a rotating electrical machine. Figures 22A to 22D Rotating motor and Figures 18A to 18D Compared to the rotating electric machine of the present invention, the following points are different. (1) Instead of the magnetic structure 15AA having through-holes 16 and 17, a magnetic structure 15AE having through-hole 16a and a plurality of cooling through-holes 40 is included. (2) Instead of the magnetic structure 15B, a magnetic structure 15BE having a plurality of cooling through-holes 40 is included. The following describes the differences.

[0126] exist Figures 22A to 22DIn order to dissipate heat generated by coil 12 to the outside, cooling through-holes 40, 40 are formed in a roughly semi-elliptical shape, for example, extending radially from the inner circumference of magnetic structures 15AE, 15BE to their outer circumferences, with the elliptical axis extending radially along the magnetic structures 15AE, 15BE. Here, magnetic structure 15AE is a comb-shaped structure comprising a curved base 41 on its inner circumference, multiple comb-shaped portions 42 extending radially from the curved base 41, and legs 43 joined at positions contacting the outer circumferences of each comb-shaped portion 42. Cooling through-holes 40 are formed between adjacent comb-shaped portions 42. Magnetic structure 15BE is constructed similarly to magnetic structure 15AE, except that it lacks through-hole 16a. Furthermore, in Embodiment 5, the formation of multiple cooling through-holes 40, 40 reduces the effectiveness of guiding radial leakage magnetic flux compared to Embodiment 1, allowing for larger openings on the outer circumference.

[0127] According to the fifth embodiment configured as described above, the plurality of cooling through holes 40 , 40 are formed in the magnetic structures 15AE, 15BE. This allows heat generated by the coil 12 to be released to the outside, and provides the same operational effects as those of the first embodiment.

[0128] (Implementation 6)

[0129] Figure 23A 1 is a perspective view showing the structure of one sector of the rotating electrical machine according to the sixth embodiment. Figure 23B yes Figure 23A A top view of a rotating electrical machine. Figures 23A and 23B Rotating motor and Figures 21A and 21B Compared with the rotating electric machine of the present invention, the following points are different. (1) The magnetic structure 15AF having through holes 16, 17 and a plurality of cooling through holes 19 is included instead of the magnetic structure 15AD having through holes 16, 17. Figures 21A and 21B (2) The magnetic structure 15BD is replaced with a magnetic structure 15BF having a plurality of cooling through holes 19. The following describes the differences.

[0130] exist Figure 23A and Figure 23B In the cooling through holes 19, 19 and Figure 21A and Figure 21B The magnetic structures 15AF and 15BF are formed in the same manner, but are Figure 4The flat base 215aa is composed of a flat base 215aa that is shorter in radial direction and thinner than the flat base 215a, and a leg portion 215c extending from the inner circumferential surface thereof in a direction parallel to the axial direction. A plurality of cooling through-holes 19 are formed in the flat base 215aa. Furthermore, in the sixth embodiment, the formation of the plurality of cooling through-holes 19 reduces the effectiveness of guiding radial leakage magnetic flux compared to the fourth embodiment. By reducing the thickness of the flat base 215aa of the magnetic structures 15AF and 15BF, the plurality of cooling through-holes 19 are dispersed in the circumferential direction, thereby reducing costs.

[0131] According to the sixth embodiment constructed as described above, a plurality of cooling through holes 19, 19 are formed in the magnetic structures 15AF, 15BF, thereby being able to dissipate heat generated by the coil 12 to the outside, and achieving the same effects as those of the fourth embodiment. Furthermore, compared to the fourth embodiment, the effect of guiding the leakage magnetic flux of the coil end portions 12a, 12b in the radial direction is reduced, and the effect of guiding it in the circumferential direction is also reduced, resulting in a reduced loss reduction effect.

[0132] (Implementation 7)

[0133] Figure 24A 1 is a perspective view showing the structure of one sector of the rotating electrical machine according to the seventh embodiment. Figure 24B yes Figure 24A View of a rotating electrical machine. Figure 24A and Figure 24B Rotating motor and Figure 23A and Figure 23B Compared with the rotating motor, the following points are different.

[0134] (1) The leg portion 215c is further provided with a plurality of cooling through-holes 19A having, for example, a cylindrical shape. Here, the cooling through-holes 19A are formed so as to penetrate the leg portion 215c in the radial direction.

[0135] The differences are described below.

[0136] According to the seventh embodiment, constructed as described above, the number of cooling through-holes 19 and 19A is increased compared to the fourth embodiment, the thickness of the flat base portion 215aa of the magnetic structures 15AG and 15BG is reduced compared to the first embodiment, and the cooling through-holes 19 and 19A are dispersed in the circumferential direction, thereby reducing costs. However, by providing the cooling through-holes 19A near the rotor 20, where the circumferential leakage magnetic field is relatively large, the effect of guiding the circumferential leakage magnetic field is reduced compared to the fourth embodiment, resulting in a lower loss reduction effect.

[0137] (Another variation)

[0138] In the above embodiments and modifications, the magnetic structures 15A, 15AA to 15AG, 15B, and 15BC to 15BG are provided at both ends of the coil end portions 15a and 15b, respectively. However, the present disclosure is not limited thereto, and the magnetic structures may be provided at at least one of the ends of the coil end portions 15a and 15b.

[0139] In the above-mentioned sixth and seventh embodiments, the cooling through-holes 19 and 19A are formed, but the present disclosure is not limited thereto, and at least one of the cooling through-holes 19 and 19A may not be formed.

[0140] Example

[0141] Table 1 below shows the results of simulation calculations of eddy current losses for the rotating electrical machines of the comparative example and the embodiment described above.

[0142] [Table 1]

[0143] surface

[0144]

[0145] As can be seen from Table 1, among these four examples, the eddy current loss of Embodiment 1 is the smallest, and the eddy current loss of the comparative example is the largest. In other words, it can be seen that the loss is reduced by discontinuing the conduction of the circumferential leakage magnetic flux.

[0146] Industrial applicability

[0147] As described in detail above, according to one form of the rotating motor disclosed herein, the eddy current loss in the coil can be reduced by suppressing the increase in the induced electromotive force (electromotive force of eddy current) caused by the leakage magnetic flux at the end of the coil and the increase in the leakage magnetic flux at the end of the coil due to miniaturization, thereby significantly reducing the loss of the coil.

[0148] Description of Reference Numerals

[0149] 1. Rotating electric machine; 10. Stator; 10A, 10C, a sector of the rotor; 11. Magnetic core; 12. Coil; 12a, 12b, coil end portions; 13, 14, terminals; 15A, 15AA to 15AG, 15B, 15BC to 15BG, magnetic structure; 16, 16a, 17, 17a, 17b, through-holes; 18, 18a, 19, 19A, cooling through-holes; 20. Rotor; 21. Rotating shaft; 22. Magnetic core; 23. Permanent magnet; 41. Curved base; 42. Comb-shaped portion; 43. Leg; 215a, 215aa, flat base; 215b, 215c, legs.

Claims

1. A rotating electrical machine, wherein: The rotating electrical machine includes: a stator having a coil and a first magnetic core; and a rotor having a permanent magnet and a second magnetic core. This rotating electrical machine includes a magnetic structure provided at at least one of two coil end portions serving as both ends of the coil and guiding magnetic flux from the second magnetic core toward the first magnetic core.

2. The rotating electrical machine according to claim 1, wherein The magnetic structure guides the magnetic flux from the second magnetic core toward the first magnetic core in the radial direction of the rotating electric machine, and guides the magnetic flux from the second magnetic core toward the first magnetic core in the circumferential direction of the rotating electric machine.

3. The rotating electrical machine according to claim 1, wherein The magnetic structure is provided so that the magnetic flux does not substantially interlink with the coil.

4. The rotating electrical machine according to claim 1, wherein The magnetic structure includes a plurality of first cooling through holes that penetrate the magnetic structure in a direction parallel to the axial direction of the rotating electrical machine.

5. The rotating electrical machine according to claim 4, wherein The plurality of first cooling through holes are formed in the magnetic structure so as to extend from positions near the inner peripheral surface of the stator toward the outer peripheral surface of the stator.

6. The rotating electrical machine according to claim 4 or 5, wherein: The magnetic structure includes a plurality of second cooling through holes that penetrate the magnetic structure in a direction parallel to a radial direction of the rotating electrical machine.

7. The rotating electric machine according to claim 1, wherein The magnetic structure includes a flat base portion extending from the inner peripheral surface to the outer peripheral surface of the stator, and a pair of legs extending from both radial ends of the flat base portion in the axial direction of the rotating electrical machine.

8. The rotating electrical machine according to claim 7, wherein The magnetic structure includes a plurality of first cooling through holes that penetrate the flat base portion in a direction parallel to the axial direction of the rotating electrical machine.

9. The rotating electric machine according to claim 1, wherein The magnetic structure includes a flat base portion extending from the inner peripheral surface to the outer peripheral surface of the stator, and a leg portion extending in the axial direction of the rotating electric machine from one end of the flat base portion on the inner peripheral surface side in the radial direction.

10. The rotating electrical machine according to claim 9, wherein The magnetic structure includes a plurality of first cooling through holes that penetrate the flat base portion in a direction parallel to the axial direction of the rotating electrical machine.

11. The rotating electrical machine according to claim 10, wherein The magnetic structure includes a plurality of second cooling through holes that penetrate the leg portion in a direction parallel to a radial direction of the rotating electrical machine.

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