WO2020021844A1 - Rotating electric machine stator - Google Patents

Abstract

This rotating electric machine stator is a stator (50) disposed coaxially with a rotatably supported rotor (40) and is provided with an annular stator core (52) and stator windings (51) having a plurality of phases, which are covered with an insulating film (82b). The stator windings have: magnet opposed portions (83) facing magnet portions (42) of the rotor in the radial direction of the rotating shaft of the rotating electric machine; and turn portions (84) that connect the magnet opposed portions having the same phase to each other outside the magnet opposed portions in the axial direction of the rotating shaft. At least one of the turn portions provided on both sides in the axial direction serves as heat-dissipation accelerating turn portions (841). The heat-dissipation accelerating turn portions are provided such that the heat-dissipation accelerating turn portions having different phases are partially overlapped with each other in the axial direction, and project in the radial direction with respect to the magnet opposed portions. The heat-dissipation accelerating turn portions having different phases, which are overlapped in the axial direction, are provided with: the most inner layer turn portion (841U) provided at the position nearest to the stator core in the axial direction; and outer layer turn portions (841V, 841W) provided at positions further from the stator core than the most inner layer turn portion in the axial direction. The projection amount of the most inner layer turn portion in the radial direction is different from the projection amounts of the outer layer turn portions in the radial direction.

Description

Rotating electric machine stator Cross-reference of related applications

This application is based on Japanese Patent Application No. 2018-139470 filed on July 25, 2018, the contents of which are incorporated herein by reference.

The present disclosure relates to a stator of a rotating electric machine.

Patent Literature 1 discloses a technology in which a two-phase winding is formed by combining a long and short coil end in a stator winding of a rotating electric machine in order to prevent a reduction in efficiency and a reduction in generated torque. Has been disclosed.

JP-A-61-224841

(4) In the configuration of the related art, heat generated by energization of the coil is likely to be trapped in the overlapping portion between the coils, and the temperature of the coil is likely to rise. If the temperature of the coil rises abnormally, there is a concern that the rotating electrical machine will not function properly due to thermal degradation of the coating of the conductive wire forming the coil and a decrease in the insulation of the coil. In view of the above, or other aspects not mentioned, there is a need for further improvements in the rotating electrical machine stator.

The present disclosure aims to provide a stator for a rotating electric machine having high heat dissipation performance.

The stator of the rotating electric machine according to the first aspect of the present disclosure includes an annular stator core, and a plurality of phases of stator windings covered with an insulating coating, and is coaxial with the rotatably supported rotor. It is a stator arranged in. The stator winding is a turn connecting the magnet facing portion radially facing the magnet portion of the rotor and the magnet facing portion of the same phase outside the magnet facing portion in the axial direction of the rotating shaft. And a part. At least one of the turn portions provided on both sides in the axial direction is a heat dissipation promoting turn portion. The heat-dissipating turn parts are provided such that the heat-dissipating turn parts of different phases partially overlap each other in the axial direction, and protrude radially with respect to the magnet facing part. Of the different phases of the heat dissipation promoting turns overlapping in the axial direction, the innermost turn part provided at the position closest to the stator core in the axial direction, and a position farther from the stator core than the innermost turn part in the axial direction. And an outer layer turn portion provided. The radially projecting amount of the innermost turn portion is different from the radially projecting amount of the outer layer turn portion.

According to the stator of the disclosed rotating electrical machine, in the innermost turn portion and the outer turn portion forming the heat radiation promotion turn portion, the radially projecting amount of the innermost turn portion is the radially projecting amount of the outer layer turn portion. The amount of protrusion is different from the amount. For this reason, compared with the case where the radially projecting amount of the innermost turn portion and the radially projecting amount of the outer layer turn portion are equal, the portion where the innermost turn portion and the outer layer turn portion do not overlap in the axial direction is considered. It is possible to secure a large amount and promote heat radiation into the air. Therefore, as compared with the case where the innermost turn portion and the outermost turn portion overlap with each other, a large contact area with air can be easily secured, and the heat generated in the innermost turn portion is less likely to be trapped. Therefore, it is possible to provide a stator of a rotating electric machine having high heat dissipation performance.

The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description with reference to the accompanying drawings. The drawing is
FIG. FIG. 4 is a longitudinal sectional view of the rotating electric machine. FIG. 3 is a sectional view taken along line III-III of FIG. 2. Sectional drawing which expands and shows a part of FIG. FIG. FIG. 3 is an exploded view of the inverter unit. FIG. 4 is a torque diagram showing a relationship between an ampere-turn of a stator winding and a torque density. FIG. 4 is a cross-sectional view of the rotor and the stator. The figure which expands and shows a part of FIG. FIG. The longitudinal section of a stator. The perspective view of a stator winding. FIG. 2 is a perspective view showing a configuration of a conductive wire. The schematic diagram which shows the structure of a strand. The figure which shows the form of each lead in the n-th layer. FIG. 6 is a side view showing the respective conductors of the nth layer and the (n + 1) th layer. The figure which shows the relationship between an electric angle and magnetic flux density about the magnet of embodiment. The figure which shows the relationship between an electric angle and a magnetic flux density about the magnet of a comparative example. The electric circuit diagram of the control system of a rotating electric machine. FIG. 4 is a functional block diagram showing current feedback control processing by the control device. FIG. 4 is a functional block diagram illustrating a torque feedback control process performed by the control device. FIG. 6 is a cross-sectional view of a rotor and a stator according to a second embodiment. The figure which expands and shows a part of FIG. The figure which shows the flow of the magnetic flux in a magnet part concretely. Sectional drawing of the stator in another example. Sectional drawing of the stator in another example. Sectional drawing of the stator in another example. Sectional drawing of the stator in another example. The side view which shows each conductor of the nth layer and the n + 1th layer in another example. Sectional drawing of the stator in another example. FIG. 2 is a longitudinal sectional view of the rotating electric machine according to the first embodiment. FIG. 2 is a perspective view of a stator according to the first embodiment. The figure which expands and shows a part of FIG. FIG. 3 is a top view of the stator according to the first embodiment. The figure which expands and shows a part of FIG.

複数 A plurality of embodiments will be described with reference to the drawings. In embodiments, functionally and / or structurally corresponding parts and / or associated parts may be provided with the same reference signs or reference signs that differ by more than a hundred places. For corresponding parts and / or associated parts, the description of the other embodiments can be referred to.

(1st Embodiment)
Hereinafter, the rotating electric machine 10 as a basic form to which the stator 50 of the rotating electric machine 10 according to the present embodiment can be applied will be described with reference to FIGS. 1 to 21.

The rotating electric machine 10 according to the present embodiment is a synchronous polyphase AC motor and has an outer rotor structure (eternal rotation structure). The outline of the rotating electric machine 10 is shown in FIGS. 1 is a vertical cross-sectional perspective view of the rotary electric machine 10, FIG. 2 is a vertical cross-sectional view of the rotary electric machine 10 in a direction along a rotation axis 11, and FIG. 3 is a cross-sectional view (cross-sectional view taken along line III-III of FIG. 2) of the rotating electric machine 10, FIG. 4 is a cross-sectional view showing a part of FIG. 3 in an enlarged manner, and FIG. It is. In FIG. 3, hatching indicating a cut surface is omitted except for the rotation shaft 11 for convenience of illustration. In the following description, the direction in which the rotating shaft 11 extends is defined as the axial direction, the direction radially extending from the center of the rotating shaft 11 is defined as the radial direction, and the direction extending circumferentially around the rotating shaft 11 is defined as the circumferential direction.

The rotating electric machine 10 roughly includes a bearing unit 20, a housing 30, a rotor 40, a stator 50, and an inverter unit 60. Each of these members is arranged coaxially with the rotating shaft 11 and assembled in a predetermined order in the axial direction to form the rotating electric machine 10.

The bearing portion 20 has two bearings 21 and 22 that are arranged apart from each other in the axial direction, and a holding member 23 that holds the bearings 21 and 22. The bearings 21 and 22 are, for example, radial ball bearings, each of which has an outer ring 25, an inner ring 26, and a plurality of balls 27 arranged between the outer ring 25 and the inner ring 26. The holding member 23 has a cylindrical shape, and bearings 21 and 22 are attached to the inside in the radial direction. The rotating shaft 11 and the rotor 40 are rotatably supported inside the bearings 21 and 22 in the radial direction.

The housing 30 has a cylindrical peripheral wall portion 31 and an end surface portion 32 provided at one end of both ends in the axial direction of the peripheral wall portion 31. An opening 33 is formed on the opposite side of the end face portion 32 of both ends in the axial direction of the peripheral wall portion 31, and the housing 30 has a configuration in which the opposite side of the end face portion 32 is completely opened by the opening 33. . A circular hole 34 is formed in the center of the end face portion 32, and the bearing portion 20 is fixed by a fixing tool such as a screw or a rivet in a state of being inserted through the hole 34. The rotor 40 and the stator 50 are accommodated in the housing 30, that is, in an internal space defined by the peripheral wall portion 31 and the end surface portion 32. In the present embodiment, the rotating electric machine 10 is of an outer rotor type, and a stator 50 is disposed inside a housing 30 in a radial direction of a cylindrical rotor 40. The rotor 40 is cantilevered by the rotating shaft 11 on the end face 32 side in the axial direction.

The rotor 40 has a rotor main body 41 formed in a hollow cylindrical shape, and an annular magnet portion 42 provided radially inside the rotor main body 41. The rotor main body 41 has a substantially cup shape and has a function as a magnet holding member. The rotor main body 41 has a cylindrical magnet holding portion 43, a fixed portion 44 which is also cylindrical and has a smaller diameter than the magnet holding portion 43, and an intermediate portion serving as a portion connecting the magnet holding portion 43 and the fixed portion 44. And a part 45. The magnet part 42 is attached to the inner peripheral surface of the magnet holding part 43.

The rotating shaft 11 is inserted through the through hole 44 a of the fixing portion 44, and the fixing portion 44 is fixed to the rotating shaft 11 in the inserted state. That is, the rotor main body 41 is fixed to the rotating shaft 11 by the fixing portion 44. The fixing portion 44 may be fixed to the rotating shaft 11 by spline connection or key connection using irregularities, welding, caulking, or the like. Thereby, the rotor 40 rotates integrally with the rotating shaft 11.

軸 受 Bearings 21 and 22 of the bearing portion 20 are mounted radially outside the fixing portion 44. As described above, since the bearing 20 is fixed to the end face 32 of the housing 30, the rotating shaft 11 and the rotor 40 are rotatably supported by the housing 30. Thereby, the rotor 40 is rotatable in the housing 30.

固定 The rotor 40 is provided with the fixing portion 44 on only one of the two axial sides, whereby the rotor 40 is cantilevered on the rotating shaft 11. Here, the fixed portion 44 of the rotor 40 is rotatably supported at two different positions in the axial direction by the bearings 21 and 22 of the bearing portion 20. That is, the rotor 40 is rotatably supported by the two bearings 21 and 22 in the axial direction on one of the two axial ends of the rotor main body 41. Therefore, even when the rotor 40 has a structure in which the rotor 40 is cantilevered by the rotating shaft 11, stable rotation of the rotor 40 is realized. In this case, the rotor 40 is supported by the bearings 21 and 22 at a position shifted to one side with respect to the axial center position of the rotor 40.

Further, in the bearing portion 20, the bearing 22 near the center of the rotor 40 (the lower side in the figure) and the bearing 21 on the opposite side (the upper side in the figure) have a gap between the outer ring 25 and the inner ring 26 and the ball 27. The dimensions are different, for example, the bearing 22 near the center of the rotor 40 has a larger gap size than the bearing 21 on the opposite side. In this case, on the side near the center of the rotor 40, even if vibration of the rotor 40 or vibration due to imbalance due to component tolerance acts on the bearing portion 20, the influence of the vibration and vibration is favorably absorbed. You. Specifically, the play size (gap size) is increased by the preload in the bearing 22 near the center of the rotor 40 (the lower side in the figure), so that the vibration generated in the cantilever structure is absorbed by the play portion. You. The preload may be a fixed position preload, or may be applied by inserting a preload spring, a wave washer, or the like into an axially outer step (upper side in the figure) of the bearing 22.

中間 The intermediate portion 45 is configured to have a step in the axial direction between the center in the radial direction and the outside thereof. In this case, in the intermediate portion 45, the radial inner end portion and the radial outer end portion have different axial positions, so that the magnet holding portion 43 and the fixing portion 44 partially overlap in the axial direction. are doing. In other words, the magnet holding portion 43 protrudes outward in the axial direction from the base end of the fixing portion 44 (the lower end on the lower side in the figure). In this configuration, the rotor 40 can be supported on the rotating shaft 11 at a position near the center of gravity of the rotor 40 as compared with the case where the intermediate portion 45 is provided in a flat shape without a step. Forty stable operations can be realized.

According to the configuration of the intermediate portion 45 described above, the rotor housing 40 has a bearing housing recess 46 that partially surrounds the bearing portion 20 at a position that surrounds the fixed portion 44 in the radial direction and is inward of the intermediate portion 45. Is formed in an annular shape, and encloses the bearing accommodating recess 46 in the radial direction and is located outside of the intermediate portion 45, and accommodates a coil end portion 54 of a stator winding 51 of a stator 50 described later. A recess 47 is formed. These accommodation recesses 46 and 47 are arranged so as to be adjacent to each other inside and outside in the radial direction. That is, a part of the bearing portion 20 and the coil end portion 54 of the stator winding 51 are arranged so as to overlap inward and outward in the radial direction. Thus, the axial length of the rotating electric machine 10 can be reduced.

(4) The coil end portion 54 is bent inward or outward in the radial direction, so that the axial dimension of the coil end portion 54 can be reduced, and the axial length of the stator can be shortened. The bending direction of the coil end portion 54 should preferably take into account the assembly with the rotor 40. Assuming that the stator 50 is assembled radially inward of the rotor 40, it is preferable that the coil end portion 54 be bent radially inward on the insertion front end side with respect to the rotor 40. The bending direction on the opposite side may be arbitrary, but the outer diameter side having a sufficient space is preferable in manufacturing. The coil end portion 54 when bent will be described later in detail with reference to FIGS.

(4) The magnet portion 42 is formed of a plurality of magnets arranged radially inside the magnet holding portion 43 so that the magnetic poles alternate alternately along the circumferential direction. However, the details of the magnet section 42 will be described later.

The stator 50 is provided radially inside the rotor 40. The stator 50 has a stator winding 51 wound in a substantially cylindrical shape, and a stator core 52 disposed radially inward of the stator winding 51. It is arranged so as to face the annular magnet portion 42 with the gap interposed. The stator winding 51 includes a plurality of phase windings. Each of the phase windings is configured by connecting a plurality of conductors arranged in a circumferential direction at a predetermined pitch. In the present embodiment, three-phase windings of U-phase, V-phase, and W-phase, and three-phase windings of X-phase, Y-phase, and Z-phase are used. , The stator winding 51 is configured as a six-phase winding.

The stator core 52 is formed in an annular shape from a laminated steel plate made of a soft magnetic material, and is assembled radially inside the stator winding 51.

The stator winding 51 is a portion that overlaps the stator core 52 in the axial direction, and is a coil side portion 53 that is radially outside the stator core 52, and one end of the stator core 52 in the axial direction and the other. Coil end portions 54 and 55 projecting to the end sides are provided. The coil side portion 53 faces the stator core 52 and the magnet portion 42 of the rotor 40 in the radial direction. In a state where the stator 50 is arranged inside the rotor 40, the coil end portion 54 on the side of the bearing portion 20 (upper side in the drawing) of the coil end portions 54 and 55 on both sides in the axial direction is connected to the rotor 40. It is housed in a coil housing recess 47 formed by the rotor main body 41. However, details of the stator 50 will be described later.

The inverter unit 60 has a unit base 61 fixed to the housing 30 by fasteners such as bolts, and an electric component 62 assembled to the unit base 61. The unit base 61 includes an end plate 63 fixed to an end of the housing 30 on the opening 33 side, and a casing 64 provided integrally with the end plate 63 and extending in the axial direction. I have. The end plate 63 has a circular opening 65 at the center thereof, and a casing 64 is formed so as to stand up from the peripheral edge of the opening 65.

固定 The stator 50 is mounted on the outer peripheral surface of the casing 64. That is, the outer diameter of the casing portion 64 is the same as the inner diameter of the stator core 52 or slightly smaller than the inner diameter of the stator core 52. By attaching the stator core 52 to the outside of the casing 64, the stator 50 and the unit base 61 are integrated. Further, when the unit base 61 is fixed to the housing 30, the stator 50 is integrated with the housing 30 in a state where the stator core 52 is attached to the casing portion 64.

Further, the radially inner side of the casing portion 64 is a housing space for housing the electric component 62, and the electric component 62 is arranged in the housing space so as to surround the rotating shaft 11. The casing part 64 has a role as an accommodation space forming part. The electric component 62 includes a semiconductor module 66 constituting an inverter circuit, a control board 67, and a capacitor module 68.

Here, the configuration of the inverter unit 60 will be further described with reference to FIG. 6 which is an exploded view of the inverter unit 60 in addition to FIGS.

In the unit base 61, the casing portion 64 includes a cylindrical portion 71 and an end surface portion 72 provided at one end (an end on the bearing portion 20 side) of both ends in the axial direction of the cylindrical portion 71. Have. The opposite side of the end face portion 72 of the both ends in the axial direction of the cylindrical portion 71 is completely opened through the opening 65 of the end plate portion 63. A circular hole 73 is formed in the center of the end face portion 72, and the rotary shaft 11 can be inserted through the hole 73.

The cylindrical portion 71 of the casing portion 64 serves as a partition portion that partitions between the rotor 40 and the stator 50 disposed radially outward and the electric component 62 disposed radially inward thereof. The rotor 40, the stator 50, and the electric component 62 are arranged radially inward and outward with the tubular portion 71 interposed therebetween.

The electric component 62 is an electric component forming an inverter circuit, and has a powering function of rotating the rotor 40 by applying a current to each phase winding of the stator winding 51 in a predetermined order; And a power generation function of inputting a three-phase AC current flowing through the stator winding 51 with the rotation of the motor and outputting the generated power to the outside. The electric component 62 may have only one of the powering function and the power generation function. The power generation function is, for example, a regenerative function that outputs to the outside as regenerative power when the rotating electric machine 10 is used as a vehicle power source.

As a specific configuration of the electric component 62, a hollow cylindrical capacitor module 68 is provided around the rotation shaft 11, and a plurality of semiconductor modules 66 are provided on the outer peripheral surface of the capacitor module 68 in the circumferential direction. Are arranged side by side. The capacitor module 68 includes a plurality of smoothing capacitors 68a connected in parallel with each other. Specifically, the capacitor 68a is a laminated film capacitor in which a plurality of film capacitors are laminated, and has a trapezoidal cross section. The capacitor module 68 is configured by arranging twelve capacitors 68a in a ring.

In the manufacturing process of the capacitor 68a, for example, a long film having a predetermined width formed by laminating a plurality of films is used, the film width direction is set to a trapezoidal height direction, and the upper and lower bases of the trapezoid alternate. The long film is cut into an equal-leg trapezoidal shape so that the capacitor element is formed. Then, by attaching electrodes and the like to the capacitor element, the capacitor 68a is manufactured.

The semiconductor module 66 has a semiconductor switching element such as a MOSFET or an IGBT, and is formed in a substantially plate shape. In the present embodiment, the rotary electric machine 10 includes two sets of three-phase windings, and an inverter circuit is provided for each of the three-phase windings. Is provided.

The semiconductor module 66 is disposed between the cylindrical portion 71 of the casing 64 and the capacitor module 68. The outer peripheral surface of the semiconductor module 66 contacts the inner peripheral surface of the cylindrical portion 71, and the inner peripheral surface of the semiconductor module 66 contacts the outer peripheral surface of the capacitor module 68. In this case, heat generated in the semiconductor module 66 is transmitted to the end plate 63 via the casing 64 and is released from the end plate 63.

The semiconductor module 66 preferably has a spacer 69 between the semiconductor module 66 and the cylindrical portion 71 in the outer peripheral surface side, that is, in the radial direction. In this case, in the capacitor module 68, the cross-sectional shape of the cross section orthogonal to the axial direction is a regular dodecagon, while the cross-sectional shape of the inner peripheral surface of the cylindrical portion 71 is circular. Has a flat surface and the outer peripheral surface is a curved surface. The spacer 69 may be provided integrally so as to be annularly continuous outside the semiconductor module 66 in the radial direction. Note that the cross-sectional shape of the inner peripheral surface of the cylindrical portion 71 can be the same dodecagon as that of the capacitor module 68. In this case, both the inner peripheral surface and the outer peripheral surface of the spacer 69 are preferably flat surfaces.

Further, in the present embodiment, a cooling water passage 74 for flowing cooling water is formed in the cylindrical portion 71 of the casing 64, and heat generated in the semiconductor module 66 is transferred to the cooling water flowing through the cooling water passage 74. Also released. That is, the casing 64 has a water cooling mechanism. As shown in FIGS. 3 and 4, the cooling water passage 74 is formed in an annular shape so as to surround the electric component 62 (the semiconductor module 66 and the capacitor module 68). The semiconductor module 66 is arranged along the inner peripheral surface of the cylindrical portion 71, and a cooling water passage 74 is provided at a position overlapping the semiconductor module 66 inward and outward in the radial direction.

Since the stator 50 is disposed outside the tubular portion 71 and the electric component 62 is disposed inside, the heat of the stator 50 is transmitted to the tubular portion 71 from the outside, The heat of the semiconductor module 66 is transmitted from the inside. In this case, the stator 50 and the semiconductor module 66 can be cooled at the same time, and the heat of the heat generating member in the rotating electric machine 10 can be efficiently released.

{Circle around (2)} The electric component 62 includes an insulating sheet 75 provided on one end face of the capacitor module 68 and a wiring module 76 provided on the other end face in the axial direction. In this case, one end face (the end face on the bearing portion 20 side) of both end faces in the axial direction of the capacitor module 68 is opposed to the end face portion 72 of the casing portion 64, and the end face portion 72 is sandwiched by the insulating sheet 75. Has been superimposed. A wiring module 76 is mounted on the other end surface (the end surface on the opening 65 side).

The wiring module 76 has a main body portion 76a made of a synthetic resin and having a circular plate shape, and a plurality of busbars 76b and 76c embedded therein. The busbars 76b and 76c allow the semiconductor module 66 and the capacitor to be mounted. An electrical connection is made with the module 68. Specifically, the semiconductor module 66 has a connection pin 66a extending from the axial end face, and the connection pin 66a is connected to the bus bar 76b on the radial outside of the main body portion 76a. The bus bar 76c extends on the outer side of the main body 76a in the radial direction on the side opposite to the capacitor module 68, and is connected to the wiring member 79 at its tip (see FIG. 2).

According to the configuration in which the insulating sheet 75 and the wiring module 76 are provided on both sides in the axial direction of the capacitor module 68 as described above, the heat radiation paths of the capacitor module 68 are provided from both end surfaces in the axial direction of the capacitor module 68 to the end surface 72 and A path leading to the cylindrical portion 71 is formed. Thereby, heat can be radiated from the end face of the capacitor module 68 other than the outer peripheral face where the semiconductor module 66 is provided. That is, not only the heat radiation in the radial direction but also the heat radiation in the axial direction are possible.

Further, since the capacitor module 68 has a hollow cylindrical shape and the rotating shaft 11 is disposed on the inner peripheral portion thereof with a predetermined gap interposed therebetween, the heat of the capacitor module 68 can be released from the hollow portion. ing. In this case, the flow of air is generated by the rotation of the rotating shaft 11, so that the cooling effect is enhanced.

円 A disc-shaped control board 67 is attached to the wiring module 76. The control board 67 has a printed circuit board (PCB) on which a predetermined wiring pattern is formed, and a control device 77 including various ICs and a microcomputer is mounted on the board. The control board 67 is fixed to the wiring module 76 by a fixture such as a screw. The control board 67 has an insertion hole 67a at the center thereof, through which the rotating shaft 11 is inserted.

A control board 67 is provided on the opposite side of the capacitor module 68 from both sides in the axial direction of the wiring module 76, and the bus bar 76c of the wiring module 76 extends from one side of the control board 67 to the other side. I have. In such a configuration, the control board 67 may be provided with a notch for avoiding interference with the bus bar 76c. For example, a part of the outer edge of the circular control board 67 may be cut away.

As described above, according to the configuration in which the electric component 62 is accommodated in the space surrounded by the casing portion 64 and the housing 30, the rotor 40, and the stator 50 are provided in layers outside the space, the inverter circuit is used. The resulting electromagnetic noise is suitably shielded. That is, in the inverter circuit, switching control in each semiconductor module 66 is performed using PWM control based on a predetermined carrier frequency, and electromagnetic noise may be generated by the switching control. It can be shielded suitably by the housing 30, the rotor 40, the stator 50, and the like outside in the radial direction of 62.

In the vicinity of the end plate 63 in the cylindrical portion 71, a through hole 78 is formed through which a wiring member 79 (see FIG. 2) for electrically connecting the outer stator 50 and the inner electric component 62 is inserted. ing. As shown in FIG. 2, the wiring member 79 is connected to the end of the stator winding 51 and the bus bar 76c of the wiring module 76 by crimping, welding, or the like. The wiring member 79 is, for example, a bus bar, and its joint surface is desirably flattened. The through holes 78 may be provided at one or a plurality of positions. In the present embodiment, the through holes 78 are provided at two positions. In the configuration in which the through holes 78 are provided at two locations, the winding terminals extending from the two sets of three-phase windings can be easily connected by the wiring members 79, respectively, which is suitable for performing multiphase connection. It has become.

As described above, in the housing 30, the rotor 40 and the stator 50 are provided in this order from the outside in the radial direction as shown in FIG. 4, and the inverter unit 60 is provided inside the stator 50 in the radial direction. Here, assuming that the radius of the inner peripheral surface of the housing 30 is d, the rotor 40 and the stator 50 are arranged radially outward from a distance of d × 0.705 from the center of rotation. In this case, of the rotor 40 and the stator 50, a region radially inward from the inner peripheral surface of the stator 50 on the radial inner side (that is, the inner peripheral surface of the stator core 52) is defined as a first region X1, Assuming that a region between the inner peripheral surface of the stator 50 and the housing 30 is the second region X2, the cross-sectional area of the first region X1 is larger than the cross-sectional area of the second region X2. I have. Further, when viewed in a range where the magnet portion 42 of the rotor 40 and the stator winding 51 overlap in the axial direction, the volume of the first region X1 is larger than the volume of the second region X2.

Assuming that the rotor 40 and the stator 50 are magnetic circuit components, a first region X1 radially inward from the inner peripheral surface of the magnetic circuit component in the housing 30 is radially inward of the magnetic circuit component. The volume is larger than the second area X2 between the surface and the housing 30.

Next, the configurations of the rotor 40 and the stator 50 will be described in more detail.

Generally, as a configuration of a stator in a rotating electric machine, there is known a configuration in which a plurality of slots are provided in a circumferential direction on a stator core made of laminated steel sheets and forming an annular shape, and a stator winding is wound in the slots. I have. Specifically, the stator core has a plurality of teeth extending in the radial direction at predetermined intervals from the yoke portion, and a slot is formed between teeth adjacent in the circumferential direction. A plurality of layers of conductors are accommodated in the slot, for example, in the radial direction, and the conductors constitute a stator winding.

However, in the above-described stator structure, when the stator winding is energized, magnetic saturation occurs in the teeth of the stator core as the magnetomotive force of the stator winding increases, and as a result, the rotating electric machine It is possible that the torque density is limited. That is, in the stator core, it is considered that the magnetic flux is generated by energizing the stator windings and concentrates on the teeth, thereby causing magnetic saturation.

Generally, as a configuration of an IPM rotor in a rotating electric machine, a configuration in which a permanent magnet is arranged on a d-axis and a rotor core is arranged on a q-axis is known. In such a case, when the stator winding near the d-axis is excited, the excitation magnetic flux flows from the stator to the q-axis of the rotor according to Fleming's law. It is considered that this causes a wide range of magnetic saturation in the q-axis core portion of the rotor.

FIG. 7 is a torque diagram showing the relationship between the ampere turn [AT] indicating the magnetomotive force of the stator winding and the torque density [Nm / L]. The dashed line indicates the characteristic in a general IPM rotor type rotating electric machine. As shown in FIG. 7, in a general rotating electric machine, by increasing the magnetomotive force in the stator, magnetic saturation occurs at two places, ie, the teeth portion between the slots and the q-axis core portion. The increase in torque is limited. As described above, in the general rotating electric machine, the ampere-turn design value is limited by X1.

Therefore, in the present embodiment, the following configuration is added to the rotating electric machine 10 in order to eliminate the torque limitation caused by the magnetic saturation. That is, as a first contrivance, a slotless structure is employed in the stator 50 in order to eliminate magnetic saturation caused by teeth of the stator core in the stator, and in order to eliminate magnetic saturation occurring in the q-axis core portion of the IPM rotor. , SPM rotor. According to the first device, the above two portions where magnetic saturation occurs can be eliminated, but it is conceivable that the torque in the low current region decreases (see the dashed line in FIG. 7). Therefore, as a second contrivance, a pole anisotropic structure in which the magnet magnetic path is lengthened to increase the magnetic force in the magnet section 42 of the rotor 40 is adopted in order to recover the torque reduction by increasing the magnetic flux of the SPM rotor. ing.

As a third device, a flat conductor structure in which the radial thickness of the conductor is reduced in the coil side portion 53 of the stator winding 51 is employed to reduce the torque reduction. Here, it is conceivable that a larger eddy current is generated in the opposed stator winding 51 due to the above-described pole anisotropic structure in which the magnetic force is increased. However, according to the third device, the generation of radial eddy currents in the stator windings 51 can be suppressed because the flat conductive wire structure is thin in the radial direction. As described above, according to each of the first to third configurations, as shown by the solid line in FIG. 7, while a magnet having a high magnetic force is employed to greatly improve the torque characteristics, the magnet having a high magnetic force is used. Concerns about possible large eddy current generation can also be improved.

Further, as a fourth contrivance, a magnet part having a magnetic flux density distribution close to a sine wave using a pole anisotropic structure is adopted. According to this, the sine wave matching ratio can be increased by pulse control or the like to be described later to increase the torque, and the eddy current loss can be further suppressed due to a gradual change in magnetic flux compared to the radial magnet. .

(5) As a fifth contrivance, the stator winding 51 has a strand conductor structure in which a plurality of strands are gathered and twisted. According to this, while the fundamental wave component is collected, a large current can flow, and the generation of eddy current due to the circumferential direction generated by the conductor that spreads in the circumferential direction with the flat wire structure reduces the cross-sectional area of each element wire. Since the thickness is reduced, the thickness can be more effectively suppressed than when the thickness is reduced in the radial direction by the third device. And, since the plurality of strands are twisted, the eddy current with respect to the magnetic flux generated by the rule of the right-hand screw with respect to the current flowing direction can be offset with respect to the magnetomotive force from the conductor.

As described above, when the fourth device and the fifth device are further added, the torque is increased while the eddy current loss caused by the high magnetic force is suppressed while employing the magnet having the high magnetic force as the second device. Can be planned.

ス ロ ッ ト Hereinafter, the slotless structure of the stator 50, the flat conductor structure of the stator winding 51, and the pole anisotropic structure of the magnet portion 42 will be individually described. First, the slotless structure of the stator 50 and the flat conductor structure of the stator winding 51 will be described. FIG. 8 is a cross-sectional view of the rotor 40 and the stator 50, and FIG. 9 is an enlarged view of a part of the rotor 40 and the stator 50 shown in FIG. FIG. 10 is a cross-sectional view showing a horizontal cross section of the stator 50, and FIG. 11 is a cross-sectional view showing a vertical cross section of the stator 50. FIG. 12 is a perspective view of the stator winding 51. 8 and 9, the magnetization directions of the magnets in the magnet section 42 are indicated by arrows.

As shown in FIGS. 8 to 11, the stator core 52 is formed by stacking a plurality of electromagnetic steel sheets in the axial direction and has a cylindrical shape having a predetermined thickness in the radial direction. The child winding 51 is to be assembled. The outer peripheral surface of the stator core 52 is a conductive wire installation part. The outer peripheral surface of the stator core 52 has a curved surface without irregularities, and a plurality of conductive wire groups 81 are arranged on the outer peripheral surface in a circumferential direction. The stator core 52 functions as a back yoke which is a part of a magnetic circuit for rotating the rotor 40. In this case, the configuration is such that no teeth (that is, iron core) made of a soft magnetic material are provided between the conductor groups 81 that are adjacent in the circumferential direction (that is, a slotless structure). In the present embodiment, the structure is such that the resin material of the sealing portion 57 enters the gaps 56 between the respective conductive wire groups 81. That is, speaking of the state before the sealing of the sealing portion 57, the conductor groups 81 are arranged radially outside the stator core 52 at predetermined intervals in the circumferential direction with the gap 56, which is a region between the conductors, interposed therebetween. As a result, a stator 50 having a slotless structure is constructed. The sealing portion 57 provides an inter-wire member.

Note that the configuration in which the teeth are provided between the conductor groups 81 arranged in the circumferential direction means that the teeth have a predetermined thickness in the radial direction and a predetermined width in the circumferential direction. It can be said that this is a configuration in which a part of the magnetic circuit, that is, a magnet magnetic path is formed between the magnetic circuits 81. In this regard, a configuration in which the teeth are not provided between the conductive wire groups 81 can be said to be a configuration in which the above-described magnetic circuit is not formed.

及 び As shown in FIGS. 10 and 11, the stator winding 51 is sealed by a sealing portion 57 made of a synthetic resin material as a sealing material. 10, the sealing portion 57 is provided between the conductor groups 81, that is, the gap 56 is filled with a synthetic resin material, and is provided between the conductor groups 81 by the sealing portion 57. And an insulating member interposed therebetween. That is, the sealing portion 57 functions as an insulating member in the gap 56. The sealing portion 57 extends radially outside the stator core 52 in a range that includes all the conductor groups 81, that is, in a range in which the radial thickness is larger than the radial thickness of each conductor group 81. Is provided.

In addition, when viewed in the vertical cross section of FIG. 11, the sealing portion 57 is provided in a range including the turn portion 84 of the stator winding 51. Inside the stator winding 51 in the radial direction, a sealing portion 57 is provided in a range including at least a part of the end face of the stator core 52. In this case, the stator windings 51 are resin-sealed substantially at the ends of the phase windings of the respective phases, that is, substantially entirely except for connection terminals with the inverter circuit.

In the configuration in which the sealing portion 57 is provided in a range including the end face of the stator core 52, the sealing portion 57 can press the laminated steel sheet of the stator core 52 inward in the axial direction. Thereby, the laminated state of each steel plate can be maintained using the sealing portion 57. Although the inner peripheral surface of the stator core 52 is not resin-sealed in the present embodiment, the entire stator core 52 including the inner peripheral surface of the stator core 52 is resin-sealed instead. It may be a configuration.

When the rotating electric machine 10 is used as a vehicle power source, the sealing portion 57 is made of a heat-resistant fluororesin, an epoxy resin, a PPS resin, a PEEK resin, an LCP resin, a silicon resin, a PAI resin, a PI resin, or the like. Preferably, it is configured. Further, considering the coefficient of linear expansion from the viewpoint of suppressing cracking due to the difference in expansion, it is preferable that the material is the same as the outer coating of the conductor of the stator winding 51. That is, a silicone resin whose linear expansion coefficient is generally twice or more that of another resin is desirably excluded. In addition, in an electric product such as an electric vehicle that does not have an engine using combustion, a PPO resin, a phenol resin, and an FRP resin having a heat resistance of about 180 ° C. are also candidates. This is not the case in a field where the ambient temperature of the rotating electric machine can be regarded as being lower than 100 ° C.

ト ル ク The torque of the rotating electric machine 10 is proportional to the magnitude of the magnetic flux. Here, when the stator core has teeth, the maximum magnetic flux amount at the stator is limited depending on the saturation magnetic flux density at the teeth, but the stator core does not have teeth. In such a case, the maximum magnetic flux amount at the stator is not limited. Therefore, the configuration is advantageous in increasing the current flowing through the stator winding 51 to increase the torque of the rotating electric machine 10.

各 Each conductive wire group 81 radially outside the stator core 52 is configured by arranging a plurality of conductive wires 82 having a flat rectangular cross section in a radial direction. Each conductive wire 82 is arranged in a direction that satisfies “radial dimension <circumferential dimension” in a cross section. Thus, the thickness of each conductive wire group 81 in the radial direction is reduced. In addition, the thickness of the conductor region is reduced in the radial direction, and the conductor region extends flat to the region where the teeth are conventionally formed, so that the conductor region has a flat conductor region structure. As a result, an increase in the calorific value of the conductor, which may be caused by a reduction in the cross-sectional area due to the reduction in thickness, is suppressed by flattening in the circumferential direction to increase the cross-sectional area of the conductor. Note that, even in a configuration in which a plurality of conductors are arranged in the circumferential direction and are connected in parallel, an effect based on the same theory can be obtained, although the conductor cross-sectional area is reduced by the conductor coating.

Since there is no slot, in the stator winding 51 in the present embodiment, the conductor region in one circumferential direction can be designed to be larger than the gap region. In the conventional rotating electric machine for a vehicle, it is natural that the conductor area / gap area in one circumferential direction of the stator winding is 1 or less. On the other hand, in the present embodiment, each conductive wire group 81 is provided such that the conductor region is equal to the gap region or the conductor region is larger than the gap region. Here, as shown in FIG. 10, assuming that a conductor region in which the conductor 82 (that is, a straight line portion 83 described later) is disposed in the circumferential direction is WA and a region between conductors between adjacent conductors 82 is WB, The area WA is larger in the circumferential direction than the inter-wire area WB.

ト ル ク The torque of the rotating electric machine 10 is substantially inversely proportional to the radial thickness of the conductor group 81. In this regard, by reducing the thickness of the conductive wire group 81 on the radially outer side of the stator core 52, the configuration is advantageous in increasing the torque of the rotating electric machine 10. The reason is that the distance from the magnet part 42 of the rotor 40 to the stator core 52 (that is, the distance of the part without iron) can be reduced to reduce the magnetic resistance. According to this, the flux linkage of the stator core 52 by the permanent magnet can be increased, and the torque can be increased.

The conductor 82 is made of a covered conductor in which the surface of a conductor 82a is covered with an insulating film 82b, and insulation is ensured between the conductors 82 overlapping each other in the radial direction and between the conductor 82 and the stator core 52. ing. The thickness of the insulating film 82b in the conductor 82 is, for example, 80 μm, which is thicker than the thickness (20 to 40 μm) of a commonly used conductor. Thereby, the insulating property between the conductor 82 and the stator core 52 is ensured without interposing an insulating paper or the like between them. In addition, each of the phase windings constituted by the conductive wires 82 has an insulating property by the insulating coating 82b except for an exposed portion for connection. The exposed portion is, for example, an input / output terminal portion or a neutral point portion in the case of a star connection. In the conductive wire group 81, the conductive wires 82 adjacent to each other in the radial direction are fixed to each other by using a resin fixing or a self-sealing coated wire. This suppresses dielectric breakdown, vibration, and sound due to the rubbing of the conductive wires 82.

In the present embodiment, the conductor 82a is configured as an aggregate of a plurality of strands 86. Specifically, as shown in FIG. 13, the conductor 82a is formed in a twisted yarn shape by twisting a plurality of strands 86. Further, as shown in FIG. 14, the strand 86 is configured as a composite in which thin fibrous conductive materials 87 are bundled. For example, the strand 86 is a composite of CNT (carbon nanotube) fibers, and as the CNT fibers, fibers including boron-containing fine fibers in which at least a part of carbon is replaced by boron are used. As the carbon-based fine fiber, a vapor grown carbon fiber (VGCF) or the like can be used in addition to the CNT fiber, but it is preferable to use the CNT fiber. Note that the surface of the wire 86 is covered with a polymer insulating layer such as enamel, PEEK resin, or PPS resin.

た め Since the plurality of strands 86 are twisted in the conductor 82a, generation of eddy current in each strand 86 is suppressed, and eddy current in the conductor 82a can be reduced. Further, since the strands 86 are twisted, portions where directions of applying the magnetic field are opposite to each other are generated in one strand 86, and the back electromotive voltage is canceled. Therefore, the eddy current can be reduced. In particular, by forming the wire 86 from the fibrous conductive material 87, it is possible to make the wire thinner and to remarkably increase the number of twists, so that the eddy current can be more suitably reduced.

As described above, the conductive wire 82 has a flat rectangular cross section and is arranged in a plurality in the radial direction. For example, a plurality of strands 86 are gathered in a twisted state, and in that state, a synthetic resin or the like is used. It is good to harden it into a desired shape and form it.

Each conductive wire 82 is bent so as to be arranged in a predetermined arrangement pattern in the circumferential direction, whereby a phase winding for each phase is formed as the stator winding 51. As shown in FIG. 12, in the stator winding 51, a coil side portion 53 is formed by a straight portion 83 extending linearly in the axial direction of each of the conductors 82, and is located on both outer sides of the coil side portion 53 in the axial direction. The projecting turn portions 84 form the coil end portions 54 and 55. Each conductor 82 is configured as a series of corrugated conductors by alternately repeating a straight portion 83 and a turn portion 84. The linear portions 83 are arranged at positions facing the magnet portion 42 in the radial direction, and the in-phase linear portions 83 arranged at a predetermined interval at a position outside the magnet portion 42 in the axial direction are: They are connected to each other by a turn part 84. Note that the straight portion 83 corresponds to a “magnet facing portion”.

In the present embodiment, the stator winding 51 is formed in an annular shape by distributed winding. In this case, in the coil side portion 53, linear portions 83 are arranged in the circumferential direction at a pitch corresponding to one pole pair of the magnet portion 42 for each phase, and in the coil end portions 54 and 55, the linear portions 83 for each phase are arranged. Are connected to each other by a turn portion 84 formed in a substantially V shape. The straight portions 83 forming a pair corresponding to one pole pair have current directions opposite to each other. Also, the combination of the pair of linear portions 83 connected by the turn portion 84 is different between the one coil end portion 54 and the other coil end portion 55, and the connection at the coil end portions 54 and 55 is different. By repeating in the circumferential direction, the stator winding 51 is formed in a substantially cylindrical shape.

More specifically, the stator winding 51 constitutes a winding for each phase using two pairs of conducting wires 82 for each phase, and one of the three windings (U Phase, V phase, W phase) and the other three-phase winding (X phase, Y phase, Z phase) are provided in two layers inside and outside in the radial direction. In this case, assuming that the number of phases of the winding is S and the logarithm of the conductor 82 is m, 2 × S × m = 2Sm conductor groups 81 are formed for each pole pair. In the present embodiment, since the number of phases S is 3, the logarithm m is 2, and the rotating electric machine has 8 pole pairs (16 poles), 2 × 3 × 2 × 8 = 96 conductive wire groups 81 are arranged in the circumferential direction. Are located.

In the stator winding 51 shown in FIG. 12, in the coil side portion 53, the linear portions 83 are superposed in two layers on the inner and outer sides in the radial direction, and at the coil end portions 54 and 55, the straight lines 83 on the inner and outer sides in the radial direction overlap. From the part 83, the turn part 84 is configured to extend in the circumferential direction in directions opposite to each other in the circumferential direction. That is, in each of the conductive wires 82 that are adjacent in the radial direction, the directions of the turn portions 84 are opposite to each other except for the portion that becomes the coil end.

Here, the winding structure of the conductor wire 82 in the stator winding 51 will be specifically described. In the present embodiment, a plurality of conductive wires 82 formed by wave winding are provided in a plurality of layers (for example, two layers) inward and outward in the radial direction. FIGS. 15A and 15B are diagrams showing the form of each conductor 82 in the n-th layer. FIG. 15A shows the shape of the conductor 82 viewed from the side of the stator winding 51, and FIG. The shape of the conducting wire 82 as viewed from one axial side of the slave winding 51 is shown. In FIG. 15, positions where the conductive wire group 81 is arranged are indicated as D1, D2, D3,. Also, for convenience of explanation, only three conductive wires 82 are shown, which are a first conductive wire 82_A, a second conductive wire 82_B, and a third conductive wire 82_C.

In each of the conductors 82_A to 82_C, the straight portions 83 are arranged at the position of the nth layer, that is, at the same position in the radial direction, and the straight portions 83 separated from each other by six positions (3 × m pairs) in the circumferential direction. They are connected to each other by a turn part 84. In other words, in each of the conductors 82_A to 82_C, every fifth straight portion 83 is connected to each other by the turn portion 84 on the same pitch circle centered on the axis of the rotor 40. For example, in the first conductive wire 82 </ b> _A, a pair of straight portions 83 are arranged at D <b> 1 and D <b> 7, respectively, and the pair of straight portions 83 are connected by an inverted V-shaped turn portion 84. The other conductors 82_B and 82_C are arranged in the same n-th layer with their circumferential positions shifted one by one. In this case, since each of the conductive wires 82_A to 82_C is disposed in the same layer, the turn portions 84 may interfere with each other. For this reason, in the present embodiment, an interference avoiding portion in which a part thereof is radially offset is formed in the turn portion 84 of each of the conductive wires 82_A to 82_C.

Specifically, the turn portion 84 of each of the conductors 82_A to 82_C has a slope portion 84a extending in the circumferential direction on the same pitch circle, and a radially inner side from the same pitch circle from the slope portion 84a (see FIG. 15 (b), and has a top portion 84b, an inclined portion 84c, and a return portion 84d, which are portions extending in the circumferential direction on another pitch circle. The top portion 84b, the inclined portion 84c, and the return portion 84d correspond to an interference avoiding portion. Note that the inclined portion 84c may be configured to shift radially outward with respect to the inclined portion 84a.

That is, the turn portion 84 of each of the conductors 82_A to 82_C has a slope portion 84a on one side and a slope portion 84c on the other side on both sides of the top portion 84b, which is a central position in the circumferential direction. The radial positions of the inclined portions 84a and 84c (positions in the front-rear direction in FIG. 15A, positions in the up-down direction in FIG. 15B) are different from each other. For example, the turn portion 84 of the first conductive wire 82 </ b> _A extends in the circumferential direction from the position D <b> 1 of the n-layer as a starting point, and bends in the radial direction (for example, radially inward) at the top portion 84 b which is the central position in the circumferential direction. By turning again in the circumferential direction, it extends in the circumferential direction again, and further turns again in the radial direction (for example, radially outward) at the return portion 84d, thereby reaching the D9 position of the n-layer which is the end point position. I have.

According to the above configuration, in each of the conductors 82_A to 82_C, one of the inclined portions 84a is vertically arranged in order from the top in the order of the first conductor 82_A → the second conductor 82_B → the third conductor 82_C, and each of the conductors 82_A ～ 82_C is turned upside down, and the other inclined portions 84c are arranged vertically from the top in the order of the third conductor 82_C → the second conductor 82_B → the first conductor 82_A. Therefore, the conductors 82_A to 82_C can be arranged in the circumferential direction without interfering with each other.

Here, in a configuration in which a plurality of conductive wires 82 are superposed in the radial direction to form a conductive wire group 81, a turn portion 84 connected to the radially inner straight portion 83 of the plurality of linear portions 83 and a radially outer straight portion 83 are formed. It is preferable that the turn portions 84 connected to the straight portions 83 are arranged further apart from each other in the radial direction than the straight portions 83. Further, when a plurality of layers of the conductive wires 82 are bent to the same side in the radial direction near the end of the turn portion 84, that is, near the boundary with the linear portion 83, the insulation between the conductive wires 82 of the adjacent layers is caused by the interference. Should not be impaired.

For example, in D7 to D9 of FIG. 15, the respective conducting wires 82 overlapping in the radial direction are bent in the radial direction at the return portion 84d of the turn portion 84, respectively. In this case, as shown in FIG. 16, it is preferable to make the bending radius of the bent portion different between the n-th conductive wire 82 and the (n + 1) -th conductive wire 82. Specifically, the bending radius R1 of the radially inner (n-th layer) conductive wire 82 is made smaller than the bending radius R2 of the radially outer (n + 1-th layer) conductive wire 82.

シ フ ト Further, it is preferable that the amount of shift in the radial direction be different between the n-th conductive wire 82 and the (n + 1) -th conductive wire 82. Specifically, the shift amount S1 of the radially inner (n-th layer) conductive wire 82 is made larger than the shift amount S2 of the radially outer (n + 1-th layer) conductive wire 82.

According to the above configuration, even when the conductive wires 82 overlapping in the radial direction are bent in the same direction, mutual interference between the conductive wires 82 can be preferably avoided. Thereby, good insulating properties are obtained.

Next, the structure of the magnet portion 42 in the rotor 40 will be described. In the present embodiment, it is assumed that the permanent magnet has a residual magnetic flux density Br = 1.0 [T] and a coercive force bHc = 400 [kA / m] or more. Since 5000 to 10000 [AT] is applied by inter-phase excitation, if a permanent magnet of 25 [mm] is used for one pole pair, bHc = 10000 [A], indicating that no demagnetization occurs. Here, in the present embodiment, since a permanent magnet whose easy axis of magnetization is controlled by the orientation is used, the length of the magnetic circuit inside the magnet is conventionally set to 1.0 [T] or more. It can be longer than the circuit length. In other words, a magnetic circuit length per pole pair can be achieved with a small amount of magnets, and the reversible demagnetization range is maintained even when exposed to severe high-temperature conditions, compared to a design using conventional linearly-oriented magnets. Can be. In addition, the inventor of the present application has found a configuration that can obtain characteristics close to those of a polar anisotropic magnet even when a conventional magnet is used.

As shown in FIGS. 8 and 9, the magnet portion 42 has an annular shape and is provided inside the rotor main body 41 (specifically, inside the magnet holding portion 43 in the radial direction). The magnet section 42 is a polar anisotropic magnet and has a first magnet 91 and a second magnet 92 having different magnetic poles. The first magnets 91 and the second magnets 92 are alternately arranged in the circumferential direction. The first magnet 91 is an N-pole magnet in the rotor 40, and the second magnet 92 is an S-pole magnet in the rotor 40. The first magnet 91 and the second magnet 92 are permanent magnets made of a rare earth magnet such as a neodymium magnet.

磁石 In each of the magnets 91 and 92, the magnetization direction extends in an arc between the d axis which is the center of the magnetic pole and the q axis which is the boundary of the magnetic pole. In each of the magnets 91 and 92, the magnetization direction is the radial direction on the d-axis side, and the circumferential direction is the circumferential direction on the q-axis side. In the magnet section 42, the magnetic flux flows in an arc between the adjacent N and S poles by the magnets 91 and 92, so that the magnet magnetic path is longer than, for example, a radial anisotropic magnet. Therefore, as shown in FIG. 17, the magnetic flux density distribution becomes close to a sine wave. As a result, unlike the magnetic flux density distribution of the radial anisotropic magnet shown as a comparative example in FIG. 18, the magnetic flux can be concentrated at the magnetic pole position, and the torque of the rotating electric machine 10 can be increased. 17 and 18, the horizontal axis represents the electrical angle, and the vertical axis represents the magnetic flux density. 17 and 18, 90 ° on the horizontal axis indicates the d-axis (that is, the center of the magnetic pole), and 0 ° and 180 ° on the horizontal axis indicate the q-axis.

The sine wave matching ratio of the magnetic flux density distribution may be, for example, 40% or more. In this way, the amount of magnetic flux in the center portion of the waveform can be reliably improved as compared with the case of using a radially oriented magnet or a parallelly oriented magnet having a sine wave matching ratio of about 30%. Further, when the sine wave matching ratio is set to 60% or more, the amount of magnetic flux at the center portion of the waveform can be reliably improved as compared with the magnetic flux concentrated array called the Halbach array.

で は In the comparative example shown in FIG. 18, the magnetic flux density changes sharply near the q-axis. As the change in the magnetic flux density becomes steeper, the eddy current generated in the stator winding 51 increases. On the other hand, in the present embodiment, the magnetic flux density distribution is close to a sine wave. For this reason, near the q-axis, the change in the magnetic flux density is smaller than the change in the magnetic flux density of the radial anisotropic magnet. Thereby, generation of eddy current can be suppressed.

By the way, in the magnet portion 42, a magnetic flux is generated in the direction orthogonal to the magnetic pole surface near the d-axis of each of the magnets 91 and 92 (that is, the magnetic pole center). Make an arc. Further, the magnetic flux that is perpendicular to the magnetic pole surface becomes a strong magnetic flux. In this regard, in the rotating electric machine 10 of the present embodiment, since the conductor groups 81 are thinned in the radial direction as described above, the radial center position of the conductor groups 81 approaches the magnetic pole surface of the magnet part 42 and is fixed. The child 50 can receive a strong magnet magnetic flux from the rotor 40.

固定 Further, the stator 50 is provided with a cylindrical stator core 52 radially inside the stator winding 51, that is, on the opposite side of the rotor 40 with the stator winding 51 interposed therebetween. Therefore, the magnetic flux extending from the magnetic pole surfaces of the magnets 91 and 92 is attracted to the stator core 52 and orbits while using the stator core 52 as a part of the magnetic path. In this case, the direction and path of the magnet magnetic flux can be optimized.

Next, the configuration of a control system that controls the rotating electric machine 10 will be described. FIG. 19 is an electric circuit diagram of a control system of the rotating electric machine 10, and FIG. 20 is a functional block diagram illustrating a control process performed by the control device 110.

In FIG. 19, two sets of three- phase windings 51a and 51b are shown as the stator winding 51. The three-phase winding 51a includes a U-phase winding, a V-phase winding, and a W-phase winding. The phase winding 51b includes an X-phase winding, a Y-phase winding, and a Z-phase winding. A first inverter 101 and a second inverter 102 are provided for each of the three- phase windings 51a and 51b. The inverters 101 and 102 are configured by full-bridge circuits having the same number of upper and lower arms as the number of phases of the phase windings, and the switches (semiconductor switching elements) provided on each arm are turned on and off to turn the stator windings 51 on and off. The conduction current is adjusted in each phase winding.

直流 A DC power supply 103 and a smoothing capacitor 104 are connected in parallel to each of the inverters 101 and 102. The DC power supply 103 is configured by, for example, an assembled battery in which a plurality of cells are connected in series. Each switch of the inverters 101 and 102 corresponds to the semiconductor module 66 shown in FIG. 1 and the like, and the capacitor 104 corresponds to the capacitor module 68 shown in FIG. 1 and the like.

The control device 110 includes a microcomputer including a CPU and various memories. Based on various detection information in the rotating electric machine 10 and requests for powering drive and power generation, the control of the power supply is performed by turning on and off the switches in the inverters 101 and 102. carry out. Control device 110 corresponds to control device 77 shown in FIG. The detection information of the rotating electric machine 10 includes, for example, a rotation angle (electrical angle information) of the rotor 40 detected by an angle detector such as a resolver, a power supply voltage (inverter input voltage) detected by a voltage sensor, and a current sensor. , The energized current of each phase detected by Control device 110 generates and outputs an operation signal for operating each switch of inverters 101 and 102. The power generation request is, for example, a request for regenerative driving when the rotating electric machine 10 is used as a vehicle power source.

The first inverter 101 includes a series connection of an upper arm switch Sp and a lower arm switch Sn in three phases including a U phase, a V phase, and a W phase. The high potential side terminal of the upper arm switch Sp of each phase is connected to the positive terminal of the DC power supply 103, and the low potential side terminal of the lower arm switch Sn of each phase is connected to the negative terminal (ground) of the DC power supply 103. . One end of each of a U-phase winding, a V-phase winding, and a W-phase winding is connected to an intermediate connection point between the upper arm switch Sp and the lower arm switch Sn of each phase. These phase windings are star-connected (Y connection), and the other ends of the phase windings are connected to each other at a neutral point.

The second inverter 102 has a configuration similar to that of the first inverter 101, and includes a series connection of an upper arm switch Sp and a lower arm switch Sn in three phases including an X phase, a Y phase, and a Z phase. ing. The high potential side terminal of the upper arm switch Sp of each phase is connected to the positive terminal of the DC power supply 103, and the low potential side terminal of the lower arm switch Sn of each phase is connected to the negative terminal (ground) of the DC power supply 103. . One end of each of an X-phase winding, a Y-phase winding, and a Z-phase winding is connected to an intermediate connection point between the upper arm switch Sp and the lower arm switch Sn of each phase. These phase windings are star-connected (Y connection), and the other ends of the phase windings are connected to each other at a neutral point.

FIG. 20 shows a current feedback control process for controlling the U, V, and W phase currents, and a current feedback control process for controlling the X, Y, and Z phase currents. Here, the control process on the U, V, and W phases will be described first.

20, a current command value setting unit 111 uses a torque-dq map and based on a powering torque command value or a power generation torque command value for the rotating electric machine 10 and an electric angular velocity ω obtained by time-differentiating the electric angle θ. , A d-axis current command value and a q-axis current command value are set. The current command value setting unit 111 is provided in common on the U, V, and W phase sides and the X, Y, and Z phase sides. The power generation torque command value is, for example, a regenerative torque command value when the rotating electric machine 10 is used as a vehicle power source.

The dq conversion unit 112 converts a current detection value (each phase current) obtained by a current sensor provided for each phase into a d-axis current and a q-axis current which are components of an orthogonal two-dimensional rotating coordinate system having the field direction as a d-axis. And convert to

The d-axis current feedback control unit 113 calculates a d-axis command voltage as an operation amount for feedback-controlling the d-axis current to a d-axis current command value. Further, the q-axis current feedback control unit 114 calculates a q-axis command voltage as an operation amount for feedback-controlling the q-axis current to a q-axis current command value. In each of these feedback control units 113 and 114, the command voltage is calculated using the PI feedback method based on the deviation of the d-axis current and the q-axis current from the current command value.

The three-phase converter 115 converts d-axis and q-axis command voltages into U-phase, V-phase, and W-phase command voltages. Each of the units 111 to 115 is a feedback control unit that performs feedback control of the fundamental wave current based on the dq conversion theory, and the U-phase, V-phase, and W-phase command voltages are feedback control values.

Then, the operation signal generation unit 116 generates an operation signal for the first inverter 101 based on the three-phase command voltage using a known triangular wave carrier comparison method. Specifically, the operation signal generation unit 116 performs a PWM control based on a magnitude comparison between a signal obtained by standardizing a three-phase command voltage with a power supply voltage and a carrier signal such as a triangular wave signal, and thereby switches the upper and lower arms in each phase. An operation signal (duty signal) is generated.

The X, Y, and Z phase sides have the same configuration, and the dq conversion unit 122 outputs a current detection value (each phase current) obtained by a current sensor provided for each phase to a field direction of d. It is converted into a d-axis current and a q-axis current which are components of an orthogonal two-dimensional rotating coordinate system as axes.

The d-axis current feedback control unit 123 calculates a d-axis command voltage, and the q-axis current feedback control unit 124 calculates a q-axis command voltage. The three-phase converter 125 converts d-axis and q-axis command voltages into X-phase, Y-phase, and Z-phase command voltages. Then, the operation signal generation unit 126 generates an operation signal for the second inverter 102 based on the three-phase command voltage. Specifically, the operation signal generation unit 126 performs a PWM control based on a magnitude comparison between a signal obtained by standardizing a three-phase command voltage with a power supply voltage and a carrier signal such as a triangular wave signal, and thereby switches the upper and lower arms in each phase. An operation signal (duty signal) is generated.

The driver 117 turns on and off the three-phase switches Sp and Sn of the inverters 101 and 102 based on the switch operation signals generated by the operation signal generation units 116 and 126.

Next, the torque feedback control process will be described. This process is used mainly for the purpose of increasing the output of the rotating electric machine 10 and reducing the loss under operating conditions in which the output voltage of each of the inverters 101 and 102 becomes large, such as in a high rotation region and a high output region. The control device 110 selects and executes one of the torque feedback control process and the current feedback control process based on the operating conditions of the rotating electric machine 10.

FIG. 21 shows a torque feedback control process corresponding to the U, V, and W phases and a torque feedback control process corresponding to the X, Y, and Z phases. In FIG. 21, the same components as those in FIG. 20 are denoted by the same reference numerals, and description thereof will be omitted. Here, the control process on the U, V, and W phases will be described first.

The voltage amplitude calculation unit 127 is a command value for the magnitude of the voltage vector based on the powering torque command value or the power generation torque command value for the rotary electric machine 10 and the electrical angular velocity ω obtained by time-differentiating the electrical angle θ. Calculate the voltage amplitude command.

The torque estimation unit 128a calculates a torque estimation value corresponding to the U, V, and W phases based on the d-axis current and the q-axis current converted by the dq conversion unit 112. Note that the torque estimating unit 128a may calculate the voltage amplitude command based on the map information in which the d-axis current, the q-axis current, and the voltage amplitude command are related.

The torque feedback control unit 129a calculates a voltage phase command, which is a command value of a voltage vector phase, as an operation amount for performing feedback control of a torque estimation value to a powering torque command value or a power generation torque command value. The torque feedback control unit 129a calculates a voltage phase command using a PI feedback method based on the deviation of the estimated torque value from the powering torque command value or the generated torque command value.

The operation signal generation unit 130a generates an operation signal for the first inverter 101 based on the voltage amplitude command, the voltage phase command, and the electrical angle θ. Specifically, the operation signal generation unit 130a calculates a three-phase command voltage based on the voltage amplitude command, the voltage phase command, and the electrical angle θ, and standardizes the calculated three-phase command voltage with the power supply voltage. And PWM control based on a magnitude comparison between the signal and a carrier signal such as a triangular wave signal to generate switch operation signals for the upper and lower arms in each phase.

Incidentally, the operation signal generation unit 130a is based on a pulse pattern information, a voltage amplitude command, a voltage phase command, and an electrical angle θ, which are map information in which the voltage amplitude command, the voltage phase command, the electric angle θ and the switch operation signal are related. Thus, a switch operation signal may be generated.

The X-, Y-, and Z-phase sides also have the same configuration, and the torque estimating unit 128b determines the X, Y, and Z-axis currents based on the d-axis current and the q-axis current converted by the dq An estimated torque value corresponding to the Z phase is calculated.

The torque feedback control unit 129b calculates a voltage phase command as an operation amount for feedback-controlling the torque estimation value to the powering torque command value or the power generation torque command value. The torque feedback control unit 129b calculates the voltage phase command using the PI feedback method based on the deviation of the estimated torque value from the powering torque command value or the generated torque command value.

The operation signal generator 130b generates an operation signal for the second inverter 102 based on the voltage amplitude command, the voltage phase command, and the electrical angle θ. Specifically, the operation signal generation unit 130b calculates a three-phase command voltage based on the voltage amplitude command, the voltage phase command, and the electrical angle θ, and standardizes the calculated three-phase command voltage with the power supply voltage. And PWM control based on a magnitude comparison between the signal and a carrier signal such as a triangular wave signal to generate switch operation signals for the upper and lower arms in each phase. The driver 117 turns on and off the three-phase switches Sp and Sn in the inverters 101 and 102 based on the switch operation signals generated by the operation signal generation units 130a and 130b.

Incidentally, the operation signal generation unit 130b is based on the voltage amplitude command, the voltage phase command, the pulse pattern information that is the map information associated with the electrical angle θ and the switch operation signal, the voltage amplitude command, the voltage phase command, and the electrical angle θ. Thus, a switch operation signal may be generated.

According to the embodiment described in detail above, the following excellent effects can be obtained.

In the stator 50, the teeth made of the soft magnetic material are not provided between the linear portions 83 adjacent in the circumferential direction of the stator winding 51 (that is, between the adjacent magnet facing portions). According to the above configuration, the conductor cross-sectional area can be increased by bringing the adjacent linear portions 83 closer to each other, as compared with the case where the teeth are provided between the linear portions 83. Heat generated due to energization can be reduced. In a so-called slotless structure in which no teeth are provided between the straight portions 83, the absence of teeth between the straight portions 83 can eliminate magnetic saturation and increase the current flowing through the stator winding 51. It becomes possible. In this case, it is possible to suitably cope with an increase in the amount of heat generated with an increase in the supplied current. As described above, it is possible to optimize the heat radiation performance of the stator 50.

The stator core 52 is assembled to the stator winding 51, and in the assembled state, no teeth made of a soft magnetic material are provided between the linear portions 83 adjacent in the circumferential direction. In this case, the stator core 52 provided on the opposite side in the radial direction with respect to the rotor 40 functions as a back yoke, so that an appropriate magnetic circuit can be provided even if no teeth exist between the linear portions 83. Can be formed.

(4) The stator winding 51 is sealed with a sealing material, so that an insulating member is provided between the linear portions 83 circumferentially adjacent to each other in the stator winding 51. Thereby, even if the respective linear portions 83 are arranged at positions close to each other in the circumferential direction, it is possible to secure good insulation properties in the linear portions 83.

た め In the stator winding 51, the conducting wire 82 is flattened and the radial thickness of the straight portion 83 is reduced, so that the radial center position of the straight portion 83 can be closer to the magnet portion 42 of the rotor 40. Accordingly, it is possible to increase the magnetic flux density in the linear portion 83 of the stator winding 51 and to increase the torque while suppressing the magnetic saturation in the stator 50 by adopting the slotless structure. Further, as described above, since the linear portions 83 adjacent to each other in the circumferential direction can be brought closer to each other, the conductor cross-sectional area can be ensured even when the conducting wire 82 is flat.

た め Since each conductor 82 of the stator winding 51 is an aggregate of a plurality of strands 86, the current flow path in the conductor 82 can be made thinner. Accordingly, even when an eddy current is generated when the magnetic field from the magnet portion 42 is linked to the conducting wire 82, an eddy current suppressing effect of the conducting wire 82 against the eddy current can be obtained. As a result, eddy current flowing through the conductive wire 82 can be reduced.

Further, since each conducting wire 82 is configured by twisting the strands 86, there are portions where the directions of applying the magnetic field are opposite to each other in each strand 86, and the back electromotive voltage caused by the interlinking magnetic field cancels out. Is done. As a result, the effect of reducing the eddy current flowing through the conductive wire 82 can be enhanced.

た め Since each strand 86 is made of the fibrous conductive material 87, the current flow path in the conductor 82 can be made thinner, and the number of twists of the current flow path can be increased. Thereby, the effect of reducing the eddy current can be enhanced. Note that the strand 86 is preferably made of at least carbon nanotube fiber.

In the stator 50 having the slotless structure, the conductor area WA can be extended in the circumferential direction as compared with the inter-wire area WB because the teeth are not provided in the stator core 52. Accordingly, a configuration in which the conductor region WA is larger than the inter-conductor region WB in the circumferential direction can be suitably realized.

Since the turn portion 84 of the stator winding 51 is shifted in the radial direction and has an interference avoiding portion that avoids interference with another turn portion 84, different turn portions 84 are arranged apart from each other in the radial direction. Can be. Thereby, the heat radiation of the turn portion 84 can be improved, and the heat radiation performance of the stator 50 can be further enhanced.

As a configuration for avoiding mutual interference at the turn portions 84 of the respective conductors 82 on the same pitch circle of the stator 50, the turn portions 84 are inclined portions 84a (portions extending in the circumferential direction on the same pitch circle). And a top portion 84b, a slope portion 84c, and a return portion 84d that are shifted radially inward from the same pitch circle from the inclined portion 84a and extend in the circumferential direction on another pitch circle. (Corresponding to two parts). Thereby, mutual interference in the turn portion 84 can be properly avoided.

Among the straight portions 83 of the plurality of layers, the turn portion 84 connected to the radially inner straight portion 83 and the turn portion 84 connected to the radially outer straight portion 83 are smaller in diameter than the straight portions 83. The heat dissipating performance of the turn portion 84 can be improved because the heat dissipating member is disposed apart from the direction.

Since the bending radius of the bent portion in the turn portion 84 is different between the turn portion 84 connected to the radially inner straight portion 83 and the turn portion 84 connected to the radially outer straight portion 83, each of these turns is different. The portions 84 can be suitably spaced.

In the turn portion 84, the amount of radial shift from the straight portion 83 in the bent portion is determined by the turn portion 84 connected to the radially inner straight portion 83 and the turn portion 84 connected to the radially outer straight portion 83. Due to the difference, the respective turn portions 84 can be suitably separated from each other.

Hereinafter, a detailed structure of the stator 50 of the present embodiment will be described with reference to FIGS. In FIG. 31, the stator 50 includes a stator winding 51 outside a stator core 52. The stator winding 51 includes a coil side portion 53 and coil end portions 54 and 55. The coil side portion 53 is opposed to the magnet portion 42 of the rotor 40 and extends straight along the magnet portion 42 in the axial direction.

The coil end portions 54 and 55 have a plurality of turn portions 84 bent toward the side opposite to the magnet portion 42 of the rotor 40, and the turn portions 84 overlap each other in the axial direction of the rotating shaft 11. In other words, in the stator winding 51, the coil end portions 54 and 55 are bent radially inward along the stator core 52, and the stator core 52 is formed by the coil end portion 54 and the coil end portion 55. It is configured to sandwich it.

Of the coil end portions 54, 55, a part of the turn portion 84 forming the coil end portion 54, which is located on a side farther from the end plate portion 63, has a diameter of the rotating shaft 11 larger than the inner peripheral surface of the stator core 52. It is located inside the direction. In other words, in the turn portion 84 forming the coil end portion 54, the turn portions 84 having different shapes are shifted from each other in the radial direction, and there are a portion overlapping each other in the axial direction and a portion not overlapping.

On the other hand, of the coil end portions 54 and 55, the turn portions 84 forming the coil end portions 55 located closer to the end plate portion 63 have the same radial projection amount. In other words, the turn portions 84 forming the coil end portion 55 do not shift from each other in the radial direction, and the portion where the turn portions 84 overlap each other in the axial direction in the entire coil end portion 55 forms the coil end portion 54. More than in the turn section 84. The coil end portion 55 is located radially outward of the rotating shaft 11 from the inner peripheral surface of the annular stator core 52. The coil end portion 54 and the coil end portion 55 have asymmetric shapes.

固定 The stator winding 51 having a large radial projection in the coil end portion 54 has a small axial projection in the coil end portion 55. On the other hand, the stator winding 51 having a small amount of protrusion in the radial direction at the coil end portion 54 has a large amount of protrusion in the axial direction at the coil end portion 55. That is, the length of the stator winding 51 including the coil end portion 54 and the coil end portion 55 is substantially equal to each other.

ケ ー シ ン グ The casing portion 64 that holds the stator core 52 from the radial inside is a cylindrical shape extending in the axial direction. A casing portion 64 is located radially inside the coil end portion 55. In other words, on the coil end portion 55 side, the casing portion 64 is provided to protrude longer in the axial direction than the stator core 52. On the other hand, the casing 64 is not located radially inside the coil end 54. In other words, on the coil end portion 54 side, the end in the axial direction of the casing portion 64 is flush with the end in the axial direction of the stator core 52, and extends in the axial direction with respect to the stator core 52. The extension height is zero. Therefore, the casing portion 64 has a higher extension height in the axial direction with respect to the stator core 52 on the coil end portion 55 side than on the coil end portion 54 side.

In FIG. 32, the stator 50 includes stator windings 51 for three phases of U-phase, V-phase, and W-phase outside the annular stator core 52. That is, the stator winding 51 includes a U-phase stator winding 51U that is a U-phase winding, a V-phase stator winding 51V that is a V-phase winding, and a W-phase stator that is a W-phase winding. It is formed by three types of phase windings including a winding 51W. In the following description, in order to distinguish the turn part 84 on the coil end part 54 side and the turn part 84 on the coil end part 55 side in the following description, the turn part 84 will be referred to as a turn part 841 or a turn part 846. The description will be made using two symbols. That is, among the coil end portions 54 and 55, the turn portion 84 on the coil end portion 54 side located farther from the end plate portion 63 is denoted by the reference numeral of the turn portion 841. On the other hand, among the coil end portions 54 and 55, the turn portion 84 on the coil end portion 55 side located closer to the end plate portion 63 is denoted by the reference numeral of the turn portion 846.

The turn portion 841 is a U-phase turn portion 841U that is a turn portion 841 in the U-phase stator winding 51U, a V-phase turn portion 841V that is a V-phase turn portion 841, and a W phase that is a turn portion 841 in the W phase. A turn portion 841W is provided. Similarly to the turn portion 841, the turn portion 846 has three types of a U-phase turn portion 846U, a V-phase turn portion 846V, and a W-phase turn portion 846W. Similarly to the turn part 841, the coil side part 53 has three types of a U-phase coil side part 53U, a V-phase coil side part 53V, and a W-phase coil side part 53W.

The U-phase stator winding 51U includes a U-phase coil side portion 53U and U-phase turn portions 841U and 846U. The V-phase stator winding 51V includes a V-phase coil side portion 53V and V- phase turn portions 841V and 846V. The W-phase stator winding 51W includes a W-phase coil side portion 53W and W- phase turn portions 841W and 846W.

The U-phase stator winding 51U, the V-phase stator winding 51V, and the W-phase stator winding 51W are arranged in a circumferential direction so that the stator windings 51 of the same phase do not contact each other on the outer peripheral surface of the stator core 52. They are arranged regularly every predetermined number. That is, in the circumferential direction of the stator 50, the V-phase stator winding 51V and the W-phase stator winding 51W are arranged adjacent to the U-phase stator winding 51U. A U-phase stator winding 51U and a W-phase stator winding 51W are arranged adjacent to the V-phase stator winding 51V. A U-phase stator winding 51U and a V-phase stator winding 51V are arranged adjacent to the W-phase stator winding 51W. Therefore, the U-phase stator windings 51U are provided in the stator 50 at equal intervals in the circumferential direction. The V-phase stator windings 51V are provided in the stator 50 at equal intervals in the circumferential direction. The W-phase stator windings 51W are provided at equal intervals in the circumferential direction on the stator 50.

に 関 し て Regarding the length of the conductor wire 82 of the stator winding 51 of each phase, the longest U-phase stator winding 51U of the turn portion 841 has the shortest turn portion 846. On the other hand, the shortest W-phase stator winding 51W of the turn portion 841 has the longest turn portion 846. That is, the conductor length of the U-phase stator winding 51U, the conductor length of the V-phase stator winding 51V, and the conductor length of the W-phase stator winding 51W are equal to each other. The U-phase stator winding 51U, the V-phase stator winding 51V, and the W-phase stator winding 51W have the same thickness. However, it is not necessary that the stator windings 51 of each phase have strictly equal lengths and thicknesses. I just need.

に お い て In FIG. 33, the conductor group 81 forming the turn portion 841 is constituted by four conductors 82 arranged in the radial direction. That is, the U-phase turn part 841U is configured in the order of the first U-phase turn part 841U1, the second U-phase turn part 841U2, the third U-phase turn part 841U3, and the fourth U-phase turn part 841U4 in the direction from the radial outside to the radial inside. Have been. Similarly to the U-phase turn part 841U, the V-phase turn part 841V includes a first V-phase turn part 841V1, a second V-phase turn part 841V2, a third V-phase turn part 841V3, and a fourth V in a direction from the radial outside to the radial inside. The phase turn portions 841V4 are configured in this order. Similarly to the U-phase turn portion 841U, the W-phase turn portion 841W includes a first W-phase turn portion 841W1, a second W-phase turn portion 841W2, a third W-phase turn portion 841W3, and a fourth W in a direction from the radial outside to the radial inside. The phase turn portions 841W4 are configured in this order. The conductor group 81 and the conductor 82 together provide a conductor part.

The conducting wire 82 forming the turn portion 841 includes two inclined portions 841a which are portions extending radially inward, a top portion 841b which is a portion extending in the circumferential direction, and two corner portions connecting the inclined portions 841a and 841b. 841e. The turn portion 841 has a U-shape having an open end radially outward.

In the turn portion 841, the U-phase turn portion 841U is located closer to the stator core 52 in the axial direction than the V-phase turn portion 841V and the W-phase turn portion 841W. That is, the U-phase turn portion 841U provides the innermost turn portion located at the innermost layer among the turn portions 841.

On the other hand, the V-phase turn portion 841V and the W-phase turn portion 841W are located axially outward, which is a direction farther from the stator core 52 than the U-phase turn portion 841U. That is, the V-phase turn part 841V and the W-phase turn part 841W provide an outer layer turn part. Further, the W-phase turn portion 841W, which is the outer layer turn portion, is located axially outside the U-phase turn portion 841U and the V-phase turn portion 841V. That is, the W-phase turn portion 841W provides the outermost turn portion located at the outermost layer among the turn portions 841. Further, the V-phase turn portion 841V that is the outer layer turn portion is located between the U-phase turn portion 841U that is the innermost turn portion and the W-phase turn portion 841W that is the outermost layer turn portion. That is, the V-phase turn part 841V provides a middle turn part located in a middle layer between the innermost layer and the outermost layer of the turn part 841.

In FIG. 34, for the U-phase turn portion 841U, which is the innermost turn portion, the maximum protrusion amount of the U-phase turn portion 841U, which is the distance from the radially outermost position to the radially innermost position, is indicated by the innermost layer maximum protrusion amount LU. Have been. Regarding the V-phase turn portion 841V that is the middle turn portion, the maximum protrusion amount of the V-phase turn portion 841V that is the distance from the radially outermost position to the radially innermost position is indicated by the middle-layer maximum protrusion amount LV. For the W-phase turn portion 841W, which is the outermost layer turn portion, the maximum protrusion amount of the W-phase turn portion 841W, which is the distance from the radially outermost position to the radially innermost position, is indicated by the outermost layer maximum protrusion amount LW.

内 The innermost layer maximum protrusion amount LU is larger than the middle layer maximum protrusion amount LV. The outermost layer maximum protrusion amount LW is smaller than the middle layer maximum protrusion amount LV. That is, the radial protrusion amount of the turn portion 841 is the largest in the innermost layer maximum protrusion amount LU, and the smallest in the outermost layer maximum protrusion amount LW.

Here, the protruding amount means a length that protrudes in the radial direction with reference to the outer peripheral surface of the stator core 52, which is the surface on which the coil side portion 53 is located. Further, the protruding amount is an amount determined for each conducting wire 82 forming the turn portion 841, and in the U-phase turn portion 841U, the first U-phase turn portion 841U1, the second U-phase turn portion 841U2, and the third U-phase turn portion 841U3 The fourth U-phase turn portion 841U4 has a different protrusion amount. The innermost layer maximum protrusion amount LU is equal to the protrusion amount in the fourth U-phase turn portion 841U4. The middle layer maximum protrusion amount LV is equal to the protrusion amount in the fourth V-phase turn portion 841V4. The outermost layer maximum protrusion amount LW is equal to the protrusion amount in the fourth W-phase turn portion 841W4.

In FIG. 33, the amount of radial protrusion of the second U-phase turn portion 841U2 in the U-phase turn portion 841U is substantially equal to the thickness of the stator core 52 in the radial direction. The radial projection of the first U-phase turn 841U1 is smaller than the second U-phase turn 841U2 by the thickness of the first U-phase turn 841U1.

The amount of radial protrusion of the third U-phase turn portion 841U3 is about twice the radial thickness of the stator core 52. That is, the radially projecting amount of the third U-phase turn portion 841U3 is larger than the thickness dimension of the stator core 52. Therefore, at least a portion of the U-phase turn portion 841U protrudes radially inward from the inner peripheral surface of the stator core 52. The amount of radial protrusion of the fourth U-phase turn portion 841U4 is greater than that of the third U-phase turn portion 841U3 by the thickness of the fourth U-phase turn portion 841U4.

径 The amount of radial protrusion of the second U-phase turn portion 841U2 is smaller than the amount of radial protrusion of the third U-phase turn portion 841U3. That is, the first U-phase turn portion 841U1 and the second U-phase turn portion 841U2 provide a small turn portion having a small protrusion amount. On the other hand, the third U-phase turn portion 841U3 and the fourth U-phase turn portion 841U4 provide a large turn portion having a large protrusion amount.

Similarly to the U-phase turn portion 841U, the V-phase turn portion 841V includes a first V-phase turn portion 841V1 and a second V-phase turn portion 841V2 as small turn portions, and a third V-phase turn portion 841V3 and a fourth V-phase turn portion 841V4. Is a large turn section. However, the radially projecting amounts of the third V-phase turn portion 841V3 and the fourth V-phase turn portion 841V4, which are the large turn portions of the V-phase turn portion 841V, are equal to the third U-phase turn portion 841U3, the fourth U-phase turn portion 841U4, and Is smaller than the amount of protrusion in the radial direction. On the other hand, the amount of protrusion of the second V-phase turn portion 841V2 in the radial direction is substantially equal to the amount of protrusion of the second U-phase turn portion 841U2 in the radial direction.

空 A gap is formed between the large turn part and the small turn part. That is, the second U-phase turn part 841U2 and the third U-phase turn part 841U3 are radially separated from each other, and a gap is formed between the second U-phase turn part 841U2 and the third U-phase turn part 841U3. . Also, a gap is formed between the second V-phase turn part 841V2 and the third V-phase turn part 841V3. The size of the gap between the second V-phase turn part 841V2 and the third V-phase turn part 841V3 in the V-phase turn part 841V depends on the size of the gap between the second U-phase turn part 841U2 and the third U-phase turn part 841U3 in the U-phase turn part 841U. It is smaller than the size of the gap between them.

In the 相 W-phase turn portion 841W, the amount of protrusion of the second W-phase turn portion 841W2 and the amount of protrusion of the third W-phase turn portion 841W3 differ by the thickness of the conductive wire 82. That is, the gap formed between the second W-phase turn portion 841W2 and the third W-phase turn portion 841W3 is extremely small. In other words, the size of the gap between the second W-phase turn part 841W2 and the third W-phase turn part 841W3 in the W-phase turn part 841W is the second V-phase turn part 841V2 and the third V-phase turn part in the V-phase turn part 841V. 841 V3, which is smaller than the size of the gap.

In FIG. 35, the radius of curvature Ra on the outside of the bend of the corner 841e of the second V-phase turn portion 841V2, which is a small turn portion, and the radius of curvature Rb on the inside of the bend of the corner 841e of the third V-phase turn portion 841V3, which is a large turn portion. Is a different size. The radius of curvature Ra is the same size outside the bends of the two corners 841e in the second V-phase turn 841V2. The radius of curvature Rb is the same size inside the two corners 841e of the third V-phase turn 841V3. The corners 841e that define the radius of curvature Ra and the radius of curvature Rb face each other. Here, assuming that no gap is formed between the second V-phase turn portion 841V2 and the third V-phase turn portion 841V3, and the conductive wires 82 are in contact with each other without any gap, the curvature radius Ra and the curvature radius are assumed. Rb has the same size. That is, in the V-phase turn portion 841V, a gap is generated between the second V-phase turn portion 841V2 and the third V-phase turn portion 841V3 by changing the size of the radius of curvature Ra and the radius of curvature Rb.

In the V-phase turn portion 841V, the radius of curvature Ra is larger than the radius of curvature Rb. That is, the second V-phase turn portion 841V2 is bent so as to draw a gentler curve than the third V-phase turn portion 841V3. Thereby, in the V-phase turn portion 841V, a gap can be formed, and the four conductive wires 82 can be bent and turned without difficulty. Also in the U-phase turn portion 841U, the second U-phase turn portion 841U2 is bent with a large radius of curvature so as to draw a gentler curve than the third U-phase turn portion 841U3, similarly to the V-phase turn portion 841V.

(4) The amount of protrusion in the radial direction of the first U-phase turn portion 841U1 is equal to the amount of protrusion in the radial direction of the first V-phase turn portion 841V1. The amount of protrusion in the radial direction at the second U-phase turn portion 841U2 is equal to the amount of protrusion in the radial direction of the second V-phase turn portion 841V2. The protrusion amount of the fourth W-phase turn portion 841W4 is smaller than the protrusion amount of the first V-phase turn portion 841V1. Therefore, the top portion 841b of the W-phase turn portion 841W is provided at a position radially displaced from the top portion 841b of the U-phase turn portion 841U and the top portion 841b of the V-phase turn portion 841V. In other words, the top portion 841b of the W-phase turn portion 841W does not axially overlap the top portion 841b of the other turn portion 841.

(4) The heat radiation in the coil end portion 54 will be described below. Heat is generated in the stator windings 51 due to energization. This heat causes the temperature of the stator winding 51 to rise. However, as the temperature of the stator windings 51 rises, the temperature difference between the stator windings 51 and the air around the stator windings 51 increases, so that the heat of the stator windings 51 is actively radiated into the air. Here, the amount of heat radiated from the stator winding 51 to the air varies depending on the size of the contact area between the stator winding 51 and the surrounding air. That is, in the portion of the stator winding 51 having a large contact area with the air, the heat of the stator winding 51 is actively radiated into the air, so that the temperature does not easily rise. On the other hand, in the portion of the stator winding 51 having a small contact area with air, heat is hardly dissipated into the air, and the temperature is likely to rise due to heat retention. Therefore, in order to improve the heat dissipation performance from the stator winding 51, it is necessary to make the low temperature air and the stator winding 51 contact as much as possible.

The coil end portion 54 has three types of turn portions 841 including a U-phase turn portion 841U as an innermost turn portion, a V-phase turn portion 841V as an intermediate turn portion, and a W-phase turn portion 841W as an outermost turn portion. It is constituted by. Here, assuming that the three types of turn portions 841 of the U-phase turn portion 841U, the V-phase turn portion 841V, and the W-phase turn portion 841W are not displaced from each other in the radial direction, and the protrusion amounts in the radial direction are equal to each other. Is assumed. In this case, there is no member that hinders contact with air outside the W-phase turn portion 841W, which is the outermost turn portion, and the contact area with air is large as compared with the other turn portions 841 and the heat radiation performance is high. . On the other hand, the U-phase turn portion 841U, which is the innermost turn portion, has the stator core 52 disposed inside, the V-phase turn portion 841V, which is the middle turn portion, and the W-phase turn portion, which is the outermost turn portion, outside. 841W. For this reason, there are members on both sides of the inside and outside of the U-phase turn portion 841U that hinder contact with air. Therefore, the heat radiation performance of the U-phase turn portion 841U tends to be lower than at least the W-phase turn portion 841W.

However, in the turn portion 841, the amount of radial protrusion of the U-phase turn portion 841U, the amount of radial protrusion of the V-phase turn portion 841V, and the amount of radial protrusion of the W-phase turn portion 841W are different. The protrusion amounts are different from each other. In other words, three types of turn portions 841 of the U-phase turn portion 841U, the V-phase turn portion 841V, and the W-phase turn portion 841W are arranged to be shifted from each other in the radial direction. Therefore, at least a portion of the U-phase turn portion 841U, which is the innermost turn portion, is a portion where no other turn portion 841 is arranged outside. Similarly, the V-phase turn portion 841V, which is the middle turn portion, has a portion on the outside where no other turn portion 841 is arranged. Therefore, the U-phase turn portion 841U, which is the innermost turn portion, and the V-phase turn portion 841V, which is the middle turn portion, provide a heat dissipation promoting turn portion 841 having a portion where heat dissipation to the air is promoted. Also, the amount of the W-phase turn portion 841W overlapping the other turn portions 841 in the axial direction is small. In other words, the contact area with the air inside the W-phase turn portion 841W in the axial direction is large. Therefore, the W-phase turn portion 841W provides a heat dissipation promoting turn portion 841 in which heat dissipation is promoted.

Further, a gap is formed between the second U-phase turn portion 841U2 and the third U-phase turn portion 841U3 forming the U-phase turn portion 841U. It is assumed that no gap is formed between the second U-phase turn portion 841U2 and the third U-phase turn portion 841U3. In this case, air flowing around the U-phase turn portion 841U cannot enter between the four conducting wires 82 forming the U-phase turn portion 841U. That is, the area where the second U-phase turn portion 841U2 and the third U-phase turn portion 841U3 are in contact with each other cannot be included in the contact area between the U-phase turn portion 841U and air. However, in the U-phase turn portion 841U, a gap is formed between the second U-phase turn portion 841U2 and the third U-phase turn portion 841U3. Therefore, air can enter between the second U-phase turn part 841U2 and the third U-phase turn part 841U3. That is, the area of the portion where the second U-phase turn portion 841U2 and the third U-phase turn portion 841U3 face each other can be included in the contact area between the U-phase turn portion 841U and air. Therefore, it is easy to secure a large contact area with the air in the U-phase turn portion 841U.

に お い て In FIG. 31, when the rotor 40 rotates, wind is generated inside the rotating electric machine 10. Part of the generated wind flows along the stator 50 located inside the rotor 40. At this time, in the coil end portions 54 and 55, the flow of the wind differs depending on the portion. That is, the passage of the wind is more restricted in the coil end portion 55 in which the casing portion 64 holding the stator core 52 is greatly extended in the axial direction, and the wind is less likely to flow. On the other hand, the coil end portion 54 has fewer members obstructing the flow of the wind as compared with the coil end portion 55, and more wind can easily flow. Therefore, the coil end portion 54 farther from the end plate portion 63 tends to contribute to the improvement of the heat radiation performance of the stator winding 51 than the coil end portion 55 closer to the end plate portion 63. In other words, the shape of the turn portion 841 forming the coil end portion 54 having a shape having a high heat dissipation performance is better than the shape of the turn portion 846 forming the coil end portion 55 having a shape having a high heat dissipation performance. The heat radiation performance of the entire wire 51 can be improved. However, the shape of the heat radiation performance of both the turn portions 841 and 846 is higher in the whole stator winding 51 than the shape of the heat radiation performance of only one of the turn portions 841 and 846. Easy to enhance heat dissipation performance.

According to the above-described embodiment, the radially projecting amount of the U-phase turn portion 841U as the innermost turn portion is the radially projecting amount of the V-phase turn portion 841V and the W-phase turn portion 841W as the outer layer turn portion. The projection amount is different from that of FIG. In other words, the U-phase turn portion 841U has many portions that do not axially overlap the V-phase turn portion 841V and the W-phase turn portion 841W. Therefore, as compared with the case where the U-phase turn portion 841U overlaps the other turn portion 841 in the axial direction, a larger contact area with the air can be ensured, and the wind generated by the rotation of the rotor 40 in the vicinity can be secured. Since the passage is improved, the heat radiation into the air in the U-phase turn portion 841U can be promoted. Also, in the V-phase turn portion 841V and the W-phase turn portion 841W, the heat radiation to the air can be promoted in the same manner as the U-phase turn portion 841U. Therefore, it is easy to suppress an abnormal temperature rise in the turn portion 841 and to exert appropriate performance of the rotating electric machine 10. In particular, it is very important for the rotary electric machine 10 to operate properly that the heat radiation into the air in the U-phase turn part 841U located in the innermost layer where the heat is most likely to be stored among the turn parts 841 is very important. It is.

The U-phase turn portion 841U has a gap between a small turn portion such as the second U-phase turn portion 841U2 and a large turn portion such as the third U-phase turn portion 841U3. Therefore, a large contact area between the air flowing around the U-phase turn portion 841U and the U-phase turn portion 841U can be ensured. Therefore, the heat radiation performance of the U-phase turn portion 841U can be improved. Further, also in the V-phase turn portion 841V and the W-phase turn portion 841W, heat radiation into the air can be promoted by providing a gap similarly to the U-phase turn portion 841U.

空 A gap in the U-phase turn portion 841U as the innermost turn portion is larger than a gap in the V-phase turn portion 841V and the W-phase turn portion 841W as the outer layer turn portions. For this reason, the heat radiation performance in the U-phase turn portion 841U located in the innermost layer where the heat is most likely to be stored is increased, and the temperature in the U-phase stator winding 51U is higher than the temperatures in the other stator windings 51. It is easy to prevent it from becoming too high.

The radius of curvature Ra at the corner 841e of the second V-phase turn portion 841V2, which is a small turn portion, is larger than the radius of curvature Rb at the corner portion 841e of the third V-phase turn portion 841V3, which is a large turn portion. Therefore, in the V-phase turn portion 841V, a gap is easily formed between the second V-phase turn portion 841V2 and the third V-phase turn portion 841V3. That is, in the turn portion 841 configured by bending the plurality of conducting wires 82, the conducting wire 82 can be turned without difficulty, and an excessive load is suppressed from being applied to the corner portion 841e, and the properly turned state is maintained. It's easy to do.

Only one of the turn portions 84 provided on both sides in the axial direction is the heat radiation promoting turn portion 841. In other words, the turn portions 84 provided on both sides in the axial direction have asymmetric shapes. For this reason, the orientation of the stator 50 can be more easily recognized as compared with the case where both sides of the turn portion 84 are the heat dissipation promoting turn portions 841. Therefore, when assembling the components constituting the rotating electric machine 10, it is easy to prevent the components from being erroneously assembled in the correct orientation. In addition, a high degree of freedom in designing the stator winding 51 can be ensured.

The heat dissipation promoting turn portion 841 is a turn portion 841 on the side where the extension height of a portion of the casing portion 64 that is axially outside the stator core 52 in the turn portions 84 on both axial sides of the stator core 52 is smaller. It is provided in. For this reason, the heat radiation can be promoted in the turn portion 841 in which the flow of the air is hardly hindered by the casing portion 64. Therefore, a greater heat dissipation promoting effect can be easily obtained than when the same type of heat dissipation promoting turn portion 841 is provided on the turn portion 846 side opposite to the turn portion 841.

(4) The resistance value of the U-phase stator winding 51U, the resistance value of the V-phase stator winding 51V, and the resistance value of the W-phase stator winding 51W are equal to each other. That is, the conductor lengths and the thicknesses of the different-phase stator windings 51 are equal to each other. For this reason, the resistance values of the different-phase stator windings 51 can be made equal to each other, and the amount of heat generated between the different-phase stator windings 51 when the conducting wire 82 is energized can be made equal. Therefore, only the heat value of the specific stator winding 51 is abnormally large, and it is easy to suppress that the specific portion of the stator winding 51 becomes abnormally high in temperature.

The innermost layer maximum protrusion amount LU in the radial direction of the U-phase turn portion 841U, which is the innermost turn portion, is determined by the radially intermediate maximum layer protrusion amount LV of the V-phase turn portion 841V and the radial direction of the W-phase turn portion 841W. It is larger than the outermost layer maximum protrusion amount LW. Therefore, heat dissipation can be promoted not only at the top portion 841b of the U-phase turn portion 841U but also at the inclined portion 841a. Therefore, the heat radiation performance of the U-phase turn portion 841U located in the innermost layer where heat is most likely to be stored is easily increased.

の 中 The radially-directed maximum layer protrusion amount LV in the V-phase turn portion 841V is larger than the radially outermost layer maximum protrusion amount LW in the W-phase turn portion 841W. Furthermore, the radially innermost layer maximum protrusion amount LU of the U-phase turn portion 841U is larger than the radially middle layer maximum protrusion amount LV of the V-phase turn portion 841V. In other words, the radially protruding amount of the heat radiation promoting turn portion 841 is set to be larger in the order in which heat is more likely to accumulate. For this reason, by improving the heat radiation performance of the heat radiation promotion turn part 841 as the stator winding 51 is located on the axially inner side where the heat is easily stored, the temperature difference of each part in the entire stator winding 51 is reduced. It can be suppressed from becoming too large.

Ｕ The innermost layer maximum protrusion amount LU in the U-phase turn portion 841U forming the heat dissipation promotion turn portion 841 is larger than the thickness dimension of the stator core 52. For this reason, it becomes possible to prevent the air from becoming difficult to flow due to the stator core 52 being positioned inside the U-phase turn portion 841U in the axial direction. Therefore, it is easy to have a configuration in which air actively flows on both the axially outer side and the axially inner side of the U-phase turn portion 841U. Therefore, it is easy to enhance the heat radiation performance in the U-phase turn portion 841U.

In the U-phase turn portion 841U, a gap may be formed other than between the second U-phase turn portion 841U2 and the third U-phase turn portion 841U3. For example, a gap may be formed between the first U-phase turn part 841U1 and the second U-phase turn part 841U2. Further, a plurality of gaps may be formed in the U-phase turn section 841U by forming a gap between the third U-phase turn section 841U3 and the fourth U-phase turn section 841U4. According to this, it is possible to secure a large number of gaps in the U-phase turn portion 841U. That is, instead of forming one large-sized gap, three small-sized gaps can be formed, so that a large gap can be secured in the U-phase turn portion 841U. Therefore, the heat radiation performance of the U-phase turn portion 841U can be improved. Here, forming a plurality of voids is applicable to the turn portions 841 other than the U-phase turn portion 841U.

詳細 The detailed structure of the stator 50 described above is a configuration applicable not only to the first embodiment but also to all embodiments.

Hereinafter, another embodiment will be described focusing on differences from the first embodiment.

(2nd Embodiment)
In the present embodiment, the pole anisotropic structure of the magnet portion 42 in the rotor 40 is changed, and will be described in detail below.

及 び As shown in FIGS. 22 and 23, the magnet unit 42 is configured using a magnet array called a Halbach array. That is, the magnet part 42 has the first magnet 131 whose magnetization direction (direction of the magnetic pole) is the radial direction, and the second magnet 132 whose magnetization direction (the direction of the magnetic pole) is the circumferential direction. The first magnets 131 are arranged at predetermined intervals, and the second magnets 132 are arranged at positions between the adjacent first magnets 131 in the circumferential direction. The first magnet 131 and the second magnet 132 are permanent magnets made of a rare earth magnet such as a neodymium magnet.

The first magnets 131 are circumferentially separated from each other such that the poles on the side facing the stator 50 (inside in the radial direction) alternately become N poles and S poles. The second magnets 132 are arranged so that the magnetic poles in the circumferential direction are alternately opposite to each other next to the first magnets 131.

磁性 Further, a magnetic body 133 made of a soft magnetic material is disposed radially outside the first magnet 131, that is, on the side of the magnet holding portion 43 of the rotor main body 41. For example, the magnetic body 133 may be made of an electromagnetic steel sheet, soft iron, or a powdered iron core material. In this case, the circumferential length of the magnetic body 133 is the same as the circumferential length of the first magnet 131 (in particular, the circumferential length of the outer peripheral portion of the first magnet 131). Further, the radial thickness of the integrated body in a state where the first magnet 131 and the magnetic body 133 are integrated is the same as the radial thickness of the second magnet 132. In other words, the thickness of the first magnet 131 in the radial direction is smaller than that of the second magnet 132 by the amount of the magnetic body 133. The magnets 131 and 132 and the magnetic body 133 are fixed to each other by, for example, an adhesive. The outer side of the first magnet 131 in the magnet portion 42 in the radial direction is on the opposite side to the stator 50, and the magnetic body 133 is located on the opposite side of the first magnet 131 in the radial direction (opposite to the stator 50). On the stator side).

キ ー A key 134 is formed on the outer periphery of the magnetic body 133 as a protrusion projecting radially outward, that is, toward the magnet holding portion 43 of the rotor main body 41. Further, a key groove 135 is formed on the inner peripheral surface of the magnet holding portion 43 as a recess for accommodating the key 134 of the magnetic body 133. The protruding shape of the key 134 and the groove shape of the key groove 135 are the same, and the same number of key grooves 135 as the keys 134 are formed corresponding to the keys 134 formed on each magnetic body 133. By the engagement of the key 134 and the key groove 135, the positional displacement of the first magnet 131 and the second magnet 132 and the rotor main body 41 in the circumferential direction (rotation direction) is suppressed. The key 134 and the key groove 135 (the convex portion and the concave portion) may be provided in any of the magnet holding portion 43 and the magnetic body 133 of the rotor main body 41, and conversely, the outer periphery of the magnetic body 133 may be provided. It is also possible to provide a key groove 135 in the portion and to provide a key 134 in the inner peripheral portion of the magnet holding portion 43 of the rotor main body 41.

Here, in the magnet unit 42, the magnetic flux density in the first magnet 131 can be increased by alternately arranging the first magnets 131 and the second magnets 132. Therefore, in the magnet section 42, the magnetic flux is concentrated on one side, and the magnetic flux on the side closer to the stator 50 can be enhanced.

Further, by arranging the magnetic body 133 radially outside the first magnet 131, that is, on the side opposite to the stator, it is possible to suppress partial magnetic saturation outside the first magnet 131 in the radial direction, and as a result, magnetic saturation occurs. The demagnetization of the first magnet 131 generated as a result can be suppressed. As a result, it is possible to increase the magnetic force of the magnet part 42. In other words, the magnet section 42 of the present embodiment has a configuration in which a portion of the first magnet 131 where demagnetization easily occurs is replaced with a magnetic body 133.

FIGS. 24A and 24B are diagrams specifically showing the flow of the magnetic flux in the magnet unit 42. FIG. 24A shows a case where a conventional configuration having no magnetic body 133 in the magnet unit 42 is used, and FIG. The case where the configuration of the present embodiment having the magnetic body 133 in the magnet section 42 is used is shown. In FIG. 24, the magnet holding portion 43 and the magnet portion 42 of the rotor main body 41 are linearly developed, and the lower side of the figure is the stator side and the upper side is the non-stator side.

In the configuration of FIG. 24A, the magnetic pole surface of the first magnet 131 and the side surface of the second magnet 132 are in contact with the inner peripheral surface of the magnet holder 43, respectively. Further, the magnetic pole surface of the second magnet 132 is in contact with the side surface of the first magnet 131. In this case, the magnetic flux F <b> 1 entering the contact surface with the first magnet 131 through the outer path of the second magnet 132 and the magnetic flux F <b> 1 substantially parallel to the magnet A composite magnetic flux is generated with the magnetic flux that attracts F2. Therefore, there is a concern that magnetic saturation may partially occur near the contact surface between the first magnet 131 and the second magnet 132 in the magnet holding unit 43.

On the other hand, in the configuration of FIG. 24B, the magnetic body 133 is provided between the magnetic pole surface of the first magnet 131 and the inner peripheral surface of the magnet holding portion 43 on the side opposite to the stator of the first magnet 131. Therefore, the passage of magnetic flux through the magnetic body 133 is allowed. Therefore, magnetic saturation in the magnet holding portion 43 can be suppressed, and the proof strength against demagnetization is improved.

Furthermore, in the configuration of FIG. 24B, unlike FIG. 24A, F2 that promotes magnetic saturation can be eliminated. Thereby, the permeance of the entire magnetic circuit can be effectively improved. With this configuration, the magnetic circuit characteristics can be maintained even under severe high-temperature conditions.

磁石 In addition, compared to the radial magnet in the conventional SPM rotor, the magnet magnetic path passing inside the magnet is longer. Therefore, the magnet permeance increases, the magnetic force can be increased, and the torque can be increased. Further, since the magnetic flux is concentrated at the center of the d-axis, the sine wave matching ratio can be increased. In particular, when the current waveform is changed to a sine wave or a trapezoidal wave by the PWM control, or a switching IC with 120-degree conduction is used, the torque can be more effectively increased.

(Other embodiments)
The above embodiment may be changed as follows, for example.

(4) In the above embodiment, the outer peripheral surface of the stator core 52 is formed into a curved surface without irregularities, and the plurality of conductor groups 81 are arranged at predetermined intervals on the outer peripheral surface. However, this may be changed. For example, as shown in FIG. 25, the stator core 52 includes an annular yoke portion 141 provided on the opposite side (lower side in the figure) to the rotor among the radially opposite sides of the stator winding 51, A projection 142 extends from the yoke 141 so as to project between the linear portions 83 adjacent in the circumferential direction. The protrusions 142 are provided at predetermined intervals on a radially outer side of the yoke 141, that is, on the rotor 40 side. Each conductive wire group 81 of the stator winding 51 is engaged with the protrusion 142 in the circumferential direction, and is arranged side by side in the circumferential direction while using the protrusion 142 as a positioning portion. The protrusion 142 corresponds to an “inter-winding member”. The protrusion 142 provides an inter-wire member.

The protrusion 142 has a thickness in the radial direction from the yoke 141, which is a radial thickness of the linear part 83 radially adjacent to the yoke 141, of the linear parts 83 in a plurality of layers inside and outside the radial direction. (H1 in the figure). Due to the thickness limitation of the protrusions 142, the protrusions 142 do not function as teeth between the conductive wire groups 81 (that is, the linear portions 83) that are adjacent in the circumferential direction, and no magnetic path is formed by the teeth. . The protrusions 142 may not be provided entirely between the conductor groups 81 arranged in the circumferential direction, but may be provided between at least one set of conductor groups 81 adjacent in the circumferential direction. The shape of the protrusion 142 may be an arbitrary shape such as a rectangular shape or an arc shape.

直線 Further, on the outer peripheral surface of the stator core 52, a single linear portion 83 may be provided. Therefore, in a broad sense, the thickness of the projection 142 in the radial direction from the yoke 141 may be smaller than half the thickness of the straight portion 83 in the radial direction.

Assuming a virtual circle centered on the axis of the rotating shaft 11 and passing through the radial center of the linear portion 83 radially adjacent to the yoke portion 141, the protrusion 142 is within the range of the virtual circle. In this case, it is preferable to form a shape that protrudes from the yoke portion 141, in other words, a shape that does not protrude radially outward from the virtual circle (ie, toward the rotor 40).

According to the above configuration, the thickness of the protrusion 142 in the radial direction is limited and does not function as a tooth between the linear portions 83 adjacent in the circumferential direction. Is provided, adjacent linear portions 83 can be brought closer to each other. Thereby, the conductor cross-sectional area can be increased, and the heat generated due to the energization of the stator winding 51 can be reduced. In such a configuration, magnetic saturation can be eliminated by the absence of teeth, and the current flowing through the stator winding 51 can be increased. In this case, it is possible to suitably cope with an increase in the amount of heat generated with an increase in the supplied current. Further, in the stator winding 51, since the turn portion 84 is shifted in the radial direction and has an interference avoiding portion that avoids interference with another turn portion 84, the different turn portions 84 are separated from each other in the radial direction. Can be arranged. Thereby, the heat radiation of the turn portion 84 can be improved. As described above, it is possible to optimize the heat radiation performance of the stator 50.

If the yoke 141 of the stator core 52 and the magnets 42 of the rotor 40 (that is, the magnets 91 and 92) are separated by a predetermined distance or more, the radial thickness of the protrusion 142 is It is not tied to 25 H1. Specifically, if the yoke 141 and the magnet 42 are separated by 2 mm or more, the radial thickness of the protrusion 142 may be H1 or more in FIG. For example, when the thickness of the straight portion 83 in the radial direction exceeds 2 mm and the conductor group 81 is constituted by two layers of conductors 82 inside and outside in the radial direction, the straight portion 83 not adjacent to the yoke portion 141 That is, the protrusion 142 may be provided in a range from the yoke 141 to half the position of the second-layer conductive wire 82 counted. In this case, if the radial thickness of the protrusion 142 is up to “H1 × 3/2”, the above-described effect can be obtained to a considerable extent by increasing the conductor cross-sectional area in the conductor group 81. .

The stator core 52 may have the configuration shown in FIG. Although the sealing portion 57 is omitted in FIG. 26, the sealing portion 57 may be provided. In FIG. 26, for convenience, the magnet part 42 and the stator core 52 are linearly developed and shown.

In the configuration of FIG. 26, the stator 50 has a protrusion 142 as an inter-winding member between the conductors 82 (that is, the straight portions 83) adjacent in the circumferential direction. Here, in the range of one pole of the magnet part 42, the circumferential width of the protrusion 142 which is excited by energization of the stator winding 51 is Wt, the saturation magnetic flux density of the protrusion 142 is Bs, When the circumferential width of one pole is Wm and the residual magnetic flux density of the magnet part 42 is Br, the protrusion 142 is formed by Wt × Bs ≦ Wm × Br
… (1)
And a magnetic material.

More specifically, in the present embodiment, the three-phase winding of the stator winding 51 is a distributed winding, and in the stator winding 51, the number of protrusions 142, The number of the gaps 56 between the conductive wire groups 81 is “3 × m”. Here, m is the logarithm of the conductor 82. In this case, when the stator winding 51 is energized in a predetermined order for each phase, the projections 142 for two phases are excited within one pole. Therefore, in the range of one pole of the magnet portion 42, the circumferential width Wt of the protrusion 142 that is excited by the conduction of the stator winding 51 is equal to the circumferential width of the protrusion 142 (that is, the gap 56). Is A, “2 × A × m” is obtained. After the width Wt is defined in this way, the protrusions 142 of the stator core 52 are formed of a magnetic material satisfying the above-described relationship (1). Note that the width dimension Wt is also a circumferential dimension of a portion where relative magnetic permeability can be larger than 1 in one pole.

When the stator winding 51 is a concentrated winding, in the stator winding 51, the number of the protrusions 142, that is, each conductive wire group 81 is provided for one pole pair (that is, two poles) of the magnet portion 42. The number of gaps 56 between them is “3 × m”. In this case, when the stator winding 51 is energized in a predetermined order for each phase, the projections 142 for one phase are excited within one pole. Therefore, the width Wt in the circumferential direction of the protrusion 142 that is excited by energization of the stator winding 51 in the range of one pole of the magnet part 42 is “A × m”. After the width Wt is defined in this manner, the protrusion 142 is formed of a magnetic material satisfying the relationship (1).

Incidentally, magnets having a BH product of 20 [MGOe (kJ / m ＾ 3)] or more, such as neodymium magnets, samarium cobalt magnets, and ferrite magnets, have Bd = 1.0 or more [T], and iron has Br = 2.0 or more [T]. ]. Therefore, as the high-output motor, the protrusion 142 in the stator core 52 may be a magnetic material that satisfies the relationship of Wt <１ ／ × Wm.

In the above-described embodiment, the sealing portion 57 covering the stator winding 51 is provided in the range including all the conductor groups 81 on the radially outer side of the stator core 52, that is, the thickness dimension in the radial direction is equal to that of each conductor group 81. Although the configuration is provided in a range that is larger than the thickness dimension in the radial direction, the configuration may be changed. For example, as shown in FIG. 27, the sealing portion 57 is provided so that a part of the conductive wire 82 protrudes. More specifically, the sealing portion 57 is configured to be provided in a state in which a part of the conductor 82 that is the outermost in the radial direction in the conductor group 81 is exposed to the radial outside, that is, to the stator 50 side. In this case, the radial thickness of the sealing portion 57 is preferably the same as or smaller than the radial thickness of each conductive wire group 81.

· As shown in FIG. 28, the configuration may be such that each conductive wire group 81 is not sealed by the sealing portion 57. That is, the configuration is such that the sealing portion 57 that covers the stator winding 51 is not used. In this case, there is a gap between the conductor groups 81 arranged in the circumferential direction. The configuration in which a gap is formed between the conductor groups 81 arranged in the circumferential direction is a configuration in which the stator winding 51 is formed only by the conductor group 81, and the conductor such as the sealing portion 57 is provided between the conductor groups 81. Provided is a configuration in which no intervening member is provided.

The stator 50 may not have the stator core 52. In this case, the stator 50 is constituted by the stator winding 51 shown in FIG. In the stator 50 having no stator core 52, the stator winding 51 may be sealed with a sealing material. Alternatively, the stator 50 may include an annular winding holding portion made of a nonmagnetic material such as a synthetic resin, instead of the stator core 52 made of a soft magnetic material.

In the conductor group 81 of the stator winding 51, as shown in FIG. 29 (a), as a configuration for avoiding interference between the conductors 82 overlapping inward and outward in the radial direction, a turn portion is formed between the nth layer and the (n + 1) th layer. The configuration may be such that the direction of the wire shift at 84 is reversed. In other words, the turn portions 84 connected to the linear portions 83 of the plurality of layers and located at positions overlapping inward and outward in the radial direction are configured to be bent in different radial directions. Thus, the turn portions 84 can be suitably arranged to be separated from each other. Note that it is preferable that the present configuration is applied to a portion where insulation is strictest or is used as a final layer or a start layer among a plurality of layers.

Alternatively, as shown in FIG. 29B, the n-th layer and the (n + 1) -th layer may have a configuration in which the conductive wire shift position in the axial direction (the vertical position in the drawing) is different. In this case, even if the bending radius at the turn portion 84 of each layer is the same, mutual interference can be suppressed.

In the above embodiment, in the stator winding 51, the straight portions 83 at positions on the same pitch circle centered on the rotating shaft 11 are connected to each other by the turn portion 84, and the turn portion 84 serves as an interference avoiding portion. Although the configuration is provided, this may be changed. For example, in the stator winding 51, a configuration may be used in which the linear portions 83 at positions on different pitch circles around the rotation axis 11, that is, the linear portions 83 in different layers are connected by the turn portion 84. . In any case, any configuration may be used as long as the turn portion 84 is shifted in the radial direction and has an interference avoiding portion that avoids interference with another turn portion 84.

As shown in FIG. 30A, in the conductor group 81 of the stator winding 51, a pair of opposing surfaces of the straight portions 83 of the conductors 82 that face each other in the radial direction (vertical direction in the drawing) are non-parallel. It is good also as composition arranged in the state where it becomes. In FIG. 30A, each conductive wire group 81 is sealed by the sealing portion 57. According to this configuration, a sealing material as a non-heat generating portion can be interposed between the linear portions 83 arranged in the radial direction. The heat generated at 83 can be diffused. Thereby, the heat radiation performance of the conductor group 81 can be improved.

Further, even if the teeth are not interposed between the linear portions 83 adjacent in the circumferential direction, the sealing material is preferably inserted between the linear portions 83 in each of the conductive wire groups 81, and thus each The straight portion 83 can be fixed well. However, in the configuration of FIG. 30A, a configuration in which the sealing portion 57 is not provided may be employed. In this case, a gap as a non-heat generating portion can be interposed between the linear portions 83 arranged in the radial direction, and the heat radiation performance of the conductor group 81 can also be improved.

-As shown in Fig. 30 (b), in the conductor group 81 of the stator 50, the linear portions 83 of the conductors 82 are arranged in four layers in the radially inner and outer layers, and the gap between the pair of opposing surfaces is changed in the circumferential direction. A configuration may be adopted in which the size is different and the larger side is alternately reversed in each of the gaps arranged in the radial direction. In FIG. 30B, each conductive wire group 81 is sealed by the sealing portion 57. The number of layers of the linear portion 83 may be three or more. According to this configuration, heat can be appropriately diffused in each of the linear portions 83 arranged in the radial direction.

Also, even when the rotating direction is switched between forward and reverse during the operation of the rotating electric machine 10 and the motor rotates, the holding force for holding the linear portions 83 can be satisfactorily obtained.

(4) In the stator winding 51, the linear portion 83 of the conducting wire 82 may be provided in a single layer in the radial direction. When the linear portion 83 is arranged in a plurality of layers inside and outside in the radial direction, the number of the layers may be arbitrary, and three, four, five, six, or the like may be provided.

In the above-described embodiment, the rotating shaft 11 is provided so as to protrude at both the one end side and the other end side of the rotating electric machine 10 in the axial direction. However, the configuration may be modified so that the rotating shaft 11 protrudes only at one end side. . In this case, the rotating shaft 11 may be provided so as to extend from the portion supported by the bearing portion 20 in a cantilevered manner to the outside in the axial direction. In this configuration, since the rotation shaft 11 does not protrude into the inverter unit 60, the internal space of the inverter unit 60, more specifically, the internal space of the tubular portion 71 can be used more widely.

(4) As a configuration for rotatably supporting the rotating shaft 11, a configuration may be adopted in which bearings are provided at two locations on one end side and the other end side of the rotor 40 in the axial direction. In this case, in the configuration of FIG. 1, it is preferable that bearings are provided at two locations, one end side and the other end side, with the inverter unit 60 interposed therebetween.

In the above embodiment, the intermediate portion 45 of the rotor main body 41 in the rotor 40 is configured to have a step in the axial direction. However, this may be changed to eliminate the step of the intermediate portion 45 and make the intermediate portion 45 flat.

In the above embodiment, the conductor 82 a in the conductor 82 of the stator winding 51 is configured as an aggregate of a plurality of strands 86, but this configuration may be modified to use a rectangular conductor having a rectangular cross section as the conductor 82. Good. Further, a configuration may be used in which a round conductor having a circular cross section or an elliptical cross section is used as the conductor 82.

In the above embodiment, the inverter unit 60 is provided radially inside the stator 50. However, the inverter unit 60 may not be provided radially inside the stator 50 instead. In this case, it is possible to leave an internal region radially inside the stator 50 as a space. Further, it is possible to arrange components different from the inverter unit 60 in the internal area.

The rotating electric machine 10 may be configured without the housing 30. In this case, for example, the rotor 40, the stator 50, and the like may be held in a part of a wheel or another vehicle part.

The present disclosure is also applicable to a rotating electric machine having an inner rotor structure (adduction structure). In this case, for example, the stator 50 and the rotor 40 may be provided in the housing 30 in order from the outside in the radial direction, and the inverter unit 60 may be provided inside the rotor 40 in the radial direction. In the above embodiment, the SPM rotor has been described as the rotor, but the present invention is also applicable to an IPM rotor. In this case, the straight portion 83 provides a magnet facing portion disposed to face the magnet portion 42 with a predetermined air gap and a rotor core (not shown) interposed therebetween.

Note that the disclosure in this specification is not limited to the illustrated embodiment. The disclosure includes the illustrated embodiments and variations based thereon based on those skilled in the art. For example, the disclosure is not limited to the combination of parts and / or elements shown in the embodiments. The disclosure can be implemented in various combinations. The disclosure may have additional parts that can be added to the embodiments. The disclosure encompasses embodiments that omit parts and / or elements. The disclosure encompasses the replacement or combination of parts and / or elements between one embodiment and another. The disclosed technical scope is not limited to the description of the embodiments. Some of the disclosed technical ranges are indicated by the description of the claims, and should be construed to include all modifications within the meaning and scope equivalent to the description of the claims.

Claims (12)

1. An annular stator core (52);
   A plurality of stator windings (51) covered with an insulating coating (82b);
   A stator (50) arranged coaxially with a rotatably supported rotor (40),
   The stator winding includes:
   A magnet facing portion (83) radially facing the magnet portion (42) of the rotor in the rotating shaft of the rotating electric machine;
   A turn portion (84) connecting the magnet opposing portions in the same phase to each other at an axially outer side of the rotating shaft than the magnet opposing portion;
   At least one of the turn portions provided on both sides in the axial direction is a heat radiation promoting turn portion (841),
   The heat dissipation promoting turn portion,
   The different phases of the heat radiation promoting turn portions are provided so as to partially overlap in the axial direction, and project in the radial direction with respect to the magnet facing portion,
   An innermost turn part (841U) provided at a position closest to the stator core in the axial direction, of the heat dissipation promoting turn parts of different phases overlapping in the axial direction;
   Outer turn portions (841V, 841W) provided at positions farther from the stator core than the innermost turn portions in the axial direction;
   The stator of the rotating electric machine, wherein an amount of protrusion of the innermost turn portion in the radial direction is different from an amount of protrusion of the outer layer turn portion in the radial direction.
2. The stator winding has two or more wires (82) in phase;
   In the same phase, the heat-dissipation-promoting turn portion has a small turn portion (841U2, 841V2, 841W2) having a small amount of protrusion in the radial direction, and a large turn portion (841) having a larger amount of protrusion in the radial direction than the small turn portion. 841U3, 841V3, 841W3).
   2. The stator of the rotating electric machine according to claim 1, wherein a gap is provided between the small turn portion and the large turn portion in the radial direction. 3.
3. The stator of the rotating electric machine according to claim 2, wherein the gap in the innermost turn portion is larger than the gap in the outer turn portion.
4. In the small turn portion and the large turn portion facing each other in the radial direction, the radius of curvature (Ra) outside the bend of the corner (841e) of the small turn portion is determined by the bending of the corner of the large turn portion. The stator for a rotating electrical machine according to claim 2 or 3, wherein the stator is larger than a radius of curvature (Rb) on the inner side.
5. 5. The stator of the rotating electric machine according to claim 1, wherein only one of the turn portions on both sides in the axial direction is the heat-dissipating turn portion.
6. The stator core is held by a casing (64) provided to extend outward in the axial direction from the stator core,
   The heat dissipation promoting turn portion has an extension height, which is the height of a portion of the turn portion on both sides in the axial direction of the stator core, the portion being axially outside the stator core in the casing portion. The stator of the rotating electric machine according to claim 5, wherein the stator is provided on the smaller turn portion.
7. 7. The stator of the rotating electric machine according to claim 1, wherein resistance values of the stator windings having different phases are equal to each other. 8.
8. The maximum protruding amount (LU) of the innermost turn portion in the radial direction is greater than the maximum protruding amount (LV, LW) of the outer turn portion in the radial direction. The stator of the rotary electric machine according to claim 1.
9. The outer layer turn portion,
   An outermost layer turn portion (841W) provided at a position farthest from the stator core among the heat dissipation promoting turn portions overlapping in the axial direction;
   A middle turn part (841V) provided between the outermost turn part and the innermost turn part;
   The maximum protrusion amount (LV) of the middle turn portion in the radial direction is larger than the maximum protrusion amount (LW) of the outermost turn portion in the radial direction, and the maximum turn amount (LW) of the innermost turn portion in the radial direction. 9. The stator of the rotating electric machine according to claim 8, wherein a maximum protrusion amount (LU) is larger than a maximum protrusion amount (LV) of the middle turn portion in the radial direction.
10. The stator of the rotating electric machine according to any one of claims 1 to 9, wherein a maximum protrusion amount (LU) of the heat radiation promotion turn portion in the radial direction is larger than a thickness dimension of the stator core.
11. The stator winding (51) has conductor portions (81, 82) arranged at predetermined positions in a circumferential direction of the rotation shaft at a position facing the rotor,
    The stator of a rotating electrical machine according to any one of claims 1 to 10, wherein the conductive wire portion has a thickness in the radial direction smaller than a circumferential width of one phase in one magnetic pole.
12. The stator winding (51) has conductor portions (81, 82) arranged at predetermined positions in a circumferential direction of the rotation shaft at a position facing the rotor,
    In the stator,
    An inter-conductor member (57, 142) is provided between the conductor portions in the circumferential direction, and as the inter-conductor member, the circumferential width of the inter-conductor member in one magnetic pole is Wt, and the inter-conductor member is Magnetic material having a relationship of Wt × Bs ≦ Wm × Br, where Sm is the saturation magnetic flux density of Bs, W is the circumferential width of the magnet portion at one magnetic pole, and W is the residual magnetic flux density of the magnet portion. Or a configuration using a non-magnetic material,
    The stator of a rotating electrical machine according to any one of claims 1 to 11, wherein the conductor-to-conductor member is not provided between the conductors in the circumferential direction.

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