Winding excitation rotor and manufacturing method of winding excitation rotor

Abstract

A winding excitation rotor (60) is provided with: a rotor core (70) having a main pole section (72); and a field winding (80) configured by winding a plurality of layers of wire materials (90) around each of the main pole sections such that the wire materials (90) are arranged in the radial direction and the circumferential direction. A field winding wound around each of the main pole sections has linear sections (81a, 82a, 101a, 102a) extending in the axial direction along the radial side surfaces of the main pole sections, and transition sections (101b, 102b) connecting the ends of the linear sections to each other. The cross-section of the linear portion has a rectangular shape having a long side in the radial direction. The field winding is configured such that, among the linear portions arranged in the circumferential direction and the radial direction in each main pole portion, the dimension in the short-side direction of the cross-section of the linear portion on the inner side in the radial direction is smaller than the dimension in the short-side direction of the cross-section of the linear portion on the outer side in the radial direction.

Description

[0001] Cross-reference to related applications

[0002] This application is based on Japanese Patent Application No. 2023-028955 filed on February 27, 2023, and the contents thereof are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a winding excitation rotor and a method for manufacturing the winding excitation rotor. Background Art

[0004] As such a winding excitation rotor, there is known a rotor core having a main pole portion provided for each circumferentially arranged magnetic pole and protruding in the radial direction, and an excitation winding, wherein the rotor core has a main pole portion provided for each circumferentially arranged magnetic pole, and the excitation winding is constructed by winding a plurality of layers of conductive wire around each main pole portion in such a manner that the conductive wire is arranged in the radial and circumferential directions.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 2008-178211

[0008] The field winding wound around each main pole portion includes a straight portion extending in the axial direction along a radial side surface of the main pole portion and a transition portion connecting end portions of the straight portion.

[0009] The distance between circumferentially adjacent main poles decreases radially inward. Consequently, the radially innermost and circumferentially outermost straight line portion of the field winding wound on one circumferentially adjacent main pole can interfere with the radially innermost and circumferentially outermost straight line portion of the field winding wound on the other circumferentially adjacent main pole. To avoid this interference, reducing the number of turns of the field winding is an option. However, this increases the dead space between circumferentially adjacent main poles, raising concerns about a reduction in the field winding's slot fill factor. Summary of the Invention

[0010] The main object of the present disclosure is to provide a winding field rotor and a method for manufacturing the winding field rotor, which are capable of improving the slot filling factor of the field winding.

[0011] The present invention discloses a winding excitation rotor, which is applied to a winding excitation type rotating electrical machine and comprises:

[0012] a rotor core having a main pole portion provided for each of the circumferentially arranged magnetic poles and protruding in the radial direction; and

[0013] an excitation winding, wherein the excitation winding is formed by winding the conductive wire in multiple layers around each of the main pole portions in such a manner that the conductive wire is arranged in the radial and circumferential directions;

[0014] The field winding wound around each of the main pole portions includes:

[0015] a straight portion extending in the axial direction along a radial side surface of the main pole portion; and

[0016] A transition portion connects the ends of the straight portion to each other.

[0017] In the present disclosure, the cross section of the straight portion is in a rectangular shape with the radial direction as the long side.

[0018] The field winding is configured such that, in each main pole portion, among the straight portions arranged in the circumferential direction and the radial direction, the short-side dimension of the cross-section of the radially inner straight portion is smaller than the short-side dimension of the cross-section of the radially outer straight portion.

[0019] This prevents the radially inner straight portion of the field winding wound around one of the circumferentially adjacent main poles from interfering with the radially inner straight portion of the field winding wound around the other main pole, and increases the number of turns of the field winding 80 on the radially inner side of the main pole. Consequently, the dead space between the circumferentially adjacent main poles can be reduced, and the field winding slot fill factor can be increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above objects and other objects, features and advantages of the present disclosure will become more apparent through the following detailed description with reference to the accompanying drawings. The accompanying drawings are as follows:

[0021] Figure 1 is an overall structural diagram of a control system for a rotating electrical machine according to an embodiment.

[0022] Figure 2 This is a diagram showing the inverter and its surrounding structure.

[0023] Figure 3 is the cross-sectional view of the rotor,

[0024] Figure 4 is a diagram showing a resonant circuit provided by the rotor.

[0025] Figure 5 This is a three-dimensional diagram showing the structure of the coil body.

[0026] Figure 6 is a flow chart showing the manufacturing process of the rotor.

[0027] Figure 7 This is a three-dimensional diagram showing how the wire is wound around the base die.

[0028] Figure 8 This is a three-dimensional diagram showing how the wire is wound around the base die.

[0029] Figure 9 This is a perspective view showing the completed state of the wire winding.

[0030] Figure 10 This is a three-dimensional diagram showing how the side mold moves.

[0031] Figure 11 This is a three-dimensional diagram showing how the side mold, main movable mold, and auxiliary movable mold move.

[0032] Figure 12 This is a cross-sectional view showing the compression molding method of the wire rod.

[0033] Figure 13 This is a cross-sectional view showing the compression molding method of the wire rod.

[0034] Figure 14 This is a cross-sectional view showing the compression molding method of the wire rod.

[0035] Figure 15 2 is a cross-sectional view showing a compression molding method of a wire rod according to another embodiment.

[0036] Figure 16 2 is a cross-sectional view showing a compression molding method of a wire rod according to another embodiment.

[0037] Figure 17 2 is a cross-sectional view showing a compression molding method of a wire rod according to another embodiment.

[0038] Figure 18 2 is a cross-sectional view showing a compression molding method of a wire rod according to another embodiment.

[0039] Figure 19 This is a perspective view showing a method of winding a wire rod around a base die according to another embodiment.

[0040] Figure 20 2 is a cross-sectional view showing a compression molding method of a wire rod according to another embodiment.

[0041] Figure 21 2 is a cross-sectional view showing a compression molding method of a wire rod according to another embodiment.

[0042] Figure 22 is a perspective view showing the structure of a coil body according to another embodiment.

[0043] Figure 23 is a perspective view showing the structure of a coil body according to another embodiment.

[0044] Figure 24 is a cross-sectional view of a rotor according to another embodiment.

[0045] Figure 25 is a cross-sectional view of a rotor according to another embodiment.

[0046] Figure 26 It is a cross-sectional view showing a compression-molding method of a wire rod according to another embodiment. DETAILED DESCRIPTION

[0047] Various embodiments will be described with reference to the accompanying drawings. In various embodiments, functionally and / or structurally corresponding and / or related parts may be denoted by the same reference numerals or by different reference numerals above the hundredth place. For corresponding and / or related parts, reference can be made to the description of other embodiments.

[0048] Hereinafter, one embodiment of a winding field rotor according to the present disclosure will be described with reference to the drawings.

[0049] First, use Figure 1 A control system including a rotating electrical machine will be described. The control system includes a DC power supply 10, an inverter 20, a control unit 30, and a rotating electrical machine 40. The rotating electrical machine 40 is a winding-excited synchronous machine. In this embodiment, the control unit 30 controls the rotating electrical machine 40 so that it functions as an ISG (Integrated Starter Generator) or MG (Motor Generator), which is a motor-generator. For example, the rotating electrical machine 40, the inverter 20, and the control unit 30 may constitute a mechatronic drive device, or the rotating electrical machine 40, the inverter 20, and the control unit 30 may each be composed of separate components.

[0050] use Figure 1 The rotary electric machine 40 is briefly described. The rotary electric machine 40 includes a housing 41 and a stator 50 and a rotor 60 housed in the housing 41. The rotary electric machine 40 of this embodiment is an inner rotor type in which the rotor 60 is arranged radially inward of the stator 50.

[0051] The stator 50 includes a stator core 51 and stator windings 52 wound around the stator core 51. The stator core 51 is constructed from laminated steel plates formed of a soft magnetic material and includes an annular back yoke and a plurality of teeth protruding radially inward from the back yoke. The stator windings 52 are constructed, for example, from copper wire and include U-, V-, and W-phase windings 52U, 52V, and 52W, arranged with electrical angles offset by 120°.

[0052] The rotor 60 includes a rotor core 70 and a field winding 80. The rotor core 70 is formed of a soft magnetic material, for example, by laminating steel plates. The field winding 80 is formed by compression molding, for example. The field winding 80 can be formed of copper wire or aluminum wire.

[0053] The rotating shaft 32 is inserted through the center hole of the rotor core 70. The rotating shaft 32 is rotatably supported by the housing 41 via a bearing 42. The stator 50 and the rotor 60 are both arranged coaxially with the rotating shaft 32. In the following description, the direction in which the rotating shaft 32 extends is referred to as the axial direction, the direction radially extending from the center of the rotating shaft 32 is referred to as the radial direction, and the direction extending circumferentially around the rotating shaft 32 is referred to as the circumferential direction.

[0054] like Figure 2 As shown, the inverter 20 includes a series connection of U, V, and W-phase upper arm switches SUP, SVp, and SWp, and U, V, and W-phase lower arm switches SUn, SVn, and SWn. The first ends of the U, V, and W-phase windings 52U, 52V, and 52W are connected to the connection point between the U, V, and W-phase upper arm switches SUP, SVp, and the U, V, and W-phase lower arm switches SUn, SVn, and SWn. The second ends of the U, V, and W-phase windings 52U, 52V, and 52W are connected via a neutral point. That is, in this embodiment, the U, V, and W-phase windings 52U, 52V, and 52W are star-connected. In addition, in this embodiment, each switch SUP to SWn is an IGBT. Each switch SUP, SVp, SWp, SUn, SVn, and SWn is connected in antiparallel to a freewheeling diode.

[0055] The collectors of the U-, V-, and W-phase upper arm switches SUp, SVp, and SWp are connected to the positive terminal of DC power supply 10. The emitters of the U-, V-, and W-phase lower arm switches SUn, SVn, and SWn are connected to the negative terminal of DC power supply 10. Furthermore, a smoothing capacitor 11 is connected in parallel to DC power supply 10.

[0056] Next, use Figure 3 The rotor 60 will be described.

[0057] The rotor core 70 includes a cylindrical portion 71, which serves as a cylindrical yoke; a plurality of main pole portions 72, which project radially outward from the cylindrical portion 71; and flange portions 74, which extend radially from the tips of the main pole portions 72. In this embodiment, the main pole portions 72 are arranged at equal intervals in the circumferential direction.

[0058] The field winding 80 includes a first winding portion 81 and a second winding portion 82. In each main pole portion 72, the first winding portion 81 is wound radially outward, and the second winding portion 82 is wound radially inward relative to the first winding portion 81. In each main pole portion 72, the first winding portion 81 and the second winding portion 82 are wound in the same direction. Furthermore, the winding direction of each winding portion 81, 82 wound around one of the circumferentially adjacent main pole portions 72 is opposite to the winding direction of each winding portion 81, 82 wound around the other main pole portion. Therefore, the magnetization directions of circumferentially adjacent main pole portions 72 are opposite to each other.

[0059] Figure 4 The figure shows the circuit on the rotor 60 side, which includes windings 81 and 82 wound around the common main pole portion 72. A diode 83 and a capacitor 84 are provided on the rotor 60 as rectifying elements. The cathode of the diode 83 is connected to the first end of the first winding portion 81, and the second end of the first winding portion 81 is connected to the first end of the second winding portion 82. The second end of the second winding portion 82 is connected to the anode of the diode 83. The second winding portion 82 is connected in parallel with the capacitor 84. Alternatively, the anode of the diode 83 may be connected to the first end of the first winding portion 81, and the cathode of the diode 83 may be connected to the second end of the second winding portion 82.

[0060] In the present embodiment, a series resonant circuit is formed by the first winding portion 81 , the capacitor 84 , and the diode 83 , and a parallel resonant circuit is formed by the second winding portion 82 and the capacitor 84 .

[0061] return Figure 2 As described above, the control unit 30 generates drive signals for turning on and off the switches SUp to SWn that constitute the inverter 20. Specifically, the control unit 30 converts the DC power output from the DC power supply 10 into AC power, generates drive signals for turning on and off the switches SUp to SWn in each arm, which should be supplied to the U-, V-, and W-phase windings 52U, 52V, and 52W, and supplies the generated drive signals to the gates of the switches SUp to SWn in each arm.

[0062] The control unit 30 turns on and off the switches SUP to SWn so that a composite current of the fundamental current and harmonic current flows through each phase winding 52U, 52V, and 52W. The fundamental current primarily generates torque in the rotating electrical machine 40. The harmonic current primarily excites the field winding 80, causing a magnetic current to flow through the field winding 80. The phase currents flowing through the phase windings 52U, 52V, and 52W are staggered by 120 electrical degrees.

[0063] Furthermore, part or all of the functions of the control unit 30 may be implemented as hardware, such as one or more integrated circuits, etc. Alternatively, the functions of the control unit 30 may be implemented as software stored in a non-transitory physical storage medium and a computer executing the software.

[0064] Then use Figure 3 The field winding 80 will be described.

[0065] The wire rod that constitutes the field winding 80 is a rectangular wire with a rectangular cross-section (specifically, a long rectangle). The wire rod is flatly wound so as to be arranged in the radial and circumferential directions to form the field winding 80. The wire rod consists of a conductor portion and an insulating layer (e.g., an insulating film) that covers the conductor portion.

[0066] The field winding 80 includes a straight portion extending in the axial direction on the radial side surface of the main pole portion 72 and a transition portion connecting the ends of the straight portion and extending in the circumferential direction. Figure 3 In FIG. 8 , 81 a denotes a straight portion of the first winding portion 81 , and 82 a denotes a straight portion of the second winding portion 82 .

[0067] exist Figure 3 In the illustrated example, the straight portions 81a of the first winding portion 81 are arranged in two radial rows. Six straight portions 81a are arranged circumferentially in the first layer of the first winding portion 81, which is radially closest to the stator 50, and five straight portions 81a are arranged circumferentially in the second layer. The straight portions 82a of the second winding portion 82 are arranged in two radial rows. Five straight portions 82a are arranged circumferentially in the first layer of the second winding portion 82 (i.e., the third layer of the field winding 80), which is radially closest to the stator 50, and four straight portions 82a are arranged circumferentially in the second layer (i.e., the fourth layer of the field winding 80).

[0068] In the first and second winding sections 81 and 82, the longitudinal dimension of the cross-section of the straight portions 81a and 82a is denoted by KA, the transverse dimension of the cross-section of the straight portions 81a and 82a is denoted by KB, and the aspect ratio is denoted by KA / KB. In this embodiment, the first and second winding sections 81 and 82 are configured such that, among the straight portions 81a and 82a arranged circumferentially and radially in each main pole portion 72, the aspect ratio of the radially inner straight portion 82a is greater than that of the radially outer straight portion 81a. This configuration improves the slot fill factor of the field winding 80.

[0069] The aspect ratio of the straight portion 81a constituting the first winding portion 81 may be, for example, 1.8 to 10, 1.8 to 8, 1.9 to 6, or 2 to 5. Furthermore, the aspect ratio of the straight portion 82a constituting the second winding portion 82 may be, for example, 1.3 to 5 times, 1.5 to 5 times, 1.8 to 4 times, or 2 to 3 times the aspect ratio of the straight portion 81a constituting the first winding portion 81.

[0070] The center axis of the main pole portion 72 extending radially through the rotation center axis O of the rotating shaft 32 of the rotor 60 is referred to as the first axis B1. Furthermore, the axis extending radially through the circumferential center of the circumferentially adjacent first axis B1 and the rotation center axis O is referred to as the second axis B2. The first axis B1 corresponds to the d-axis, and the second axis B2 corresponds to the q-axis. According to the winding method of this embodiment, the circumferentially outermost straight portion of the field winding 80 can be brought closer to the second axis B2. This increases the proportion of space occupied by the field winding 80 in the space between circumferentially adjacent main pole portions 72, thereby increasing the slot fill rate of the field winding 80 in the rotor 60. Using a rectangular wire with a large cross-sectional area can reduce the resistance value of the field winding 80, reduce losses in the field winding 80, and improve the excitation magnetism of the field winding 80.

[0071] In addition, Figure 3 In the example shown, a gap exists between circumferentially adjacent excitation windings 80. However, the present invention is not limited to a structure having a gap, and for example, a structure in which the outer end portions of circumferentially adjacent excitation windings 80 abut against a sheet-like insulating member (e.g., insulating paper) provided along the second axis B2 may also be employed.

[0072] The field winding 80 has a plurality of coil bodies 100 formed by winding a rectangular wire in multiple layers in the radial direction for each magnetic pole (each main pole portion 72), and the field winding 80 is formed by connecting the coil bodies 100 of each magnetic pole in series in the circumferential direction. Figure 3 In the illustrated structure, the first winding portion 81 of each main pole portion 72 is formed by one coil body 100 , and the second winding portion 82 of each main pole portion 72 is formed by one coil body 100 .

[0073] Figure 5 (a) is a perspective view showing the basic structure of the coil body 100. Figure 5 In (a), direction A is radial, direction B is axial, and direction C is circumferential. Figure 5 In the structure of (a), the number of windings of the radially inner and outer layers is the same, but Figure 3 As shown, the number of windings in the radial direction inside and outside can also be different.

[0074] The coil body 100 is an air-core coil constructed as an α-wound coil, and the two layers of windings arranged in the radial direction are formed into one body. That is, the coil body 100 has an inner coil portion 101 and an outer coil portion 102, which are respectively radially inward (inner layer side) and radially outward (outer layer side) when installed on the main pole portion 72. In each coil portion 101, 102, the wire rod 90 is connected to each other on the inner circumference of the coil. The coil body 100 can also be said to be a unit coil with two radial layers as one unit. In addition, the inner coil portion 101 has a coil end 103 extending axially from the surrounding portion, and the outer coil portion 102 has a coil end 104 extending axially from the surrounding portion. The coil body 100 is installed on the main pole portion 72 by inserting the main pole portion 72 through the hollow portion. As described above, the coil body 100 has a straight portion and a transition portion. Specifically, the inner coil portion 101 includes a straight portion 101 a and a transition portion 101 b , and the outer coil portion 102 includes a straight portion 102 a and a transition portion 102 b .

[0075] In the field winding 80, the coil bodies 100 of the circumferentially adjacent magnetic poles are connected in series by joining the coil ends 103 and 104 of the coil bodies 100. Figure 5 (b) and (c) illustrate an example of its structure. Figure 5 (b) shows two coil bodies 100 having different coil end portions 103 and 104. In the following description, one of the two coil bodies 100 is referred to as "first coil body 100A," and the other as "second coil body 100B." Furthermore, the coil ends 103 and 104 in the first coil body 100A are referred to as "coil ends 103a and 104a," and the coil ends 103 and 104 in the second coil body 100B are referred to as "coil ends 103b and 104b."

[0076] like Figure 5 As shown in (b), in the first coil body 100A, the coil ends 103a and 104a of the inner coil portion 101 and the outer coil portion 102 are shaped like the coil end 104a of the outer coil portion 102. Figure 5 Specifically, the coil end 104a of the outer coil portion 102 is different from the coil end 104 shown in (a). Figure 5 The end position shown in (a) does not extend directly in the axial direction, but extends circumferentially along the upper surface of the surrounding part of the first coil body 100A, and bends axially at a position that is offset by one pole spacing in the circumferential direction, that is, at a position that is roughly horizontally arranged with the coil end 103a of the inner coil part 101.

[0077] In the second coil body 100B, the coil end portions 103b and 104b of the inner coil portion 101 and the outer coil portion 102 have the same shape as the coil end portion 103b of the inner coil portion 101. Figure 5 Specifically, the coil end 103b of the inner coil portion 101 is different from the coil end 103 shown in (a). Figure 5 The end portion shown in (a) does not extend directly in the axial direction, but extends circumferentially on the side opposite to the surrounding portion of the second coil body 100B, and bends in the axial direction at a position offset by one magnetic pole pitch in the circumferential direction.

[0078] In summary, the first coil body 100A and the second coil body 100B are formed as a coil body 100 ( Figure 5 Based on the coil body 100 shown in (a), there are two types of coil bodies 100 with different shapes of coil end portions 103 and 104.

[0079] Figure 5 (c) is a diagram showing a state where the coil bodies 100A and 100B arranged in the circumferential direction are connected in series. Figure 5 In (c), for convenience, the coil bodies 100A and 100B are arranged in a straight line rather than in an arc. In this case, the coil ends 103a and 103b of the coil bodies 100A and 100B are joined together on the radially inner side, and the coil ends 104a and 104b of the coil bodies 100A and 100B are joined together on the radially outer side. The coil ends 103 and 104 are joined together, for example, by welding.

[0080] Furthermore, in the actual structure, when the coil bodies 100A and 100B are arranged in an arc shape, the coil bodies 100A and 100B are not arranged in a straight line when viewed from above, but are arranged in a state of intersecting each other. Therefore, at least one of the mutually joined coil ends 103a and 103b can be raised axially on a line that intersects obliquely with respect to the extension direction. This allows the coil ends 103 to be appropriately surface-joined with each other. For example, the direction in which the surface joints of the coil ends 103 are joined can be set to be along a straight line extending from the rotation center point of the rotor 60. The same applies to the coil ends 104a and 104b.

[0081] Next, use Figure 6 A method for manufacturing the field winding 80 will be described. Hereinafter, the first winding portion 81 of the first winding portion 81 and the second winding portion 82 constituting the field winding 80 will be mainly described.

[0082] In step S10, the middle portion 90a of the wire rod 90 (specifically, a round wire) having a circular cross section is used as the winding start portion, and the first wire portion 91 of the wire rod 90, which is one end side relative to the winding start portion, is wound around the base die 200 in a first direction. On the other hand, the second wire portion 92 of the wire rod 90, which is the other end side relative to the winding start portion, is wound around the base die 200 in a second direction opposite to the first direction (see FIG. Figure 7 and Figure 8 The base die 200 is a die that constitutes a punching device and simulates the main pole portion 72. The lead wires 91 and 92 are wound around the base die 200 by a winding device.

[0083] In step S11, the central die 210 constituting the punching device is moved so as to be positioned between the first lead portion 91 and the second lead portion 92 (see FIG. Figure 9 The central mold 210 of this embodiment is divided into two parts in the vertical direction, and is composed of a first central mold 211 and a second central mold 212.

[0084] In step S12, in the state where the central mold 210 is arranged, the first wire portion 91 and the second wire portion 92 are further wound around the base mold 200 by the winding device. Figure 9 As shown, an α-shaped wound coil body 100 is manufactured. The portion of coil body 100 formed by first conductor portion 91 is inner coil portion 101 (equivalent to "first coil portion"), and the portion of coil body 100 formed by second conductor portion 92 is outer coil portion 102 (equivalent to "second coil portion"). One surface of central mold 210 abuts inner coil portion 101, and the other surface of central mold 210 abuts outer coil portion 102.

[0085] In step S13, the first side mold 221 is moved toward the central mold 210 (see Figure 10 ), the first side mold 221 is brought into contact with the opposite side of the abutment portion on the central mold 210 side of the inner coil portion 101. In addition, the second side mold 222 is moved toward the central mold 210, so that the second side mold 222 is brought into contact with the opposite side of the abutment portion on the central mold 210 side of the outer coil portion 102.

[0086] In step S14 (equivalent to the "pressing process"), the inner coil portion 101 is sandwiched between the central die 210 and the first side die 221. Figure 11As shown, by pressing the main movable mold 230 from the top to the side of the base mold 200 against the straight portion 101a constituting the inner coil portion 101, the cross section of the straight portion 101a constituting the inner coil portion 101 is compressed and formed into a rectangular shape. Figures 12 to 14 As shown in FIG. 1 , the straight portion 101a having a circular cross section is compressed and formed in stages. As the compression is formed, the straight portion 101a extends in a direction perpendicular to the compression direction of the straight portion 101a. Figure 13 As shown, the movement of the first side mold 221 can be allowed.

[0087] Furthermore, in step S14, with the outer coil portion 102 sandwiched between the central mold 210 and the second side mold 222, the main movable mold 230 is pressed against the straight portion 102a constituting the outer coil portion 102 from the top to the side of the base mold 200. Thus, similar to the inner coil portion 101, the cross-section of the straight portion 102a constituting the outer coil portion 102 is compression-formed into a rectangular shape. As the compression-forming proceeds, the straight portion 102a extends in a direction perpendicular to the compression direction of the straight portion 102a, thereby allowing movement of the first side mold 221.

[0088] By using the stamping process of the main movable die 230, as Figure 3 As shown, the straight portion 101a constituting the inner coil portion 101 and the straight portion 102a constituting the outer coil portion 102 have a rectangular cross section. The straight portion 101a constituting the inner coil portion 101 corresponds to Figure 3 The first winding portion 81 shown has five straight portions 81a arranged in the circumferential direction. The straight portion 102a constituting the outer coil portion 102 corresponds to Figure 3 The illustrated first winding portion 81 has six straight portions 81 a arranged in the circumferential direction.

[0089] In step S14, the inner coil portion 101 is sandwiched between the central mold 210 and the first side mold 221. Figure 11 As shown, the auxiliary movable mold 231 is pressed against the transition portion 101b constituting the inner coil portion 101 from the left-right direction toward one side of the base mold 200, thereby compressing the cross-section of the transition portion 101b constituting the inner coil portion 101 into a rectangular shape. Here, similarly to the straight portion 101a, the transition portion 101b having a circular cross-section is compression-formed in stages. As the compression forming proceeds, the transition portion 101b extends in a direction perpendicular to the compression direction of the transition portion 101b, thereby allowing movement of the first side mold 221.

[0090] Furthermore, in step S14, with the outer coil portion 102 sandwiched between the central mold 210 and the second side mold 222, the auxiliary movable mold 231 is pressed against the transition portion 102b constituting the outer coil portion 102 from the left-right direction toward one side of the base mold 200, thereby compression-molding the transition portion 102b constituting the outer coil portion 102 into a rectangular cross-section, similar to the inner coil portion 101. As the compression molding proceeds, the transition portion 102b extends in a direction perpendicular to the compression direction of the transition portion 102b, thereby allowing movement of the second side mold 222.

[0091] By the press process using the auxiliary movable die 231 , the transition portion 101 b constituting the inner coil portion 101 and the transition portion 102 b constituting the outer coil portion 102 have rectangular cross sections.

[0092] After step S14 , in step S15 , the compression-molded coil body 100 is removed from the base mold 200 .

[0093] The coil body 100 constituting the first winding portion 81 is manufactured through the process of steps S10 to S15 described above. Similarly, the coil body 100 constituting the second winding portion 82 is manufactured through the process of steps S10 to S15. In this case, in step S14, the inner coil portion 101 and the outer coil portion 102 are compression-formed in such a manner that the aspect ratio of the coil body 100 constituting the second winding portion 82 arranged radially inwardly of the main pole portion 72 (equivalent to the "inner coil body") is greater than the aspect ratio of the coil body 100 constituting the first winding portion 81 arranged radially outwardly of the main pole portion 72 (equivalent to the "outer coil body") (refer to Figure 3 ).

[0094] In the next step S16 , the coil body 100 constituting the first winding portion 81 and the coil body 100 constituting the second winding portion 82 are inserted into the main pole portion 72 .

[0095] In addition, the composition Figure 6 The central mold 210, the first side mold 221, the second side mold 222, the main movable mold 230, the auxiliary movable mold 231 and the winding device of the stamping forming device described in Figure 6 Each device required in the manufacturing process is controlled by a controller.

[0096] In the embodiment described above, the cross-sections of the straight portions 81a and 82a that comprise each winding portion 81 and 82 are rectangular in shape, with the radial direction being the long side. The aspect ratio of the straight portion 82a that comprises the second winding portion 82 is greater than the aspect ratio of the straight portion 81a that comprises the first winding portion 81. Consequently, in each main pole portion 72, among the straight portions arranged circumferentially and radially, the short-side dimension of the cross-section of the straight portion 82a of the second winding portion 82 is smaller than the short-side dimension of the cross-section of the straight portion 81a of the first winding portion 81. As a result, interference between the circumferentially outermost straight portion 82a of the second winding portion 82 wound around one of the circumferentially adjacent main pole portions 72 and the circumferentially outermost straight portion 82a of the second winding portion 82 wound around the other main pole portion can be avoided, and the number of turns of the excitation winding 80 on the radially inner side of the main pole portion 72 can be increased. As a result, the dead space between the circumferentially adjacent main pole portions 72 can be reduced, and the slot fill factor of the field winding 80 can be improved. This reduces the resistance of the field winding 80 and improves the excitation magnetic field of the field winding 80.

[0097] In addition, using the above aspect ratio setting, such as Figure 3 As shown, the number of circumferentially arranged straight portions (five) of the straight portions 82a constituting the second winding portion 82 that are radially closest to the first winding portion 81 can be made the same as the number of circumferentially arranged straight portions (five) of the straight portions 81a constituting the first winding portion 81 that are radially closest to the second winding portion 82. Alternatively, the number of circumferentially arranged straight portions of the straight portions 82a constituting the second winding portion 82 that are radially closest to the first winding portion 81 can be made greater than the number of circumferentially arranged straight portions of the straight portions 81a constituting the first winding portion 81 that are radially closest to the second winding portion 82.

[0098] <Other implementation methods>

[0099] Furthermore, the above-mentioned embodiment may be implemented with modifications as follows.

[0100] exist Figure 6 In the press process of step S14, the transition portions 101b and 102b may be compression-molded without using the auxiliary movable die 231. In this case, the cross-sections of the transition portions 101b and 102b are circular.

[0101] like Figure 15 and Figure 16 As shown, the straight portion 101a of the inner coil portion 101 and the straight portion 102a of the outer coil portion 102 may be simultaneously compression-molded by the main movable mold 230. Figure 15 and Figure 16 , for convenience, an example is shown in which five coil portions 101 and 102 are formed. Alternatively, three or more layers of straight portions may be formed simultaneously.

[0102] In addition, if Figure 17 As shown, by further winding the second wire portion 92, an additional straight portion 102c is arranged on the upper side of the straight portion 102a, as shown in FIG. Figure 18 As shown, the compression molding can also be performed by a movable mold 232 having an inclined surface 232a. Thus, a straight portion 102d having an inclined portion is formed. The straight portion having an inclined portion is Figure 3 By providing the field winding 80 with a straight portion having an inclined portion, the distance between the field windings 80 adjacent to each other in the circumferential direction can be shortened, and the slot fill rate of the field winding 80 can be further improved.

[0103] exist Figure 6 In the winding process of step S10, it is possible to use not one wire 90 but Figure 19 As shown in FIG. 2 , two wire rods 90 arranged in the radial direction are wound together on the base die 200. In this case, two air-core coils consisting of the first wire portion 91 and the second wire portion 92 are manufactured. After manufacturing the two air-core coils, Figure 6 In the stamping process of step S14, the main movable die 230 compresses and forms the portion of each air-core coil consisting of the first conductor portion 91 (inner coil portion 101) and the portion of each air-core coil consisting of the second conductor portion 92 (outer coil portion 102). Figure 20 and Figure 21 , an example of compression molding the straight portion 101a of the portion (inner coil portion 101) consisting of the first conductor portion 91 of each air-core coil is shown. Figure 22 Schematic diagram of the inner coil portion 101 and the outer coil portion 102 as two air-core coils is shown in FIG. Thereafter, in the inner coil portion 101, the top ends 91a of the two first wire portions 91 are joined to each other by welding or the like using a welding device, and in the outer coil portion 102, the top ends 92a of the two second wire portions 92 are joined to each other by welding or the like using a welding device, thereby manufacturing a parallel connection body of the two air-core coils (the inner coil portion 101 and the outer coil portion 102) consisting of the first wire portions 91 and the second wire portions 92.

[0104] If the aspect ratio is to be increased, it is necessary to increase the pressure from the main movable die 230 to the wire rod 90. In this case, there is a concern that the insulating film on the surface of the wire rod 90 may be damaged. Figure 19 As shown, two wire rods 90 arranged in the radial direction are used. When the aspect ratio of the two wire rods 90 after compression molding is made the same as that of one wire rod 90 after compression molding (see Figure 14When the aspect ratio of the two conductors 90 is the same (e.g., the aspect ratio of the two conductors 90 is the same), the compression amount of the two conductors 90 in the moving direction of the main movable mold 230 can be made smaller than the compression amount of the single conductor 90. As a result, the pressure required for compression molding can be reduced, and even in the case of forming windings requiring a larger aspect ratio, damage to the insulation coating can be reduced. In addition, according to Figures 19 to 21 In the embodiment shown, the insulating coating can be interposed between two conductive wires 90 (for example, the straight portions), and the eddy current can be reduced compared to the case of using a single conductive wire 90 .

[0105] In addition, after the inner coil portion 101 and the outer coil portion 102 as two air-core coils are manufactured by the above method, Figure 23 As shown, the top end portion 91a of the two first wire portions 91 of the inner coil portion 101, which is located on the side of the outer coil portion 102, and the top end portion 92a of the two second wire portions 92 of the outer coil portion 102, which is located on the side of the inner coil portion 101, can be joined by welding with a welding device, etc., thereby manufacturing a series connection body of the inner coil portion 101 and the outer coil portion 102.

[0106] Incidentally, the present invention is not limited to using two conductor wires 90; N conductor wires 90 (N is an integer greater than or equal to 3) arranged in a radial direction may be collectively wound around base mold 200. In this case, the top ends of the N first conductor wires 91 are joined together by welding, etc., and the top ends of the N second conductor wires 92 are joined together by welding, etc., thereby producing a parallel connection of N air-core coils composed of the first conductor wires 91 and the second conductor wires 92. With N conductor wires, a shaped winding with a larger aspect ratio can be produced.

[0107] like Figure 24 As shown, the main movable die 230 may be used to perform stamping and forming in such a manner that the aspect ratio of the straight portion 81a in each layer of the first winding portion 81 is different. In addition, the main movable die 230 may be used to perform stamping and forming in such a manner that the aspect ratio of the straight portion 82a in each layer of the second winding portion 82 is different. Figure 24 In the illustrated example, seven, six, six, and five straight sections are formed in order from the radially outer side in each winding section 81, 82. By adopting an α-winding structure, concentrated winding with two layers can be formed, and the aspect ratio of each winding section 81, 82 can be changed midway between layers.

[0108] like Figure 25 As shown in FIG. 1 , a synthetic resin layer 120 as a molded resin having electrical insulation properties may be formed at least at the contact portion of the main pole portion 72 in each winding portion 81 , 82 (coil body). Figure 25In the example shown, the synthetic resin layer 120 is formed over the entire circumference of each winding portion 81, 82. The thickness of the synthetic resin layer 120 may be, for example, the same as or smaller than the width of the straight portion 82a constituting the second winding portion 82. In addition, the process of forming the synthetic resin layer 120 may be, for example, set to Figure 6 between steps S15 and S16.

[0109] Generally, in the case of round wire, the contact area between the main pole portion 72 and the round wire is small, and the pressure applied to the insulation layer (insulation coating) of the round wire becomes large. In this case, a winding frame for winding the excitation winding 80 is required. In contrast, Figure 25 The straight portions 81a and 82a shown are rectangular lines, which provide a large contact area with the main pole portion 72. Therefore, the pressure applied to the insulation layer of the straight portions 81a and 82a is reduced, eliminating the need for a bobbin. Consequently, the slot fill factor of the field winding 80 can be increased.

[0110] exist Figure 6 In the stamping process of step S14, the round wire is compressed and formed. Figure 26 As shown, each straight portion 101a, 102a can have concave and convex surfaces on their contact surfaces. Even in this case, compression molding allows each straight portion 101a, 102a to be in close contact with each other while having concave and convex surfaces on their contact surfaces, thereby improving the slot fill rate of the excitation winding 80. Incidentally, in this case, the height dimension of the concave and convex portions of each straight portion 101a, 102a is, for example, 0.1 to 0.2 mm. In addition, the rounded portions (R angles) of the four corners of each straight portion 101a, 102a are, for example, 0.2 mm or less.

[0111] In each main pole portion 72 , three or more coil bodies formed by winding two layers of conductive wire in the radial direction may be provided.

[0112] The capacitor 84 constituting the resonant circuit may be connected in parallel with the first winding portion 81 instead of the second winding portion 82. In addition, the direction of the diode 83 may be such that the cathode and the anode are opposite to each other. Figure 4 Alternatively, the anode of the diode 83 may be connected to one end of the first winding portion 81 , and the cathode of the diode 83 may be connected to one end of the second winding portion 82 .

[0113] The rotating electrical machine is not limited to an inner rotor type rotating electrical machine, and may be an outer rotor type rotating electrical machine. In this case, the main pole portion protrudes radially inward from the rotor core.

[0114] The rotating electric machine is not limited to a star-connected rotating electric machine, and may be a delta-connected rotating electric machine.

[0115] The stator core may be one without teeth.

[0116] The structure for flowing the excitation current to the excitation winding is not limited to Figure 4 The circuit shown may also be configured to include brushes electrically connected to the field winding and a power supply electrically connected to the brushes. In this case, it is not necessary to apply a harmonic voltage to the stator winding to induce the field current.

[0117] The rotating electric machine is not limited to one used as an in-vehicle main machine, and may be, for example, an ISG (Integrated Starter Generator) used as a motor and generator.

[0118] The mobile body on which the control system is mounted is not limited to a vehicle, and may be, for example, an airplane or a ship. In addition, the control system is not limited to a system mounted on a mobile body, and may be a stationary system.

[0119] Although the present disclosure has been described with reference to an embodiment, it should be understood that the present disclosure is not limited to the embodiment or structure. The present disclosure also includes various modifications and variations within the scope of the equivalent. In addition, various combinations or methods, as well as other combinations or methods including only one element, more than one element, or less than one element, also fall within the scope or scope of the present disclosure.

Claims

1. A winding excitation rotor (60), applied to a winding excitation type rotating electrical machine (40), characterized in that: have: a rotor core (70) having a main pole portion (72) provided for each of the circumferentially arranged magnetic poles and protruding in the radial direction; as well as The excitation winding (80) is formed by winding the wire (90) in multiple layers around each of the main poles in a manner such that the wire is arranged in radial and circumferential directions. The field winding wound around each of the main pole portions includes: a straight portion (81a, 82a, 101a, 102a) extending in the axial direction along a radial side surface of the main pole portion; and transition portions (101b, 102b) connecting the ends of the straight portions to each other, The cross section of the straight portion is in a rectangular shape with the radial direction as the long side. The field winding is configured such that, in each main pole portion, among the straight portions arranged in the circumferential direction and the radial direction, the short-side dimension of the cross-section of the radially inner straight portion is smaller than the short-side dimension of the cross-section of the radially outer straight portion.

2. The winding excitation rotor according to claim 1, characterized in that: The excitation winding has a plurality of coil bodies (100) for each main pole portion, and the coil bodies are formed by winding the conductive wire in two layers in the radial direction. Each of the coil bodies is α-wound.

3. The winding excitation rotor according to claim 2, characterized in that: The coil body is constructed such that, of the two layers of the straight portions constituting the coil body, the short-side dimension of the cross section of the radially inner straight portion (82a) is smaller than the short-side dimension of the cross section of the radially outer straight portion (81a).

4. The winding excitation rotor according to claim 2 or 3, characterized in that: A synthetic resin layer (120) having electrical insulation properties is formed on at least the contact portion of the main pole portion in the coil body.

5. The winding excitation rotor according to claim 2 or 3, characterized in that: When the coil body (81) arranged on the radially outer side is regarded as the outer coil body and the coil body (82) arranged on the radially inner side is regarded as the inner coil body, The number of circumferential arrangements of the straight portions (82a) constituting the inner coil body that are radially closest to the outer coil body is the same as or greater than the number of circumferential arrangements of the straight portions (81a) constituting the outer coil body that are radially closest to the inner coil body.

6. The winding excitation rotor according to claim 1, characterized in that: The field winding has a plurality of coil bodies for each main pole portion, and the coil bodies are formed by winding the conductive wire in multiple layers in the radial direction. Each of the coil bodies is α-wound, In each of the coil bodies, multiple layers of the conductive wires are connected in parallel.

7. The winding excitation rotor according to claim 1, characterized in that: The field winding has a plurality of coil bodies for each main pole portion, and the coil bodies are formed by winding the conductive wire in multiple layers in the radial direction. Each of the coil bodies is α-wound, In each of the coil bodies, multiple layers of the conductive wires are connected in series.

8. A method for manufacturing a winding excitation rotor (60), wherein the winding excitation rotor is applied to a winding excitation type rotating electrical machine (40), characterized in that: The winding excitation rotor comprises: a rotor core (70) having a main pole portion (72) provided for each magnetic pole arranged in the circumferential direction and protruding in the radial direction; as well as The excitation winding (80) is formed by winding the wire (90) in multiple layers around each of the main poles in a manner such that the wire is arranged in radial and circumferential directions. The field winding wound around each of the main pole portions includes: a straight portion (81a, 82a, 101a, 102a) extending in the axial direction along a radial side surface of the main pole portion; and transition portions (101b, 102b) connecting the ends of the straight portions to each other, The cross section of the straight portion is in a rectangular shape with the radial direction as the long side. The excitation winding has a plurality of coil bodies (100) for each main pole portion, and the coil bodies are formed by winding the conductive wire in multiple layers in the radial direction. The manufacturing method comprises: The process of manufacturing the coil body comprises taking the middle portion (90a) of a conductor wire (90) having a circular cross section as a winding starting portion, winding a first conductor wire portion (91) in a first direction around a base mold (200), and winding a second conductor wire portion (92) in a second direction opposite to the first direction around the base mold to manufacture the α-wound coil body, wherein the base mold is a mold simulating the main pole portion, the first conductor wire portion being a portion of the conductor wire at one end relative to the winding starting portion, and the second conductor wire portion being a portion of the conductor wire at the other end relative to the winding starting portion; as well as The stamping process is to make the first coil portion (101) formed by the first wire portion in the coil body and the second coil portion (102) formed by the second wire portion in the coil body abut against the central mold (210) arranged between the first coil portion and the second coil portion, and make the first coil portion abut against the first side mold (221) arranged on the opposite side of the central mold side of the first coil portion, and make the second coil portion abut against the second side mold (222) arranged on the opposite side of the central mold side of the second coil portion. In this state, by pressing the main movable mold (230) toward one side of the base mold against the straight portion (101a) forming the first coil portion, the cross section of the straight portion forming the first coil portion is compressed and formed into a rectangular shape. By pressing the main movable mold toward one side of the base mold against the straight portion (102a) forming the second coil portion, the cross section of the straight portion forming the second coil portion is compressed and formed into a rectangular shape. In the stamping step, the straight portions constituting the first coil portion and the second coil portion are compression-molded so as to form a cross section having long sides in directions perpendicular to the extending direction and the compression direction of the straight portions, respectively. In the stamping process, the outer coil body and the inner coil body are compression-formed in such a manner that the aspect ratio of the straight portion (82a) constituting the inner coil body (82) is greater than the aspect ratio of the straight portion (81a) constituting the outer coil body (81). The outer coil body is the coil body arranged on the radial outside, and the inner coil body is the coil body arranged on the radial inside compared to the outer coil body.

9. The method for manufacturing a winding excitation rotor according to claim 8, characterized in that: In the stamping process, the coil body is compression-formed in such a manner that the short side dimension of the cross section of the straight line portion arranged on the radially outer side of the two layers constituting the coil body is different from the short side dimension of the cross section of the straight line portion arranged on the radially inner side.

10. The method for manufacturing a winding excitation rotor according to claim 8 or 9, characterized in that: In the stamping process, the auxiliary movable die (231) is pressed against the transition portion (101b) constituting the first coil portion toward one side of the base die, thereby compressing and forming the cross section of the transition portion constituting the first coil portion into a rectangular shape; and the auxiliary movable die is pressed against the transition portion (102b) constituting the second coil portion toward one side of the base die, thereby compressing and forming the cross section of the transition portion constituting the second coil portion into a rectangular shape. In the pressing step, compression molding is performed so that the aspect ratio of the straight portion and the aspect ratio of the transition portion are different.

11. The method for manufacturing a winding excitation rotor according to claim 8 or 9, characterized in that: In the coil body compression-molded by the press step, the linear portions arranged in the circumferential direction are in close contact with each other in a state where their contact surfaces have projections and depressions.

Images