Rotating electrical machine and method for manufacturing stator in rotating electrical machine

Abstract

A stator coil of a rotating electric machine is formed by a concentric winding method. A stator coil is configured by inserting and connecting hairpin-shaped coil pieces (10, 11, 20, 21, 30, 31) formed from flat wires from one side and the other side in the axial direction. The length of the linear part of the coil piece is half of the axial length of the stator core, a convex shape or a concave shape is formed at the two leg end parts, and the convex part and the concave part are embedded. The coil is composed of three kinds of coil pieces: central coil pieces (10, 11) that connect the slots in the circumferential direction in the vicinity of the radial center of the slots; inner coil pieces (20, 21) that are connected in the circumferential direction so that coil end portions are biased inward in the radial direction than the radial positions of the slots; and outer coil pieces (30, 31) that are connected in the circumferential direction so as to be biased outward in the radial direction. Concentric coil portions formed by connected central coil pieces (10, 11), coil pieces (20, 31), and coil pieces (30, 21) are made to have the same length, so that the resistance values are made to be consistent, and the assemblability is improved.

Description

Technical Field

[0001] This invention relates to a rotary electric motor having a stator structure, a method for manufacturing the stator of the rotary electric motor, and a control system for the rotary electric motor. The stator structure is a radially spaced stator coil of the rotary electric motor formed by concentrically winding coils with different end shapes in each phase, which enables the resistance value to be the same in each phase. Background Technology

[0002] As power sources for industrial machinery and automobiles, rotary motors (electric motors) require improved efficiency. To increase efficiency, losses must be reduced. Generally, design methods focus on minimizing the two main loss factors: coil copper losses and core iron losses. When the required output characteristics (speed and torque) of the rotary motor are determined, mechanical losses are the sole determinant; therefore, minimizing iron and copper losses is crucial. Iron losses can be reduced by using soft magnetic materials. In typical rotary motors, electromagnetic steel plates are used in the core, with loss levels varying depending on the plate's thickness and Si content. Soft magnetic materials include high-performance materials with higher permeability and lower iron losses compared to electromagnetic steel plates, such as iron-based amorphous metals, FINEMET (iron-based nanocrystalline soft magnetic alloys), and nanocrystalline materials promising high magnetic flux density. However, these materials are extremely thin (0.025 mm) and have a Vickers hardness of 900, more than five times that of electromagnetic steel plates. This presents significant technical challenges in cost-effectively manufacturing rotary motors, thus limiting their application in this area.

[0003] Copper losses are primarily determined by the relationship between the coil's resistance and the current. Therefore, countermeasures include reducing coil resistance through cooling and reducing the current by suppressing the decrease in the magnet's residual magnetic flux density. Furthermore, recent designs in automotive drive motors, for example, have increased the ratio of the conductor's cross-sectional area to the stator slot (occupancy rate) to reduce resistance to the theoretical limit. However, using coils with flat wires that can increase the slot occupancy rate results in a complex winding (wiring) structure at the coil ends extending outwards from both ends of the slot. Connecting these conductors using methods such as welding leads to problems such as increased coil end volume (wire length) and a slight increase in resistance.

[0004] Patent Document 1 discloses a technique in which a two-pronged hairpin-shaped conductor segment is inserted into the stator coil of an electric motor, and the coil ends on the inserted side and the opposite side are bent into shapes. This is then welded to the bent conductor of another hairpin-shaped coil arranged circumferentially to form a ring-shaped coil. This method can improve the slot occupancy rate, but during manufacturing, it requires bending a thick, stiff, flat conductor, which can lead to stress on the stator core, damage to the slot insulation, or residual stress from bending at the connection point. This makes it difficult to ensure the reliability of the welded joint, and there is room for improvement in the manufacturing method. Furthermore, sufficient space must be ensured around the welded portion to perform the weld, resulting in the coil ends becoming larger on the welded side.

[0005] Among the methods attempting to improve these problems, the technology of Patent Document 2 is known. Patent Document 2 discloses a method for mechanically and firmly engaging the coil by using the shape of the coil's front end as a press-in tolerance. Furthermore, Patent Document 2 uses a resin winding frame, and by applying stress, engages the concave and convex front ends while reliably ensuring the coil's insertion area, thus achieving a highly reliable connection.

[0006] In the stator structures using flat wires shown in Patent Documents 1 and 2, a winding structure called wave-wound is employed. This is because the coil shapes are identical circumferentially, allowing for easy forming, insertion, twisting, and welding of hairpin-shaped coils. The wave-wound structure connects all coils circumferentially, so the number of coils per phase is equal to the number of slots per pole per phase. This results in a drawback: increasing the number of slots is required to increase the number of parallel coils, leading to low design freedom. Regarding design freedom, wave-wound requires an even number of turns per slot. With two slots per pole per phase, the two coils constituting System 1 and System 2 are alternately and evenly arranged in the same slot, increasing magnetic interference between the two coils. This magnetic interference can cause mutual interference of induced electromotive forces and disruption of the current waveform due to deviations in the timing of current application, especially when independently controlling the drive of the two coils.

[0007] To solve the aforementioned technical problems, a concentrically wound coil structure is considered. In the manufacture of a general rotary motor, multiple thin round wires are bundled together and wound to form a coil. This coil is then inserted into a stator slot using a device called an insertion machine. This method is used to create a concentrically wound stator. Patent document 3 shows a method for assembling a coil, pre-shaped and wound simultaneously, onto a stator core.

[0008] Existing technical documents

[0009] Patent documents

[0010] Patent Document 1: Japanese Patent Application Publication No. 2011-239651

[0011] Patent Document 2: International Publication No. 2020 / 017133

[0012] Patent Document 3: Japanese Patent Application Publication No. 2011-160572 Summary of the Invention

[0013] The technical problem that the invention aims to solve

[0014] In the manufacturing method of the technology shown in Patent Document 3, the coil is assembled in the axial direction or in the direction of the inner diameter of the semi-enclosed groove with a flange shape at the front end of the tooth, towards the outer periphery. Therefore, there is a problem that the proportion of the conductor cross-section in the cross-sectional area of ​​the groove, i.e., the occupancy rate, cannot be increased. In addition, because the shape of the coil end is different in each phase depending on the insertion order, it is difficult to manufacture the coil resistance and inductance values ​​consistently.

[0015] This invention was made in view of the above-mentioned problems, and its object is to improve the occupancy of the slots by combining flat wire hairpin-shaped conductors (coil sheets) in the concentrically wound stator of a rotating electric machine, and to make the coil end shapes of each phase coils into shapes that do not interfere with each other. Furthermore, it achieves a stator coil structure in which the coil lengths of each layer of the coil are the same, thus enabling the coil resistance and coil inductance to be the same. Moreover, it provides a rotating electric machine with improved stator coil assemblability.

[0016] Technical means for solving technical problems

[0017] The features of the present invention used to solve the above-mentioned technical problems are, for example, as described below.

[0018] According to one feature of the invention, the stator coil of a radially spaced rotary electric motor is shaped as a hairpin-shaped or U-shaped coil sheet made of flat wire, which is used to connect the slots for achieving the concentric winding structure. The length of the straight portion (straight part) of the coil sheet is approximately half the axial length of the stator core, and convex or concave shapes are formed at the two ends of the coil sheet, which can be respectively fitted. The coil end shapes of each phase of the coil sheet used to form the concentric winding are different for each phase, and the following three types of coil sheets are prepared: a coil sheet (central coil sheet) that connects the slots in the circumferential direction at the same position (insertion hole) or offset by one insertion hole; a coil sheet (inner coil sheet) that connects the slots in the circumferential direction with the coil end portion offset radially inward relative to the radial position of the slot; and a coil sheet (outer coil sheet) that connects the slots in the circumferential direction with the coil end portion offset outward relative to the radial position of the slot. At this point, regarding the coil's circumference, compared to a coil connected radially inward, a coil connected radially outward has a longer end length on the outside, resulting in a longer coil circumference and increased resistance. To balance the resistance, the coil on one axial side has its ends positioned on the inside, and the coil on the other axial side has its ends positioned on the outside, and these two are connected. This eliminates the difference in coil circumference caused by the inner and outer coil pieces, allowing for a more balanced coil resistance. The central coil, connected circumferentially near the radial center within the slot, is designed to have the same circumference as the coil formed by connecting the inner and outer coil pieces, resulting in consistent resistance. Therefore, even with concentric winding using flat conductors, uniform coil resistance and inductance can be achieved.

[0019] According to other features of the invention, the coil sheet is formed from a flat wire and has two straight portions and a coil end, wherein the two straight portions are portions housed in slots spaced apart in the circumferential direction, and the coil end is formed to extend outward from the straight portions in the direction of rotation axis, connecting the two straight portions. The coil end is formed by two extensions extending outward from the straight portions of the coil sheet in the direction of rotation axis, and a connecting portion connecting the ends of the extensions in the circumferential direction. After the stator coil is formed by wiring, the connecting portions of the central coil sheet are arranged in a radially arranged manner. By setting an angle such that the extensions of the inner coil sheet bend radially inward, the connecting portions of the inner coil sheet are arranged to be stacked in the direction of rotation axis in a manner that is radially inward of the stacked portion of the central coil sheet. By setting an angle such that the extensions of the outer coil sheet bend radially outward, the connecting portions of the outer coil sheet are arranged to be stacked in the direction of rotation axis in a manner that is radially outward of the stacked portion of the connecting portion of the central coil sheet. The angle of the inner coil plate's extension bending inward relative to the straight portion is greater than 0 degrees and less than 45 degrees, and the angle of the outer coil plate's extension bending outward relative to the straight portion is also greater than 0 degrees and less than 45 degrees. With such shapes for the inner and outer coil plates, when inserting the coil plates into the slots of the stator core from both sides in the direction of the rotation axis, the central coil plate, inner coil plate, and outer coil plate can be sequentially inserted and assembled one by one in the direction of the rotation axis.

[0020] According to another feature of the invention, the stator core comprises a back core and a plurality of toothed cores combined with the back core, the toothed cores being made of a low-loss soft magnetic material. Furthermore, in the slots between adjacent toothed cores, resin winding frames are respectively arranged to radially accommodate a plurality of flat wires. Additionally, to improve the assemblability of the coils, the stator core can be formed into a segmented shape in the direction of the rotation axis.

[0021] Invention Effects

[0022] By employing the aforementioned coil structure, concentrically wound coils with high conductor area ratio and low interphase coil resistance deviation can be constructed. This allows for the design of motors and systems utilizing the characteristics of the concentrically wound coil structure. Furthermore, because the number of coils can be independent of the number of slots per pole and phase, the flexibility in series and parallel circuits is high, easily accommodating design changes for different voltage specifications and frequencies (speed, torque). Specifically, with concentric winding, the number of turns in each slot can be designed to be odd, while with wave winding, the number of turns in each slot cannot be odd, thus increasing the design flexibility to accommodate these specification changes. Moreover, because the coils are independent structures within the system, magnetic interference is reduced, thus reducing constraints on the number of drive circuits used. Furthermore, during the stator coil concave-convex fitting assembly, by appropriately controlling the coil insertion sequence, coil connections can be performed simultaneously with insertion, significantly improving stator assemblability. Attached Figure Description

[0023] Figure 1A This is a perspective view showing the coil shape (1 pole, 3 phases) of a concentrically wound flat conductor in the stator of a radially gap type rotary motor 1 according to an embodiment of the present invention.

[0024] Figure 1B From Figure 1A The projection diagram of the leader line when viewed from one side of the axis of rotation.

[0025] Figure 1C From Figure 1A The projection of the opposite side when viewed along the direction of arrow 70 on the other side of the axis of rotation.

[0026] Figure 2A This is a three-dimensional view of stator core 3 in Figure 1.

[0027] Figure 2B This is the axial projection of the stator core 3 in Figure 1 (before the resin winding frame 65 is installed).

[0028] Figure 2C This is a three-dimensional view of the 65-unit winding frame when viewed from one side.

[0029] Figure 2D This is a three-dimensional view of the winding frame 65 unit viewed from the other side.

[0030] Figure 2E This is the axial projection of the stator core 3 in Figure 1 (after the winding frame 65 is installed).

[0031] Figure 3A This is a partial projection view when viewed from the opposite side 2b of the stator 2 shown in Figure 1.

[0032] Figure 3B From Figure 3A A three-dimensional image viewed from the inside.

[0033] Figure 3C yes Figure 3B A three-dimensional view of the central coil piece 11 shown.

[0034] Figure 3D yes Figure 3B A three-dimensional view of the inner coil piece 21 shown.

[0035] Figure 3E yes Figure 3B A three-dimensional view of the outer coil piece 31 shown.

[0036] Figure 4A This is a partial view taken from the lead-out side 2a of stator 2 shown in Figure 1.

[0037] Figure 4B From Figure 4A A three-dimensional view of the inside of stator 2 as shown.

[0038] Figure 4C yes Figure 4B A three-dimensional view of the central coil plate 10 shown.

[0039] Figure 4D yes Figure 4B A three-dimensional view of the inner coil sheet 20 shown.

[0040] Figure 4E yes Figure 4B A three-dimensional view of the outer coil plate 30 shown.

[0041] Figure 4F yes Figure 4B The three-dimensional view of lead coil piece 41 (lead coil pieces 42-46 are also the same) is shown.

[0042] Figure 5A This is a perspective view showing the stator 2 as a whole after the coil of the rotary motor 1 in this embodiment is formed.

[0043] Figure 5B yes Figure 5A The projection diagram of the lead-out side 2a of stator 2.

[0044] Figure 5C yes Figure 5A A three-dimensional view of the stator 2 on the opposite side 2b (showing the rotation axis reversed).

[0045] Figure 6A This is a diagram showing the stator 202 of the present example, and a perspective view showing the structure of one phase of the stator 202 using a waveform wound coil structure with flat wire.

[0046] Figure 6B This is a circuit diagram showing the two parallel delta connection method of stator 202.

[0047] Figure 6C This is a connection diagram showing stator 202.

[0048] Figure 7A This is a perspective view of the structure of one phase of a stator 202A, another existing example, which uses a wave-wound structure of flat wire.

[0049] Figure 7B This is a circuit diagram showing the two-series delta connection method of stator 202A.

[0050] Figure 7C This is the connection diagram for stator 202A.

[0051] Figure 8A This is a perspective view showing the structure of one phase of the stator 2 of the rotary motor 1 in this embodiment, which uses a concentric winding structure of flat wires.

[0052] Figure 8B It means Figure 8A The circuit diagram of the two parallel delta connection method of stator 2.

[0053] Figure 8C yes Figure 8A Connection diagram of stator 2.

[0054] Figure 9A This is a perspective view showing the structure of one phase of the stator 2 of the rotary motor 1 in this embodiment, which uses a concentric winding structure of flat wires.

[0055] Figure 9B It means Figure 9A The circuit diagram of the two-series delta connection method of stator 2.

[0056] Figure 9C yes Figure 9A Connection diagram of stator 2.

[0057] Figure 10A This is a circuit diagram showing the eight-parallel delta connection method of one phase of the stator of the rotary motor 1 using a concentric winding structure of flat wires in this embodiment.

[0058] Figure 10B express Figure 10A Connection diagram of stator 2.

[0059] Figure 11 This is a circuit diagram of a control system that uses two inverter devices to drive a rotary motor 1 with a concentrically wound stator 2 according to an embodiment of the present invention.

[0060] Figure 12This is a diagram of a coil slot configuration model of a stator using a waveform winding structure with flat wires, as an existing example.

[0061] Figure 13A It means Figure 12 A diagram of the linkage flux of the coil slot configuration model.

[0062] Figure 13B It means to use Figure 13A The graph shows the results of the crosslinked magnetic flux calculation obtained from the magnetic field analysis of the model.

[0063] Figure 14 This is a diagram showing the coil slot configuration model of the stator 2 using a concentric winding structure with flat wires in this embodiment.

[0064] Figure 15A It means Figure 14 The diagram shows the linkage flux of stator 2.

[0065] Figure 15B It means to use Figure 15A The graph shows the results of the crosslinked magnetic flux calculation obtained from the magnetic field analysis of the model.

[0066] Figure 16A This diagram shows the sequence of assembling the concentrically wound stator in this embodiment, and is a projection view of the insertion assembly side (lead-out side) of the stator 2 in step 1.

[0067] Figure 16B yes Figure 16A A three-dimensional view of the stator 2 in its state.

[0068] Figure 16C yes Figure 16A Projection view of the stator 2 insertion assembly side (lead-out side) in subsequent process 2.

[0069] Figure 16D yes Figure 16C A three-dimensional view of the stator 2 in its state.

[0070] Figure 16E yes Figure 16C The projection view of the stator 2 insertion assembly side (lead-out side) in the subsequent process 3.

[0071] Figure 16F yes Figure 16E A three-dimensional view of the stator 2 in its state.

[0072] Figure 16G yes Figure 16E The projection view of the stator 2 insertion assembly side (lead-out side) in the subsequent process 4.

[0073] Figure 16H yes Figure 16G A three-dimensional view of the stator 2 in its state.

[0074] Figure 17 This is a three-dimensional cross-sectional view showing an air compressor 100 driven by a rotary motor according to the present invention. Detailed Implementation

[0075] Hereinafter, embodiments of the rotary motor 1 of the present invention will be described using the accompanying drawings and other references. The following description illustrates specific examples of the content of the present invention, but the present invention is not limited to these descriptions. Those skilled in the art can make various changes and modifications within the scope of the technical concept disclosed in this specification. Furthermore, in all the drawings used to illustrate the present invention, parts having the same function are sometimes labeled with the same reference numerals, and repeated descriptions are omitted.

[0076] The rotary motor 1 in this embodiment is used to drive various devices. Figure 17 As an example, a screw-type air compressor 100 driven by a rotary motor 1 is shown. The air compressor 100 includes a rotary motor 1 that supplies rotational power, and an air end 101 that generates compressed air using the rotational force of the rotary motor 1. The rotary motor 1 is referred to as an embedded (built-in) magnet synchronous motor, and a rotor 6 and a stator 2 are housed within a housing 4. The housing 4 consists of a cylindrical main body 4a with openings on the front and rear sides, an end bracket (end cover) 4b mounted on the front side of the front opening of the main body 4a, and a rear end bracket 4c mounted on the rear opening of the main body 4a. A through hole is formed in the front end bracket 4b, and one end (one-end side) of the rotating shaft 5 that fixes the rotor 6 protrudes from the inside of the housing 4 to the front side of the exterior. A stator core 3 and stator coils 9 wound on the stator core 3 are formed in the stator 2. Figure 17 The figure schematically illustrates the shape of the end core portion of the stator coil 9, the detailed shape of which is shown in Figures 1 to 5 below.

[0077] The M rotor (male rotor) 120 of the compression mechanism 101 is connected to the rotating shaft 5 of the rotary motor 1 via a connecting mechanism (e.g., spline, coupling, gear, etc.), supplying rotational power from the rotary motor 1 to the first shaft 105 of the compression mechanism 101. Here, the rotating shaft 5 is directly connected to the first shaft 105, and its axis of rotation is Ax. A first bevel gear 110 is provided at the front end of the first shaft 105. The bevel gear 110 engages with an adjacent second bevel gear 130, causing the second bevel gear 130 to rotate at the same speed in the opposite direction as the first bevel gear 110. Because the second bevel gear 130 is located at the front end of the second shaft 135, the F rotor (female rotor) 140 fixed on the second shaft 135 rotates at the same speed in the opposite direction as the M rotor 120 fixed on the first shaft 105 due to the rotation of the second bevel gear 130.

[0078] Rotor M 120 and rotor F 140 rotate due to the rotation of the rotary motor 1, drawing in air through the intake port (not shown in the figure) of rotor M 120. As rotors M 120 and F 140 rotate further, the meshing of the teeth of each rotor disengages, filling the toothed space with air. As rotors M 120 and F 140 continue to rotate, the air intake is completed when it is blocked by the wall of housing 102. The air enclosed between the toothed space and the housing is compressed due to the meshing of rotors 120 and 140. Thus, as rotors 120 and 140 rotate, the air moves axially upwards and is further compressed between the toothed space 145 and housing 102, reaching the discharge port (not shown in the figure) and reaching the specified pressure. The compressed air is then discharged from the discharge port formed by the opening in housing 102.

[0079] Figure 1A This is a partial perspective view of the stator 2 of a rotary motor 1 according to an embodiment of the present invention. The rotary motor 1 of this embodiment is of the radial clearance type, and the coil of the stator 2 uses a so-called flat wire (hereinafter referred to as "flat wire") with a square cross-section orthogonal to the length direction. The stator coil 9 is formed by concentrically winding the flat wire. Figure 1A The middle part shows the coil shape of the 1-pole 3-phase stator coil 9.

[0080] The stator 2 has a total of 48 slots and 8 rotor poles. The coil pieces 10, 11, 20, 21, 30, 31, and 41-46 arranged in each slot are flat wires with a rectangular cross-section. Here, the stator 2 is configured in a shape divided into two parts along the rotation axis Ax: a lead-out side 2a and a lead-out opposite side 2b. On the lead-out side 2a of the stator coil 9, multiple coil pieces (10, 20, 30) are used to connect the slots, and multiple lead-out coil pieces 41-46 are used for wiring (connection) of the stator coil 9. On the lead-out opposite side 2b, multiple coil pieces (11, 21, 31) are used to connect the slots of the stator core 3. A coil (referred to as a U-phase coil) is formed by combining coil pieces (10, 20, 30) that connect the stator core 3 on the circumferential direction of the slot to the slot of the stator core 3 on the opposite side 2b at the same diameter position as the radial position of the slot 3c.

[0081] Used here Figures 2A-2E The detailed shape of stator core 3 is described. Figure 2A This is a three-dimensional view of the stator core 3 unit on the lead-out side 2a, showing the state where the winding frame 65 is installed but the stator coil 9 is not wound. Figure 2B From Figure 2A A magnified view of a portion of the structure when viewed from one side (lead-out side) along the axis of rotation (without the winding frame 65). For example... Figure 2A, Figure 2B As shown, the stator core 3 has a back core 3a formed on its outer periphery, and a tooth core 3b, formed by cutting amorphous metal foil strips into trapezoidal shapes and stacking them, is disposed in the tooth portion, thereby forming a total of 48 slots 3c in the circumferential direction. Because the frequency of the supplied voltage in the high-speed rotating motor 1 is high and the iron loss of the tooth portion is large, it is preferable to use a low-loss soft magnetic material. In this embodiment, the tooth portion is made of a different material than the material (electromagnetic steel plate) of the back core 3a portion. Alternatively, the tooth portion can be made of FINEMET, a nanocrystalline alloy material, or a highly saturated magnetized nanocrystalline alloy, instead of an amorphous material. Furthermore, when the tooth portion is made of the same material as the back core 3a using an electromagnetic steel plate, using a low-iron-loss material such as a thin steel plate containing 6.5% Si can be considered a method to improve the characteristics.

[0082] like Figure 2B As shown, in the stator core 3, a trapezoidal tooth core 3b with a cross-section orthogonal to the rotation axis is assembled, and a back core 3a is constructed using an electromagnetic steel plate to hold the tooth core 3b. The magnetic flux density on the back of the core is relatively low compared to the tooth portion, and the influence of higher harmonics is also smaller, so a material with relatively low loss can be used. In this structure, because it is difficult to stamp amorphous materials into complex shapes, the cross-sectional shape, which can be formed simply by cutting, is trapezoidal; the shape of the back core 3a is designed based on this. An insulating resin winding frame 65 is mounted to match the shape of this assembled core. Figure 2C This is a three-dimensional view taken from the inner circumference of the winding frame 65. Figure 2D This is a three-dimensional view taken from the outer periphery of the winding frame 65.

[0083] The winding frame 65 is formed with a length approximately equal to half the overall length of the stator core 3 along its rotation axis, i.e., the same length as the lead-out side 3a and the opposite lead-out side 3b of the stator core 3 (strictly speaking, the winding frame 65 is lengthened by the flange portions 67 and 68), and a width equal to the width of the slot 3c when viewed circumferentially. On the inner side of the winding frame 65, a plurality of m (m=4 here) insertion holes 66a to 66d are formed from the radially inner side to the outer side, for inserting flat conductors in a direction parallel to the rotation axis. Separating walls are provided at the boundary portions of the insertion holes 66a to 66d, creating a structure that reliably insulates each coil leaf individually. Flange portions 67 and 68 are provided at the axial ends of the winding frame 65, functioning to be held axially on the end faces of the toothed core 3b. Claw portions 67a and 68a, with claw-like protrusions in the outline, are formed on the inner circumferential sides of flange portions 67 and 68, respectively, for assembling the winding frame 65 by inserting it from the radially inner side to the outer side of the stator core 3. At this time, the claw portions 67a and 68a engage with the continuous recesses 3d formed on the inner circumferential side of the back core 3a in the direction of the rotation axis. With all the winding frames 65 installed in the slots 3c of the stator core 3, this structure restricts the tooth core 3b not only in the circumferential direction but also in the axial direction. Figure 2E It means from Figure 2B The diagram shows the state in which the winding frame 65 is installed.

[0084] Returning to Figure 1, the inner coil piece 20 and the outer coil piece 31 are combined to form a concentrically wound coil (hereafter referred to as a V-phase coil). The inner coil piece 20 is shaped to connect the slots between the slots 3c of the stator 2 on the lead-out side 2a by placing the coil ends at a position radially inward from the conductor entering the slot. The outer coil piece 31 is shaped to connect the slots between the stator 2 on the opposite lead-out side 2b at a position radially outward from the conductor's radial position.

[0085] Furthermore, the outer coil piece 30 and the inner coil piece 21 are combined to form a concentrically wound coil (hereafter referred to as the W-phase coil). The outer coil piece 30 is shaped to connect the slots of the stator 2 on the lead-out side 2a by placing the coil end at a position further outward than the radial position of the conductor entering the slot. The inner coil piece 21 is shaped to connect the slots of the stator 2b on the opposite lead-out side by placing it at a position further inward than the radial position of the conductor.

[0086] As described above, the length of the coil ends (coil pieces 30, 31) on the inner periphery is shorter than that of the coil ends (coil pieces 20, 21) on the outer periphery. Therefore, when wiring the coils, the outer coil piece 30 on the outer periphery is combined with the inner coil piece 21, and similarly, the outer coil piece 31 on the outer periphery is combined with the inner coil piece 20, so that the length of these coils is the same as the length of the central coil pieces 10, 11. This forms the coils of phase U, phase V, and phase W, thus preventing the generation of resistance differences between phases U, V, and W. Furthermore, by wiring the coil pieces 20 and 21 so that the portions exposed from the stator core 3 (coil ends) are inclined inward and the coil end portions are stacked in the direction of the rotation axis, and by wiring the coil pieces 30 and 31 so that the portions exposed from the stator core 3 (coil ends) are inclined outward and the coil end portions are stacked in the direction of the rotation axis, it is advantageous that the stator coil 9 can be assembled by inserting all the coil pieces parallel to the axial direction when inserting each coil piece (10, 11, 20, 21, 30, 31) into the slot 3c from both sides of the stator core 3 and taking out the coil pieces 41 to 46.

[0087] like Figure 1B , Figure 1C As shown in the projection diagram, when coil pieces 10 and 11 are arranged in a structure that connects two slots in the circumferential direction at a position with the same diameter as the radial position of the slot, the coils leading out from the slots in the portion covered by the coil need to be connected to the other side via either the inner or outer circumferential side. Furthermore, when these coil pieces are arranged in the circumferential direction at electrical angles of 180 degrees, they need to be shaped to avoid interference. Figures 1A to 1C The diagram only shows the amount of one pole in the formed coil. This structure completes the stator coil 9 of the rotary motor 1 by repeatedly arranging coil pieces in all the slots in the circumferential direction at an electrical angle of 180 degrees (mechanical angle of 45 degrees).

[0088] Figures 3A-3E This is a diagram used to illustrate the structure of the opposite side 2b of the stator 2 shown in Figure 1. Figure 3A The diagram shows a projection of a portion of the stator coil 9 extending to the opposite side 2b from the side of arrow 70 in Figure 1 along the direction of the rotation axis. Figure 3B This is a three-dimensional view taken from the inner circumference. Additionally, it should be noted that... Figure 3A , Figure 3B The objects shown in the diagram, coil piece 11 and coil piece 21, are similar to... Figure 1AThe circumferential position of the figure viewed from the direction of arrow 70 is offset (misaligned). As shown, the central coil piece 11 at the end of the coil is positioned at the same diameter as the conductor insertion position of slot 3c. Four coil pieces 11 of different radial dimensions are connected from one of the four slot insertion holes 66a to 66d of the winding frame 65 to the four insertion holes located five slots away circumferentially. At this time, the insertion holes 66a to 66d inserted at one end and the other end of the coil piece 11 are numbered the same from the inner circumferential side. Therefore, four coil pieces of different sizes are prepared as four coil pieces 11.

[0089] exist Figure 3C The diagram shows a perspective view of the shape of the central coil piece 11. The coil piece 11 is a conductor obtained by baking and coating a soft copper wire with an insulating varnish (Enamel). The coil piece 11 is formed by straight portions 11a and 11e, which are straight and housed in the slot 3c, extension portions 11b and 11d, which are connected to the straight portions 11a and 11e and extend to the outside of the slot 3c in the direction of rotation axis, and a connecting portion 11c connecting the ends of the extension portions 11b and 11d that are spaced apart from the connecting portion. The coil piece 11, which is composed of the portions 11a to 11e, is formed by bending a flat wire into a roughly U-shaped form, known as a hairpin. Here, in terms of the spatial arrangement of the stator coil 9 as a whole, in order to ensure the area of ​​the portion closer to the inner periphery than the connecting portion 11c of the coil piece 11, it is preferable to configure the extension portions 11b and 11d of the coil piece 11 to be bent slightly radially outward at an angle θ4 (θ4 is less than ten degrees). Furthermore, the bending radius R (radius of curvature) of the connection portion between the extension 11b and the connecting portion 11c is made relatively small to prevent interference with other coil sheets. Similarly, the bending radius R (radius of curvature) of the connection portion between the extension 11d and the connecting portion 11c is also made relatively small.

[0090] The end feet of the central coil piece 11 are in the shape of recesses 11f and 11g. Regarding this shape, the inner circumferential portion of the recess is punched or similarly cut, and the cut cross-section is electrolytically tin-plated to form a plating layer approximately 10 μm thick. Since the outer layer of the coil piece 11 has an insulating varnish film, no plating layer is formed; therefore, the plating layer is formed on the cut surface. For example... Figure 3B As shown, in the radially inner portion of the connecting portion 11c of the central coil piece 11, a portion of the coil end of the inner coil piece 21 (extensions 21b, 21d) is arranged to partially overlap in the direction of the rotation axis. Similarly, a portion of the coil end of the outer coil piece 31 (extensions 31b, 31d) is arranged to partially overlap in the direction of the rotation axis.

[0091] The inner coil piece 21 is formed in a roughly U-shape, consisting of straight portions 21a and 21e that extend to the outer side of the slot 3c in the direction of rotation axis, and a connecting portion 21c that connects the ends of the extension portions 21b and 21d that are spaced apart in the axial direction. The extension portions 21b and 21d of the coil piece 21 are configured to bend radially inward at an angle θ5 relative to the straight portions 21a and 21e. In addition, regarding the overall arrangement space of the stator coil 9, in order to ensure the arrangement space of the inner peripheral portion of the connecting portion 21c of the coil piece 21, the bending radius R of the connection portion between the extension portion 21b and the connecting portion 21c and the bending radius R of the connection portion between the extension portion 21d and the connecting portion 21c need to be relatively small so as not to interfere with other coil pieces.

[0092] The outer coil piece 31 is formed in a roughly U-shape, consisting of straight portions 31a and 31e that extend to the outer side of the slot 3c in the direction of rotation axis, and a connecting portion 31c that connects the ends of the extension portions 31b and 31d that are spaced apart in the axial direction. The extension portions 31b and 31d of the coil piece 31 are configured to bend radially outward at an angle θ6 relative to the straight portions 31a and 31e. In addition, regarding the overall arrangement space of the stator coil 9, in order to ensure the arrangement space of the connecting portion 31c of the coil piece 31 on the outer periphery, the bending radius R of the connection portion between the extension portion 31b and the connecting portion 31c and the bending radius R of the connection portion between the extension portion 31d and the connecting portion 31c need to be relatively small so as not to interfere with other coil pieces.

[0093] like Figure 3B When the inner coil sheet 21 is inserted as shown, the four connecting portions 21c are arranged to overlap in the direction of rotation. Similarly, four types of outer coil sheets 31 of different sizes are prepared and arranged as shown. Figure 3B When installed as shown, the four connecting parts 31c are arranged to overlap in the direction of the rotation axis.

[0094] like Figure 3BAs shown, for the connecting portions 11c of the four central coil pieces 11, four different sizes are prepared, arranged radially from the inner to the outer side at the same position along the rotation axis. The shape of the connecting portion 11c is not straight, but rather formed as an arc along the circumference of the stator core 3. The height of the coil end of this coil piece 11 (height from the stator core end) is h4. Furthermore, for the four inner coil pieces 21, four different sizes are prepared, and their connecting portions 21c are arranged radially at the same position, stacked in the axial direction. The shape of the connecting portion 21c is not straight, but rather formed as an arc along the circumference of the stator core 3. The maximum height of the coil end of the stacked coil pieces 21 (maximum height from the stator core end) is h5. Furthermore, four different sizes of outer coil pieces 31 are prepared, and their connecting portions 31c are arranged radially at the same position, stacked in the axial direction. The connecting portion 31c is not straight, but rather arc-shaped along the circumference of the stator core 3. The maximum height of the coil end of the stacked coil sheets 31 (the maximum height from the stator core end) is h6. Here, a relationship of height h4 > h5 and h4 > h6 is preferred. The relationship between h5 and h6 is arbitrary.

[0095] As described above, the inner coil piece 21 is shaped such that the flat line rising from the straight portions 21a and 21e bends radially inward without interfering with the connection portion 11c of the four central coil pieces 11, and does not protrude to a position further inward than the innermost diameter portion of the stator core 3. Figure 3B As shown, the coil piece 21 rising radially from the inner side of the slot 3c is configured with the lowest coil height. In the coil piece 21 at the next radial position, the coil height is increased in a way that ensures the thickness of the wire and a certain amount of gap, so that the connecting part 21c is positioned above the innermost coil piece 21. The connecting part 21c of the coil piece 21 rising from the next radial position (the third insertion hole from the inner side) is positioned higher, and the connecting part 21c of the coil piece 21 rising from the next radial position (the fourth insertion hole from the inner side) is positioned even higher. The inner coil piece 21 also has recesses 21f and 21g formed at the coil ends (the ends opposite to the coil ends in the straight portions 21a and 21e), similar to the central coil piece 11, and the cut surfaces are tin-plated.

[0096] Figure 3BIn the diagram, only the slot 3c where the coil piece 21 is inserted is shown, and the winding frame 65 is omitted, so that the shape and arrangement of the ends (21f, 21g) of the coil piece 21 can be seen. The concave side of the coil piece 21 is set to be shorter in the direction of the rotation axis than the lead-out side 2b of the stator core 3, and does not protrude from the end of the stator core 3. The recesses 21f, 21g are designed to fit into the protrusions 20f, 20g (described later in FIG. 4) at predetermined intervals on the inner side from the end. The axial positions of the recesses 11f, 11g, 31f, 31g formed at the ends are also the same in the other coil pieces, namely the central coil piece 11 and the outer coil piece 31.

[0097] The outer coil piece 31 is shaped such that the flat line rising from the straight sections 31a and 31e bends radially outward without interfering with the central coil piece 11. The outer coil piece 11 has ample margin on the back of the core, allowing it to be bent significantly outward. In this embodiment, the bending angle θ6 is set to a relatively large angle of approximately 45 degrees. At this time, as... Figure 3B As shown, the coil piece 11 standing upright from the innermost insertion hole has the highest coil height, forming the connecting portion 11c. The coil piece 11 in the second insertion hole has a lower coil height, positioned below the coil piece 11 standing upright from the first insertion hole, in a manner that ensures wire thickness and sufficient spacing. Similarly, the shape of each coil piece 11 is designed such that the connecting portion 11c of the coil piece 11 standing upright from the third insertion hole is further below, and the connecting portion 11c of the coil piece 11 standing upright from the fourth insertion hole is below it. At the ends of these outer coil pieces 11, recesses 31f and 31g are formed, similar to those on the inner coil pieces 31, and tin plating is applied.

[0098] Figures 4A to 4D It is used to explain the composition Figure 1A Partial structural diagram of the axial (lead wire side) structure of the stator core 3 of the stator 2 shown, and a perspective view for illustrating the shape of each coil. Figure 4A This is a partial axial projection of the lead-out side 2a of stator core 3. Figure 4B This is its three-dimensional view. On the lead-out side 2a of the stator core 3, there are lead-out coil pieces 41-46; therefore, the bridging method between slots 3c is the same as... Figure 3A , Figure 3B The situations are different.

[0099] Figure 4CThis is a perspective view of the central coil piece 10. The coil piece 10 is formed in a hairpin shape, or in other words, a roughly U-shaped shape, consisting of straight portions 10a and 10e, extending to the outer side of the slot 3c, extension portions 10b and 10d, and a connecting portion 10c connecting the ends of the extension portions 11b and 11d that are spaced apart in the axial direction. The extension portions 10b and 10d and the connecting portion 10c are coil ends. The extension portions 10b and 10d of the coil piece 10 are configured to bend radially outward at an angle θ1 relative to the straight portions 10a and 10e. Furthermore, in terms of the overall arrangement space of the stator coils 9, to ensure sufficient arrangement space for the portion of the connecting portion 10c on the outer periphery of the coil piece 10, the bending radius R of the connection portion between the extension portion 10b and the connecting portion 10c and the bending radius R of the connection portion between the extension portion 10d and the connecting portion 10c are relatively small, so as not to interfere with other coil pieces. The ends of coil sheet 10 are shaped (cut off) into protrusions 10f and 10g. Their dimensional relationships are such that they are suitable for pressing into and connecting symmetrical coil sheets 11 (see reference). Figure 2C The recesses 11f and 11g are fitted together in a shape. In addition, the cut surfaces of the recesses 11f and 11g are tin-plated in the same way as the protrusions 10f and 10g.

[0100] Lead-out coil pieces 41-43 are housed in the innermost insertion hole 66a among the plurality of insertion holes 66a-66d formed in the winding frame 65. The inner coil piece 20 is formed such that the insertion holes 66b-66d at the location of the lead-out coil piece 41 are connected to the outer coil piece 31 (see reference 2b) via the opposite side of the lead-out. Figure 3B The structure connects slots 66a to 66c on one side of slot 3c, which form concentric coils and span five slots (37.5 degrees) in the circumferential direction, to connect lead coil pieces 41 and 44. The central coil piece 10 is partially formed such that the insertion hole 66a at the innermost circumference of the position where the lead coil piece 42 is located is connected to the central coil piece 11 (see reference 2b) via the opposite side of the lead coil piece 2b. Figure 3B The structure forms a concentric coil by connecting the outermost insertion hole 66d of slot 3c, which spans five slots circumferentially, to the lead-out coil piece 45. Additionally, the central coil piece 10 is composed of three types of coil pieces: one connecting the starting slot insertion hole 66b to a slot insertion hole 66a spanning five slots circumferentially; one connecting the starting slot insertion hole 66c to a slot insertion hole 66b spanning five slots circumferentially; and one connecting the slot insertion hole 66d to a slot insertion hole 66c spanning five slots circumferentially. The outer coil piece 30 is partially formed such that the innermost circumferential insertion hole 66a of the lead-out coil piece 43 is connected to the inner coil piece 21 (see reference 2b) via the opposite side of the lead-out coil piece 2b. Figure 3BThe structure is formed by connecting the outermost insertion hole 66d of slot 3c, which spans 5 slots in the circumferential direction, to the lead coil piece 46.

[0101] exist Figure 4F The shape of lead-out coil piece 41 is shown. Lead-out coil pieces 41 to 46 have identical shapes, allowing the use of common components. Lead-out coil piece 41 is formed by bending a rectangular cross-section nickel-chromium alloy wire into a crank shape, consisting of a straight portion 41a, a bent portion 41b, and an extension portion 41c, creating a stepped structure near the center of the nickel-chromium alloy wire along its length, such as... Figure 4B As shown, the coil pieces 41 to 46 have a dimensional relationship that prevents them from interfering with each of the coil pieces 10, 20, and 30 during installation.

[0102] for Figure 4C , Figure 4D , Figure 4E The coil pieces 10, 20, and 30 shown are prepared in three slightly different sizes, and lead coil pieces 41 to 46 of the same size are prepared, thereby enabling the formation of lead coil pieces 2a on the stator 2. Figure 4A The stator coil 9 of phase 1 is shown. The leads (41-43) on the radially inner side of the stator coil 9 are shaped to protrude to a position further inward than the innermost position of the stator core 3. This is because there is no margin in the inner part in this embodiment, but if a design with margin in the inner part is adopted, it is also possible to configure the lead coil pieces 41-43 to be positioned further outward than the inner diameter of the stator 2. In addition, the length of the straight portion (10a, 10e, 20a, 20e, 30a, 30e, 41a, etc.) of each coil piece is formed to be longer than the length of the lead-out side 2a of the stator core 3, and the ends of the forming protrusions (10f, 10g, 20f, 20g, 30f, 30g, 41f, etc.) of each coil piece are configured to protrude into the stator core 3 to the opposite lead-out side 2b.

[0103] Figure 5A This is a perspective view of the stator 2 of a radial gap type rotary motor 1 according to an embodiment of the present invention, showing a state in which all coils are installed in the circumferential direction by concentric winding of flat conductors. Figure 5B This is a perspective view of the lead-out side 2a portion of stator 2 (before it is joined to the lead-out side 2b portion). Figure 2BThis is a perspective view of the stator 2 on the opposite side 2b (before it is joined with the stator on the opposite side 2a), showing a perspective view when viewed from the opposite side in the direction of the rotation axis (from the direction of arrow 70 in Figure 1). The stator on the stator on the opposite side 2b and the stator on the opposite side 2b are combined in the direction of the rotation axis. Inside the winding frame 65 and on the side of the opposite side 2b, the concave portions (10f, 10g, 20f, 20g, 30f, 30g, 41f, etc.) and the convex portions (11f, 11g, 21f, 21g, 31f, 31g) fit together to form a coil. At this point, as shown in Figure 1, in order to equalize the resistance value of the coil, the inner coil piece 20 on the lead-out side 2a and the outer coil piece 31 on the opposite lead-out side 2b are combined axially and concentrically wound, and the outer coil piece 30 on the lead-out side 2a and the inner coil piece 21 on the opposite lead-out side 2b are combined axially and concentrically wound. Near the radial center, the central coil piece 10 on the lead-out side 2a and the central coil piece 11 on the opposite lead-out side 2b are combined to form a concentric winding, and the assembly is performed in this way. Furthermore, when the lengths of the rotation axis Ax of the lead-out side 2a and the stator core 3 on the opposite side of the split structure are equal, the lengths of the straight portions 10a, 10e, 20a, 20e, 30a, and 30e of the coil sheets 10, 20, and 30 on the lead-out side 2a are formed to be longer than the lengths of the straight portions 11a, 11e, 21a, 21e, 31a, and 31e of the coil sheets 11, 21, and 31 on the opposite side of the lead-out side 2b.

[0104] Next, the winding structure of the stator coil 9 in this embodiment will be described. Before describing the structure of this embodiment, the following will be used... Figures 6A to 6C , Figures 7A to 7C Describe the winding structure of existing coils. Figure 6A This is a perspective view showing the structure of one phase of a stator using a waveform winding structure of flat wires, as in a conventional example. Figure 6B This is a circuit diagram of two parallel delta connections. Figure 6C This represents its connection diagram. Figure 6A It shows Figure 6C The upper part.

[0105] The small numbers with circles, namely circles 1 and 8, are lead wires. The coil entering from the inner lead wire circle 1 is connected via the lower coil end to the second insertion hole of slot 43, which is 6 slots apart circumferentially. It is then connected via the upper coil end to slot 37, which is 6 slots apart circumferentially. Afterwards, via the lower coil end, it passes through slots 31, 25, 19, and 13, connected by a short-pitch coil 17 to slot 8, which spans 5 slots circumferentially. Then, a coil spanning 6 slots is passed through slots 2, 44, 38, 26, 20, and 14, completing one revolution. Next, a long-pitch coil 16 is connected and transferred to the third insertion hole, and starting from slot 1, it is rotated 2 revolutions in the same manner. The lead wire exits from the fourth insertion hole of slot 8. This is the U-phase of system 1 with circles 1 and 8 as terminals, connected as follows: Figure 6B System 1 has a U-phase coil 18. Similarly, the U-phase coil that enters from circle 14 and connects to circle 7 constitutes system 2. Its connection is as follows: Figure 6B The U-phase coil 19 of system 2. It can be seen that when the waveform is wound, the configuration is to connect the divided coil pieces in the circumferential direction, so the number of coils cannot be more than the number of slots per pole per phase. In the case of 8 poles and 48 slots, there are 2 coils per phase.

[0106] Figure 7A This is a perspective view showing the structure of one phase of a stator using a wave-wound structure of flat wire, another existing example. Figure 7B This is a circuit diagram of two series delta connections. Figure 7C This represents its connection diagram. In Figure 6A In the waveform winding shown, the number of coils is 2. Therefore, in addition to the two sets of delta connections shown in Figure 6, it is also possible to construct one set of delta connections in which two coils of the same phase are connected in series. That is, as shown... Figure 7B As shown, the two coils forming phase U, coils 1-8 and coils 14-7, are connected in series. Similarly, the two coils of the same phase in other phases are connected in series and then delta-connected. This structure is thus achieved. Because this structure is possible, multiple voltage specifications, such as 200V and 400V, can be achieved using the same winding structure and only changing the wiring. Additionally, as other structures not shown, a Y-connection (star connection) can be used, or a configuration of two series 1Y connection and two Y parallel connections can be constructed. However, because the number of turns cannot be changed, the voltage change is 1.73 times.

[0107] Next, the winding structure of the stator coil 9 in this embodiment will be described. Figure 8A This is a perspective view showing the structure of one phase of the stator using a concentric winding structure of flat wires according to the present invention. Figure 8B This is a circuit diagram of two parallel delta connections. Figure 8C This represents its connection diagram. Figures 8A to 8C Only the U-phase coil is shown in the diagram. Figure 8C and Figure 6C By comparison, it can be seen that the U-phase coils are in the same slot. In this embodiment, because it is constructed by concentric winding, it consists of 8 partial coils in 5 slots (spanning 37.5 degrees) (coils numbered 2 and 7, 8 and 13, 14 and 19, 20 and 25, 26 and 31, 32 and 37, 38 and 43, and 44 and 1). Figure 8C In this system, four concentrically wound partial coils are connected in series to form partial coil group 28 of system 1 and partial coil group 29 of system 2. By connecting partial coil group 28 of system 1 to... Figure 8B The U-phase coil section forms stator coil 50a, and the portion of coil group 29 of system 2 connected to another delta-connected U-phase section forms stator coil 50b, thus becoming... Figure 8B The circuit diagram of the coil.

[0108] Figure 9A This is a perspective view showing the structure of another phase of the stator 2 using a concentric winding structure of flat wires according to the present invention. Figure 9B This is a circuit diagram of two series delta connections. Figure 9C This represents its connection diagram. (And...) Figure 7A Similarly, in existing examples, two coil groups 28 and 29 can be formed in a concentric winding structure, and therefore these two coil groups can be connected in series, such as... Figure 9B The diagram shows a set of delta connections. This allows for the construction of motors capable of handling both 200V and 400V motors.

[0109] Figure 10A This is a circuit diagram of an eight-parallel delta connection using a concentrically wound flat wire for one phase of the stator 2 according to the present invention. Figure 10B This represents its connection diagram. For example... Figure 10B As shown, in the case of concentric winding, eight coils 32 to 39 are used. Therefore, a connection structure of up to eight coils in parallel can be achieved. Figure 10A , Figure 10B This illustrates the structure of an eight-parallel delta connection where all coils are connected in parallel, as shown in the example. Figure 10B As shown, by using each concentrically wound coil as coil 32-39, eight coils can be connected in parallel. Of course, two coils in series and four coils in parallel can also be used. Therefore, it can accommodate four voltage specifications.

[0110] Figure 11This is a circuit diagram of the control system for a rotating electric motor that uses two inverter devices to drive a concentrically wound stator 2. In a high-capacity rotating electric motor 1A, compared to increasing the capacity of the drive circuit (inverter device) and using one drive circuit to drive one rotating electric motor, dividing the drive circuit into two can sometimes reduce the manufacturing cost of the circuit. Furthermore, there are cases where multiple control circuits are used for driving the motor, for reasons such as distributing heat generated by the power devices in the drive circuit. In this case, a method is adopted where the winding is divided into two and each drive circuit (inverter device) handles the load.

[0111] Figure 11 The connection structure is shown, with control circuit 52a of system 1 connected to stator coil 50a of system 1, and control circuit 52b of system 2 connected to stator coil 50b of system 2 for driving. The power supplies of control circuits 52a and 52b are connected to different systems, generating DC power through their respective rectifier circuits 51a and 51b, which are then used for PWM (Pulse Width Modulation) switching to drive the rotary motor. A drive device with a microcomputer is provided to control the ON / OFF of the gate signals of control circuits 52a and 52b. Figure 11 Not shown in the diagram. It can be seen that with this structure, the windings of the rotary motor 1 must be at least two sets, such as 50a and 50b. Figure 6A , Figure 7A In the example of waveform winding shown, only two in-phase windings can be formed. Therefore, although it is possible to switch between 200V and 400V specifications, a drive method using two control circuits cannot be used when the 400V specification (two series and one delta connection) is applied. That is, it can be seen that in order to achieve voltage specification switching and drive with two control circuits using a rotary motor 1 with one winding specification, more than four coils are required per phase. In the case of the concentric winding structure of the present invention, it is possible to divide into up to eight coils, thus achieving this.

[0112] exist Figure 12 The image shows a model of the coil slot configuration of a stator 202 using a wave-wound structure with flat wires. Figure 13A , Figure 13B The diagram shows the calculated flux linkages obtained using this model for magnetic field analysis. For example... Figure 11 When two control circuits are used to drive two coil groups, as shown, magnetic interference between the coils becomes a problem. When the coupling coefficient between the two coils is high, and the operation of one control circuit is inconsistent with the other, an induced electromotive force is generated between the coils, causing current distortion. Figure 13A The result was obtained by confirming the phenomenon through magnetic field analysis. Figure 13A The slot configuration during waveform winding is shown in slot 204, where coils U1 and U2 of system 1 are alternately present in one slot 204. The other phases are the same, with V1 and V2 of system 1 alternately present in one slot, and W1 and W2 of system 1 alternately present.

[0113] exist Figure 13A The diagram shows the result of a linked magnetic flux being generated in another coil (system 2) when a sine wave is applied to one of the coils (system 1). Figure 13A The horizontal axis represents time (in seconds), and the vertical axis represents the linkage flux (Wb). Three-phase AC was analyzed; only phase U is shown here. Solid lines represent the flux of u1 on the side where current is applied, and dashed lines represent the flux of u2 where linkage flux is detected. Because both are identical, only solid lines are shown in the figure. Figure 13B The diagram shows the linkage flux and coupling coefficients of the three phases. The coupling coefficients of all three phases are 1, confirming a high degree of magnetic influence. This indicates that the waveform-wound coil is not suitable for driving with two drive circuits.

[0114] exist Figure 14 The diagram shows a model of the stator 2's coil slot configuration using a concentric winding structure with flat wires, as shown in this embodiment. In the calculation model for the concentric winding case, only coils of the same system are located in the same slot; for example, only the V1 phase coil is configured in slot 301. This circuit is the case of a two-parallel delta connection as shown in Figure 8. The dotted line indicated by reference numeral 71 represents the boundary between coils U1 and U2. Figure 15B The diagram shows the calculated results of the interference from the linked magnetic flux of the coil obtained by using this model for magnetic field analysis. In the case of concentric winding, consisting of four coils grouped together in the circumferential direction, the influence on the coils outside the boundary can be considered relatively small. A comparison is made between u1 and u2, and... Figure 13A The results of the two are consistent but different, such as Figure 15A As shown, the result is that the linkage flux of coil u2 is smaller than that of coil u1, such as... Figure 15B As shown, the coupling coefficient is around 0.1, indicating that the magnetic interference is relatively small.

[0115] Next, using Figures 16A to 16H The assembly sequence of the concentrically wound stator 2 in this embodiment is explained. Among them, Figure 16A , Figure 16C , Figure 16E , Figure 16G This is a projection view of the insertion assembly side (lead-out side) of stator 2. Figure 16B , Figure 16D , Figure 16F , Figure 16H yes Figure 16A , Figure 16C , Figure 16E , Figure 16GThe three-dimensional diagrams of the stator 2 in their respective states (phase 1).

[0116] Figure 16A The stator core 3 indicates the assembled state. From this state onwards, coil pieces are inserted into the insertion holes 66a to 66d of the winding frame 65 in slot 3c, considering the assembly sequence. Figure 16B yes Figure 16A A three-dimensional view of the stator 2 in its state. Figure 16B The diagram shows the completed assembly of coil pieces 11, 21, and 31 extending from opposite sides.

[0117] Figure 16C Indicates from Figure 16A The state is such that lead coil pieces 41 to 43 are inserted into the insertion hole 66a on the inner circumference side, and lead coil pieces 44 to 46 are inserted into the slot insertion hole 66d on the outer circumference side. Figure 16D yes Figure 16C A three-dimensional view of stator 2. Figure 16C , Figure 16D In this process, lead coil pieces 41-43 are repeatedly inserted into the slot at the starting point 60 and into slots spaced one slot apart, thereby inserting one circumferential turn (one full circle) of lead coil pieces 41-43. Regarding the outer lead coil pieces 44-46, one circumferential turn of lead coil pieces 44-46 is inserted from a position five slots away from the starting point 60. Furthermore, the insertion order of lead coil pieces 41-46 is arbitrary; in the inner circumferential insertion hole 66a, lead wires (41-43) are inserted every other slot circumferentially, and in the outer circumferential insertion hole 66d, lead wires (44-46) are inserted sequentially or randomly every other slot circumferentially. (Observation) Figure 16C As can be seen from the projection diagram, after inserting lead coil pieces 41 and 42, the insertion holes other than those for which lead coil pieces 41 and 42 are inserted are also visible on the projection plane. Similarly, for the inner peripheral insertion holes 66a constituting other phases, lead coil pieces 41 to 46 are inserted in a circumferential direction at intervals of one slot. For the outer peripheral insertion holes 66d, lead coil pieces 44 to 46 are similarly inserted in a circumferential direction at intervals of one slot.

[0118] Figure 16EIn this process, three inner coil pieces 20 and three outer coil pieces 30 are inserted. Inner coil pieces 20 are inserted into the second insertion hole 66b (starting from the inner side of the starting point 60) and the insertion hole 66b (moving away from the starting point 60 by five slots circumferentially). Similarly, coil pieces 20 are inserted into the outer insertion hole 66c, and then into the outermost insertion hole 66d. In this way, inner coil pieces 20 are inserted sequentially from the second inner insertion hole 66b to the fourth insertion hole 66d. As a result, the coil pieces 20 inserted in the insertion hole 66d have their connecting portions 20c at the top and the coil pieces 20 inserted in the insertion hole 66b have their connecting portions 20c at the bottom. For each insertion of three coil pieces 20 as described above, three more coil pieces 20 are inserted again, starting from the position 10 slots circumferentially away from the starting point 60. This operation is repeated six times (six layers) throughout the entire circumference.

[0119] The outer coil piece 30 is first inserted into the third insertion hole 66c, which is located four slots away from the starting point 60 in the circumferential direction, and into the insertion hole 66c, which is located nine slots away from the starting point 60 in the circumferential direction. The outer coil pieces 30 are inserted sequentially from the third insertion hole on the outside inwards. First, the lead coil pieces 44 and 46 are inserted into the fourth insertion hole on the outside (insertion hole 4), then the coil piece 30 is inserted into the third insertion hole (insertion hole 3), then the coil piece 30 is inserted into the second insertion hole (insertion hole 2), and finally the coil piece 30 is inserted into the first insertion hole (insertion hole 1). At this time, the bent portions 46b of the lead-out coil pieces 44 and 46 are positioned close to the stator core 3. The connecting portion 30c of the coil piece 30 inserted into the third insertion hole is located adjacent to it in the direction of the rotation axis. The connecting portion 30c of the coil piece 30 inserted into the second insertion hole is located adjacent to it. The connecting portion 30c of the coil piece 30 inserted into the first insertion hole is located furthest from the stator core 3. Through this stacking, the coil pieces are inserted sequentially starting from the coil piece with the lowest coil end height. Figure 16E As shown in the projection diagram, it can be confirmed that after inserting coil pieces 20 and 30, the insertion holes 66a to 66d indicated by arrows 72a and 72b for inserting the central coil piece are also visible in the direction of the rotation axis.

[0120] Next, as Figure 16G , Figure 16H As shown, in Figure 16EThree central coil pieces 10 are inserted at each of the positions indicated by arrows 72a and 72b. The central coil piece 10 is first inserted into the outermost insertion hole 66d of the second slot circumferentially starting from the starting point 60 and the third insertion hole 66c of the seventh slot circumferentially starting from the starting point 60. Then, it is inserted into the third insertion hole 66c of the second slot circumferentially starting from the starting point 60 and the second insertion hole 66b of the seventh slot circumferentially starting from the starting point 60. Finally, it is inserted into the second insertion hole 66b of the slot circumferentially moving away from the starting point 60 by two slots and the innermost insertion hole 66a of the slot circumferentially moving away from the starting point 60 by seven slots. In this embodiment, the coil end of the coil piece 10 is as follows... Figure 4C The coil pieces are tilted outward at an angle θ1 of about 5 degrees, so it is preferable to insert the coil pieces 10 sequentially starting from the fourth insertion hole (insertion hole 4) on the outside. In addition, the connecting portions 10c of the three types of inserted coil pieces 10 are arranged radially at the same height H1 in the axial direction.

[0121] For the insertion of the three central coil pieces 10 as described above, starting from the starting point 60 and moving 10 slots away in the circumferential direction as the next starting point, insert three more coil pieces 10. This operation is repeated six times (six layers) along the entire circumferential direction. This completes the assembly of the stator coil 9 on the lead-out side, resulting in the following state: Figure 5B The state.

[0122] The assembly sequence of coil segments 11, 21, and 31 on the opposite side of the stator core 3 is basically the same as... Figure 16E , Figure 16G The assembly method is the same. On the opposite side 2b, no lead wires corresponding to reference numerals 41-46 are used; therefore, four coil pieces 11, 21, and 31 are inserted. First, insert the inner coil piece 21 sequentially into slot 3c from the first to the fourth insertion hole, repeating this operation for eight phases in the circumferential direction. Next, insert the outer coil piece 31 sequentially into slot 3c from the fourth to the first insertion hole, repeating this operation for eight phases in the circumferential direction. Next, insert the central coil piece 11 sequentially into slot 11 sequentially from the fourth slot to the first slot, repeating this operation for eight phases in the circumferential direction, thereby completing the assembly of the coil pieces on the opposite side 2b. This completed state is... Figure 5C The state shown is correct. Furthermore, the insertion order of these coil pieces does not need to be as described above. For example, the assembly order of the inner coil piece 20 and the outer coil piece 30 can be reversed, with the outer coil piece 30 inserted first, followed by the inner coil piece 20.

[0123] like Figure 5B , Figure 5CThe stator core 3 on the lead-out side 2a and the stator core 3 on the opposite lead-out side 2b, as shown, are temporarily fixed in such a way that the coil end portions of each coil piece do not move in the direction of the rotation axis. The stator cores on the lead-out side 2a and the opposite lead-out side 2b are joined together, thereby causing the protrusions of coil pieces 10, 20, 30, 41 to 46 to fit into the recesses of 11, 21, and 31. Through this process, the mechanical assembly of the stator 2 is completed.

[0124] observe Figure 6A As can be seen, in the existing waveform-wound coil sheets, because adjacent coil sheets are intertwined, they cannot be assembled sequentially one by one. They must be installed together in slot 3c while still fixed together before being inserted into the winding frame of the stator core. Furthermore, once assembled, it is difficult to remove the coil sheets individually. It can be considered that the concentric winding structure of the interlocking coil sheets 10, 11, 20, 21, 30, and 31 in this embodiment also has an advantage in terms of ease of coil assembly compared to waveform winding.

[0125] According to the present invention, for the inner coil pieces 20 and 21, respectively combined with the outer coil pieces 30 and 31 with longer coil ends, the central coil pieces 10 and 11, which are connected circumferentially at the same diameter as the radial position of the slot, are designed so that their circumference is the same as that of the coil formed by connecting the inner and outer coil pieces, i.e., their resistance values ​​are consistent. Therefore, even using a concentric winding structure made of flat conductors, the resistance and inductance of the coil can be balanced.

[0126] By employing the coil structure of the present invention, a concentrically wound stator coil 9 with a high conductor area ratio and low interphase coil resistance deviation can be constructed. Therefore, the characteristics of the concentrically wound coil structure can be utilized for motor and system design. Furthermore, because the number of coils is independent of the number of slots per pole and per phase, there is greater design freedom in whether to form a series or parallel circuit during wiring, making it easier to adapt to different voltage specifications and frequencies (speed, torque). With concentric winding, it is possible to design the number of turns in each slot to be odd, which is not possible with waveform winding, thus increasing design freedom to adapt to the aforementioned specification changes. Moreover, because the coils are independent structures within the system, magnetic interference is reduced, thus reducing constraints on the number of drive circuits used. Furthermore, during the stator coil concave-convex fitting assembly, by appropriately adjusting the coil insertion order, it is advantageous to perform assembly by performing concave-convex fitting processing simultaneously with insertion. In addition, the present invention is not limited to the above embodiments, and various modifications can be made without departing from its spirit.

[0127] Explanation of reference numerals in the attached figures

[0128] 1, 1A… Rotary motor, 2… Stator, 2a… Lead-out side, 2b… Opposite lead-out side, 3… Stator core, 3a… Back core, 3b… Tooth core, 3c… Slot, 3d… Recess, 4… Housing, 4a… Main body, 4b, 4c… End support, 5… Rotating shaft, 6… Rotor, 7… Rotor core, 8… Permanent magnet, 9… Stator coil, 10, 11… Central coil piece, 11a, 11e… Straight section, 11b, 11d… Extension section, 11c… Connecting section, 15… Standard pitch coil, 16… Long pitch coil, 17… Short pitch coil, 18… U-phase coil of system 1, 19… U-phase coil of system 2, 20, 21… Inner coil piece, 28… (First) part of the coil group, 29… (Second) part of the coil group, 30, 31… …Outer coil pieces, 32~39……(1~8) concentric winding coil groups, 41~46……lead coil pieces, 50a……(System 1) winding, 50b……(System 2) winding, 51……rectifier (converter), 52a, 52b……control circuit (inverter device), 53a, 53b……system power supply (three-phase), 65……resin winding frame, 66a~66d……insertion holes, 67, 68……flange, 67a, 68a……claw, 100……air compressor, 101……compression mechanism, 102……box, 105……first shaft, 110……first bevel gear, 120……M rotor, 130……second bevel gear, 135……second shaft, 140……F rotor, 145……tooth space (tooth space), 202……stator, Ax……rotor axis.

Claims

1. A rotary electric motor, characterized in that, include: A rotor fixed on a rotating shaft; and The stator forms a coil by inserting and connecting multiple U-shaped coil pieces made of flat wires into the slots formed in the circumferential direction of the rotation axis of the stator core, which has multiple slots for receiving the flat wires. The coil sheet is formed of flat wire and has: two straight portions that are housed in slots spaced apart in the circumferential direction; and a coil end that connects the two straight portions, extending outward from the straight portions in the direction of the rotation axis. The coil plates are prepared as a central coil plate, an inner coil plate, and an outer coil plate, wherein... When viewed from above along the rotation axis, the straight portion of the central coil plate and the coil end are arranged on a circumference. The coil end of the inner coil sheet is bent radially inward relative to the receiving portion housed in the slot. The coil end of the outer coil plate is bent radially outward relative to the receiving portion housed in the slot. The coils are formed such that the circumferential length of the coil end of the inner coil piece is shorter than the circumferential length of the coil end of the central coil piece, and the circumferential length of the coil end of the outer coil piece is longer than the circumferential length of the coil end of the central coil piece. A pair of central coil plates are inserted into the first slot group from one side or the other side of the rotation axis and are electrically connected. The inner coil and the outer coil are inserted into the second or third slot group from one side or the other side of the rotation axis and electrically connected, thereby forming a concentrically wound stator coil.

2. The rotary motor as described in claim 1, characterized in that: The coil end is formed by two extensions extending outward from the straight portion of the coil sheet in the direction of rotation axis, and a connecting portion connecting the ends of the extensions in the circumferential direction. After the stator coils are wired and formed, the connecting portions of the central coil plates are arranged in a radially aligned manner. The angle is set such that the extension of the inner coil sheet is bent radially inward, and the connecting portion of the inner coil sheet is arranged in a stacked manner in the direction of the rotation axis in a portion that is radially inward than the stacked portion of the central coil sheet. The angle is set such that the extension of the outer coil sheet is bent radially outward, and the connecting portion of the outer coil sheet is arranged in a stacked manner in the direction of the rotation axis in a portion that is radially outward of the stacked portion of the connecting portion of the central coil sheet.

3. The rotary motor as described in claim 2, characterized in that: The angle at which the extension of the inner coil sheet bends inward relative to the straight portion is greater than 0 degrees and less than 45 degrees. The angle at which the extension of the outer coil plate bends outward relative to the straight portion is greater than 0 degrees and less than 45 degrees. The length of a coil formed by alternately connecting the inner coil piece and the outer coil piece is the same as the length of a coil formed by the two central coil pieces.

4. The rotary motor as described in claim 3, characterized in that: When the coil pieces are inserted into the slots of the stator core from both sides of the rotation axis direction, the central coil piece, the inner coil piece, and the outer coil piece can be inserted and assembled one by one in parallel with the rotation axis direction.

5. The rotary motor as described in claim 1, characterized in that: By forming the stator coils using concentric winding, it is possible to construct a parallel number greater than the number of slots per pole per phase.

6. The rotary motor as described in claim 3, characterized in that: The stator core is composed of a back core and multiple tooth cores combined with the back core. The tooth core is made of a low-loss soft magnetic material, and In the grooves between adjacent tooth cores, resin winding frames that radially accommodate multiple flat wires are respectively arranged.

7. The rotary electric motor as described in claim 3, characterized in that: It is configured to handle multiple voltage specifications and multiple control devices simultaneously using a single winding specification.

8. The rotary motor as described in claim 3, characterized in that: An odd number of turns are formed in one of the slots.

9. A control system for a rotating electric motor, characterized in that: The rotary motor is the rotary motor according to claim 3. The stator coil adopts a parallel triangular winding structure. Each of the triangular winding sections is connected to multiple inverter devices. It is configured to independently supply excitation voltage to the triangular winding portion via the inverter device.

10. The control system for the rotating electric motor as described in claim 9, characterized in that: Each inverter device is equipped with a converter circuit corresponding to the inverter device, and the converter circuit is powered by an independent system power supply.

11. A method for manufacturing a stator in a rotating electric motor, characterized in that: The rotary electric motor includes: a rotor fixed on a rotating shaft; and a stator disposed on the outer periphery of the rotor, the stator having: a stator core having a plurality of slots formed in the circumferential direction; and stator coils formed by a plurality of U-shaped coil plates formed of flat wire inserted into the slots from the lead-out side or the opposite lead-out side in the direction of the rotating shaft. In the rotary motor, a winding frame is arranged in each of the slots, and the winding frame has radial slots for receiving m of the flat wires. For the coil piece inserted from the lead-out side in the direction of the rotation axis, perform the following steps a to d: Step a: As a group of coil pieces formed by two straight sections and coil ends, prepare m-1 types of central coil pieces, m-1 types of outer coil pieces, and m-1 types of inner coil pieces. The two straight sections are housed in slots that are circumferentially spaced from each other by five slots. The coil ends are formed to extend outward from the straight sections in the direction of the rotation axis, extending in both the rotation axis direction and the circumferential direction to connect the two straight sections. The outer coil pieces are bent such that the coil ends are bent radially outward, and the inner coil pieces are bent such that the coil ends are bent radially inward. Step b: Starting from the slot that serves as the starting point of the inner coil sheet, insert m-1 types of inner coil sheets circumferentially in a manner that radially stacks the connecting portions of the coil ends of m-1 types of inner coil sheets extending in the circumferential direction. Step c: Starting from the slot at a position circumferentially away from the starting point of the inner coil sheet by four slots, insert m-1 types of outer coil sheets in a manner that stacks the connecting portions of the coil ends of m-1 types of outer coil sheets extending circumferentially in the direction of the rotation axis. Step d: Starting from a position two slots away in the circumferential direction relative to the starting point, insert m-1 types of central coil sheets circumferentially in such a radially arranged manner that the connecting portions extending in the circumferential direction from the coil ends of m-1 types of central coil sheets are arranged. For the coil piece inserted from the opposite side of the rotation axis direction, perform the following steps e to h: Step e, as a group of coil pieces formed by two straight sections and coil ends, prepare m types of central coil pieces, m types of outer coil pieces, and m types of inner coil pieces, wherein the two straight sections are housed in slots that are circumferentially spaced from each other by five slots, the coil ends are formed to extend outward from the straight sections in the direction of the rotation axis, and extend in the rotation axis direction and circumferential direction to connect the two straight sections, the outer coil pieces are bent such that the coil ends are bent radially outward, and the inner coil pieces are bent such that the coil ends are bent radially inward. Step f: Starting from the slot that serves as the starting point of the inner coil sheet, insert m-1 types of inner coil sheets circumferentially in a manner that radially stacks the connecting portions extending circumferentially from the coil ends of m-1 types of inner coil sheets. Step g: Starting from the slot at a position circumferentially away from the starting point of the inner coil sheet by four slots, insert m-1 types of outer coil sheets in a manner that stacks the connecting portions of the coil ends of m-1 types of outer coil sheets extending circumferentially in the direction of the rotation axis. Step h, starting from a position two slots away in the circumferential direction relative to the starting point, insert m-1 types of central coil sheets circumferentially in such a radially arranged manner that the connecting portions extending in the circumferential direction from the coil ends of m-1 types of central coil sheets are arranged. A concentrically wound coil is formed by connecting the group of coil pieces inserted into the slot of the stator core from the lead-out side and the group of coil pieces inserted from the opposite lead-out side within the slot.

12. The method for manufacturing the stator in a rotating electric motor as described in claim 11, characterized in that: Prepare multiple lead wires that will bend straight, flat lines into crank-shaped forms. On the lead-out side in the direction of the rotation axis, Before performing step b, a lead-out piece is placed in the innermost circumferential slot on the starting side of the inner coil piece, and a lead-out piece is placed in the outermost circumferential slot on the other side. Before performing step c, a lead-out piece is placed in the innermost circumferential slot on the starting side of the outer coil piece, and a lead-out piece is placed in the outermost circumferential slot on the other side. Before performing step d, a lead-out piece is arranged in the innermost circumferential groove on one side of the groove for receiving the central coil piece, and a lead-out piece is arranged in the outermost circumferential groove on the other side.

13. The method for manufacturing the stator in a rotating electric machine as described in claim 12, characterized in that: A protrusion or a recess is formed at the open end of the inner coil sheet, the central coil sheet, and the lead-out sheet on the lead-out side. On the opposite side of the lead-out, the open ends of the inner coil sheet, the inner coil sheet, and the central coil sheet form recesses or protrusions corresponding to the lead-out side. The coil pieces are electrically connected by fitting the protrusions and recesses of the coil pieces on the lead-out side and the opposite side of the lead-out into the slots of the winding frame.

14. The method for manufacturing the stator in a rotating electric machine as described in claim 13, characterized in that: This allows the execution order of assembly in step b and assembly in step c to be reversed. It can reverse the execution order of the assembly in step f and the assembly in step g.

15. The method for manufacturing the stator in a rotating electric machine as described in claim 14, characterized in that: The coils are formed such that the circumferential length of the coil end of the inner coil piece is shorter than the circumferential length of the coil end of the central coil piece, and the circumferential length of the coil end of the outer coil piece is longer than the circumferential length of the coil end of the central coil piece. Connect the central coil piece on the lead-out side to the central coil piece on the opposite lead-out side. Connect the inner coil piece on the lead-out side to the outer coil piece on the opposite lead-out side. The outer coil piece on the lead-out side is connected to the inner coil piece on the opposite lead-out side, thereby making the circumferential length of the concentric portions consistent.

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