Rotating electrical machinery and control systems

Abstract

Improves current response. [Solution] The rotating electric machine 1 comprises a rotor 2 having a plurality of salient poles 23, and a stator 3 arranged at a distance from the outer circumferential surface of the rotor 2. The stator 3 comprises an annularly formed back yoke 30, and a plurality of teeth 31 that protrude radially inward from the back yoke 30 and form slots 32 in which coils 55 on which main windings 54 are wound are arranged. The back yoke 30 comprises an annularly formed yoke body 35, a first excitation part 36 formed on the inner circumference side of the yoke body 35 and generating a magnetic field, and a second excitation part 37 formed on the outer circumference side of the first excitation part 36 in the yoke body 35 and generating a magnetic field.

Description

[Technical Field]

[0001] The present invention relates to a rotating electrical machine and a control system. [Background Art]

[0002] Conventionally, SR (Switched Reluctance) motors that do not use permanent magnets are known. Patent Document 1 discloses a drive circuit for a reluctance motor including a stator having a plurality of salient poles and a rotor having a plurality of salient poles. The drive circuit includes a first path for supplying an excitation current to at least a part of a coil wound around the salient poles of the stator or the rotor, and a second path for supplying a demagnetization current to a different part of the coil that does not overlap with at least the aforementioned part of the coil. According to this configuration, an induced current can be released with a smaller number of turns when the coil is demagnetized, and the time until the current converges can be shortened. [Prior Art Literature] [Patent Literature]

[0003] [Patent Document 1] International Publication No. 2016 / 017337 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] The technology disclosed in Patent Document 1 only shortens the time until current converges when the current falls, and does not consider the period when the current rises. Therefore, it is desired to improve current response while also taking into consideration the rising period of the current.

[0005] In order to solve the above problem, the present application aims to improve current response. [Means for Solving the Problem]

[0006] As a means for solving the above problem, an aspect of the present invention has the following configuration. (1) A rotating electric machine according to an embodiment of the present invention (for example, rotating electric machine 1 in the embodiment) comprises a rotor (for example, rotor 2 in the embodiment) having a plurality of salient poles (for example, salient poles 23 in the embodiment), and a stator (for example, stator 3 in the embodiment) arranged at a distance from the outer circumferential surface of the rotor, wherein the stator comprises an annularly formed back yoke (for example, back yoke 30 in the embodiment), and a coil (for example, main winding 54 in the embodiment) that protrudes radially inward from the back yoke and around which the main winding is wound (for example, in the embodiment The back yoke comprises a plurality of teeth (e.g., teeth 31 in the embodiment) forming a slot (e.g., slot 32 in the embodiment) in which a 55) is arranged, and the back yoke has an annularly formed yoke body (e.g., yoke body 35 in the embodiment), a first excitation unit (e.g., first excitation unit 36 ​​in the embodiment) formed on the inner circumference side of the yoke body and generating a magnetic field, and a second excitation unit (e.g., second excitation unit 37 in the embodiment) formed on the outer circumference side of the first excitation unit in the yoke body and generating a magnetic field.

[0007] (2) In the rotating electric machine described in (1) above, the first excitation unit is provided with a coil (for example, a coil 65 in the embodiment) around which an auxiliary winding (for example, an auxiliary winding 64 in the embodiment) is wound, and the first excitation unit may be formed in a concave shape (for example, a concave shape 36a in the embodiment) with respect to the inner circumferential surface of the yoke body.

[0008] (3) In the rotating electric machine described in (2) above, the first excitation unit may be formed in a convex shape (for example, the convex shape 36b in the embodiment) with respect to the axial end face of the yoke body.

[0009] (4) In the rotating electric machine described in any of (1) to (3) above, both ends of the first excitation section in the circumferential direction of the yoke body may be formed in a tapered shape (for example, tapered shape 36c in the embodiment).

[0010] (5) In the rotating electric machine described in any of (1) to (4) above, the second excitation unit is provided with a coil (for example, a coil 65 in the embodiment) around which an auxiliary winding (for example, an auxiliary winding 64 in the embodiment) is wound, and the second excitation unit may be formed in a concave shape (for example, a concave shape 37a in the embodiment) with respect to the outer circumferential surface of the yoke body.

[0011] (6) In the rotating electric machine described in (5) above, the second excitation unit may be formed in a convex shape (for example, the convex shape 37b in the embodiment) with respect to the axial end face of the yoke body.

[0012] (7) In the rotating electric machine described in any of (1) to (6) above, both ends of the second excitation section in the circumferential direction of the yoke body section may be formed in a tapered shape (for example, tapered shape 37c in the embodiment).

[0013] (8) A control system according to an aspect of the present invention (for example, control system 100 in the embodiment) comprises a rotating electric machine as described in any of (1) to (7) above, and a control unit (for example, control unit 90 in the embodiment) that energizes the first excitation unit and the second excitation unit, respectively.

[0014] (9) In the control system described in (8) above, the control unit may control the first excitation unit and the second excitation unit to cause magnetic saturation when changing the direction of the current passing through the coil on which the main winding is wound.

[0015] (10) In the control system described in (8) or (9) above, the control unit may control the first excitation unit and the second excitation unit to increase the magnetic flux when the current passing through the coil on which the main winding is wound does not change abruptly. [Effects of the Invention]

[0016] According to the rotating electric machine described in (1) above of the present invention, a first excitation section is formed on the inner circumference side of the yoke body in the back yoke, and a second excitation section is formed on the outer circumference side of the first excitation section, thereby allowing the magnetic resistance to be controlled by the complementary pole of the back yoke. For example, by magnetically saturating the yoke body, the magnetic resistance can be increased and the inductance can be reduced. Therefore, the current response can be improved.

[0017] According to the rotating electric machine described in (2) above of the present invention, the first excitation section is formed in a concave shape with respect to the inner circumferential surface of the yoke body, thereby preventing the first excitation section from protruding toward the slot side (radially inward).

[0018] According to the rotating electric machine described in (3) above of the present invention, the first excitation section is formed in a convex shape with respect to the axial end face of the yoke body, which provides the following effects. Even when the first excitation section is formed in a concave shape with respect to the inner circumferential surface of the yoke body, a coil with an auxiliary winding can be wound around the first excitation section without changing the cross-sectional area of ​​the yoke body.

[0019] According to the rotating electric machine described in (4) above of the present invention, the tapered shape of both ends of the first excitation section in the circumferential direction of the yoke body provides the following effects: Compared to the case where both ends of the first excitation section are formed in a right-angle shape, the magnetic flux generated in the first excitation section flows more easily in the circumferential direction of the yoke body.

[0020] According to the rotating electric machine described in (5) above of the present invention, the second excitation section is formed in a concave shape with respect to the outer circumferential surface of the yoke body, thereby preventing the second excitation section from protruding on the opposite side (radially outward) from the slot side.

[0021] According to the rotating electrical machine described in (6) above of the present invention, since the second excitation portion is formed in a convex shape with respect to the axial end surface of the yoke body portion, the following effects are obtained. Even when the second excitation portion is formed in a concave shape with respect to the outer circumferential surface of the yoke body portion, a coil around which an auxiliary winding is wound can be wound around the second excitation portion without changing the cross-sectional area of the yoke body portion.

[0022] According to the rotating electrical machine described in (7) above of the present invention, since both end portions of the second excitation portion in the circumferential direction of the yoke body portion are formed in a tapered shape, the following effects are obtained. Compared with a case where both end portions of the second excitation portion are formed in a right-angled shape, magnetic flux generated in the second excitation portion is more likely to flow in the circumferential direction of the yoke body portion.

[0023] According to the control system described in (8) above of the present invention, by including the above rotating electrical machine and a control unit that excites each of the first excitation portion and the second excitation portion, the following effects are obtained. Current response can be improved by the control that excites each of the first excitation portion and the second excitation portion.

[0024] According to the control system described in (9) above of the present invention, when changing the direction of a current passing through a coil around which a main winding is wound, by controlling magnetic saturation to be caused by the first excitation portion and the second excitation portion, the following effects are obtained. Magnetic saturation can be caused by the first excitation portion and the second excitation portion during rising and falling of the current passing through the coil around which the main winding is wound. Due to the occurrence of magnetic saturation, inductance can be reduced, and current response can be improved.

[0025] According to the control system described in (10) above of the present invention, when the current passing through the coil around which the main winding is wound does not change abruptly, by controlling magnetic flux to be increased by the first excitation portion and the second excitation portion, the following effects are obtained. When the current passing through the coil around which the main winding is wound does not change abruptly, magnetic flux can be increased by the first excitation portion and the second excitation portion. For example, during power running or regeneration of the rotating electrical machine, the direction of magnetic flux generated by the coil around which the auxiliary winding is wound can be matched with the direction of magnetic flux generated by the coil around which the main winding is wound. Brief Description of the Drawings

[0026] [Figure 1] FIG. 1 is a diagram illustrating a configuration of a rotating electrical machine according to an embodiment. [Figure 2] FIG. 2 is a diagram illustrating an installation example of a coil according to an embodiment. [Figure 3] FIG. 3 is a diagram illustrating a magnetic flux flow when a current in a main winding according to an embodiment is positive. [Figure 4] FIG. 4 is a diagram illustrating a magnetic flux flow when a current in an auxiliary winding according to an embodiment is positive. [Figure 5] FIG. 5 is a diagram illustrating a configuration of a control system according to an embodiment. [Figure 6] FIG. 6 is a diagram illustrating an installation example of an auxiliary winding according to an embodiment. [Figure 7] FIG. 7 is a diagram illustrating an example of a circuit for a main winding according to an embodiment. [Figure 8] FIG. 8 is a diagram illustrating an example of a circuit for an auxiliary winding according to an embodiment. [Figure 9] FIG. 9 is a schematic diagram of a control method according to an embodiment. [Figure 10] FIG. 10 is a schematic diagram of an operation sequence according to an embodiment. [Figure 11] FIG. 11 is a detailed view of an auxiliary winding according to an embodiment. [Figure 12] FIG. 12 is an explanatory diagram of an auxiliary winding mode according to an embodiment. [Figure 13] FIG. 13 is a flowchart of a control method according to an embodiment. [Figure 14] FIG. 14 is a diagram illustrating an example of control for causing magnetic saturation to occur by a first excitation unit and a second excitation unit according to an embodiment. [Figure 15] FIG. 15 is a diagram illustrating an example of control for increasing magnetic flux by a first excitation unit and a second excitation unit according to an embodiment. Mode for Carrying Out the Invention

[0027] Embodiments of the present invention will be described below with reference to the drawings. In the following description, a switched reluctance motor (SR motor), used as a drive source for vehicles such as automobiles, will be given as an example of a rotating electric machine. In the following description, expressions indicating relative or absolute arrangements such as "parallel," "orthogonal," "center," and "coaxial" will not only mean such arrangements strictly, but will also include states in which the components are relatively displaced with tolerances or angles and distances that allow the same function to be obtained. In the drawings used in the following description, the scale of each component may be changed as appropriate in order to make each component recognizable.

[0028] <Rotating Electric Machinery> Figure 1 shows the configuration of the rotating electric machine 1 according to an embodiment. As shown in Figure 1, the rotating electric machine 1 comprises a rotor 2 having a plurality of salient poles 23, and a stator 3 arranged at a distance from the outer circumferential surface of the rotor 2.

[0029] The rotor 2 comprises a rotating shaft 20 and a rotor core 21. In the following description, the direction along the axis O of the rotating shaft 20 is referred to as the "axial direction," the direction perpendicular to the axis O is referred to as the "radial direction," and the direction around the axis O is referred to as the "circumferential direction."

[0030] The rotating shaft 20 is rotatably supported relative to the stator 3. The rotor core 21 rises radially outward from the outer circumferential surface of the rotating shaft 20. The rotor core 21 is fixed to the rotating shaft 20 by fitting or the like so that their axes overlap. The rotor core 21 is formed into a cylindrical shape by laminating multiple sheets of electrical steel or the like in the axial direction.

[0031] The rotor core 21 comprises a core body portion 22 and a plurality of salient pole portions 23. The core body portion 22 is formed in an annular shape rising radially outward from the rotation axis 20. The plurality of salient pole portions 23 are formed at equal intervals in the circumferential direction. Between adjacent salient pole portions 23 in the circumferential direction, a space 24 is formed in which the circumferential width dimension increases towards the radially outward direction. In the example shown in Figure 1, 10 salient pole portions 23 are formed for one core body portion 22.

[0032] The stator 3 is formed in an annular shape with a space for housing the rotor 2 on its radially inward side. The stator 3 comprises an annularly formed back yoke 30 and a plurality of teeth 31 that protrude radially inward from the back yoke 30 and form slots 32 in which coils 55 on which the main windings 54 are wound are arranged.

[0033] The back yoke 30 is formed in an annular, or more specifically, cylindrical shape along the axis O. Multiple teeth 31 are formed projecting radially inward from the back yoke 30. In the example shown in Figure 1, 12 teeth 31 are formed on one back yoke 30.

[0034] The slot 32 is formed by the inner circumferential surface of the back yoke 30 and the sides of adjacent teeth 31 in the circumferential direction. The radial width dimension of the slot 32 gradually decreases toward the radially inward direction. The slot 32 communicates with the space 24 on the rotor 2 side.

[0035] In the example shown in Figure 1, the rotor 2 has 10 salient poles 23 and the stator 3 has 12 teeth 31, but this is not limited to the above. For example, the number of poles in the salient poles 23 may be 5 poles × N, and the number of poles in the teeth 31 may be 6 poles × N (where "N" is the same natural number). For example, the number of poles in the rotor 2 may be different from or the same as the number of poles in the teeth 31. The combination of the number of poles in the salient poles 23 and the number of poles in the teeth 31 is not limited to the above and can be changed according to the design specifications.

[0036] <Example of coil installation> Figure 2 shows an example of coil installation according to the embodiment. Referring to Figures 1 and 2, the rotating electric machine 1 is equipped with coils 55 on each tooth 31 of the stator 3, each wound with a main winding 54. The main winding 54 passes through adjacent slots 32 in the circumferential direction and is wound around the teeth 31 multiple times to form the coil 55. Two coils (coils 55 wound with the main winding 54) that are adjacent to each other in the circumferential direction are arranged in one slot 32. The main winding 54 wound around the teeth 31 shown in Figure 2 is connected to another tooth 31 or to a motor drive inverter (an example of a component of the main winding circuit 50).

[0037] The back yoke 30 includes a ring-shaped yoke body 35, a first excitation unit 36 ​​formed on the inner circumference of the yoke body 35 that generates a magnetic field, and a second excitation unit 37 formed on the outer circumference of the yoke body 35 that generates a magnetic field. Multiple first excitation units 36 and multiple second excitation units 37 are formed. The multiple excitation units 36 and 37 are each formed at equal intervals in the circumferential direction. The rotating electric machine 1 is equipped with coils 65 around each excitation unit 36 ​​and 37 of the back yoke 30, around which auxiliary windings 64 are wound.

[0038] <1st excitation section> The rotating electric machine 1 includes a coil 65 around which an auxiliary winding 64 is wound in a first excitation unit 36. The first excitation unit 36 ​​is formed in a concave shape 36a relative to the inner circumferential surface of the yoke body 35. The concave shape 36a of the first excitation unit 36 ​​forms a space between the radially inner surface of the first excitation unit 36 ​​(the bottom surface of the concave shape 36a) and the inner circumferential surface of the yoke body 35 in which the coil 65 around which the auxiliary winding 64 is wound is positioned. The concave shape 36a of the first excitation unit 36 ​​is formed so that the coil 65 around which the auxiliary winding 64 is wound does not protrude radially inward from the inner circumferential surface of the yoke body 35.

[0039] The first excitation section 36 is formed in a convex shape 36b relative to the axial end face of the yoke body 35. The convex shape 36b of the first excitation section 36 is formed in a range corresponding to the concave shape 36a of the first excitation section 36 in the circumferential direction of the yoke body 35 (a range that overlaps in the radial direction). The convex shape 36b of the first excitation section 36 is formed on both axial end faces of the yoke body 35. The convex shape 36b of the first excitation section 36 is formed such that the cross-sectional area of ​​the yoke body 35 (the cross-sectional area cut by a plane perpendicular to the circumferential direction) is uniform over the circumferential direction in the range corresponding to the concave shape 36a of the first excitation section 36.

[0040] In the circumferential direction of the yoke body 35, both ends of the first excitation section 36 are formed in a tapered shape 36c. The tapered shape 36c of the first excitation section 36 is formed at both ends of the concave shape 36a and both ends of the convex shape 36b of the first excitation section 36 in the circumferential direction of the yoke body 35. Both ends of the concave shape 36a of the first excitation section 36 are formed in a tapered shape 36c that slopes radially inward as it moves circumferentially outward, from the circumferential outer end of the bottom surface of the concave shape 36a of the first excitation section 36 to the inner circumferential surface of the yoke body 35. Both ends of the convex shape 36b of the first excitation section 36 are formed in a tapered shape 36c that slopes axially inward as it moves circumferentially outward, from the circumferential outer end of the axial outer end surface of the convex shape 36b of the first excitation section 36 to the axial end surface of the yoke body 35.

[0041] <Second excitation section> The rotating electric machine 1 includes a coil 65 around which an auxiliary winding 64 is wound in a second excitation section 37. The second excitation section 37 is formed in a concave shape 37a relative to the outer circumferential surface of the yoke body 35. The concave shape 37a of the second excitation section 37 forms a space between the radially outer surface of the second excitation section 37 (the bottom surface of the concave shape 37a) and the outer circumferential surface of the yoke body 35 in which the coil 65 around which the auxiliary winding 64 is wound is positioned. The concave shape 37a of the second excitation section 37 is formed so that the coil 65 around which the auxiliary winding 64 is wound does not protrude radially outward from the outer circumferential surface of the yoke body 35.

[0042] The second excitation section 37 is formed in a convex shape 37b relative to the axial end face of the yoke body 35. The convex shape 37b of the second excitation section 37 is formed in a range corresponding to the concave shape 37a of the second excitation section 37 in the circumferential direction of the yoke body 35 (a range that overlaps in the radial direction). The convex shape 37b of the second excitation section 37 is formed on both axial end faces of the yoke body 35. The convex shape 37b of the second excitation section 37 is formed such that the cross-sectional area of ​​the yoke body 35 (the cross-sectional area cut by a plane perpendicular to the circumferential direction) is uniform over the circumferential direction in the range corresponding to the concave shape 37a of the second excitation section 37.

[0043] In the circumferential direction of the yoke body 35, both ends of the second excitation section 37 are formed in a tapered shape 37c. The tapered shape 37c of the second excitation section 37 is formed at both ends of the concave shape 37a and both ends of the convex shape 37b of the second excitation section 37 in the circumferential direction of the yoke body 35. Both ends of the concave shape 37a of the second excitation section 37 are formed in a tapered shape 37c that slopes radially outward as it moves circumferentially outward, from the circumferential outer end of the bottom surface of the concave shape 37a of the second excitation section 37 to the outer circumferential surface of the yoke body 35. Both ends of the convex shape 37b of the second excitation section 37 are formed in a tapered shape 37c that slopes axially inward as it moves circumferentially outward, from the circumferential outer end of the axial outer end surface of the convex shape 37b of the second excitation section 37 to the axial end surface of the yoke body 35.

[0044] In the yoke body 35, a space 38 is formed between the first excitation section 36 and the second excitation section 37, where a coil 65 with an auxiliary winding 64 is arranged. The auxiliary winding 64 passes through the space 38 between the radially adjacent first excitation section 36 and the second excitation section 37, and is wound around each excitation section 36, 37 multiple times to form the coil 65. Two radially adjacent coils (coils 65 with auxiliary windings 64) are arranged in one space 38. The auxiliary windings 64 wound around each excitation section 36, 37 shown in Figure 2 are connected to other excitation sections 36, 37 or excitation circuits 91, 92 (examples of components of auxiliary winding circuits 60A1 to 60C2).

[0045] <Relationship between winding pattern and current sign> Figure 3 shows the magnetic flux flow when the current in the main winding 54 according to the embodiment is positive. Figure 4 shows the magnetic flux flow when the current in the auxiliary winding 64 according to the embodiment is positive. In Figures 3 and 4, the rotor 2 in the rotating electric machine 1 is not shown. As shown in Figure 3, when the current in the main winding 54 is positive, a magnetic flux flow (magnetic loop) can be generated in the direction of the arrow LV in the figure. The example in Figure 3 shows the magnetic flux flow that can be generated by any one of the multiple phases (e.g., U phase, V phase, and W phase). Note that the magnetic flux flow that can be generated by the other phases (the other two phases) is the same as the example shown in Figure 3 (except for the location where the magnetic flux flow is generated), so it is not shown.

[0046] As shown in Figure 4, when the current in the auxiliary winding 64 is positive, a magnetic flux flow can be generated in the direction of the arrow MV in the figure. The example in Figure 4 shows the magnetic flux flow that can be generated by any one of the multiple phases (e.g., U phase, V phase, and W phase) (the same phase as in the example shown in Figure 3). Note that the magnetic flux flow that can be generated by other phases (the other two phases) is the same as in the example shown in Figure 4 (except for the location where the magnetic flux flow is generated), so it is not shown.

[0047] Referring to Figures 3 and 4, in this embodiment, the winding pattern is such that the direction of the magnetic flux generated when the current in the main winding 54 is positive (the component along the circumferential direction of the yoke body 35 in the direction of arrow LV shown in Figure 3) coincides with the direction of the magnetic flux generated when the current in the auxiliary winding 64 is positive (the direction of arrow MV shown in Figure 4). This makes it possible to increase the magnetic flux in the direction along the circumferential direction of the yoke body 35. Note that the winding pattern is not limited to the above and can be changed according to the design specifications.

[0048] <Control System> Figure 5 shows the configuration of the control system 100 according to the embodiment. In Figure 5, the rotor 2 in the rotating electric machine 1 is omitted from the illustration. Also, the first excitation circuit 91 and the second excitation circuit 92 are shown as excitation circuits for the coil 65 (auxiliary coil) around which the auxiliary winding 64 is wound. As shown in Figure 5, the control system 100 comprises a rotating electric machine 1 and a control unit 90 that energizes the first excitation unit 36 ​​and the second excitation unit 37, respectively. In the rotating electric machine 1, the coil 55 around which the main winding 54 is wound functions as a torque generating coil.

[0049] In the example shown in Figure 5, the auxiliary windings 64 of each excitation unit 36, 37 for any one of the multiple phases (e.g., U-phase, V-phase, and W-phase) are connected in series to each excitation circuit 91, 92. The configuration for connecting the auxiliary windings 64 of each excitation unit 36, 37 for the other phases (the other two phases) in series to each excitation circuit 91, 92 is the same as the example shown in Figure 5 (except for the connection location), and is therefore omitted from the illustration.

[0050] <Example of auxiliary winding installation> Figure 6 shows an example of the installation of an auxiliary winding 64 according to the embodiment. In Figure 6, the rotor 2 is omitted from the illustration of the rotating electric machine 1. Furthermore, as an example of an auxiliary winding 64 corresponding to multiple phases, an example of an auxiliary winding 64 corresponding to three phases (A phase, B phase, and C phase) is shown. For example, A phase, B phase, and C phase correspond to U phase, V phase, and W phase, respectively.

[0051] In the example shown in Figure 6, in each excitation section of phase A, the first end of each auxiliary winding 64 is the input point for current supply (Ain1, Ain2 shown in Figure 6), and the second end of each auxiliary winding 64 is the output point for current supply (Aout1, Aout2 shown in Figure 6). Similarly, in each excitation section of phase B, the first end of each auxiliary winding 64 is the input point for current supply (Bin1, Bin2 shown in Figure 6), and the second end of each auxiliary winding 64 is the output point for current supply (Bout1, Bout2 shown in Figure 6). Furthermore, in each excitation section of phase C, the first end of each auxiliary winding 64 is the input point for current supply (Cin1, Cin2 shown in Figure 6), and the second end of each auxiliary winding 64 is the output point for current supply (Cout1, Cout2 shown in Figure 6). Furthermore, in each excitation section of each phase, the input points (Ain1, Bin1, Cin1 shown in Figure 6) and output points (Aout1, Bout1, Cout1 shown in Figure 6) are provided on the outer coil 65. In addition, in each excitation section of each phase, the input points (Ain2, Bin2, Cin2 shown in Figure 6) and output points (Aout2, Bout2, Cout2 shown in Figure 6) are provided on the inner coil 65.

[0052] <Main winding circuit> Figure 7 shows an example of the main winding circuit 50 according to the embodiment. As shown in Figure 7, the main winding circuit 50 is configured by connecting a three-phase open winding (main winding 54) to a three-phase asymmetric bridge circuit. A portion of the main winding circuit 50 functions, for example, as a three-phase inverter (power converter) that converts DC to AC.

[0053] The main winding circuit 50 includes a three-phase open winding (main winding 54), a plurality of switching elements 56A1 to 56C2, and a plurality of rectifier elements 57A1 to 57C2 between the high-side reference line 52 (power supply potential line) connected to the positive side of the DC power supply 51 and the low-side reference line 53 (ground line) connected to the negative side of the DC power supply 51. The switching elements 56A1 to 56C2 are transistors such as MOSFETs (Metal Oxide Semiconductor Field Effect Transistors) and IGBTs (Insulated Gate Bipolar Transistors). The rectifier elements 57A1 to 57C2 are diodes, for example.

[0054] The three-phase open winding (main winding 54) comprises the A-phase coil 55A, the B-phase coil 55B, and the C-phase coil 55C. The multiple switching elements 56A1 to 56C2 include the A-phase first switching element 56A1, the A-phase second switching element 56A2, the B-phase first switching element 56B1, the B-phase second switching element 56B2, the C-phase first switching element 56C1, and the C-phase second switching element 56C2. The multiple rectifier elements 57A1 to 57C2 include the A-phase first rectifier element 57A1, the A-phase second rectifier element 57A2, the B-phase first rectifier element 57B1, the B-phase second rectifier element 57B2, the C-phase first rectifier element 57C1, and the C-phase second rectifier element 57C2.

[0055] The first A-phase switching element 56A1 is provided between the first end (left end) of the A-phase coil 55A and the high-side reference line 52. The second A-phase switching element 56A2 is provided between the second end (right end) of the A-phase coil 55A and the low-side reference line 53. The first B-phase switching element 56B1 is located between the first end (left end) of the B-phase coil 55B and the high-side reference line 52. The second B-phase switching element 56B2 is located between the second end (right end) of the B-phase coil 55B and the low-side reference line 53. The first C-phase switching element 56C1 is provided between the first end (left end) of the C-phase coil 55C and the high-side reference line 52. The second C-phase switching element 56C2 is provided between the second end (right end) of the C-phase coil 55C and the low-side reference line 53.

[0056] The first A-phase rectifier element 57A1 is located between the first end (left end) of the A-phase coil 55A and the low-side reference line 53. The first A-phase rectifier element 57A1 has the function of preventing reverse current by allowing current to flow from the low-side reference line 53 towards the first end (left end) of the A-phase coil 55A (one direction). The second A-phase rectifier element 57A2 is located between the second end (right end) of the A-phase coil 55A and the high-side reference line 52. The second A-phase rectifier element 57A2 has the function of preventing reverse current by allowing current to flow from the second end (right end) of the A-phase coil 55A towards the high-side reference line 52 (one direction).

[0057] The B-phase first rectifier element 57B1 is provided between the first end (left end) of the B-phase coil 55B and the low-side reference line 53. The B-phase first rectifier element 57B1 has the function of passing current from the low-side reference line 53 towards the first end (left end) of the B-phase coil 55B (one direction) and preventing reverse current. The B-phase second rectifier element 57B2 is provided between the second end (right end) of the B-phase coil 55B and the high-side reference line 52. The B-phase second rectifier element 57B2 has the function of passing current from the second end (right end) of the B-phase coil 55B towards the high-side reference line 52 (one direction) and preventing reverse current.

[0058] The C-phase first rectifier element 57C1 is provided between the first end (left end) of the C-phase coil 55C and the low-side reference line 53. The C-phase first rectifier element 57C1 has the function of passing current from the low-side reference line 53 towards the first end (left end) of the C-phase coil 55C (one direction) and preventing reverse current. The C-phase second rectifier element 57C2 is provided between the second end (right end) of the C-phase coil 55C and the high-side reference line 52. The C-phase second rectifier element 57C2 has the function of passing current from the second end (right end) of the C-phase coil 55C towards the high-side reference line 52 (one direction) and preventing reverse current.

[0059] <Auxiliary winding circuit> Figure 8 shows an example of an auxiliary winding circuit 60A1 to 60C2 according to the embodiment. As shown in Figure 8, the auxiliary winding circuits 60A1 to 60C2 are configured by connecting auxiliary windings 64 corresponding to each of the three phases to an H-bridge circuit. A portion of the auxiliary winding circuits 60A1 to 60C2 functions, for example, as an inverter (power converter) that converts DC to AC.

[0060] The auxiliary winding circuits 60A1 to 60C2 include auxiliary windings 64 corresponding to each phase and a plurality of switching elements 66 between the high-side reference line 62 (power supply potential line) connected to the positive side of the DC power supply 61 and the low-side reference line 63 (ground line) connected to the negative side of the DC power supply 61. The switching elements 66 are transistors such as MOSFETs (Metal Oxide Semiconductor Field Effect Transistors) and IGBTs (Insulated Gate Bipolar Transistors).

[0061] In the example shown in Figure 8, we see the A-phase first auxiliary winding circuit 60A1, the A-phase second auxiliary winding circuit 60A2, the B-phase first auxiliary winding circuit 60B1, the B-phase second auxiliary winding circuit 60B2, the C-phase first auxiliary winding circuit 60C1, and the C-phase second auxiliary winding circuit 60C2. Below, we will describe the A-phase first auxiliary winding circuit 60A1. Note that the other auxiliary winding circuits 60A2 to 60C2 are the same as the A-phase first auxiliary winding circuit 60A1 (excluding the corresponding auxiliary winding 64 and corresponding phase), so detailed explanations will be omitted.

[0062] The A-phase first auxiliary winding circuit 60A1 includes a first auxiliary winding 64 corresponding to the A-phase and a plurality of switching elements 66A1 to 66A4, between a high-side reference line 62 (power potential line) connected to the positive side of the DC power supply 61 and a low-side reference line 63 (ground line) connected to the negative side of the DC power supply 61.

[0063] The first auxiliary winding 64 constitutes the A-phase input coil (coil 65 on the Ain1 side shown in Figure 8) and the A-phase output coil (coil 65 on the Aout1 side shown in Figure 8). The multiple switching elements 66A1 to 66A4 include the first A-phase switching element 66A1, the second A-phase switching element 66A2, the third A-phase switching element 66A3, and the fourth A-phase switching element 66A4.

[0064] The first A-phase switching element 66A1 is located between the first end (left end) of the A-phase input coil (coil 65 on the Ain1 side shown in Figure 8) and the high-side reference line 62. The second A-phase switching element 66A2 is located between the first end (left end) of the A-phase input coil (coil 65 on the Ain1 side shown in Figure 8) and the low-side reference line 63. The third A-phase switching element 66A3 is located between the second end (right end) of the A-phase output coil (coil 65 on the Aout1 side shown in Figure 8) and the high-side reference line 62. The fourth A-phase switching element 66A4 is located between the second end (right end) of the A-phase output coil (coil 65 on the Aout1 side shown in Figure 8) and the low-side reference line 63.

[0065] <Overview of Control Method> Figure 9 is a schematic diagram of the control method according to the embodiment. Referring to Figures 7 to 9, the control unit 90 (see Figure 5) performs management control based on predetermined operating conditions. These predetermined operating conditions are, for example, the conditions for normal mode, magnetic saturation mode, powering / regenerative flux increase mode, etc. As part of the management control, the control unit 90 issues a main winding current command (a command to supply current to the main winding 54) and an auxiliary winding current command (a command to supply current to the auxiliary winding 64).

[0066] The control unit 90 performs main winding current control (control of the current passing through the main winding 54) as a main winding current command. As main winding current control, the control unit 90 sends SW (switch) signals to each switching element 56A1 to 56C2 of the main winding circuit 50. The control unit 90 sends SW signals to, for example, six arms (switching elements enclosed by dashed lines in the main winding circuit shown in Figure 9).

[0067] The control unit 90 selects either the magnetic saturation mode or the powering / regenerative flux increase mode as the auxiliary winding current command. In the magnetic saturation mode, the control unit 90 sets the sign of the current command i1 passing through the first auxiliary winding 64 (corresponding to the auxiliary winding 64 connected to the first excitation circuit 91) and the current command i2 passing through the second auxiliary winding 64 (corresponding to the auxiliary winding 64 connected to the second excitation circuit 92) to be different. In the magnetic saturation mode, the control unit 90 sets the current command i1 passing through the first auxiliary winding 64 to be positive (i1>0) and the current command i2 passing through the second auxiliary winding 64 to be negative (i2<0). Alternatively, in the magnetic saturation mode, the control unit 90 sets the current command i1 passing through the first auxiliary winding 64 to be negative (i1<0) and the current command i2 passing through the second auxiliary winding 64 to be positive (i2>0).

[0068] In the powering / regenerative flux increase mode, the control unit 90 sets the sign of the current command i1 passing through the first auxiliary winding 64 and the sign of the current command i2 passing through the second auxiliary winding 64 to be the same. In the powering / regenerative flux increase mode, the control unit 90 sets the current command i1 passing through the first auxiliary winding 64 to be positive (i1>0) and the current command i2 passing through the second auxiliary winding 64 to be positive (i2>0).

[0069] The control unit 90 controls the auxiliary winding current (controls the current passing through the auxiliary winding 64) based on current commands i1 and i2. As auxiliary winding current control, the control unit 90 sends SW (switch) signals to each switching element 56A1 to 56C2 of the auxiliary winding circuit 60A1 to 60C2. The control unit 90 sends SW signals to, for example, 12 arms (switching elements enclosed by dashed lines in the auxiliary winding circuit shown in Figure 9).

[0070] <Overview of Operation Sequence> Figure 10 is a schematic diagram of the operation sequence according to the embodiment. In Figure 10, the vertical axis shows, from top to bottom, target torque, main winding current, auxiliary winding mode, and auxiliary winding current, while the horizontal axis shows time. As shown in Figure 10, the control unit 90 controls the main winding current (the current passing through the main winding 54) based on the target torque. The control unit 90 controls the main winding current not only based on the target torque but also on the timing of the energizing phase switching.

[0071] <Details of auxiliary windings> Figure 11 is a detailed view of the auxiliary winding 64 according to the embodiment. As shown in Figure 11, magnetic saturation can be generated by reversing the current signs of the first auxiliary winding 64 and the second auxiliary winding 64. In the example in Figure 11, the current through the first auxiliary winding 64 is positive (ix1>0), and the current through the second auxiliary winding 64 is negative (ix2<0). Let ixn = iun, ivn, iwn. n is a natural number (for example, 1 or 2), and u, v, w correspond to the respective phases (for example, phase A, phase B, phase C).

[0072] In detail, increasing the current flowing through the main winding 54 increases the strength of the magnetic field, which in turn increases the magnetic flux density. However, it eventually saturates, reaching a state where the magnetic flux density no longer increases (magnetic saturation). When magnetic saturation occurs, the inductance decreases. To improve the current response, it is necessary to reduce the inductance, thus requiring the induction of magnetic saturation.

[0073] <Auxiliary winding mode> Figure 12 is an explanatory diagram of the auxiliary winding mode according to the embodiment. As shown in Figure 12, the auxiliary winding modes include Mode 0, Mode 1, Mode 2, and Mode 3. Mode 0 is the non-energized state mode. Mode 1 is the mode for generating magnetic saturation. Mode 2 is the mode for increasing the power flux. Mode 3 is the mode for increasing the regenerative flux.

[0074] When auxiliary winding mode 0, the control unit 90 sets the current command ix1 for the first auxiliary winding 64 to zero (ix1=0) and the current command ix2 for the second auxiliary winding 64 to zero (ix2=0). In auxiliary winding mode 1, the control unit 90 sets the current command ix1 for the first auxiliary winding 64 to be positive (ix1>0) and the current command ix2 for the second auxiliary winding 64 to be negative (ix2<0). Alternatively, in auxiliary winding mode 1, the control unit 90 sets the current command ix1 for the first auxiliary winding 64 to be negative (ix1<0) and the current command ix2 for the second auxiliary winding 64 to be positive (ix2>0). In the case of auxiliary winding modes 2 and 3, the control unit 90 sets the current command ix1 for the first auxiliary winding 64 to be positive (ix1>0) and the current command ix2 for the second auxiliary winding 64 to be positive (ix2>0).

[0075] <Control of the first and second excitation sections> Referring to Figures 10 to 12, the control unit 90 controls the first excitation unit 36 ​​and the second excitation unit 37 to cause magnetic saturation when changing the direction of the current passing through the coil 55 on which the main winding 54 is wound.

[0076] In detail, the control unit 90 sets the current command ix1 for the first auxiliary winding 64 wound around each excitation unit and the current command ix2 for the second auxiliary winding 64 wound around each excitation unit to opposite signs during transients of the main winding current (during the rising and falling of the current passing through the coil 55 around which the main winding 54 is wound). During the rising of the current, this corresponds to the timing when the current value passing through the main winding 54 switches from a constant state (zero in the example of Figure 10) to a positive state. During the falling of the current, this corresponds to the timing when the current value passing through the main winding 54 switches from a constant state (a positive value in the example of Figure 10) to a negative state. In the example of Figure 10, during transients of the main winding current, the control unit 90 sets the current command ix1 for the first auxiliary winding 64 wound around each excitation unit to positive (ix1>0) and the current command ix2 for the second auxiliary winding 64 to negative (ix2<0).

[0077] Furthermore, the control unit 90 controls the magnetic flux to increase using the first excitation unit 36 ​​and the second excitation unit 37 when the current passing through the coil 55 on which the main winding 54 is wound does not change rapidly. For example, the control unit 90 may control the magnetic flux to increase using the first excitation unit 36 ​​and the second excitation unit 37 when the current passing through the coil 55 on which the main winding 54 is wound is constant.

[0078] In detail, when the main winding current is steady, the control unit 90 sets the current command ix1 for the first auxiliary winding 64 wound around each excitation unit and the current command ix2 for the second auxiliary winding 64 to have the same sign. In the example in Figure 10, when the main winding current is steady, the control unit 90 sets the current command ix1 for the first auxiliary winding 64 wound around each excitation unit and the current command ix2 for the second auxiliary winding 64 to be positive (ix1>0 and ix2>0).

[0079] <Control Method Flow> Figure 13 is a flowchart showing the control method according to the embodiment. As shown in Figure 13, the control method includes acquiring the target torque (first step S1), calculating the distribution of main winding and auxiliary winding currents (second step S2), acquiring the main winding target current (third step S3), acquiring the auxiliary winding drive mode (fourth step S4), acquiring the auxiliary winding target current (fifth step S5), controlling the main winding current (sixth step S6), controlling the auxiliary winding current (seventh step S7), issuing a main winding PWM command (eighth step S8), and issuing an auxiliary winding PWM command (ninth step S9).

[0080] In the first step S1, the control unit 90 obtains the target torque (see Figure 10) from the higher-level controller (not shown). After the first step S1, the process proceeds to the second step S2.

[0081] In the second step S2, the control unit 90 obtains the current ratio between the main winding 54 and the auxiliary winding 64 from the operating point (for example, the magnitude of the target torque or the rotational speed of the motor). After the second step S2, the process proceeds to the third step S3.

[0082] In the third step S3, the control unit 90 obtains the target current for each phase's main winding 54 based on the target torque and the current ratio obtained in the second step S2. After the third step S3, the process proceeds to the fourth step S4.

[0083] In the fourth step S4, the control unit 90 determines the drive mode of each phase's auxiliary winding 64 according to the transient / steady state of the main winding current. The transient state of the main winding current corresponds to a change in the direction of the current passing through the coil 55 around which the main winding 54 is wound (rising and falling edges). The steady state of the main winding current corresponds to a situation where the current passing through the coil 55 around which the main winding 54 is wound does not change abruptly (for example, it is constant).

[0084] In the fourth step S4, the control unit 90 selects the magnetic saturation mode (high response) when it is necessary to improve the current response (when the main winding current is transient). In the fourth step S4, the control unit 90 selects the power / regeneration mode (high torque) when it is in a steady state (when the main winding current is steady). After the fourth step S4, the system proceeds to the fifth step S5.

[0085] In the fifth step S5, the control unit 90 obtains the target current (current value) of the auxiliary winding 64 for each phase based on the target torque, the current ratio obtained in the second step S2, and the transient conditions. After the fifth step S5, the process proceeds to the sixth step S6.

[0086] In the sixth step S6, the control unit 90 receives feedback on the current values ​​of the main windings 54 for each phase and calculates the target voltage to be output by the inverter (for example, the main winding circuit 50). After the sixth step S6, the process proceeds to the seventh step S7.

[0087] In step 7, S7, the control unit 90 receives feedback on the current values ​​of the auxiliary windings 64 for each phase and calculates the target voltage to be output by the inverter (for example, the auxiliary winding circuits 60A1 to 60C2). After step 7, S7, the process proceeds to step 8, S8.

[0088] In step 8, S8, the control unit 90 converts the target voltage of each phase's main winding 54 into PWM (Pulse Width Modulation) and commands the inverter (for example, the main winding circuit 50). After step 8, S8, the process proceeds to step 9, S9.

[0089] In step 9, S9, the control unit 90 converts the target voltage of each phase's auxiliary winding 64 into PWM (pulse width modulation) and commands the inverter (for example, the auxiliary winding circuits 60A1 to 60C2). This concludes the control method flow.

[0090] <An example of controlling the first and second excitation sections to induce magnetic saturation> Figure 14 shows an example of controlling magnetic saturation to occur using the first excitation unit 36 ​​and the second excitation unit 37 according to the embodiment. For convenience, in Figure 14, the circumferential direction of the rotating electric machine 1 is shown aligned with the left-right direction. In the example in Figure 14, the flow of magnetic flux that can be generated by any one of the multiple phases (for example, U phase, V phase, and W phase) is shown. Note that the flow of magnetic flux that can be generated by the other phases (the other two phases) is the same as in the example shown in Figure 14 (except for the location where the magnetic flux flow occurs), so it is not shown.

[0091] As shown in Figure 14, when the control unit 90 controls the first excitation unit 36 ​​and the second excitation unit 37 to generate magnetic saturation, it controls the magnetic flux flow to be generated in the direction of the arrow in the figure. When the control unit 90 controls the first excitation unit 36 ​​and the second excitation unit 37 to generate magnetic saturation, it controls the magnetic flux flow of the first excitation unit 36 ​​and the magnetic flux flow of the second excitation unit 37 to be in opposite directions (opposite directions in the circumferential direction of the yoke body 35). By generating magnetic flux in the direction of the arrow in the figure, magnetic saturation can be generated and the inductance can be reduced.

[0092] <An example of controlling the magnetic flux to increase using the first and second excitation sections> Figure 15 shows an example of controlling the magnetic flux to increase using the first excitation unit 36 ​​and the second excitation unit 37 according to the embodiment. In Figure 15, for convenience, the circumferential direction of the rotating electric machine 1 is shown aligned with the left-right direction. In the example in Figure 15, the flow of magnetic flux that can be generated by any one of the multiple phases (for example, U phase, V phase, and W phase) is shown. Note that the flow of magnetic flux that can be generated by the other phases (the other two phases) is the same as in the example shown in Figure 15 (except for the location where the magnetic flux flow is generated), so it is not shown.

[0093] As shown in Figure 15, when the control unit 90 controls the first excitation unit 36 ​​and the second excitation unit 37 to increase the magnetic flux, it controls the generation of magnetic flux flow in the direction of the arrow in the figure. When the control unit 90 controls the first excitation unit 36 ​​and the second excitation unit 37 to increase the magnetic flux, it controls the magnetic flux flow from the first excitation unit 36 ​​and the magnetic flux flow from the second excitation unit 37 to be in the same direction (the same direction in the circumferential direction of the yoke body 35). The magnetic flux flow in the direction of the arrow in the figure increases the magnetic flux in the direction along the circumferential direction of the yoke body 35 (the left-right direction in Figure 15), thereby increasing the torque.

[0094] Thus, according to this embodiment, the control unit 90 controls the positive and negative polarity of the current passing through each auxiliary winding 64, thereby enabling the use of magnetic saturation (inductance reduction) (see Figure 14) and magnetic flux increase (torque increase) (see Figure 15). Furthermore, in this embodiment, there is a portion of the back yoke 30 where the cross-sectional area is reduced (the space 38 in the yoke body 35 where the coil 65 with the auxiliary winding 64 wound between the first excitation unit 36 ​​and the second excitation unit 37 is arranged). The cross-sectional area of ​​the portion with reduced cross-sectional area can be increased by a three-dimensional structure (for example, a convex shape 36b, 37b). Furthermore, in this embodiment, in the magnetic saturation mode, the magnetic flux of the energized phase other than the saturation phase may decrease. In this case, the reduction in magnetic flux can be suppressed by combining it with a winding pattern with a short magnetic path (see Figure 1).

[0095] <Effects and Effects> As described above, the rotating electric machine 1 of the above embodiment comprises a rotor 2 having a plurality of salient poles 23, and a stator 3 arranged at a distance from the outer circumferential surface of the rotor 2. The stator 3 comprises an annularly formed back yoke 30, and a plurality of teeth 31 that protrude radially inward from the back yoke 30 and form slots 32 in which coils 55 on which main windings 54 are wound are arranged. The back yoke 30 comprises an annularly formed yoke body portion 35, a first excitation portion 36 formed on the inner circumferential side of the yoke body portion 35 and generating a magnetic field, and a second excitation portion 37 formed on the outer circumferential side of the yoke body portion 35 and generating a magnetic field. In this configuration, a first excitation section 36 is formed on the inner circumference side of the yoke body 35 in the back yoke 30, and a second excitation section 37 is formed on the outer circumference side of the first excitation section 36. This allows the magnetic resistance to be controlled by the complementary poles of the back yoke 30. For example, by magnetically saturating the yoke body 35, the magnetic resistance can be increased and the inductance can be reduced. Therefore, the current response can be improved. For example, by improving the current response, the response of the torque current (the current that generates torque) can be improved, thereby improving the torque response. Furthermore, negative torque caused by the tail current can be rapidly reduced. Note that the tail current refers to the current flowing during the latter half of the IGBT's turn-off period (tail phase).

[0096] In the above embodiment, the first excitation unit 36 ​​is provided with a coil 65 around which an auxiliary winding 64 is wound. The first excitation unit 36 ​​is formed in a concave shape 36a relative to the inner circumferential surface of the yoke body 35. This configuration prevents the first excitation unit 36 ​​from protruding toward the slot 32 side (radially inward).

[0097] In the above embodiment, the first excitation unit 36 ​​is formed in a convex shape 36b with respect to the axial end face of the yoke body 35. With this configuration, even if the first excitation unit 36 ​​is formed in a concave shape 36a relative to the inner circumferential surface of the yoke body 35, the coil 65 with the auxiliary winding 64 wound around the first excitation unit 36 ​​can be wound around the first excitation unit 36 ​​without changing the cross-sectional area of ​​the yoke body 35.

[0098] In the above embodiment, both ends of the first excitation section 36 are formed in a tapered shape 36c in the circumferential direction of the yoke body 35. With this configuration, compared to the case where both ends of the first excitation unit 36 ​​are formed in a right-angle shape, the magnetic flux generated in the first excitation unit 36 ​​flows more easily in the circumferential direction of the yoke body 35.

[0099] In the above embodiment, the second excitation unit 37 is provided with a coil 65 around which an auxiliary winding 64 is wound. The second excitation unit 37 is formed in a concave shape 37a relative to the outer circumferential surface of the yoke body 35. This configuration prevents the second excitation unit 37 from protruding to the opposite side (radially outward) from the slot 32 side.

[0100] In the above embodiment, the second excitation unit 37 is formed in a convex shape 37b with respect to the axial end face of the yoke body 35. With this configuration, even if the second excitation unit 37 is formed in a concave shape 37a relative to the outer circumferential surface of the yoke body 35, the coil 65 with the auxiliary winding 64 wound around the second excitation unit 37 can be wound around the second excitation unit 37 without changing the cross-sectional area of ​​the yoke body 35.

[0101] In the above embodiment, both ends of the second excitation section 37 are formed in a tapered shape 37c in the circumferential direction of the yoke body 35. With this configuration, compared to the case where both ends of the second excitation section 37 are formed in a right-angle shape, the magnetic flux generated in the second excitation section 37 flows more easily in the circumferential direction of the yoke body section 35.

[0102] In the above embodiment, the control system 100 comprises the rotating electric machine 1 and a control unit 90 that energizes the first excitation unit 36 ​​and the second excitation unit 37, respectively. With this configuration, the current response can be improved by controlling the excitation of the first excitation unit 36 ​​and the second excitation unit 37, respectively.

[0103] In the above embodiment, when the control unit 90 changes the direction of the current passing through the coil 55 on which the main winding 54 is wound, it controls the first excitation unit 36 ​​and the second excitation unit 37 to cause magnetic saturation. With this configuration, magnetic saturation can be generated by the first excitation unit 36 ​​and the second excitation unit 37 during the rising and falling of the current flowing through the coil 55 on which the main winding 54 is wound. By generating magnetic saturation, the inductance can be reduced and the current response can be improved.

[0104] In the above embodiment, the control unit 90 controls the magnetic flux to increase using the first excitation unit 36 ​​and the second excitation unit 37 when the current passing through the coil 55 on which the main winding 54 is wound does not change rapidly. With this configuration, when the current passing through the coil 55 around which the main winding 54 is wound does not change rapidly, the magnetic flux can be increased by the first excitation unit 36 ​​and the second excitation unit 37. For example, during powering or regeneration of the rotating electric machine 1, the direction of the magnetic flux generated in the coil 65 around which the auxiliary winding 64 is wound can be aligned with the direction of the magnetic flux generated in the coil 55 around which the main winding 54 is wound.

[0105] <Variation> In the above embodiment, an example was described in which the first excitation section is equipped with a coil around which an auxiliary winding is wound, and the first excitation section is formed in a concave shape relative to the inner circumferential surface of the yoke body, but the invention is not limited to this. For example, the first excitation section may be formed in a convex shape relative to the inner circumferential surface of the yoke body. For example, the first excitation section may be formed in a shape that follows the inner circumferential surface of the yoke body. The shape of the first excitation section relative to the inner circumferential surface of the yoke can be changed according to the design specifications.

[0106] In the above embodiment, the first excitation section was described as being formed in a convex shape relative to the axial end face of the yoke body, but it is not limited to this. For example, the first excitation section may be formed in a concave shape relative to the axial end face of the yoke body. For example, the first excitation section may be formed in a shape that follows the axial end face of the yoke body. The shape of the first excitation section relative to the axial end face of the yoke body can be changed according to the design specifications.

[0107] In the above embodiment, an example was given in which both ends of the first excitation section are formed in a tapered shape in the circumferential direction of the yoke body, but this is not limited to this. For example, both ends of the first excitation section may be formed in a right-angle shape in the circumferential direction of the yoke body. The shape of both ends of the first excitation section in the circumferential direction of the yoke body can be changed according to the design specifications.

[0108] In the above embodiment, an example was described in which the second excitation section is equipped with a coil around which an auxiliary winding is wound, and the second excitation section is formed in a concave shape relative to the outer circumferential surface of the yoke body; however, the embodiment is not limited to this. For example, the second excitation section may be formed in a convex shape relative to the outer circumferential surface of the yoke body. For example, the second excitation section may be formed in a shape that follows the outer circumferential surface of the yoke body. The shape of the second excitation section relative to the outer circumferential surface of the yoke can be changed according to the design specifications.

[0109] In the above embodiment, the second excitation section was described as being formed in a convex shape relative to the axial end face of the yoke body, but it is not limited to this. For example, the second excitation section may be formed in a concave shape relative to the axial end face of the yoke body. For example, the second excitation section may be formed in a shape that follows the axial end face of the yoke body. The shape of the second excitation section relative to the axial end face of the yoke body can be changed according to the design specifications.

[0110] In the above embodiment, an example was given in which both ends of the second excitation section in the circumferential direction of the yoke body are formed in a tapered shape, but this is not limited to this. For example, both ends of the second excitation section in the circumferential direction of the yoke body may be formed in a right-angle shape. The shape of both ends of the second excitation section in the circumferential direction of the yoke body can be changed according to the design specifications.

[0111] In the above embodiment, the control system was described as comprising the rotating electric machine and a control unit for exciting the first excitation unit and the second excitation unit, respectively, but it is not limited to this. For example, the rotating electric machine may be provided with a control unit for exciting the first excitation unit and the second excitation unit, respectively. The configuration of the control unit can be changed according to the design specifications.

[0112] In the above embodiment, an example was given in which the control unit controls the first excitation unit and the second excitation unit to cause magnetic saturation when changing the direction of the current flowing through the coil around the main winding, but the invention is not limited to this. For example, the control unit does not need to control the first excitation unit and the second excitation unit to cause magnetic saturation when changing the direction of the current flowing through the coil around the main winding. The manner in which the first excitation unit and the second excitation unit are controlled when changing the direction of the current flowing through the coil around the main winding can be changed according to the design specifications.

[0113] In the above embodiment, an example was given in which the control unit controls the magnetic flux to increase using the first excitation unit and the second excitation unit when the current passing through the coil around the main winding does not change rapidly, but the invention is not limited to this example. For example, the control unit does not need to control the magnetic flux to increase using the first excitation unit and the second excitation unit when the current passing through the coil around the main winding does not change rapidly. The manner in which the first excitation unit and the second excitation unit are controlled when the current passing through the coil around the main winding does not change rapidly can be changed according to the design specifications.

[0114] In the above embodiment, the rotating electric machine was described as being driven by three phases: U-phase, V-phase, and W-phase, but it is not limited to this. For example, the rotating electric machine may be a single-phase type, or a type driven by multiple phases other than three phases. The mode of driving the rotating electric machine can be changed according to the design specifications.

[0115] In the above embodiment, an SR motor for vehicle drive was given as an example of a rotating electric machine, but it is not limited to this. For example, the rotating electric machine may be applied to motors other than those for vehicle drive. The application target of the rotating electric machine can be changed according to the design specifications.

[0116] Furthermore, the entirety or a part thereof of the functions of each part of the control system of the rotating electric machine in the above embodiment may be realized by recording a program for realizing these functions on a computer-readable recording medium, having a computer system read the program recorded on this recording medium, and executing it. The term "computer system" here includes hardware such as an operating system and peripheral devices. Furthermore, "computer-readable recording media" refers to portable media such as flexible disks, magneto-optical disks, ROMs, and CD-ROMs, as well as storage units such as hard disks built into computer systems. In addition, "computer-readable recording media" may also include those that dynamically hold programs for a short period of time, such as communication lines used when transmitting programs over networks such as the Internet or communication lines such as telephone lines, and those that hold programs for a certain period of time, such as volatile memory inside computer systems that act as servers or clients in such cases. Moreover, the above-mentioned programs may be for the purpose of realizing some of the functions described above, and may also be programs that can realize the aforementioned functions in combination with programs already recorded in the computer system.

[0117] Although embodiments for carrying out the present invention have been described above using examples, the present invention is not limited in any way to these embodiments, and various modifications and substitutions can be made without departing from the spirit of the present invention. [Explanation of Symbols]

[0118] 1. Rotating electric machine 2 rotors 3 stata 23 Salient pole part 30 Back Yoke 31 Teeth 32 slots 35 Yoke main body 36 1st excitation section 36a concave shape 36b Convex shape 36c tapered shape 37 2nd excitation section 37a concave shape 37b Convex shape 37c tapered shape 54 Main winding 55 coils 64 Auxiliary winding 65 coils 90 Control Unit 100 control systems

Claims

1. A rotor having multiple salient poles, The rotor comprises a stator positioned at a distance from its outer circumferential surface, The stator is, A ring-shaped back yoke, The back yoke comprises a plurality of teeth that protrude radially inward and form slots in which coils with main windings are arranged, The aforementioned back yoke is The yoke body is formed in a ring shape, A first excitation section is formed on the inner circumference side of the yoke body and generates a magnetic field, The yoke body portion includes a second excitation portion formed on the outer circumference side of the first excitation portion, which generates a magnetic field. Rotating electric machine.

2. The first excitation section is equipped with a coil around which an auxiliary winding is wound, The first excitation section is formed in a concave shape relative to the inner circumferential surface of the yoke body. The rotating electric machine according to claim 1.

3. The first excitation section is formed in a convex shape with respect to the axial end face of the yoke body. The rotating electric machine according to claim 2.

4. In the circumferential direction of the yoke body, both ends of the first excitation section are formed in a tapered shape. A rotating electric machine according to any one of claims 1 to 3.

5. The second excitation section is equipped with a coil around which an auxiliary winding is wound, The second excitation section is formed in a concave shape relative to the outer circumferential surface of the yoke body. A rotating electric machine according to any one of claims 1 to 3.

6. The second excitation section is formed in a convex shape with respect to the axial end face of the yoke body. The rotating electric machine according to claim 5.

7. In the circumferential direction of the yoke body, both ends of the second excitation section are formed in a tapered shape. A rotating electric machine according to any one of claims 1 to 3.

8. A rotating electric machine according to any one of claims 1 to 3, The system comprises a control unit that energizes the first excitation unit and the second excitation unit, Control system.

9. The control unit controls the first excitation unit and the second excitation unit to cause magnetic saturation when changing the direction of the current passing through the coil on which the main winding is wound. The control system according to claim 8.

10. The control unit controls the magnetic flux to increase using the first excitation unit and the second excitation unit when the current passing through the coil on which the main winding is wound does not change abruptly. The control system according to claim 8.

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