Variable magnetic flux magnet module and rotating electric machine

Abstract

To provide a variable flux magnet module that makes it possible to reduce individual differences.SOLUTION: A variable flux magnet module includes a variable flux magnet and one or more coils arranged at least on a first face of the faces that the variable flux magnet has.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a variable magnetic flux magnet module and a rotating electric machine. [Background technology]

[0002] Research and development is ongoing into technologies for improving the efficiency of rotating electrical machines.

[0003] In this regard, a rotating electric machine is known that includes a rotor and a stator having a variable flux magnet module including a variable flux magnet and a magnetizing coil made of a conductor wound around the side of the variable flux magnet (see Non-Patent Document 1). Here, a variable flux magnet is a magnet that can be demagnetized or inmagnetized by applying a magnetic field, and is sometimes called a variable magnet. In this specification, demagnetization means weakening the magnetic force, i.e., reducing the magnetic force. Also, in this specification, magnetization means strengthening the magnetic force, i.e., increasing the magnetic force. Also, in this specification, changing the magnetic force will be described as transmagnetization. [Prior art documents] [Patent documents]

[0004] [Non-Patent Document 1] Y. Yamada and K. Akatsu, "A new motor with stator magnet using the magnetization reversal technique", 2016 XXII International Conference on Electrical Machines (ICEM), Institute of Electrical and Electronics Engineers (IEEE). Summary of the Invention [Problem to be solved by the invention]

[0005] In a rotating electric machine such as that described in Non-Patent Document 1, when the rotor rotation speed exceeds a predetermined threshold, a current is passed through the magnetizing coil of the variable flux magnet module included in the rotating electric machine to demagnetize the variable flux magnet, thereby achieving field weakening. This improves the efficiency of the rotating electric machine. However, the strength of the magnetic field generated by the magnetizing coil often differs between the center of the magnetizing coil and the outer edge of the magnetizing coil. This difference in magnetic field strength increases individual differences between the variable flux magnet modules and, as a result, increases individual differences between the rotating electric machine, which is undesirable.

[0006] The present disclosure has been made in consideration of the above circumstances, and an object of the present disclosure is to provide a variable magnetic flux magnet module and a rotating electric machine that can reduce individual differences. [Means for solving the problem]

[0007] One aspect of the present disclosure is a variable flux magnet module including a variable flux magnet and one or more coils arranged on at least a first surface of the surfaces of the variable flux magnet. [Effects of the Invention]

[0008] According to the present disclosure, individual differences can be reduced. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram illustrating an example of the configuration of a rotating electrical machine control system 1. FIG. [Figure 2] FIG. 10 is a perspective view showing an example of the configuration of a variable magnetic flux magnet module VMM. [Figure 3] FIG. 3 is a perspective view of the variable magnetic flux magnet module VMM shown in FIG. 2 as seen from another direction. [Figure 4] FIG. 10 is a perspective view showing a first modified example of the configuration of the variable magnetic flux magnet module VMM. [Figure 5] FIG. 10 is a perspective view showing a second modified example of the configuration of the variable magnetic flux magnet module VMM. [Figure 6] FIG. 10 is a perspective view showing a third modified example of the configuration of the variable magnetic flux magnet module VMM. [Figure 7] FIG. 10 is a perspective view showing a fourth modified example of the configuration of the variable magnetic flux magnet module VMM. [Figure 8] FIG. 10 is a perspective view showing a fifth modified example of the configuration of the variable magnetic flux magnet module VMM. [Figure 9] FIG. 10 is a diagram showing an example of a state in which a variable magnetic flux magnet VM is housed in a recess CC of a magnetic body MB together with 24 magnetizing coils C arranged on a first surface M1. [Figure 10] 10 is a diagram showing an example of a state in which a variable magnetic flux magnet VM is taken out from a recess CC of the magnetic body MB shown in FIG. [Figure 11] 10 is a diagram showing an example of a flow of processing in which the control device 20 controls the variable magnetic flux magnet module VMM. FIG. [Figure 12] FIG. 10 is a diagram showing a first modification of the flow of processing in which the control device 20 controls the variable magnetic flux magnet module VMM. [Figure 13] 10 is a timing chart showing an example of temporal changes in the magnitude of the current that the control device 20 applies to the variable magnetic flux magnet module VMM by repeating the processing of steps S230 to S240. [Figure 14] FIG. 10 is a diagram showing a second modification of the flow of processing in which the control device 20 controls the variable magnetic flux magnet module VMM. [Figure 15] 10 is a timing chart showing an example of temporal changes in the magnitude of the current that the control device 20 applies to the variable magnetic flux magnet module VMM by repeating the processing of steps S330 to S340. [Figure 16] FIG. 10 is a diagram showing a third modification of the flow of processing in which the control device 20 controls the variable magnetic flux magnet module VMM. DETAILED DESCRIPTION OF THE INVENTION

[0010] <Embodiment> Hereinafter, embodiments of the technology according to the present disclosure will be described with reference to the drawings. Herein, a coil in the embodiments refers to a conductor wound around at least one of a certain region and a certain object, and does not include a conductor as a lead wire connecting these conductors to another circuit. However, the coil may also be configured to include a conductor as a lead wire connecting the conductor wound around at least one of a certain region and a certain object to another circuit.

[0011] <Configuration of rotating electrical machine control system> The configuration of the rotating electrical machine control system 1 will be described below with reference to Fig. 1. Fig. 1 is a diagram showing an example of the configuration of the rotating electrical machine control system 1.

[0012] The rotating electrical machine control system 1 includes a rotating electrical machine 10 and a control device 20.

[0013] The rotating electric machine 10 is a motor provided to rotate a rotating body in a device that changes the rotation speed of the rotating body in response to a control signal. Examples of such devices include, but are not limited to, motors that drive electric vehicles and motors that drive washing machines.

[0014] In the following, a case where the rotating electrical machine 10 is a three-phase brushless motor will be described as an example. Note that the rotating electrical machine 10 may be a motor of another type instead of a three-phase brushless motor.

[0015] The rotating electric machine 10 includes a rotor 11, a stator 12, and N variable magnetic flux magnet modules VMM. In FIG. 1 , to simplify the drawing, components of the rotating electric machine 10 other than the rotor 11 and the stator 12 (for example, various wirings, Hall sensors, etc.) are omitted. Here, the N variable magnetic flux magnet modules VMM are modules provided in at least one of the rotor 11 and the stator 12. Below, as an example, a case will be described in which the N variable magnetic flux magnet modules VMM are provided in the rotor 11. Note that the N variable magnetic flux magnet modules VMM may be provided in the stator 12 instead of the rotor 11, or may be provided in both the rotor 11 and the stator 12.

[0016] The rotor 11 is equipped with N variable flux magnet modules VMM. N may be any integer equal to or greater than 1. In the example shown in Fig. 1, the rotor 11 is equipped with six variable flux magnet modules VMM. In Fig. 1, these six variable flux magnet modules VMM are indicated by variable flux magnet module VMM-1 to variable flux magnet module VMM-6, respectively.

[0017] The variable flux magnet module VMM is a module that includes variable flux magnets VM. The variable flux magnets VM are magnets that can be demagnetized or magnetized by applying a magnetic field. In the rotating electric machine control system 1, field weakening of the rotating electric machine 10 is achieved by demagnetizing the variable flux magnets VM of the variable flux magnet module VMM.

[0018] The stator 12 includes a plurality of electromagnets respectively associated with the U-phase, V-phase, and W-phase. In order to simplify the drawing, the reference numerals of these electromagnets are omitted from Fig. 1 .

[0019] The control device 20 controls the rotating electric machine 10. In this embodiment, the rotating electric machine 10 is a three-phase brushless motor as described above. Therefore, the control device 20 rotates the rotating electric machine 10 by PWM (Pulse Width Modulation) control. That is, the control device 20 supplies PWM signals to a plurality of electromagnets (not shown) provided in the stator 12. Note that the control device 20 may be configured to be controlled by a device that is higher in rank than the control device 20. In this case, the rotating electric machine control system 1 may be configured to include such a higher-ranking device.

[0020] The control device 20 also determines the rotation speed of the rotating electric machine 10 based on, for example, an output signal from a Hall sensor (not shown) included in the rotating electric machine 10. Note that the control device 20 may be configured to determine the rotation speed using another method. The method for determining the rotation speed based on the output signal may be a known method or a method to be developed in the future. The control device 20 changes the magnetization of the variable flux magnet VM of the variable flux magnet module VMM included in the rotating electric machine 10 according to the determined rotation speed. More specifically, the control device 20 changes the magnetic force of the variable flux magnet VM to either a predetermined first magnetic force or a second magnetic force weaker than the first magnetic force according to the determined rotation speed. For example, if the rotation speed is less than a predetermined threshold, the control device 20 sets the magnetic force of the variable flux magnet VM to the first magnetic force. That is, if the rotation speed is less than a predetermined threshold and the magnetic force of the variable flux magnet VM is weaker than the first magnetic force, the control device 20 magnetizes the variable flux magnet VM. Furthermore, when the rotation speed is less than a predetermined threshold and the magnetic force of the variable magnetic flux magnet VM is the first magnetic force, the control device 20 does not change the magnetic force of the variable magnetic flux magnet VM. On the other hand, for example, when the rotation speed is equal to or greater than a predetermined threshold, the control device 20 sets the magnetic force of the variable magnetic flux magnet VM to the second magnetic force. That is, when the rotation speed is equal to or greater than a predetermined threshold and the magnetic force of the variable magnetic flux magnet VM is stronger than the second magnetic force, the control device 20 demagnetizes the variable magnetic flux magnet VM. Furthermore, when the rotation speed is equal to or greater than a predetermined threshold and the magnetic force of the variable magnetic flux magnet VM is the second magnetic force, the control device 20 does not change the magnetic force of the variable magnetic flux magnet VM. Through this control, the control device 20 can achieve field weakening of the rotating electric machine 10 and improve the efficiency of the rotating electric machine 10. Note that the control device 20 may be configured to discretely change the magnetic force of the variable magnetic flux magnet VM in three or more stages according to the rotation speed.

[0021] <Configuration of variable magnetic flux magnet module> The configuration of the variable magnetic flux magnet module VMM will be described below with reference to Fig. 2 and Fig. 3. Fig. 2 is a perspective view showing an example of the configuration of the variable magnetic flux magnet module VMM. Fig. 3 is a perspective view of the variable magnetic flux magnet module VMM shown in Fig. 2 when viewed from another direction.

[0022] Here, the three-dimensional coordinate system TC is a three-dimensional Cartesian coordinate system that indicates directions in a drawing in which the three-dimensional coordinate system TC is drawn. Hereinafter, for convenience of explanation, the X-axis in the three-dimensional coordinate system TC will be simply referred to as the X-axis. Hereinafter, for convenience of explanation, the Y-axis in the three-dimensional coordinate system TC will be simply referred to as the Y-axis. Hereinafter, for convenience of explanation, the Z-axis in the three-dimensional coordinate system TC will be simply referred to as the Z-axis.

[0023] The variable flux magnet module VMM includes a variable flux magnet VM and M magnetizing coils C.

[0024] 2 and 3, the variable magnetic flux magnet VM is a variable magnetic flux magnet with a flat rectangular shape. Note that the shape of the variable magnetic flux magnet VM may be other shapes instead of a flat rectangular shape. The variable magnetic flux magnet VM may be composed of a plurality of variable magnetic flux magnet segments, or may be composed of a single variable magnetic flux magnet segment. M magnetized coils C are arranged on a first surface M1 of the surfaces of the variable magnetic flux magnet VM. In the example shown in FIGS. 2 and 3, the first surface M1 is the surface of the variable magnetic flux magnet VM on the positive side of the Z axis. Also, M may be any integer equal to or greater than 1. Below, as an example, a case where M is 24 will be described. Therefore, 24 magnetized coils C are arranged on the first surface M1 shown in FIG. 2. In FIG. 2, these 24 magnetized coils C are respectively indicated by magnetized coils C-1 to C-24. 2, to avoid cluttering the drawing, reference numerals are omitted for magnetized coils C-4 to C-23. Hereinafter, as an example, a case will be described in which 24 magnetized coils C are arranged on the first surface M1 in a 6-row by 4-column matrix, with the rows extending in the X-axis direction and the columns extending in the Y-axis direction, as shown in FIGS. 2 and 3. In this case, magnetized coils C-1 to C-4 are arranged in the first row of the first surface M1 in the order of magnetized coil C-1, magnetized coil C-2, magnetized coil C-3, and magnetized coil C-4, facing the positive direction of the X-axis. Furthermore, magnetized coils C-5 to C-8 are arranged in the second row of the first surface M1 in the order of magnetized coil C-5, magnetized coil C-6, magnetized coil C-7, and magnetized coil C-8, facing the positive direction of the X-axis. In this case, magnetized coils C-9 to C-12 are lined up in the positive direction of the X-axis on the third row of the first surface M1 in the order of magnetized coil C-9, magnetized coil C-10, magnetized coil C-11, and magnetized coil C-12. In this case, magnetized coils C-13 to C-16 are lined up in the positive direction of the X-axis on the fourth row of the first surface M1 in the order of magnetized coil C-13, magnetized coil C-14, magnetized coil C-15, and magnetized coil C-16.In this case, magnetization coils C-17 to C-20 are arranged in the fifth row of the first surface M1 in the order of magnetization coil C-17, magnetization coil C-18, magnetization coil C-19, and magnetization coil C-20, facing the positive direction of the X-axis. In this case, magnetization coils C-21 to C-24 are arranged in the sixth row of the first surface M1 in the order of magnetization coil C-21, magnetization coil C-22, magnetization coil C-23, and magnetization coil C-24, facing the positive direction of the X-axis. Note that the arrangement of the 24 magnetization coils C on the first surface M1 may be other arrangements instead of this matrix arrangement. Furthermore, when the number of magnetization coils C arranged on the first surface M1 is one, the magnetization coil C may be arranged in any position on the first surface M1.

[0025] The magnetizing coil C may be any coil that can generate a magnetic field that penetrates the first surface M1 when a current is passed through the magnetizing coil C while the magnetizing coil C is disposed on the first surface M1. In the example shown in Fig. 2, the magnetizing coil C is a spiral coil having a coil plane that is substantially parallel to the surface on which the magnetizing coil C is disposed. Here, the coil plane of the magnetizing coil C is an imaginary plane having a thickness that includes the conductor wound as the magnetizing coil C and the opening of the magnetizing coil C.

[0026] When a current flows through each of the 24 magnetized coils C arranged on the first surface M1, the 24 magnetized coils C generate a magnetic field that penetrates the first surface M1. In other words, in this case, magnetic flux representing the magnetic field generated by the 24 magnetized coils C penetrates the first surface M1. Below, as an example, a case will be described in which the magnetic force of the variable magnetic flux magnet VM increases when the magnetic field penetrates the first surface M1 in the positive direction of the Z axis, and decreases when the magnetic field penetrates the first surface M1 in the negative direction of the Z axis. In this case, when a magnetized coil C generates a magnetic field that penetrates the first surface M1 in the positive direction of the Z axis, the magnetic force of a region of the variable magnetic flux magnet VM that overlaps with the coil surface of the magnetized coil C in the Z axis direction changes. As a result, the magnetic force of the region in the variable magnetic flux magnet VM increases (i.e., the region is magnetized). On the other hand, when a magnetized coil C generates a magnetic field that penetrates the first surface M1 in the negative direction of the Z axis, the magnetic force changes in the area of ​​the variable magnetic flux magnet VM that overlaps with the magnetized coil C in the Z axis direction. As a result, the magnetic force in that area of ​​the variable magnetic flux magnet VM decreases (i.e., that area is demagnetized).

[0027] Here, a variable flux magnet module X (e.g., a conventional variable flux magnet module, etc.) different from the variable flux magnet module VMM has a magnetizing coil made of a conductor wound around the side of the variable flux magnet. For this reason, the strength of the magnetic field generated by the magnetizing coil often differs between the center of the magnetizing coil and the outer edge of the magnetizing coil. Such differences in magnetic field strength are undesirable because they increase individual differences between the rotating electric machines.

[0028] In contrast, in the variable flux magnet module VMM, each of the 24 magnetized coils C is arranged on the first surface M1 of the variable flux magnet VM. This means that the 24 magnetized coils C are included inside the outline of the first surface M1 in the direction perpendicular to the first surface M1. That is, in the variable flux magnet module VMM, the area of ​​the coil surface of the magnetized coils C arranged on the first surface M1 can be made smaller than the area of ​​the first surface M1. This situation does not depend on the number of magnetized coils C. For this reason, in the variable flux magnet module VMM, for each of the 24 magnetized coils C, the degree of variation in the strength of the magnetic field penetrating the coil surface of the magnetized coils C in the Z-axis direction is smaller than the degree of variation in the strength of the magnetic field penetrating the coil surface of the magnetized coils of the variable flux magnet module X. As a result, the variable flux magnet module VMM can reduce individual variations. This also means that the variable flux magnet module VMM can reduce individual differences between rotating electric machines 10 that include the variable flux magnet module VMM. Note that in the variable flux magnet module VMM, some of the 24 magnetized coils C may be configured not to be included inside the outline of the first surface M1 in the direction perpendicular to the first surface M1. Even in this case, the variable flux magnet module VMM reduces the degree of variation in the strength of the magnetic field that penetrates the coil surfaces of the magnetized coils C in the Z-axis direction. As a result, even in this case, the variable flux magnet module VMM can reduce individual differences between the variable flux magnet module VMM and the rotating electric machines 10.

[0029] Furthermore, in the variable magnetic flux magnet module VMM, the amount of change in the magnetic force of the variable magnetic flux magnet VM can be adjusted by changing the number of magnetization coils C arranged on the first surface M1, the area of ​​the coil surface of each magnetization coil C arranged on the first surface M1, the number of magnetization coils C that generate a magnetic field that penetrates the first surface M1 in the positive direction of the Z axis, the number of magnetization coils C that generate a magnetic field that penetrates the first surface M1 in the negative direction of the Z axis, the number of magnetization coils C that do not generate a magnetic field, etc.

[0030] Here, it is known that in the above-mentioned variable flux magnet module X, the magnetic force of the variable flux magnet changes significantly due to a slight difference in the current flowing through the magnetizing coil. For this reason, it can be difficult to change the magnetic force of the variable flux magnet to a desired magnetic force in the variable flux magnet module X. This means, for example, that it is not possible to perform field weakening in a rotating electric machine equipped with the variable flux magnet module X in a stepwise manner, and it can be difficult to further improve the efficiency of the rotating electric machine.

[0031] In contrast, the variable flux magnet module VMM can adjust the size of each magnetized coil C arranged on the first surface M1 depending on the application. As a result, even if the number of magnetized coils C arranged on the first surface M1 is one, the variable flux magnet module VMM can change the magnetic force of the variable flux magnet VM to a desired magnetic force by adjusting the area of ​​the coil surface of the single magnetized coil C arranged on the first surface M1. Naturally, if the number of magnetized coils C arranged on the first surface M1 is two or more, the variable flux magnet module VMM can control the adjustment of the number of magnetized coils C that generate a magnetic field that penetrates the first surface M1 in the positive direction of the Z axis, the number of magnetized coils C that generate a magnetic field that penetrates the first surface M1 in the negative direction of the Z axis, and the number of magnetized coils C that do not generate a magnetic field. Therefore, in this case, the variable flux magnet module VMM can adjust the amount of change in the magnetic force of the variable flux magnet VM even after manufacturing.

[0032] 2 and 3, the areas of the coil surfaces of the 24 magnetization coils C are approximately the same. However, the areas of the coil surfaces of some or all of the 24 magnetization coils C may be different from each other.

[0033] 2 and 3, each magnetized coil C is in contact with the first surface M1. When each magnetized coil C is in contact with the first surface M1, almost all of the magnetic field generated by each magnetized coil C penetrates the first surface M1. Therefore, when each magnetized coil C is in contact with the first surface M1, the variable flux magnet module VMM can more easily precisely change the magnetization of the variable flux magnet VM. In other words, in this case, the variable flux magnet module VMM can more reliably reduce individual variations. For example, each magnetized coil C can be arranged on the first surface M1 so as to be in contact with the first surface M1 by fixing it to the first surface M1 with an adhesive or the like. Note that some or all of the 24 magnetized coils C may be spaced apart from the first surface M1. In this case, the magnetized coils C that are spaced apart from the first surface M1 are arranged on the first surface M1 using, for example, various jigs or the like.

[0034] 2 and 3, the conductors wound as the 24 magnetized coils C do not overlap each other. Hereinafter, for convenience of explanation, among the regions of the variable magnetic flux magnet VM, a region that overlaps with a certain magnetized coil C in the Z-axis direction (i.e., a region that overlaps with the coil surface of that magnetized coil C) will be referred to as the magnetization change region of that magnetization coil C. That is, in this example, the magnetization change regions of the 24 magnetization coils C do not overlap. In this case, the magnetic field that penetrates the magnetization change region of a certain magnetization coil C and the magnetic field that penetrates the magnetization change region of another magnetization coil C are unlikely to strengthen or weaken each other. As a result, the variable magnetic flux magnet module VMM can prevent the control of changing the magnetic force of the variable magnetic flux magnet VM from becoming complicated.

[0035] 2 and 3, when the 24 magnetized coils C are adjacent to each other, the variable magnetic flux magnet module VMM can suppress the generation of eddy currents inside the conductors wound as the 24 magnetized coils C. In other words, in this case, the variable magnetic flux magnet module VMM can reduce eddy current loss.

[0036] <Variation 1 of the configuration of the variable magnetic flux magnet module> Below, a first modified example of the configuration of the variable magnetic flux magnet module VMM will be described with reference to FIG. 4. In this first modified example, the conductors wound as the magnetization coils C for some or all of the 24 magnetization coils C may partially overlap each other. Below, as an example, a case will be described in which the conductors wound as the magnetization coils C for all of the 24 magnetization coils C partially overlap each other. FIG. 4 is a perspective view showing a first modified example of the configuration of the variable magnetic flux magnet module VMM. Note that the configuration of the variable magnetic flux magnet module VMM according to this first modified example, other than the configuration in which the conductors wound as the magnetization coils C for all of the 24 magnetization coils C partially overlap each other, is the same as the configuration described in FIGS. 2 and 3, and therefore description thereof will be omitted.

[0037] For example, in FIG. 4, a portion of the conductor wound as the magnetizing coil C-1 overlaps with a portion of the conductor wound as the magnetizing coil C-2 and a portion of the conductor wound as the magnetizing coil C-5. Also, for example, in FIG. 4, a portion of the conductor wound as the magnetizing coil C-2 overlaps with a portion of the conductor wound as the magnetizing coil C-1, a portion of the conductor wound as the magnetizing coil C-3, and a portion of the conductor wound as the magnetizing coil C-6. That is, in FIG. 4, a portion of the conductor wound as each of the 24 magnetizing coils C overlaps with a portion of the conductor wound as an adjacent magnetizing coil C. This allows the variable magnetic flux magnet module VMM to increase the size of the magnetization region of each of the 24 magnetization coils C. In other words, the variable magnetic flux magnet module VMM can reduce the area of ​​the region of the first surface M1 other than the magnetization region of each of the 24 magnetization coils C.

[0038] <Modification 2 of the configuration of the variable magnetic flux magnet module> Below, a second modified example of the configuration of the variable magnetic flux magnet module VMM will be described with reference to FIG. 5. In this second modified example, the coil surfaces of some or all of the 24 magnetization coils C may be configured to partially overlap each other. As an example, the following describes a case where the coil surfaces of all 24 magnetization coils C partially overlap each other. FIG. 5 is a perspective view showing a second modified example of the configuration of the variable magnetic flux magnet module VMM. Note that the configuration of the variable magnetic flux magnet module VMM according to this second modified example, other than the configuration where the coil surfaces of the magnetization coils C partially overlap each other for all 24 magnetization coils C, is the same as the configuration described in FIGS. 2 and 3, and therefore description thereof will be omitted.

[0039] For example, in FIG. 5, a portion of the coil surface of the magnetized coil C-1 overlaps with a portion of the coil surface of the magnetized coil C-2 and a portion of the coil surface of the magnetized coil C-5. Also, for example, in FIG. 5, a portion of the coil surface of the magnetized coil C-2 overlaps with a portion of the coil surface of the magnetized coil C-1, a portion of the coil surface of the magnetized coil C-3, and a portion of the coil surface of the magnetized coil C-6. That is, in FIG. 5, a portion of the coil surface of each of the 24 magnetized coils C overlaps with a portion of the coil surface of an adjacent magnetized coil C. This allows the variable flux magnet module VMM to increase the size of the magnetization region of each of the 24 magnetized coils C as long as the individual differences between variable flux magnet modules VMM are not increased. In other words, the variable flux magnet module VMM can reduce the area of ​​the region of the first surface M1 other than the magnetization region of each of the 24 magnetized coils C. Furthermore, in the configuration of the variable magnetic flux magnet module VMM shown in FIG. 5, the degree of freedom in arranging the multiple magnetizing coils C on the first surface M1 can be improved.

[0040] <Variation 3 of the configuration of the variable magnetic flux magnet module> Hereinafter, a third modification of the configuration of the variable magnetic flux magnet module VMM will be described with reference to FIG. 6. In this third modification, a plurality of magnetization coils C may be arranged on the first surface M1 of the variable magnetic flux magnet module VMM so that the white or black areas of a virtual black and white checkerboard pattern arranged on the first surface M1 become magnetization variable areas. FIG. 6 is a perspective view showing the third modification of the configuration of the variable magnetic flux magnet module VMM. In the example shown in FIG. 6, the variable magnetic flux magnet module VMM includes 12 magnetization coils C instead of 24 magnetization coils C. Note that the configuration of the variable magnetic flux magnet module VMM according to this third modification is the same as the configuration described in FIGS. 2 and 3 except for the configuration in which a plurality of magnetization coils C are arranged on the first surface M1 so that the white or black areas of the checkerboard pattern become magnetization variable areas, and therefore description thereof will be omitted.

[0041] <Fourth modified example of variable magnetic flux magnet module configuration> Below, a fourth modified example of the configuration of the variable magnetic flux magnet module VMM will be described with reference to FIG. 7. In this fourth modified example, in addition to the first surface M1, one or more magnetizing coils C may be arranged on a second surface M2 different from the first surface M1. Below, as an example, a case will be described in which the second surface M2 is the surface facing the first surface M1, i.e., the surface of the variable magnetic flux magnet VM on the negative side of the Z axis. Note that the second surface M2 may be a surface of the variable magnetic flux magnet VM other than the first surface M1 and the surface of the variable magnetic flux magnet VM on the negative side of the Z axis. FIG. 7 is a perspective view showing the fourth modified example of the configuration of the variable magnetic flux magnet module VMM.

[0042] The variable magnetic flux magnet VM shown in FIG. 7 has 24 magnetized coils C arranged on the first surface M1, and 24 magnetized coils C arranged on the second surface M2. Here, in this variable magnetic flux magnet VM, two magnetized coils C that overlap in the Z-axis direction are passed through with current so that they generate magnetic fields in the same direction, thereby increasing the amount of change in magnetic force in the magnetized regions of these two magnetized coils C. Note that in this variable magnetic flux magnet VM, the two magnetized coils C that overlap in the Z-axis direction may be formed from a single conductor, or may be formed from separate conductors. Furthermore, the arrangement of one or more magnetized coils C on the second surface M2 may be the same as or different from the 24 magnetized coils C arranged on the first surface M1.

[0043] The arrangement of the N magnetizing coils C on the first surface M1 may be a combination of the arrangements shown in each of Figures 3 to 7, or any other arrangement. The arrangement of one or more magnetizing coils C on the second surface M2 may be a combination of the arrangements shown in each of Figures 3 to 7, or any other arrangement.

[0044] <Variation 5 of the configuration of variable magnetic flux magnet module> Below, a fifth variation of the configuration of the variable magnetic flux magnet module VMM will be described with reference to Fig. 8. In this fifth variation, the variable magnetic flux magnet module VMM includes a fixed magnet MG in addition to a variable magnetic flux magnet VM and 24 magnetized coils C. Fig. 8 is a perspective view showing the fifth variation of the configuration of the variable magnetic flux magnet module VMM.

[0045] The fixed magnet MG may be any permanent magnet whose magnetic force hardly changes when a magnetic field is applied. In the example shown in Fig. 8, the fixed magnet MG is a flat, rectangular magnet. However, the shape of the fixed magnet MG may be other shapes instead of a flat, rectangular shape.

[0046] The fixed magnet MG is arranged on the opposite side of the 24 magnetized coils C across the variable flux magnet VM in the direction in which the variable flux magnet VM and the 24 magnetized coils C are stacked. In the example shown in FIG. 8, the fixed magnet MG is arranged on the opposite side of the 24 magnetized coils C across the variable flux magnet VM so as to overlap with at least a portion of the 24 magnetized coils C in the Z-axis direction. For example, as shown in FIG. 8, the fixed magnet MG is arranged on the second surface M2 of the variable flux magnet VM. In the example shown in FIG. 8, the fixed magnet MG is in contact with the variable flux magnet VM. Note that the fixed magnet MG may also be spaced apart from the variable flux magnet VM. In this case, the surface of the fixed magnet MG facing the variable flux magnet VM may be parallel to the second surface M2 of the variable flux magnet VM, or may be non-parallel to the second surface M2 of the variable flux magnet VM.

[0047] In this way, by including the fixed magnets MG in the variable flux magnet module VMM, the variable flux magnet module VMM can set the magnetic force of the variable flux magnet module to be the sum of the magnetic force of the variable flux magnets VM and the magnetic force of the fixed magnets MG. As a result, the variable flux magnet module VMM can use the fixed magnets MG to adjust the range over which the magnetic force of the variable flux magnets VM can be changed (the range of the magnitude of the magnetic force).

[0048] <Variation 6 of the configuration of the variable magnetic flux magnet module> Hereinafter, a sixth modification of the configuration of the variable magnetic flux magnet module VMM will be described. In the sixth modification, the variable magnetic flux magnet module VMM includes a magnetic body MB in addition to the variable magnetic flux magnet VM and 24 magnetized coils C.

[0049] In this embodiment, the magnetic body MB is an unmagnetized magnetic body, such as ferrite. That is, in this embodiment, a distinction is made between an unmagnetized magnetic body and a magnetized magnetic body such as the fixed magnet MG. The magnetic body MB is a magnetic body that covers at least a portion of the surface of the variable flux magnet VM. As an example, the following describes a case where the magnetic body MB is a rectangular parallelepiped magnetic body having a recess CC that houses the variable flux magnet VM together with 24 magnetized coils C arranged on the first surface M1. Note that the magnetic body MB may be composed of multiple magnetic body pieces or a single magnetic body piece. FIG. 9 is a diagram showing an example of the variable flux magnet VM housed in the recess CC of the magnetic body MB together with 24 magnetized coils C arranged on the first surface M1. FIG. 10 is a diagram showing an example of the variable flux magnet VM being removed from the recess CC of the magnetic body MB shown in FIG. 9. However, in FIGS. 9 and 10, to avoid complication, the 24 magnetized coils C are shown as three magnetized coils C.

[0050] 9, when the variable magnetic flux magnet VM is covered by the magnetic body MB, almost no (or no) magnetic flux passes through the inside of the conductor wound as the magnetized coil C arranged on the first surface M1. As a result, the variable magnetic flux magnet module VMM can suppress the generation of eddy currents inside the conductor wound as the magnetized coil C arranged on the first surface M1. That is, in this case, the variable magnetic flux magnet module VMM can reduce eddy current loss.

[0051] Note that when the variable magnetic flux magnet module VMM further includes a fixed magnet MG, the variable magnetic flux magnet VM may be configured to be housed in the recess CC of the magnetic body MB together with the fixed magnet MG, or may be configured to be housed in the magnetic body MB separately from the fixed magnet MG. When the variable magnetic flux magnet VM is housed in the magnetic body MB separately from the fixed magnet MG, the magnetic body MB has a recess CC that houses the variable magnetic flux magnet VM and a recess that houses the fixed magnet MG.

[0052] <Process by which the control device controls the variable magnetic flux magnet module> Hereinafter, a process in which the control device 20 controls the variable magnetic flux magnet module VMM will be described with reference to FIG. 11. FIG. 11 is a diagram showing an example of the flow of a process in which the control device 20 controls the variable magnetic flux magnet module VMM. The variable magnetic flux magnet module VMM may be configured to include a control unit that executes at least a part of the process of the control device 20 described below. The variable magnetic flux magnet module VMM may also be configured integrally with the control device 20. In this case, the control device 20 functions as a control unit for the variable magnetic flux magnet module VMM. In addition, in this embodiment, a description of the process in which the control device 20 performs PWM control to rotate the rotating electric machine 10 will be omitted. Below, as an example, a case will be described in which the control device 20 starts rotating the rotating electric machine 10 at a timing before the process of step S110 shown in FIG. 11 is performed. Also, as an example, a case will be described in which information indicating the initial value of the magnetic force of the variable magnetic flux magnet VM of the variable magnetic flux magnet module VMM is stored as magnetic force information in a storage unit (not shown) of the control device 20. The control device 20 repeatedly performs the process of the flowchart shown in FIG. 11, for example, until the rotation of the rotating electrical machine 10 is stopped.

[0053] The control device 20 determines whether the rotation speed of the rotating electric machine 10 is equal to or greater than a predetermined threshold value (step S110). Here, in step S110, the control device 20 acquires an output signal at a predetermined sampling period from, for example, a Hall sensor (not shown) provided in the rotating electric machine 10. When the output signal is acquired, the control device 20 identifies the rotation speed of the rotating electric machine 10 based on the acquired output signal. The method for identifying the rotation speed based on the output signal may be a known method or a method to be developed in the future.

[0054] When the control device 20 determines that the rotation speed of the rotating electric machine 10 is equal to or greater than a predetermined threshold value (step S110-YES), the control device 20 identifies the current magnetic force of the variable magnetic flux magnet VM of the variable magnetic flux magnet module VMM based on the magnetic force information stored in the memory unit of the control device 20, and determines whether the identified magnetic force is the second magnetic force (step S120).

[0055] When the control device 20 determines that the magnetic force of the variable magnetic flux magnet VM is the second magnetic force (step S120-YES), the control device 20 proceeds to step S110 and determines again whether the rotation speed of the rotating electrical machine 10 is equal to or greater than the predetermined threshold value.

[0056] On the other hand, if the control device 20 determines that the magnetic force of the variable magnetic flux magnet VM is not the second magnetic force (step S120-NO), it demagnetizes the variable magnetic flux magnet VM of the variable magnetic flux magnet module VMM (step S130). At this time, the control device 20 passes a current through each of the 24 magnetized coils C so that the magnetic flux passes through the magnetization region of each of the 24 magnetized coils C in the negative direction of the Z axis. In this way, the control device 20 demagnetizes the variable magnetic flux magnet VM of the variable magnetic flux magnet module VMM in step S130. Note that the magnitude of the current passed by the control device 20 to each of the 24 magnetized coils C in step S130 is determined, for example, by prior simulation, theoretical calculation of electromagnetics, repeated trial and error through experiments, etc., so that the net magnetic force of the variable magnetic flux magnet VM becomes the second magnetic force, but it may also be determined by other methods. After the process of step S130 is performed, the control device 20 updates the magnetic force information stored in the storage unit of the control device 20 to magnetic force information indicating the second magnetic force. Then, the control device 20 proceeds to step S110, where it again determines whether the rotation speed of the rotating electric machine 10 is equal to or greater than the predetermined threshold value.

[0057] On the other hand, if the control device 20 determines that the rotation speed of the rotating electric machine 10 is less than a predetermined threshold value (step S110-NO), it identifies the current magnetic force of the variable magnetic flux magnet VM of the variable magnetic flux magnet module VMM based on the magnetic force information stored in the memory unit of the control device 20, and determines whether the identified magnetic force is the first magnetic force (step S140).

[0058] When the control device 20 determines that the magnetic force of the variable magnetic flux magnet VM is the first magnetic force (step S140-YES), the process proceeds to step S110 and determines again whether the rotation speed of the rotary electric machine 10 is equal to or greater than the predetermined threshold value.

[0059] On the other hand, if the control device 20 determines that the magnetic force of the variable magnetic flux magnet VM is not the first magnetic force (step S140-NO), it magnetizes the variable magnetic flux magnet VM of the variable magnetic flux magnet module VMM (step S150). At this time, the control device 20 passes a current through each of the 24 magnetized coils C so that the magnetic flux passes through the magnetized region of each of the 24 magnetized coils C in the positive direction of the Z axis. In this way, the control device 20 magnetizes the variable magnetic flux magnet VM of the variable magnetic flux magnet module VMM in step S150. Note that the magnitude of the current passed by the control device 20 to each of the 24 magnetized coils C in step S150 is determined, for example, by prior simulation, theoretical calculation of electromagnetics, repeated trial and error through experiments, etc., so that the net magnetic force of the variable magnetic flux magnet VM becomes the first magnetic force, but it may also be determined by other methods. After the process of step S150 is performed, the control device 20 updates the magnetic force information stored in the storage unit of the control device 20 to magnetic force information indicating the first magnetic force. Then, the control device 20 proceeds to step S110, where it again determines whether the rotation speed of the rotating electric machine 10 is equal to or greater than the predetermined threshold value.

[0060] As described above, the control device 20 causes current to flow through each of the one or more magnetizing coils C included in the variable magnetic flux magnet module VMM in accordance with the rotation speed of the rotating electric machine 10, thereby varying the magnetization of the variable magnetic flux magnet VM. This allows the control device 20 to change the magnetic force of the variable magnetic flux magnet VM to a desired magnetic force. As a result, the control device 20 can achieve highly accurate field weakening of the rotating electric machine 10, thereby improving the efficiency of the rotating electric machine 10.

[0061] Note that in step S110, the control device 20 may be configured to compare, for example, the rotation speed of the rotating electric machine 10 with two thresholds: a certain threshold A1 and a threshold A2 that is smaller than threshold A1. In this case, for example, if the control device 20 determines that the rotation speed is equal to or greater than threshold A1, the process proceeds to step S120, and if the control device 20 determines that the rotation speed is less than threshold A2, the process proceeds to step S140. This allows the control device 20 to control the variable flux magnet module VMM in consideration of hysteresis.

[0062] <Modification 1 of the process in which the control device controls the variable magnetic flux magnet module> Hereinafter, with reference to FIG. 12 , a first modification of the process in which the control device 20 controls the variable magnetic flux magnet module VMM will be described. In this first modification, the control device 20 passes current through each of the 24 magnetized coils C so that the times at which current flows through each of the 24 magnetized coils C do not overlap. This allows the control device 20 to reduce the maximum value of the current passed through the magnetized coils C when changing the magnetization of the variable magnetic flux magnet VM. As a result, the control device 20 can reduce the size of the power supply connected to the control device 20. FIG. 12 is a diagram showing a first modification of the process flow in which the control device 20 controls the variable magnetic flux magnet module VMM. Note that the variable magnetic flux magnet module VMM may be configured to include a control unit that executes at least some of the processes of the control device 20 described below. Furthermore, the variable magnetic flux magnet module VMM may be configured integrally with the control device 20. In this case, the control device 20 functions as a control unit for the variable magnetic flux magnet module VMM. As an example, a case in which the control device 20 starts rotating the rotating electric machine 10 before the process of step S210 shown in FIG. 12 is performed will be described below. In the following, as an example, a case will be described in which information indicating the initial value of the magnetic force of the variable magnetic flux magnet VM of the variable magnetic flux magnet module VMM is stored as magnetic force information in a storage unit (not shown) of the control device 20. The control device 20, for example, repeatedly performs the processing of the flowchart shown in Fig. 12 until the rotation of the rotating electric machine 10 is stopped.

[0063] The control device 20 determines whether the rotation speed of the rotating electrical machine 10 is equal to or greater than a predetermined threshold value (step S210). Here, the processing of step S210 is the same as the processing of step S110 shown in FIG. 11, and therefore a detailed description thereof will be omitted.

[0064] When the control device 20 determines that the rotation speed of the rotating electric machine 10 is equal to or greater than a predetermined threshold value (step S210-YES), the control device 20 identifies the current magnetic force of the variable magnetic flux magnet VM of the variable magnetic flux magnet module VMM based on the magnetic force information stored in the memory unit of the control device 20, and determines whether the identified magnetic force is the second magnetic force (step S220).

[0065] When the control device 20 determines that the magnetic force of the variable magnetic flux magnet VM is the second magnetic force (step S220-YES), the process proceeds to step S210 and determines again whether the rotation speed of the rotating electrical machine 10 is equal to or greater than the predetermined threshold value.

[0066] On the other hand, if the control device 20 determines that the magnetic force of the variable magnetic flux magnet VM is not the second magnetic force (step S220-NO), it selects each of the 24 magnetized coils C provided in the variable magnetic flux magnet module VMM as a target coil one by one, and repeats the process of step S240 for each selected target coil (step S230). Note that the order in which each of the 24 magnetized coils C is selected as a target coil one by one may be random or may be a predetermined order. The predetermined order may be any order.

[0067] After the target coil is selected in step S230, the control device 20 passes a current through the selected target coil to demagnetize the magnetization region of the target coil (step S240). At this time, the control device 20 passes a current through the target coil so that magnetic flux passes through the magnetization region of the target coil in the negative direction of the Z axis. As a result, the control device 20 demagnetizes the magnetization region of the target coil in step S240. Note that the magnitude of the current passed through the target coil by the control device 20 in step S240 is determined, for example, by prior simulation, theoretical calculation of electromagnetics, repeated trial and error experiments, etc., so that the net magnetic force of the variable magnetic flux magnet VM becomes the second magnetic force when demagnetization of all the magnetization regions of each of the 24 magnetized coils C is completed, but may be determined by other methods. After the processing of step S240, the control device 20 proceeds to step S230 and selects the next target coil. If there is no unselected magnetized coil C that can be selected as the next target coil in step S230, the control device 20 ends the repeated processing of steps S230 to S240. Thereafter, the control device 20 updates the magnetic force information stored in the storage unit of the control device 20 to magnetic force information indicating the second magnetic force. Then, the control device 20 proceeds to step S210, where it again determines whether the rotation speed of the rotating electric machine 10 is equal to or greater than the predetermined threshold value.

[0068] In this way, by repeating steps S230 to S240, the control device 20 reduces the magnetic force of the variable flux magnet VM from the first magnetic force to the second magnetic force. At this time, the control device 20 passes current through two or more magnetized coils C so that the time during which current flows through each of the 24 magnetized coils C does not overlap. This allows the control device 20 to reduce the maximum value of the current passed through the magnetized coils C during the magnetization of the variable flux magnet VM. This can be clearly understood by looking at FIG. 13. FIG. 13 is a timing chart showing an example of the temporal change in the magnitude of the current passed through the variable flux magnet module VMM by the control device 20 by repeating steps S230 to S240. The vertical axis of the graph shown in FIG. 13 represents the magnitude of the current. The horizontal axis of the graph represents the elapsed time. For example, in the repeated processing of steps S230 to S240 shown in FIG. 12, the time during which the control device 20 passes current through each target coil is, for example, 100 microseconds. That is, the width of each pulse on the graph is 100 microseconds. That is, each solid-line pulse on the graph indicates the magnitude of the current flowing through one of the 24 magnetized coils C. In this case, the control device 20 completes the flow of current through all 24 magnetized coils C within 2.4 milliseconds, completing the demagnetization of the variable flux magnet VM. At this time, the control device 20 flows current through two or more magnetized coils C so that the times at which current flows through each of the 24 magnetized coils C do not overlap. Therefore, in the example shown in FIG. 13, the maximum value of the current that the control device 20 flows through the variable flux magnet module VMM is the magnitude indicated by I1 on the graph. Meanwhile, for example, in step S130 shown in FIG. 11, the control device 20 flows current through all of the 24 magnetized coils C during the period from time T1 to time T2. For this reason, in step S130, the maximum value of the current that the control device 20 passes through the variable magnetic flux magnet module VMM is indicated by the height of the dotted pulse, and is the magnitude indicated by I2 shown on the graph. Note that I2 is approximately 24 times I1. In other words, when the control device 20 performs the processing of the flowchart shown in FIG. 12, the control device 20 can reduce the maximum value of the current that passes through the magnetization coil C when varying the magnetism of the variable magnetic flux magnet VM.As a result, in the rotating electrical machine control system 1, the power supply connected to the control device 20 can be made smaller.

[0069] On the other hand, if the control device 20 determines that the rotation speed of the rotating electric machine 10 is less than a predetermined threshold value (step S210-NO), it identifies the current magnetic force of the variable magnetic flux magnet VM of the variable magnetic flux magnet module VMM based on the magnetic force information stored in the memory unit of the control device 20, and determines whether the identified magnetic force is the first magnetic force (step S250).

[0070] When the control device 20 determines that the magnetic force of the variable magnetic flux magnet VM is the first magnetic force (step S250-YES), the process proceeds to step S210 and determines again whether the rotation speed of the rotary electric machine 10 is equal to or greater than the predetermined threshold value.

[0071] On the other hand, if the control device 20 determines that the magnetic force of the variable magnetic flux magnet VM is not the first magnetic force (step S250-NO), it selects each of the 24 magnetized coils C included in the variable magnetic flux magnet module VMM as a target coil one by one, and repeats the process of step S270 for each selected target coil (step S260). Note that the order in which each of the 24 magnetized coils C is selected as a target coil one by one may be random, or may be a predetermined first order. The first order may be any order.

[0072] After the target coil is selected in step S260, the control device 20 passes a current through the selected target coil to magnetize the magnetization region of the target coil (step S270). At this time, the control device 20 passes a current through the target coil so that magnetic flux passes through the magnetization region of the target coil in the positive direction of the Z axis. As a result, the control device 20 magnetizes the magnetization region of the target coil in step S270. Note that the magnitude of the current passed by the control device 20 to the target coil in step S270 is determined, for example, by prior simulation, theoretical calculation of electromagnetics, repeated trial and error experiments, etc., so that the net magnetic force of the variable flux magnet VM becomes the first magnetic force when the magnetization of all the magnetic change regions of each of the 24 magnetized coils C is completed, but it may also be determined by other methods. After the processing of step S270, the control device 20 proceeds to step S260 and selects the next target coil. If there is no unselected magnetized coil C that can be selected as the next target coil in step S260, the control device 20 ends the repeated processing of steps S260 to S270. Thereafter, the control device 20 updates the magnetic force information stored in the storage unit of the control device 20 to magnetic force information indicating the first magnetic force. Then, the control device 20 proceeds to step S210, where it again determines whether the rotation speed of the rotating electric machine 10 is equal to or greater than the predetermined threshold value.

[0073] In this way, by repeating the processing of steps S260 to S270, the control device 20 increases the magnetic force of the variable magnetic flux magnet VM from the second magnetic force to the first magnetic force. At this time, the control device 20 passes current through each of two or more magnetized coils C so that the time during which current flows through each of the 24 magnetized coils C does not overlap. This allows the control device 20 to reduce the maximum value of the current passed through the magnetized coils C when changing the magnetization of the variable magnetic flux magnet VM. As a result, in the rotating electric machine control system 1, the power supply connected to the control device 20 can be made smaller.

[0074] As described above, the control device 20 passes current through each of the one or more magnetizing coils C included in the variable magnetic flux magnet module VMM in accordance with the rotation speed of the rotating electric machine 10, thereby changing the magnetization of the variable magnetic flux magnet VM. In this case, the control device 20 passes current through each of the 24 magnetizing coils C so that the times at which current flows through each of the 24 magnetizing coils C do not overlap. This allows the control device 20 to change the magnetic force of the variable magnetic flux magnet VM to a desired magnetic force, and also makes it possible to reduce the size of the power supply connected to the control device 20.

[0075] <Modification 2 of the process in which the control device controls the variable magnetic flux magnet module> Hereinafter, with reference to FIG. 14 , a second modification of the process in which the control device 20 controls the variable flux magnet module VMM will be described. In this second modification, the 24 magnetized coils C are classified into two or more groups. In this second modification, the control device 20 passes a current through each of the two or more groups so that the currents do not flow through the two or more groups at the same time. In this embodiment, when a current is passed through a group among the two or more groups, it means that a current is passed through one or more magnetized coils C classified into that group. By passing a current through the magnetized coils C at different times for each group, the control device 20 can solve problems caused by the arrangement of the 24 magnetized coils C on the first surface M1. Examples of such problems include the magnetic fields of adjacent magnetized coils C canceling each other out and increasing additional vibrations that occur in the rotation of the rotating electric machine 10 due to the magnetization of the variable flux magnet VM. For example, when classifying 24 magnetized coils C into two or more groups, two or more magnetized coils C classified into the groups into which the two or more magnetized coils C are classified can be arranged so that they are not adjacent to each other. In this case, the control device 20 can, for example, prevent overlapping of periods during which current flows through two or more adjacent magnetized coils C among the 24 magnetized coils C. As a result, the control device 20 can prevent magnetic fields of adjacent magnetized coils C from canceling each other out. Furthermore, when classifying 24 magnetized coils C into two or more groups, for example, the 24 magnetized coils C can be classified into two or more groups so that current flows through each magnetized coil C in an order that prevents the additional vibrations generated in the rotation of the rotating electric machine 10 from increasing when the variable magnetic flux magnets VM are magnetized. In this case, the control device 20 can prevent the additional vibrations generated in the rotation of the rotating electric machine 10 from increasing when the variable magnetic flux magnets VM are magnetized. It should be noted that such a classification method is determined, for example, by trial and error in advance experiments.

[0076] The following describes, as an example, a case where 24 magnetized coils C are classified into four groups, group G1 to group G4. For example, group G1 includes six magnetized coils C: magnetized coil C-1, magnetized coil C-6, magnetized coil C-11, magnetized coil C-16, magnetized coil C-17, and magnetized coil C-22. For example, group G2 includes six magnetized coils C: magnetized coil C-2, magnetized coil C-7, magnetized coil C-12, magnetized coil C-13, magnetized coil C-18, and magnetized coil C-23. For example, group G3 includes six magnetized coils C: magnetized coil C-3, magnetized coil C-8, magnetized coil C-9, magnetized coil C-14, magnetized coil C-19, and magnetized coil C-24. Furthermore, for example, group G4 is classified into six magnetized coils C: magnetized coil C-4, magnetized coil C-5, magnetized coil C-10, magnetized coil C-15, magnetized coil C-20, and magnetized coil C-21. In this case, the six magnetized coils C in each of these four groups are not adjacent to one another. Therefore, in this case, the control device 20 can vary the magnetization of the variable magnetic flux magnet VM while preventing the magnetic fields of adjacent magnetized coils C from canceling each other out.

[0077] FIG. 14 is a diagram showing a second modified example of the flow of processing in which the control device 20 controls the variable magnetic flux magnet module VMM. The variable magnetic flux magnet module VMM may be configured to include a control unit that executes at least a part of the processing of the control device 20 described below. The variable magnetic flux magnet module VMM may also be configured integrally with the control device 20. In this case, the control device 20 functions as a control unit for the variable magnetic flux magnet module VMM. The following describes, as an example, a case in which the control device 20 starts rotating the rotating electric machine 10 at a timing before the processing of step S310 shown in FIG. 14 is performed. The following also describes, as an example, a case in which information indicating the initial value of the magnetic force of the variable magnetic flux magnet VM of the variable magnetic flux magnet module VMM is stored as magnetic force information in a storage unit (not shown) of the control device 20. The control device 20, for example, repeatedly performs the processing of the flowchart shown in FIG. 14 until the rotation of the rotating electric machine 10 is stopped.

[0078] The control device 20 determines whether the rotation speed of the rotating electrical machine 10 is equal to or greater than a predetermined threshold value (step S310). Here, the processing of step S310 is the same as the processing of step S110 shown in FIG. 11, and therefore a detailed description thereof will be omitted.

[0079] When the control device 20 determines that the rotation speed of the rotating electric machine 10 is equal to or greater than a predetermined threshold value (step S310-YES), the control device 20 identifies the current magnetic force of the variable magnetic flux magnet VM of the variable magnetic flux magnet module VMM based on the magnetic force information stored in the memory unit of the control device 20, and determines whether the identified magnetic force is the second magnetic force (step S320).

[0080] When the control device 20 determines that the magnetic force of the variable magnetic flux magnet VM is the second magnetic force (step S320-YES), the control device 20 proceeds to step S310 and determines again whether the rotation speed of the rotating electrical machine 10 is equal to or greater than the predetermined threshold value.

[0081] On the other hand, if the control device 20 determines that the magnetic force of the variable magnetic flux magnet VM is not the second magnetic force (step S320-NO), it selects one of the four groups as a target group and repeats the process of step S340 for each selected target group (step S330). Note that the order in which the four groups are selected one by one as a target group may be random or may be a predetermined order. The predetermined order may be any order.

[0082] After the target group is selected in step S330, the control device 20 passes a current through the target group to demagnetize the magnetized regions of each of the six magnetized coils C included in the target group (step S340). At this time, the control device 20 passes a current through the target coils so that magnetic flux passes through the magnetized regions of each of the six magnetized coils C in the negative direction of the Z axis. As a result, the control device 20 demagnetizes the magnetized regions of each of the six magnetized coils C in step S340. Note that the magnitude of the current passed by the control device 20 to the target group in step S340 is determined, for example, by prior simulation, theoretical calculation of electromagnetics, repeated trial and error experiments, etc., so that the net magnetic force of the variable flux magnet VM becomes the second magnetic force when demagnetization of all the magnetized regions of each of the 24 magnetized coils C is completed, but may be determined by other methods. After the processing of step S340, the control device 20 proceeds to step S330 and selects the next target group. If there is no unselected group that can be selected as the next target group in step S330, the control device 20 ends the repeated processing of steps S330 to S340. Then, the control device 20 transitions to step S310 and again determines whether the rotation speed of the rotating electrical machine 10 is equal to or greater than the predetermined threshold value.

[0083] In this way, by repeating steps S330 to S340, the control device 20 reduces the magnetic force of the variable magnetic flux magnet VM from the first magnetic force to the second magnetic force. At this time, the control device 20 passes current through each of the four groups so that the times at which current flows through the four groups do not overlap. This allows the control device 20 to change the magnetism of the variable magnetic flux magnet VM while preventing the magnetic fields of adjacent magnetized coils C from canceling each other out. In other words, the control device 20 can solve the problems caused by the arrangement of the 24 magnetized coils C on the first surface M1.

[0084] FIG. 15 is a timing chart showing an example of temporal changes in the magnitude of the current that the control device 20 applies to the variable magnetic flux magnet module VMM through the repeated processing of steps S330 to S340. The vertical axis of the graph shown in FIG. 15 represents the magnitude of the current. The horizontal axis of the graph represents elapsed time. For example, in the repeated processing of steps S330 to S340 shown in FIG. 14, the time that the control device 20 applies current to each target group is, for example, 100 microseconds. That is, the control device 20 completes the application of current to all 24 magnetized coils C within 400 microseconds and completes demagnetization of the variable magnetic flux magnet VM. At this time, the control device 20 applies current to each of the four groups so that the times at which current flows through the four groups do not overlap. Therefore, in the example shown in FIG. 15, the maximum value of the current that the control device 20 applies to the variable magnetic flux magnet module VMM is the magnitude indicated by I3 on ​​the graph. Note that I3 is approximately six times the aforementioned I1. Timing T3 shown in FIG. 15 indicates, for example, an example of the timing when the control device 20 starts to pass current to group G1. Timing T4 shown in FIG. 15 indicates, for example, an example of the timing when the control device 20 finishes passing current to group G1. Timing T5 shown in FIG. 15 indicates, for example, an example of the timing when the control device 20 starts to pass current to group G2. Timing T6 shown in FIG. 15 indicates, for example, an example of the timing when the control device 20 finishes passing current to group G2. Timing T7 shown in FIG. 15 indicates, for example, an example of the timing when the control device 20 starts to pass current to group G3. Timing T8 shown in FIG. 15 indicates, for example, an example of the timing when the control device 20 finishes passing current to group G3. Timing T9 shown in FIG. 15 indicates, for example, an example of the timing when the control device 20 starts to pass current to group G4. Timing T10 shown in FIG. 15 indicates, for example, an example of the timing when the control device 20 finishes passing current to group G4.

[0085] On the other hand, if the control device 20 determines that the rotation speed of the rotating electric machine 10 is less than a predetermined threshold value (step S310-NO), it identifies the current magnetic force of the variable magnetic flux magnet VM of the variable magnetic flux magnet module VMM based on the magnetic force information stored in the memory unit of the control device 20, and determines whether the identified magnetic force is the first magnetic force (step S350).

[0086] When the control device 20 determines that the magnetic force of the variable magnetic flux magnet VM is the first magnetic force (step S350-YES), the process proceeds to step S310 and determines again whether the rotation speed of the rotating electrical machine 10 is equal to or greater than the predetermined threshold value.

[0087] On the other hand, if the control device 20 determines that the magnetic force of the variable magnetic flux magnet VM is not the first magnetic force (step S350-NO), it selects one of the four groups as a target group and repeats the process of step S370 for each selected target group (step S360). Note that the order in which the four groups are selected one by one as a target group may be random or may be a predetermined order. The predetermined order may be any order.

[0088] After the target group is selected in step S360, the control device 20 passes a current through the target group to magnetize the magnetized regions of each of the six magnetized coils C included in the target group (step S370). At this time, the control device 20 passes a current through the target coils so that magnetic flux passes through the magnetized regions of each of the six magnetized coils C in the positive direction of the Z axis. As a result, the control device 20 magnetizes the magnetized regions of each of the six magnetized coils C in step S370. Note that the magnitude of the current passed by the control device 20 to the target group in step S370 is determined, for example, by prior simulation, theoretical calculation of electromagnetics, repeated trial and error through experiments, etc., so that the net magnetic force of the variable flux magnet VM becomes the first magnetic force when the magnetization of all the magnetized regions of each of the 24 magnetized coils C is completed, but may be determined by other methods. After the processing of step S370, the control device 20 proceeds to step S360 and selects the next target group. If there is no unselected group that can be selected as the next target group in step S360, the control device 20 ends the repeated processing of steps S360 to S370. Then, the control device 20 proceeds to step S310 and again determines whether the rotation speed of the rotating electrical machine 10 is equal to or greater than the predetermined threshold value.

[0089] In this way, by repeating steps S360 to S370, the control device 20 increases the magnetic force of the variable magnetic flux magnet VM from the second magnetic force to the first magnetic force. At this time, the control device 20 passes current through each of the four groups so that the times at which current flows through the four groups do not overlap. This allows the control device 20 to change the magnetism of the variable magnetic flux magnet VM while preventing the magnetic fields of adjacent magnetized coils C from canceling each other out. In other words, the control device 20 can solve the problems caused by the arrangement of the 24 magnetized coils C on the first surface M1.

[0090] As described above, the control device 20 passes current through each of the one or more magnetizing coils C included in the variable magnetic flux magnet module VMM in accordance with the rotation speed of the rotating electric machine 10, thereby varying the magnetization of the variable magnetic flux magnet VM. In this case, the control device 20 passes current through each of the four groups so that the times at which current flows through the four groups do not overlap. This allows the control device 20 to vary the magnetization of the variable magnetic flux magnet VM while preventing the magnetic fields of adjacent magnetizing coils C from canceling each other out. In other words, the control device 20 can solve the problems caused by the arrangement of the 24 magnetizing coils C on the first surface M1.

[0091] <Modification 3 of the process in which the control device controls the variable magnetic flux magnet module> Hereinafter, with reference to FIG. 16 , a third variation of the process in which the control device 20 controls the variable magnetic flux magnet module VMM will be described. In this third variation, the control device 20 changes the magnetic force of the variable magnetic flux magnet VM to one of three or more magnetic forces of different magnitudes depending on the rotation speed of the rotating electric machine 10. This allows the control device 20 to more precisely adjust the magnetic force of the variable magnetic flux magnet. In this case, the storage unit of the control device 20 stores, for example, first correspondence information in which rotation speed range information is associated with magnetic force information indicating the magnetic force of the variable magnetic flux magnet VM for each of three or more rotation speed range information. Here, the rotation speed range information is information indicating the rotation speed range of the rotating electric machine 10. In addition, in this case, the storage unit of the control device 20 stores, for example, second correspondence information in which magnetic force information is associated with first identification information and second identification information for each of three or more magnetic force information. The first identification information is information including identification information for identifying one or more magnetized coils C through which a current is passed so as to generate a magnetic field that penetrates the magnetization region in the negative direction of the Z axis. The second identification information is information including identification information for identifying each of one or more magnetization coils C through which a current is passed so as to generate a magnetic field that penetrates the magnetization region in the positive direction of the Z axis.

[0092] FIG. 16 is a diagram showing a third modified example of the flow of processing by the control device 20 to control the variable magnetic flux magnet module VMM. The variable magnetic flux magnet module VMM may be configured to include a control unit that executes at least a part of the processing of the control device 20 described below. The variable magnetic flux magnet module VMM may also be configured integrally with the control device 20. In this case, the control device 20 functions as the control unit of the variable magnetic flux magnet module VMM. The following describes, as an example, a case in which the control device 20 starts rotating the rotating electric machine 10 at a timing before the processing of step S410 shown in FIG. 16 is performed. The following also describes, as an example, a case in which information indicating the initial value of the magnetic force of the variable magnetic flux magnet VM of the variable magnetic flux magnet module VMM is stored as magnetic force information in a storage unit (not shown) of the control device 20. The control device 20, for example, repeatedly performs the processing of the flowchart shown in FIG. 16 until the rotation of the rotating electric machine 10 is stopped.

[0093] The control device 20 acquires an output signal at a predetermined sampling period from a Hall sensor (not shown) provided in the rotating electrical machine 10, and identifies the rotation speed of the rotating electrical machine 10 based on the acquired output signal (step S410). The method for identifying the rotation speed based on the output signal may be a known method or a method to be developed in the future.

[0094] Next, the control device 20 identifies rotation speed range information that indicates a range including the rotation speed identified in step S410 from among the multiple pieces of rotation speed range information included in the first correspondence information stored in the storage unit of the control device 20. Then, the control device 20 identifies the magnetic force indicated by the magnetic force information associated with the identified rotation speed range information as the target magnetic force that is the target for changing the magnetic force of the variable magnetic flux magnet VM (step S420).

[0095] Next, the control device 20 identifies magnetic force information indicating the target magnetic force identified in step S420 from the magnetic force information included in the second correspondence information stored in the storage unit of the control device 20. Then, the control device 20 identifies first identification information and second identification information associated with the identified magnetic force information. The control device 20 identifies one or more magnetized coils C identified by the identified first identification information as demagnetization use magnetized coils, and identifies one or more magnetized coils C identified by the identified second identification information as magnetization use magnetized coils for magnetization (step S430). In FIG. 16, the processing of step S430 is indicated by "identify magnetized coils to be used."

[0096] Next, the control device 20 demagnetizes the magnetization change region of each of the one or more demagnetization use magnetized coils identified in step S430, and magnetizes the magnetization change region of each of the one or more magnetization use magnetized coils identified in step S430 (step S440). In FIG. 16, the processing of step S440 is indicated by "magnetization." By the processing of step S440, the control device 20 can change the magnetic force of the variable magnetic flux magnet VM to the target magnetic force. After the processing of step S440, the control device 20 transitions to step S410 and again identifies the rotation speed of the rotating electric machine 10.

[0097] As described above, the control device 20 changes the magnetic force of the variable magnetic flux magnet VM to one of three or more magnetic forces of different magnitudes depending on the rotation speed of the rotating electric machine 10. At this time, for example, when the control device 20 sets the magnetic force of the variable magnetic flux magnet VM to a first magnetic force, it passes current through one or more magnetization coils C of the 24 magnetization coils C that are associated with the first magnetic force (i.e., at least one of one or more demagnetization use magnetization coils and one or more magnetization use magnetization coils), and when the control device 20 sets the magnetic force of the variable magnetic flux magnet VM to a second magnetic force, it passes current through one or more magnetization coils C of the 24 magnetization coils C that are associated with the second magnetic force (i.e., at least one of one or more demagnetization use magnetization coils and one or more magnetization use magnetization coils). This allows the control device 20 to more precisely adjust the magnetic force of the variable magnetic flux magnet.

[0098] As described above, the variable flux magnet module according to the embodiment (variable flux magnet module VMM in the example described above) comprises a variable flux magnet (variable flux magnet VM in the example described above) and one or more coils (one or more magnetizing coils C in the example described above) arranged on at least a first surface (first surface M1 in the example described above) of the surfaces of the variable flux magnet. This makes it possible to reduce individual variations in the variable flux magnet module.

[0099] Furthermore, the variable magnetic flux magnet module may have a configuration in which two or more coils (24 magnetizing coils C in the example described above) are arranged on the first surface as one or more coils.

[0100] Furthermore, in the variable magnetic flux magnet module, a configuration may be used in which a portion of the conductor wound as a first coil of two or more coils (for example, magnetization coil C-1 in the example described above) overlaps with a portion of the winding of a second coil (for example, magnetization coil C-2 in the example described above) different from the first coil of the two or more coils.

[0101] Furthermore, the variable magnetic flux magnet module may be configured such that a portion of the coil surface of a third coil (in the example described above, for example, magnetization coil C-1) among the two or more coils overlaps with a portion of the coil surface of a fourth coil (in the example described above, for example, magnetization coil C-2) that is different from the third coil among the two or more coils.

[0102] Furthermore, the variable magnetic flux magnet module may be configured such that one or more coils are arranged on a second surface (second surface M2 in the example described above) that is different from the first surface of the surfaces of the variable magnetic flux magnet.

[0103] Furthermore, the variable magnetic flux magnet module may have a configuration in which the second surface is a surface opposite to the first surface.

[0104] In addition, the variable magnetic flux magnet module may be configured such that, in a direction perpendicular to the first surface (in the example described above, the Z-axis direction), at least one of the one or more coils is included inside the outline of the first surface.

[0105] Furthermore, the variable magnetic flux magnet module may be configured to further include a magnetic body (magnetic body MB in the example described above).

[0106] Furthermore, the variable magnetic flux magnet module may be configured such that the magnetic body covers at least a portion of the surface of the variable magnetic flux magnet.

[0107] Furthermore, in the variable flux magnet module, a configuration may be used in which the magnetic body has a recess (recess CC in the example described above) that houses the variable flux magnet together with one or more coils arranged on the first surface, and the variable flux magnet is housed in the recess together with the one or more coils arranged on the first surface.

[0108] Furthermore, in the variable magnetic flux magnet module, two or more coils are arranged on the first surface as one or more coils, and the variable magnetic flux magnet module may further include a control unit (in the example described above, a control device 20 configured integrally with the variable magnetic flux magnet module VMM) that passes current through each of the two or more coils.

[0109] Furthermore, in the variable magnetic flux magnet module, a configuration may be used in which the control unit passes current through each of two or more coils so that the times when current flows through each of the two or more coils do not overlap.

[0110] Furthermore, in the variable magnetic flux magnet module, two or more coils are classified into two or more groups (in the example described above, four groups: group G1 to group G4), and the control unit may be configured to pass current through each of the two or more groups so that the times when current flows through the two or more groups do not overlap.

[0111] Furthermore, in the variable magnetic flux magnet module, when the magnetic force of the variable magnetic flux magnet is set to a first magnetic force, the control unit passes a current through one or more first magnetic force coils (in the example described above, at least one of one or more demagnetization use coils and one or more magnetization use coils) among the two or more coils that are associated with the first magnetic force, and when the magnetic force of the variable magnetic flux magnet is set to a second magnetic force that is stronger than the first magnetic force, the control unit passes a current through one or more second magnetic force coils (in the example described above, at least one of one or more demagnetization use coils and one or more magnetization use coils) among the two or more coils that are associated with the second magnetic force.

[0112] The above describes in detail an embodiment of the present disclosure with reference to the drawings, but the specific configuration is not limited to this embodiment, and may be changed, replaced, deleted, etc., as long as it does not deviate from the gist of this disclosure.

[0113] Furthermore, a program for implementing the functions of any of the components of the above-described device may be recorded on a computer-readable recording medium and then loaded into a computer system for execution. Here, the device in question is, for example, the control device 20. Note that the term "computer system" here includes hardware such as an operating system (OS) and peripheral devices. Furthermore, the term "computer-readable recording medium" refers to portable media such as flexible disks, optical magnetic disks, ROMs, and compact disks (CDs)-ROMs, as well as storage devices such as hard disks built into computer systems. Furthermore, the term "computer-readable recording medium" also includes devices that retain a program for a certain period of time, such as volatile memory within a computer system that acts as a server or client when the program is transmitted via a network such as the Internet or a communication line such as a telephone line.

[0114] The above program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by transmission waves in the transmission medium. Here, the "transmission medium" that transmits the program refers to a medium that has the function of transmitting information, such as a network such as the Internet or a communication line such as a telephone line. The program may also be a program for realizing some of the functions described above, or may be a so-called differential file or differential program that can realize the functions described above in combination with a program already recorded in the computer system. [Explanation of symbols]

[0115] 1... rotating electric machine control system, 10... rotating electric machine, 11... rotor, 12... stator, 20... control device, C, C-1 to C-24... magnetization coil, M1... first surface, M2... second surface, MB... magnetic body, MG... fixed magnet, VM... variable flux magnet, VMM, VMM-1 to VMM-6... variable flux magnet module

Claims

1. a variable flux magnet; a plurality of coils arranged on at least a first surface of the surfaces of the variable magnetic flux magnet, the coil surfaces of the coils being parallel to one another; Equipped with The plurality of coils are arranged in a matrix. Variable flux magnet module.

2. a portion of the conductor wound as a first coil of the plurality of coils overlaps with a portion of a winding of a second coil different from the first coil of the plurality of coils; The variable flux magnet module of claim 1 .

3. a part of a coil surface of a third coil among the plurality of coils overlaps with a part of a coil surface of a fourth coil different from the third coil among the plurality of coils; The variable flux magnet module according to claim 2 .

4. One or more coils are arranged on a second surface of the variable magnetic flux magnet that is different from the first surface.

4. A variable flux magnet module according to claim 1.

5. The second surface is a surface opposite to the first surface. The variable flux magnet module according to claim 4 .

6. Further comprising a magnetic material, A variable flux magnet module according to any one of claims 1 to 5.

7. the magnetic body covers at least a portion of the surface of the variable magnetic flux magnet; The variable flux magnet module of claim 6.

8. the magnetic body has a recess that accommodates the variable magnetic flux magnet together with the plurality of coils arranged on the first surface, The variable magnetic flux magnet is accommodated in the recess together with the plurality of coils arranged on the first surface.

8. The variable magnetic flux magnet module according to claim 6 or 7.

9. The variable magnetic flux magnet module further includes a control unit that applies current to each of the plurality of coils. A variable flux magnet module according to any one of claims 1 to 8.

10. the control unit causes current to flow through each of the plurality of coils so that the times at which current flows through each of the plurality of coils do not overlap. The variable flux magnet module of claim 9.

11. The plurality of coils are classified into two or more groups, the control unit causes current to flow through each of the two or more groups so that times during which current flows through the two or more groups do not overlap. The variable flux magnet module of claim 9.

12. When the magnetic force of the variable magnetic flux magnet is set to a first magnetic force, the control unit passes a current through one or more first magnetic force coils among the plurality of coils that are associated with the first magnetic force, and when the magnetic force of the variable magnetic flux magnet is set to a second magnetic force that is stronger than the first magnetic force, the control unit passes a current through one or more second magnetic force coils among the plurality of coils that are associated with the second magnetic force.

12. A variable flux magnet module according to any one of claims 9 to 11.

13. A variable flux magnet module according to any one of claims 1 to 12, Rotating electric motor.

Images