Rotating Electric Machine

Abstract

To provide a rotary electric machine enabling high torque and high-speed rotation.SOLUTION: A rotary electric machine has a stator 12 in which 3-phase coils of the number of pole pairs p are arranged and which has slots of the number of slots Z1, and a first rotor 16 and a second rotor 18 capable of relatively rotating with respect to the stator 12, and arranged separately from each other. The first rotor 16 and the second rotor 18 have magnetic poles of the number of pole pairs Z2 in a rotor outer diameter part and magnetic poles of the number of pole pairs Z3 in a rotor inner diameter part respectively. The number of pole pairs p, the number of slots Z1, the number or pole pair Z2, and the number of pole pairs Z3 satisfy the condition of Z2=Z1±Z3, Z3=p, and a relative phase angle (skew angle) of the first rotor 16 and the second rotor 18 can be changed.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a rotating electric machine. [Background technology]

[0002] In a typical rotating electric machine, the maximum torque of the motor can be increased by increasing the rotor magnetic force, but this also increases the induced voltage, exceeding the upper limit voltage for motor control, making it impossible to rotate at high speed.

[0003] Therefore, a configuration has been disclosed in which the rotor's field magnet is composed of a first field magnet and a second field magnet that can rotate relative to the first field magnet, and a mechanism is provided that changes the phase of the composite magnetic poles of the field magnet with respect to the first field magnet as the rotor rotates (Patent Document 1). In this mechanism, by aligning the magnetic poles of different polarities of the first and second field magnets at low rotation speeds, the governor moves due to centrifugal force as the rotation speed increases, and a relative rotational force can be applied to the second field magnet.

[0004] In addition, a configuration has been disclosed in which a rotor, in which field magnets of opposite polarities are arranged alternately in the rotational direction, is divided into two in the axial direction, and the relative axial position of one of the two divided rotors is changed with respect to the other half of the rotor depending on the torque direction of the rotor, or the phase of the composite magnetic poles of the field magnets is changed with respect to the other magnetic pole of the two divided rotors depending on the torque direction of the rotor (Patent Document 2).

[0005] Also disclosed is a configuration that includes a rotating means capable of changing the relative phase between an inner rotor having an inner permanent magnet and an outer rotor having an outer permanent magnet, a first member arranged to be rotatable integrally with the outer rotor, and a second member arranged to be rotatable integrally with the inner rotor and that, together with the first member, defines a pressure chamber inside the inner rotor, and that changes the relative phase between the inner rotor and the outer rotor by supplying a working fluid to the pressure chamber (Patent Document 3).

[0006] Furthermore, a rotating electric machine control system has been disclosed that includes a stator with stator coils arranged at multiple locations along the circumferential direction, and a first rotor and a second rotor that are rotatable relative to the stator and arranged separately in the direction of the rotation axis, and that performs vector control of the current in the stator coil so as to transition the phase between the rotors, which is the relative phase difference between the second rotor and the first rotor (Patent Document 4). In this configuration, by switching the magnetic properties of the first rotor and the second rotor between an in-phase (same polarity) state and an opposite-phase (opposite polarity) state, it becomes possible to increase the maximum torque as the in-phase at low speeds and to reduce the induced voltage as the opposite-phase at high speeds. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 11-69743 [Patent Document 2] JP 2002-262534 A [Patent Document 3] JP 2007-244040 A [Patent Document 4] JP 2014-204517 A Summary of the Invention [Problem to be solved by the invention]

[0008] According to the conventional technology, the magnet magnetic flux can be suppressed by changing the relative phase angle of the two rotors to short the magnets of each rotor inside the rotor or to cancel the magnetic flux linking the coils. However, the magnet magnetic flux cannot be increased. Therefore, although it is possible to output up to high rotation speeds by changing the relative phase angle of the motor, it is not possible to increase the torque. [Means for solving the problem]

[0009] One aspect of the present invention is a rotating electric machine comprising: a stator having a number of slots Z1 and in which a three-phase coil with a number of pole pairs p is arranged; and a first rotor and a second rotor that are rotatable relative to the stator and arranged separately from each other, wherein the first rotor and the second rotor have magnetic poles with a number of pole pairs Z2 and magnetic poles with a number of pole pairs Z3, respectively, and the number of pole pairs p, the number of slots Z1, the number of pole pairs Z2 and the number of pole pairs Z3 satisfy the conditions Z2=Z1±Z3, Z3=p, and the relative phase angle between the first rotor and the second rotor can be changed.

[0010] Here, it is preferable that the first rotor and the second rotor each have magnetic poles with the number of pole pairs Z2 on the rotor outer diameter portion and magnetic poles with the number of pole pairs Z3 on the rotor inner diameter portion.

[0011] It is also preferable that the amplitude of the magnetic flux components of the magnetic poles of the pole pair number Z2 on the outer diameter portion of the rotor and the magnetic poles of the pole pair number Z3 on the inner diameter portion of the rotor can be changed by changing the relative phase angle between the first rotor and the second rotor.

[0012] In addition, when the magnetization direction of the magnetic poles of the pole pair number Z3 of the first rotor is the same as the magnetization direction of the magnetic poles of the pole pair number Z3 of the second rotor, it is preferable that the magnetization direction of the magnetic poles of the pole pair number Z2 of the first rotor is an opposite direction to the magnetization direction of the magnetic poles of the pole pair number Z2 of the second rotor.

[0013] In addition, it is preferable that the magnetic poles of the pole pair number Z2 on the outer diameter part of the rotor are arranged in the shape of spokes whose magnetization direction is oriented in the rotor circumferential direction.

[0014] It is also preferable that the relative phase angle between the first rotor and the second rotor can be changed by a mechanical mechanism or by vector control of a stator coil current for the stator.

[0015] It is also preferable that the relative phase angle between the first rotor and the second rotor can be changed so that the harmonic components of the electromotive force become large in a low-speed rotation range and the fundamental component of the electromotive force becomes large in a high-speed rotation range that is faster than the low-speed rotation range. Effect of the Invention

[0016] According to the present invention, it is possible to provide a rotating electric machine capable of high torque and high speed rotation. [Brief description of the drawings]

[0017] [Figure 1] 1 is a diagram showing a configuration of a rotating electric machine system according to an embodiment of the present invention; [Diagram 2] 3A and 3B are diagrams illustrating a configuration of magnetic poles of a first rotor in the first embodiment. [Diagram 3] 3A and 3B are diagrams illustrating a configuration of magnetic poles of a second rotor in the first embodiment. [Figure 4] FIG. 4 is a diagram showing the relationship between the relative phase angle (skew angle) and the no-load back electromotive voltage in the first embodiment. [Diagram 5] FIG. 4 is a diagram showing the relationship between the relative phase angle (skew angle) and the no-load back electromotive voltage amplitude in the first embodiment. [Figure 6] 13 is a diagram showing a configuration of magnetic poles of a second rotor in a second embodiment. FIG. [Figure 7] FIG. 11 is a diagram showing the relationship between the relative phase angle (skew angle) and the no-load back electromotive voltage amplitude in the second embodiment. [Figure 8] 13 is a diagram showing a configuration of magnetic poles of a first rotor in a third embodiment. FIG. [Figure 9] 13 is a diagram showing a configuration of magnetic poles of a second rotor in a third embodiment. FIG. [Figure 10] FIG. 13 is a diagram showing the relationship between the relative phase angle (skew angle) and the no-load back electromotive voltage amplitude in the third embodiment. [Figure 11] FIG. 4 is a diagram illustrating a q-axis magnetic circuit in the first and third embodiments. [Figure 12]FIG. 11 is a diagram showing the relationship between the rotation speed and torque of a rotating electrical machine system according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] [First embodiment] 1, a rotating electric machine system 100 according to a first embodiment of the present invention includes a rotating electric machine 102, a drive circuit 104, a power supply 106, and a control device 108. The rotating electric machine system 100 is mounted on, for example, a hybrid vehicle, an electric vehicle, a fuel cell vehicle, etc. The rotating electric machine system 100 can be used as a motor that generates driving force, and can also be used as a generator or a motor generator having both the functions of a motor and a generator.

[0019] The rotating electric machine 102 includes a housing 10, a stator 12, a rotating shaft 14, a first rotor 16, a second rotor 18, a locking mechanism 20, a bearing 22, and a rotation angle sensor 24. Note that the bearing 22 may not be provided, and the second rotor 18 may be configured to slide relative to the rotating shaft 14. In this embodiment, only one rotation angle sensor 24 is provided for sensorless control, but the first rotor 16 and the second rotor 18 may each be provided with a rotation angle sensor 24.

[0020] The rotating electric machine 102 generates a driving force for the rotating shaft 14 using electric power supplied from a power source 106 by a drive circuit 104 controlled by a control device 108. In addition, the rotational energy given to the rotating shaft 14 is converted into electric power by the drive circuit 104 and regenerated to the power source 106. The drive circuit 104 can be configured to include an inverter that converts the electric power from the power source 106 into AC. The power source 106 can be configured to include a power storage system including, for example, a secondary battery.

[0021] The housing 10 is configured to mechanically support the rotating electric machine 102. Inside the housing 10, a stator 12, a rotating shaft 14, a first rotor 16, a second rotor 18, a locking mechanism 20, a bearing 22, and a rotation angle sensor 24 are housed.

[0022] The stator 12 includes a stator core and a stator coil. The stator core is a hollow cylindrical member made of a laminate of electromagnetic steel sheets stacked in the axial direction of the rotating shaft 14. However, the material constituting the stator core is not limited to electromagnetic steel sheets, and may be a magnetic material such as an amorphous metal, a nanocrystalline soft magnetic material, or a dust core. The stator coil is a coil arranged in a plurality of slots provided on the inner peripheral surface of the stator core. A magnetic field can be generated in the stator coil by passing a current from a power source 106 through a drive circuit 104 to the stator coil.

[0023] A first rotor 16 and a second rotor 18 are arranged at a distance from each other in the axial direction on the rotating shaft 14. In the rotating electric machine system 100 of this embodiment, the second rotor 18 is arranged between the first rotor 16a, 16b, which is divided into two.

[0024] The first rotors 16a, 16b are fixed to the rotating shaft 14. The second rotor 18 is installed so as to be movable in the rotational direction with respect to the rotating shaft 14. That is, the second rotor 18 is rotatable relative to the rotating shaft 14. For example, the second rotor 18 is attached to the rotating shaft 14 via a bearing 22, and is rotatable with respect to the rotating shaft 14 by the bearing 22.

[0025] Furthermore, the second rotor 18 is provided with a locking mechanism 20 so that it can be fixed to the rotating shaft 14. For example, a gear is provided between the first rotor 16 (16a, 16b) and the second rotor 18, and the second rotor 18 can be locked so as not to rotate with respect to the rotating shaft 14 by the locking mechanism 20 using a lock pin. However, the locking mechanism provided on the second rotor 18 is not limited to this, and any mechanism can be used as long as it has a mechanism that can fix the second rotor 18 to the rotating shaft 14.

[0026] During normal operation of the rotating electric machine system 100, the locking mechanism 20 prevents the second rotor 18 from rotating relative to the rotating shaft 14, and both the first rotor 16 (16a, 16b) and the second rotor 18 contribute to the rotation of the rotating shaft 14. On the other hand, during field adjustment, the locking mechanism 20 is released to allow the second rotor 18 to rotate relative to the rotating shaft 14, and the second rotor 18 is rotated relative to the first rotor 16 (16a, 16b) to adjust its circumferential position, thereby adjusting the field of the rotors as a whole.

[0027] In this configuration, with the lock mechanism 20 in the engaged state and the first rotor 16 (16a, 16b) and the second rotor 18 not rotating relative to the rotating shaft 14 (normal operating state), a rotating magnetic field is formed by passing a current through the stator coil of the stator 12, thereby generating an output torque that rotates the rotating shaft 14 relative to the stator 12. Conversely, the rotational energy of the rotating shaft 14 can be converted into a current flowing through the stator coil of the stator 12 and regenerated.

[0028] In addition, by opening the locking mechanism 20 and allowing the second rotor 18 to rotate relative to the rotating shaft 14 (adjustment state) and passing current through the stator coil of the stator 12 to form a rotating magnetic field, it is possible to adjust the relative phase angle (skew angle) of the magnetic poles of the first rotor 16 (16a, 16b) and the second rotor 18 while generating output torque from the first rotor 16 (16a, 16b) to the rotating shaft 14.

[0029] At this time, a rotation angle sensor 24 is provided on the first rotor 16 (16a, 16b) and the second rotor 18, and the control device 108 receives the rotation angle of the first rotor 16 (16a, 16b) and the rotation angle of the second rotor 18 output from the rotation angle sensor 24 and adjusts the relative phase angle (skew angle) of the magnetic poles. That is, when adjusting the relative phase angle (skew angle) of the magnetic poles of the first rotor 16 (16a, 16b) and the second rotor 18, the lock mechanism 20 is first opened to set the second rotor 18 in a rotatable state (adjustment state) relative to the rotating shaft 14. In the adjustment state, the relative phase angle (skew angle) of the magnetic poles of the first rotor 16 (16a, 16b) and the second rotor 18 is changed by passing a current through the stator coil of the stator 12. Then, when the relative phase angle (skew angle) between the first rotor 16 (16a, 16b) and the second rotor 18 reaches a desired value, the locking mechanism 20 is brought into an engaged state, and the first rotor 16 (16a, 16b) and the second rotor 18 can be returned to a state where they are fixed to the rotating shaft 14. It is preferable to subject the current flowing through the stator coil of the stator 12 to so-called vector control.

[0030] The method of adjusting the relative phase (skew angle) between the first rotor 16 and the second rotor 18 is not particularly limited, and a configuration may be provided in which a mechanical mechanism such as an actuator is provided to rotate the first rotor 16 and the second rotor 18 relatively.

[0031] The first rotor 16 (16a, 16b) includes a base fixed to the rotating shaft 14, and a laminate in which electromagnetic steel sheets are laminated in the axial direction on the outer periphery of the base. However, the material constituting the laminate is not limited to electromagnetic steel sheets, and may be a magnetic material such as an amorphous metal, a nanocrystalline soft magnetic material, or a dust core. A plurality of first magnets and second magnets are arranged in the laminate along the circumferential direction.

[0032] In this embodiment, when 24 slots are provided at equal intervals (equal angles) on the inner peripheral wall of the stator 12 and three-phase stator coils are arranged as distributed windings, an eight-pole fundamental wave rotating magnetic field is generated when a sinusoidal current is passed through the three-phase stator coils. In addition, a 40-pole harmonic rotating magnetic field (fifth harmonic rotating magnetic field) that rotates in the opposite direction to the fundamental wave rotating magnetic field is also generated.

[0033] The first rotor 16 (16a, 16b) includes a first magnet 30 and a second magnet 32 ​​that are arranged at equal intervals along the circumferential direction, as shown in the partial cross-sectional view of Fig. 2. In Fig. 2, the magnetic pole directions of the first magnet 30 and the second magnet 32 ​​are indicated by arrows pointing from the S pole to the N pole.

[0034] The first magnet 30 has 40 magnetic poles arranged at equal intervals (equal angles) along the outer periphery (rotor circumferential direction) of the first rotor 16. The second magnet 32 ​​has 8 magnetic poles arranged at equal intervals (equal angles) along the outer periphery of the first rotor 16. In the rotating electric machine system 100 of this embodiment, the first magnet 30 is arranged on the rotor outer diameter portion, which is the outermost periphery of the first rotor 16, and the second magnet 32 ​​is arranged on the rotor inner diameter portion inside the first magnet 30. However, this is not limited to this, and the arrangement of the first magnet 30 and the second magnet 32 ​​may be interchanged.

[0035] The second rotor 18 comprises a laminated body in which electromagnetic steel sheets are stacked in the axial direction. However, the material constituting the laminated body is not limited to electromagnetic steel sheets, and may be a magnetic material such as an amorphous metal, a nanocrystalline soft magnetic material, or a dust core. As shown in the partial cross-sectional view of FIG. 3, the second rotor 18 comprises a first magnet 34 and a second magnet 36 that are equally spaced along the circumferential direction of the laminated body. In FIG. 3, the magnetic pole directions of the first magnet 34 and the second magnet 36 are indicated by arrows pointing from the south pole to the north pole.

[0036] In this embodiment, the second rotor 18 has a first magnet 34 and a second magnet 36 arranged in the same manner as the first rotor 16. That is, the first magnet 34 has 40 magnetic poles arranged at equal intervals (equal angles) along the outer periphery of the second rotor 18. The second magnet 36 has 8 magnetic poles arranged at equal intervals (equal angles) along the outer periphery of the second rotor 18. In this embodiment, the first magnet 34 is arranged on the outermost periphery of the second rotor 18, and the second magnet 36 is arranged inside the first magnet 34. However, this is not limited to this, and the arrangement of the first magnet 34 and the second magnet 36 may be interchanged.

[0037] In the following, the spatial magnetic field formed by the 8-pole second magnets 32 and 36 in the first rotor 16 and the second rotor 18 will be described as a fundamental wave, and the spatial magnetic field formed by the 40-pole first magnets 30 and 34 will be described as a harmonic (5th harmonic).

[0038] In addition, when the second rotor 18 is rotated relative to the first rotor 16, the state in which the magnetic pole directions of the first magnet 30 and the first magnet 34 and the second magnet 32 ​​and the second magnet 36 are aligned is defined as a state in which the relative phase angle (skew angle) between the first rotor 16 and the second rotor 18 is 0.

[0039] 4(a) to 4(c) show the change in the no-load back electromotive force with respect to the electrical angle when the relative phase angle (skew angle) is 0, 45°, and 9°, respectively. As shown in FIG. 4(a), when the relative phase angle (skew angle) is 0, the magnetization directions of the first magnet 30 and the first magnet 34, and the second magnet 32 ​​and the second magnet 36 are the same in the first rotor 16 and the second rotor 18. Therefore, both the fundamental wave and the fifth harmonic wave fluctuate with the maximum amplitude. As shown in FIG. 4(b), when the relative phase angle (skew angle) is 45°, the magnetization directions of the first magnet 30 and the first magnet 34, and the second magnet 32 ​​and the second magnet 36 are opposite to each other in the first rotor 16 and the second rotor 18. Therefore, both the fundamental wave and the fifth harmonic wave are almost zero.

[0040] 4(c), when the relative phase angle (skew angle) is 9°, the magnetization directions of the first magnet 30 and the first magnet 34 in the first rotor 16 and the second rotor 18 are opposite to each other, but the magnetization directions of the second magnet 32 ​​and the second magnet 36 are not opposite to each other. As a result, the fifth harmonic becomes almost zero, but the fundamental wave fluctuates with a certain degree of amplitude.

[0041] FIG. 5 shows the relationship between the no-load back electromotive force amplitude and the relative phase angle (skew angle) between the first rotor 16 and the second rotor 18. When the relative phase angle (skew angle) is 0, the no-load back electromotive force amplitudes in the fundamental wave and the fifth harmonic each show a maximum value, and the rotating electric machine system 100 as a whole can output a high torque. When the relative phase angle (skew angle) is 9°, the fundamental wave shows a certain degree of no-load back electromotive force amplitude, but the no-load back electromotive force amplitude for the fifth harmonic is almost zero. Therefore, the output torque can be limited in the rotating electric machine system 100 as a whole. Furthermore, when the relative phase angle (skew angle) is 45°, the no-load back electromotive force amplitudes in both the fundamental wave and the fifth harmonic are almost zero. Therefore, the output torque can be made almost zero in the rotating electric machine system 100 as a whole.

[0042] [Second embodiment] In the rotating electric machine system 100 in the second embodiment, as shown in the partial cross-sectional view of Fig. 6, the magnetization direction of the magnetic poles of the first magnet 34 of the second rotor 18 is arranged in the opposite direction to that of the first magnet 34 of the second rotor 18 in the first embodiment. In Fig. 6, the magnetic pole directions of the first magnet 34 and the second magnet 36 are indicated by arrows pointing from the S pole to the N pole. The other configurations are the same as those of the rotating electric machine system 100 in the first embodiment.

[0043] 7 shows the relationship of the no-load back electromotive force amplitude to the relative phase angle (skew angle) between the first rotor 16 and the second rotor 18 in this embodiment. When the relative phase angle (skew angle) is 0, the no-load back electromotive force amplitude of the fundamental wave is a maximum value, but the no-load back electromotive force amplitude for the fifth harmonic is a minimum value and is approximately 0. When the relative phase angle (skew angle) is 45°, the no-load back electromotive force amplitude of the fundamental wave is a minimum value and is approximately 0, but the no-load back electromotive force amplitude for the fifth harmonic is a maximum value. Furthermore, when the relative phase angle (skew angle) is 36°, the sum of the no-load back electromotive force amplitudes of the fundamental wave and the fifth harmonic is a minimum value.

[0044] According to this embodiment, the no-load back electromotive voltage amplitudes of the fundamental wave and the fifth harmonic can be maximized independently by adjusting the relative phase angle (skew angle) between the first rotor 16 and the second rotor 18. This improves the controllability of the output torque of the rotating electrical machine system 100.

[0045] In addition, since the distribution of the magnetic field changes in the first rotor 16 and the second rotor 18 by changing the magnetization direction of the first magnet 34 of the second rotor 18 as in this embodiment, it is preferable to optimize the shape and configuration of each of the first rotor 16 and the second rotor 18. By optimizing the first rotor 16 and the second rotor 18 to have different shapes and configurations, the performance of the rotating electric machine system 100 can be further improved.

[0046] [Third embodiment] In the rotating electric machine system 100 in the third embodiment, the first magnets 30 and 34 of the first rotor 16 and the second rotor 18 are arranged in a spoke shape with the magnetization direction oriented in the circumferential direction, as shown in the partial cross-sectional views of Figures 8 and 9. In Figures 8 and 9, the magnetic pole directions of the first magnet 30, the second magnet 32, the first magnet 34, and the second magnet 36 are indicated by arrows pointing from the S pole to the N pole.

[0047] In this embodiment, the first magnet 30 of the first rotor 16 and the first magnet 34 of the second rotor 18 are configured so that they are magnetized in opposite directions.

[0048] 10 shows the relationship of the no-load back electromotive force amplitude to the relative phase angle (skew angle) between the first rotor 16 and the second rotor 18 in this embodiment. As in the second embodiment, when the relative phase angle (skew angle) is 0, the no-load back electromotive force amplitude of the fundamental wave is a maximum value, but the no-load back electromotive force amplitude for the fifth harmonic is a minimum value and is approximately 0. When the relative phase angle (skew angle) is 45°, the no-load back electromotive force amplitude of the fundamental wave is a minimum value and is approximately 0, but the no-load back electromotive force amplitude for the fifth harmonic is a maximum value. Moreover, when the relative phase angle (skew angle) is 36°, the sum of the no-load back electromotive force amplitudes of the fundamental wave and the fifth harmonic is a minimum value.

[0049] Fig. 11 shows the difference between the magnetic circuits of the rotating electric machine system 100 in the first and second embodiments and the rotating electric machine system 100 in the third embodiment. In Fig. 11, the q-axis current magnetic flux is indicated by a dashed arrow. Note that, although Fig. 11 illustrates the first rotor 16, the same applies to the second rotor 18.

[0050] In the rotating electric machine system 100 in the first and second embodiments, as shown in Fig. 11(a), the first magnet 30 (or the first magnet 34) is arranged on the q-axis magnetic circuit when the fundamental wave is used, and therefore the magnetic resistance is high in the first rotor 16 and the second rotor 18. As a result, the q-axis current magnetic flux becomes relatively small, and the reluctance torque cannot be fully utilized when the fundamental wave is used.

[0051] In contrast, in the rotating electric machine system 100 in the third embodiment, as shown in FIG. 11(b), the first magnet 30 (or the first magnet 34) is not arranged on the q-axis magnetic circuit when the fundamental wave is used, and the magnetic flux passes through the electromagnetic steel plate (or the magnetic material such as amorphous metal, nanocrystalline soft magnetic material, dust core, etc.) between the first magnet 30 (or the first magnet 34). Therefore, the magnetic resistance in the first rotor 16 and the second rotor 18 is lower than that in the rotating electric machine system 100 in the first and second embodiments. As a result, the q-axis current magnetic flux is larger than that in the rotating electric machine system 100 in the first and second embodiments, and the reluctance torque can be fully utilized when the fundamental wave is used, and the output torque can be increased during fundamental wave driving.

[0052] Fig. 12 shows the results of calculating the relationship between the rotation speed and the output torque when switching between the fundamental wave and the fifth harmonic wave is performed by the relative phase angle (skew angle) in the rotating electrical machine system 100 in the third embodiment. Fig. 12 shows the characteristics (fundamental wave drive) when a three-phase current with a drive frequency synchronized with the rotation of the first rotor 16 and the second rotor 18 is passed through the stator coil of the stator 12 with the relative phase angle (skew angle) set to 0, and the characteristics (fifth harmonic drive) when a three-phase current with a drive frequency five times the rotation of the first rotor 16 and the second rotor 18 is passed through the stator coil of the stator 12 with the relative phase angle (skew angle) set to 45°.

[0053] According to the calculation results in Figure 12, it can be confirmed that by changing the relative phase angle (skew angle) between the first rotor 16 and the second rotor 18 so that the harmonic components of the electromotive force become large in the low rotation speed range and the fundamental wave component of the electromotive force becomes large in the high rotation speed range, which is faster than the low rotation speed range, it is possible to achieve both high output torque at low rotation speeds and high output at high rotation speeds.

[0054] Since the rotation direction of the rotating magnetic field of the fifth harmonic is opposite to that of the fundamental wave, the rotation direction of the current command value to stator 12 when driven by the fifth harmonic is opposite to that of the current command value to stator 12 when driven by the fundamental wave. If the drive frequency at the maximum rotation speed when driven by the fundamental wave is set as the upper limit of the drive frequency, the rotation speed when driven by the fifth harmonic will be 1 / 5 of that when driven by the fundamental wave.

[0055] Furthermore, in the rotating electrical machine system 100 in the first to third embodiments, 24 slots are provided in the stator 12 to form an 8-pole three-phase magnetic field, and the first rotor 16 and the second rotor 18 are configured to switch between an 8-pole fundamental wave and a 40-pole harmonic (5th order harmonic), but the present invention is not limited to this. That is, it is sufficient that the number of slots Z1 of the stator, the number of pole pairs p of the three-phase coil, the number of pole pairs Z2 of the first magnet 30 and the first magnet 34, and the number of pole pairs Z3 of the second magnet 32 ​​and the second magnet 36 satisfy the following conditions.

[0056] [Number 1] Z2 = Z1 ± Z3 Z3=P

[0057] In the above first to third embodiments, the number of slots Z1 of the stator is 24, the number of pole pairs p of the three-phase coil is 4, the number of pole pairs Z2 of the first magnets 30 and 34 is 20, and the number of pole pairs Z3 of the second magnets 32 and 36 is 4.

[0058] As described above, according to the rotating electric machine system 100 in the above embodiment, by adjusting the relative phase angle (skew angle) between the first rotor 16 and the second rotor 18, it is possible to switch between fundamental waves and harmonics in the magnetic flux density distribution in the gap of the field magnetic flux formed by the first rotor 16 and the second rotor 18. This increases the harmonics and increases the frequency of the three-phase current supplied to the stator coil of the stator 12 relative to the synchronous frequency of the first rotor 16 and the second rotor 18, thereby enabling the rotating electric machine system 100 to be driven with high output torque by the magnetic gear effect. In addition, by increasing the fundamental wave, the frequency of the three-phase current supplied to the stator coil of the stator 12 can be brought closer to the synchronous frequency of the first rotor 16 and the second rotor 18, allowing the rotating electric machine system 100 to rotate at high speed and further increase in output. In addition, by adjusting the relative phase angle (skew angle) between the first rotor 16 and the second rotor 18, it is also possible to suppress the no-load back electromotive voltage. [Explanation of symbols]

[0059] 10 housing, 12 stator, 14 rotating shaft, 16 first rotor, 18 second rotor, 20 locking mechanism, 22 bearing, 24 rotation angle sensor, 30, 34 first magnet, 32, 36 second magnet, 100 rotating electric machine system, 102 rotating electric machine, 104 drive circuit, 106 power supply, 108 control device.

Claims

1. A stator having a number of slots Z1, in which a three-phase coil having a number p of pole pairs is arranged; a first rotor and a second rotor that are rotatable relative to the stator and are disposed separately from each other; The first rotor has magnetic poles with a pole pair number Z2 and a pole pair number Z3, and the second rotor has magnetic poles with a pole pair number Z2 and a pole pair number Z3, The number of pole pairs p, the number of slots Z1, the number of pole pairs Z2, and the number of pole pairs Z3 are, Z2 = Z1 ± Z3 Z3=p Fulfill the conditions of A rotating electric machine, characterized in that the relative phase angle between the first rotor and the second rotor can be changed.

2. 2. The rotating electric machine according to claim 1, a first rotor and a second rotor each having magnetic poles with the number of pole pairs Z2 on an outer diameter portion of the rotor and magnetic poles with the number of pole pairs Z3 on an inner diameter portion of the rotor,

3. 3. A rotating electric machine according to claim 1, a rotor inner diameter portion having a pole pair number Z3 and a pole pair number Z2, the amplitude of magnetic flux components of the magnetic poles of the pole pair number Z2 on the outer diameter portion of the rotor and the magnetic poles of the pole pair number Z3 on the inner diameter portion of the rotor can be changed by changing the relative phase angle between the first rotor and the second rotor.

4. A rotating electric machine according to any one of claims 1 to 3, a magnetization direction of the magnetic poles of the pole pair number Z2 of the first rotor is opposite to a magnetization direction of the magnetic poles of the pole pair number Z2 of the second rotor when the magnetization direction of the magnetic poles of the pole pair number Z3 of the first rotor is the same as the magnetization direction of the magnetic poles of the pole pair number Z3 of the second rotor.

5. A rotating electric machine according to any one of claims 1 to 4, A rotating electric machine, characterized in that the magnetic poles of the pole pair number Z2 on the outer diameter part of the rotor are arranged in a spoke shape with the magnetization direction oriented in the rotor circumferential direction.

6. A rotating electric machine according to any one of claims 1 to 5, A rotating electric machine, characterized in that the relative phase angle between the first rotor and the second rotor can be changed by a mechanical mechanism or by vector control of a stator coil current for the stator.

7. A rotating electric machine according to any one of claims 1 to 6, A rotating electric machine characterized in that it is possible to change the relative phase angle between the first rotor and the second rotor so that the harmonic components of the electromotive force become large in a low-speed rotation range and the fundamental wave component of the electromotive force becomes large in a high-speed rotation range that is faster than the low-speed rotation range.

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