Modulation ring structure of magnetic gear compound permanent magnet motor and magnetic gear compound permanent magnet motor

Abstract

The application provides a modulation block structure, a double-shaft winding structure and a double-rotor magnetic gear composite permanent magnet motor, and belongs to the technical field of magnetic gear composite permanent magnet motors. The application increases the magnetic gear working mode of enhancing modulation, can improve the maximum torque of the magnetic gear without increasing the amount of permanent magnets, saves the modulation block connecting bridge under the premise of ensuring the stable support of the modulation ring winding, avoids the magnetic leakage field caused by the modulation block connecting bridge, improves the power factor of the winding, and under the condition that the d-axis and q-axis windings of different modulation blocks are respectively supplied with the same-phase current, the magnetic gear composite permanent magnet motor can still work normally through the rotation angle design of the modulation block and the winding, thereby providing a convenient condition for the series power supply of the d-axis and q-axis windings of different modulation blocks, a two-phase inverter can be used to supply power to the whole modulation ring winding, and the traditional pulse width modulation technology can be used to generate the power supply current, thereby greatly simplifying the power supply equipment and the current control method.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of magnetic gear compound permanent magnet motors, in particular to a modulation ring structure of a magnetic gear compound permanent magnet motor and the magnetic gear compound permanent magnet motor. BACKGROUND

[0002] The double-rotor magnetic gear compound motor has an inner permanent magnet rotor and an outer permanent magnet rotor, the inner rotor and the outer rotor generate fundamental magnetic motive forces with different pole pair numbers, a modulation ring between the two rotors is composed of alternately arranged silicon steel sheet modulation blocks and low magnetic permeability spaces, an alternating magnetic permeability distribution is formed in space, and an alternating current winding is arranged on the modulation ring. s i o ; in the formula, n s is the number of modulation blocks, p i and p o are pole pair numbers of the inner rotor and the outer rotor respectively. The fundamental magnetic motive forces of the inner rotor and the outer rotor are modulated by the alternating magnetic permeability of the modulation ring, and respectively generate harmonic magnetic fields equal to the pole pair number of the opposite rotor. When the inner rotor and the outer rotor rotate in opposite directions, and the speed ratio of the inner rotor to the outer rotor is equal to the pole pair number ratio of the outer rotor to the inner rotor, the harmonic magnetic fields formed by the inner rotor and the outer rotor through modulation are the same as the speed and rotation direction of the opposite rotor, and stable torque transmission is formed between the two rotors. The above ratio is the transmission ratio G of the magnetic gear unit in the double-rotor magnetic gear compound motor, that is: ; in the formula, n i and n o are the speeds of the inner rotor and the outer rotor respectively.

[0003] The modulation ring of the double-rotor magnetic gear compound motor generally has a three-phase winding, which has the same pole pair number as the inner rotor, and the rotating magnetic field thereof is directly coupled with the inner rotor magnetic field and coupled with the outer rotor magnetic field through the modulation of the modulation block, so as to form electromechanical energy conversion with the inner rotor and the outer rotor respectively. The three-phase winding is generally arranged in the low magnetic permeability space between the modulation blocks, and this arrangement needs to add a support structure between the modulation blocks to fix the winding. In order to meet the above manufacturing process requirements, the modulation ring is generally made of silicon steel sheets stacked together, the interconnection part between the modulation blocks can improve the mechanical strength of the whole modulation ring, and the modulation blocks form a slot for accommodating and fixing the winding. However, there is a large magnetic leakage field at the interconnection part of the silicon steel sheets connected together, which causes the decrease of the torque density and the power factor of the motor. In addition, the stator and its winding are between the two rotors, and the heat dissipation area is small, which easily causes high temperature rise and seriously restricts the output of the motor.

[0004] ​​The Chinese invention patent with application number 202111257392.6 discloses a current-modulated concentric magnetic gear structure and its current control method. This magnetic gear uses discrete circular modulation blocks, eliminates the connecting bridges between the modulation blocks, and slots the circular modulation blocks to arrange dual-axis windings. Although this structure can reduce the leakage magnetic field of the modulation ring and is beneficial to the heat dissipation of the modulation ring and its windings, due to the phase difference between the winding currents of different modulation blocks, the dual-axis windings of each modulation block require an independent inverter for power supply. The total number of inverters required is equal to the number of modulation blocks, and the power supply circuit is extremely complex. On the other hand, the modulation block winding current waveform disclosed in the patent needs to be calculated using a complex set of methods and cannot be simply generated using traditional pulse width modulation (PWM) technology. Summary of the Invention

[0005] The object of the present invention is to provide a modulation ring structure of a magnetic gear composite permanent magnet motor and a magnetic gear composite permanent magnet motor, so as to solve at least one technical problem existing in the above background technology.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] In one aspect, the present invention provides a modulation ring structure for a magnetic gear composite permanent magnet motor, comprising an outer rotor yoke, outer rotor permanent magnets, inner rotor permanent magnets, an inner rotor yoke, and a plurality of modulation blocks evenly arranged between the outer rotor permanent magnets and the inner rotor permanent magnets, wherein the modulation blocks are provided with slots; wherein the angle between the symmetry axis of a slot of one modulation block and the line connecting the central axis of the modulation block and the central axis of the modulation ring structure is 0°, and the modulation block is the first modulation block; and the remaining modulation blocks are arranged in sequence with the first modulation block as a reference in a direction consistent with the rotation direction of the inner rotor, and are, in order, the second modulation block, the third modulation block, the nth ... symmetry axis of a slot of one modulation block, and the line connecting the central axis s modulation blocks; in each modulation block, any slot is selected as the reference slot for the installation angle of the modulation block, which is uniformly described as a marking slot. The installation rule of the remaining modulation blocks is as follows: taking the marking slots of all the remaining modulation blocks coincide with the marking slot of the first modulation block as a benchmark, the remaining modulation blocks are uniformly arranged between the outer rotor permanent magnet and the inner rotor permanent magnet after rotating around their respective central axes at a certain angle compared to the previous modulation block. The angle between the symmetry axis of the marking slot in each modulation block and the line connecting its central axis and the central axis of the modulation ring structure is Among them, p i is the number of pole pairs of the inner rotor, n s is the total number of modulation blocks, and m is the number of the modulation block.

[0008] Furthermore, the d-axis winding and the q-axis winding of each modulation block are arranged in corresponding slots at a certain angle relative to the previous modulation block, and the angle between the axis of the d-axis winding and the line connecting the central axis of the modulation block and the central axis of the modulation ring structure is The angle between the q-axis winding axis and the line connecting the central axis of the modulation block and the central axis of the modulation ring structure is

[0009] In a second aspect, the present invention provides a magnetic gear composite permanent magnet motor, comprising the modulation ring structure of the magnetic gear composite permanent magnet motor as described above.

[0010] Furthermore, the modulation block windings constitute a dual-axis modulation surround group of the magnetic gear compound permanent magnet motor. The d-axis modulation surround group of the magnetic gear compound permanent magnet motor is formed by connecting the d-axis windings of all modulation blocks end to end in series. The q-axis modulation surround group of the magnetic gear compound permanent magnet motor is formed by connecting the q-axis windings of all modulation blocks end to end in series.

[0011] Furthermore, the dual-axis modulation surround group is powered by a two-phase AC power supply. The amplitudes of the power supply currents of the d-axis and q-axis modulation surround groups are equal, the phase difference is 90°, and the power supply current frequency is It is also equal to where n i and n o are the speeds of the inner and outer rotors, respectively, p i and p o are the pole pairs of the inner rotor and outer rotor respectively.

[0012] Furthermore, the space between the modulation blocks is used as an air duct, and air flow is introduced into the air duct along the axial direction of the motor to provide cooling conditions for the modulation ring and its biaxial winding.

[0013] The beneficial effects of the present invention are: an enhanced modulation magnetic gear working mode is added, which can increase the maximum torque of the magnetic gear without increasing the amount of permanent magnets; under the premise of ensuring the stable support of the modulation surround group, the modulation block connection bridge is eliminated, the leakage magnetic field caused by it is avoided, and the power factor of the winding is improved; through the rotation angle design of the modulation block and its winding, when the d-axis and q-axis windings of different modulation blocks are respectively supplied with the same phase current, the magnetic gear composite permanent magnet motor can still work normally, thereby providing convenient conditions for the d-axis and q-axis windings of different modulation blocks to be powered in series respectively, and a two-phase inverter can be used to power the entire modulation surround group, and the traditional pulse width modulation technology can be used to generate the power supply current, which greatly simplifies the power supply equipment and current control method; the axial air duct of the modulation ring enhances the heat dissipation effect of the modulation ring and its winding, thereby improving the load capacity of the motor.

[0014] Additional aspects and advantages of the present invention will be set forth in part in the following description, will become apparent from the following description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 This is a cross-sectional view of the modulation ring structure of the magnetic gear composite permanent magnet motor according to an embodiment of the present invention.

[0017] Figure 2 This is a schematic cross-sectional diagram of the modulation block and its dual-axis winding structure according to an embodiment of the present invention.

[0018] Figure 3 Schematic diagram of the installation rotation angle of the modulation block and its dual-axis winding according to an embodiment of the present invention.

[0019] Figure 4 This is a schematic diagram of the beginning and end of the d-axis and q-axis windings of the modulation block according to an embodiment of the present invention and their series connection.

[0020] Figure 5 : is a diagram of electromagnetic torque simulation results under different working modes of the embodiment of the present invention; wherein, Figure 5 (a) is the simulation result of electromagnetic torque under the ordinary magnetic gear working mode, Figure 5 (b) is the simulation result of electromagnetic torque under the working mode of magnetic gear with enhanced modulation effect. Figure 5 (c) is the simulation result of electromagnetic torque under the magnetic gear working mode with weakened modulation effect.

[0021] Figure 6 This is the electromagnetic torque simulation result of the embodiment of the present invention in the motor working mode.

[0022] Figure 7 This is a diagram showing the simulation results of the voltage and current of the surround group under the motor working mode with different axis modulation according to the embodiment of the present invention; wherein, Figure 7 (a) is the simulation result of the voltage and current of the d-axis modulation surround group in the motor working mode, Figure 7 (b) is the simulation results of the voltage and current of the q-axis modulation surround group in the motor working mode.

[0023] Figure 8 This is the electromagnetic torque simulation result of the embodiment of the present invention in the generator working mode.

[0024] Figure 9 Figures (a) and (b) are simulation results of d-axis and q-axis modulated field winding voltage and current in the generator operating mode, respectively, according to an embodiment of the present application. Figure 9 (a) is simulation results of d-axis modulated field winding voltage and current in the generator operating mode; Figure 9 (b) is simulation results of q-axis modulated field winding voltage and current in the generator operating mode. DETAILED DESCRIPTION

[0025] Embodiments of the present application are described in detail below with reference to the attached drawing figures, wherein the same or like reference numerals and characters in the drawing figures refer to components with the same or similar functions. The embodiments described are merely exemplary and are not to be construed as limiting the present application. The present application can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the application to those skilled in the art.

[0026] As used herein, the terms "have," "has," "have," "having," "include," "includes," "includes," "including," "comprise," "comprises," "comprising," or the like are used to indicate open-ended patterns that include a variety of possible elements, components, steps, or the like. However, such terms are not intended to, nor do they, exclude other possible elements, components, steps, or the like.

[0027] It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. It is also possible in the present technology that steps can be performed in different sequence from the performing order of steps described or illustrated herein or from the sequence illustrated and described herein, and that some steps can be performed simultaneously or with partial concurrence.

[0028] It is further understood that the use of relational terms such as first, second, top, bottom, upper, lower, up, down, left, right, and the like are used to help describe one embodiment, and are not to be construed as indicating either an ordered sequence or a necessary relationship between or among the various embodiments.

[0029] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. Also, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples without contradiction.

[0030] In the description of the present specification, the terms "first", "second" are only for descriptive purpose, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can be explicitly or implicitly included at least one of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly specified.

[0031] In the description of the present specification, the orientations or positional relationships indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present technology and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present technology.

[0032] Unless otherwise explicitly specified and limited, the terms "mount", "connect", "connect", "set" should be broadly understood, for example, it can be fixedly connected, set, or it can be detachably connected, set, or integrally connected, set. For those skilled in the art, the specific meaning of the above terms in the present technology can be understood according to the specific circumstances.

[0033] In order to facilitate the understanding of the present application, the present application will be further explained and described in specific embodiments in conjunction with the drawings, and the specific embodiments do not constitute a limitation on the embodiments of the present application.

[0034] Those skilled in the art should understand that the drawings are only schematic diagrams of the embodiments, and the components in the drawings are not necessarily necessary for the implementation of the present application.

[0035] Embodiment 1

[0036] As Figures 1 to 3 shown in the present embodiment 1, a modulation ring structure of a magnetic gear composite permanent magnet motor is provided, comprising an outer rotor yoke, an outer rotor permanent magnet, an inner rotor permanent magnet, an inner rotor yoke, and a plurality of modulation blocks uniformly arranged between the outer rotor permanent magnet and the inner rotor permanent magnet, the modulation blocks are provided with slots; the included angle between the symmetry axis of a slot of one of the plurality of modulation blocks and the line connecting the center axis of the modulation block and the center axis of the modulation ring structure is 0°, and the modulation block is the first modulation block; the remaining modulation blocks are arranged in sequence in the direction consistent with the rotation direction of the inner rotor with reference to the first modulation block, in sequence as the second modulation block, the third modulation block... the n smodulation blocks, each modulation block, select any one slot as the reference slot of the installation angle of the modulation block, uniformly described as the mark slot, the installation rule of the rest of the modulation blocks is: taking the coincidence of the mark slot of all the rest of the modulation blocks and the mark slot of the first modulation block as the reference, the rest of the modulation blocks are arranged in turn between the outer rotor permanent magnet and the inner rotor permanent magnet after rotating a certain angle around the center axis of each modulation block compared with the last modulation block, the angle between the symmetry axis of the mark slot in each modulation block and the connecting line between the center axis of the corresponding modulation block and the center axis of the modulation ring structure is wherein, p i is the pole pair number of the inner rotor, n s is the total number of the modulation blocks, and m is the number of the modulation blocks.

[0037] In the embodiment, the d-axis winding and the q-axis winding of each modulation block are arranged in the corresponding slots after rotating a certain angle around the center axis of each modulation block compared with the last modulation block, wherein the angle between the d-axis winding axis and the connecting line between the center axis of the modulation block and the center axis of the modulation ring structure is the angle between the q-axis winding axis and the connecting line between the center axis of the modulation block and the center axis of the modulation ring structure is

[0038] Embodiment 2

[0039] In the embodiment 2, a slot modulation block structure with a certain rotation angle configuration is provided, which comprises: a modulation block which is cylindrical as a whole, slots with equal area and equal spacing on the modulation block, and a specific installation rotation angle of each modulation block around its center axis compared with the last modulation block (i.e. a certain rotation angle around its center axis as the rotation axis compared with the last modulation block). Each modulation block is stacked by circular silicon steel sheets with slots, and the area and spacing of each slot are equal; each modulation block is rotated by a specific angle around its center axis when installed, the rotation direction is consistent with the rotation direction of the inner rotor, and n s modulation blocks are numbered as 1, 2, 3, …, n s according to the rotation direction of the inner rotor, and the installation rotation angle of each modulation block compared with the center axis of the corresponding modulation block and the center axis of the modulation ring structure (i.e. the angle between the symmetry axis of the mark slot in each modulation block and the connecting line between the center axis of the corresponding modulation block and the center axis of the modulation ring structure) is: wherein, m is the number of the modulation blocks. That is, the installation rotation angle of each modulation block is more than the installation rotation angle of the last modulation block by for example, if the installation rotation angle of the first modulation block is 0°, the installation rotation angle of the second modulation block is the installation rotation angle of the third modulation block is

[0040] In this embodiment, two sets of windings (i.e., d-axis winding and q-axis winding) with orthogonal axes are arranged in the slots of each modulation block. The rotation angle of the axis of the d-axis winding arranged on each modulation block relative to the line connecting the center of the modulation block and the motor axis is: The rotation angle of the axis of the q-axis winding arranged on each modulation block relative to the line connecting the center of the modulation block and the motor axis is: The direction of the rotation angle is consistent with the direction of the inner rotor. That is, the d-axis and q-axis winding axes of each modulation block are rotated more than the d-axis and q-axis winding axes of the previous modulation block. For example, if the angles of the d-axis and q-axis winding axes of the first modulation block are 0° and 90° respectively, then the angles of the d-axis and q-axis winding axes of the second modulation block are and The angles of the d-axis and q-axis winding axes of the third modulation block are and And so on.

[0041] In this embodiment, based on the above-mentioned modulation ring structure, a dual-axis modulation surround group structure of a dual-rotor magnetic gear composite permanent magnet motor is provided. The d-axis modulation surround group is formed by connecting the d-axis windings of all modulation blocks in series from the same direction, and the q-axis modulation surround group is formed by connecting the q-axis windings of all modulation blocks in series from the same direction. The d-axis and q-axis modulation surround groups are each powered by a single-phase AC power supply. The two-phase power supply currents have equal amplitudes, a phase difference of 90°, and a frequency equal to It is also equal to The space between the circular modulation blocks is used as an air duct to increase the heat dissipation area of ​​the stator, and the air flow is introduced into the air duct along the axial direction of the motor to provide sufficient cooling conditions for the modulation ring and its dual-axis winding.

[0042] In the embodiment, the double-rotor magnetic gear composite permanent magnet motor provided by the modulation ring and the double-axis winding structure has the magnetic gear, the motor and the generator working modes, wherein the magnetic gear working mode further includes three specific working modes of the ordinary magnetic gear, the magnetic gear with enhanced modulation effect and the magnetic gear with weakened modulation effect. In the ordinary magnetic gear working mode, the double-axis modulation ring winding is not connected with the current, one of the two rotors acts as the driving wheel and the other acts as the driven wheel, the driving wheel transmits the mechanical power to the driven wheel, and the load size of the ordinary magnetic gear working mode and which of the inner rotor and the outer rotor acts as the driving wheel / driven wheel is determined by the spatial phase angle between the working harmonic magnetic fields formed by the inner rotor and the outer rotor. In all the working modes of the magnetic gear composite permanent magnet motor with the double-axis modulation ring winding except the ordinary magnetic gear, the double-axis modulation ring winding needs to be connected with the current, and the working mode and the load state are determined by the spatial phase angle between the working harmonic magnetic fields formed by the two rotors and the phase of the current of the double-axis modulation ring winding. When the magnetic field formed by the current of the double-axis modulation ring winding on each modulation block is the same as the direction of the working harmonic magnetic field formed by the two rotors on each modulation block, the working mode is the magnetic gear with enhanced modulation effect, at this time, the double-axis modulation ring winding does not form the electromechanical energy conversion with the inner rotor and the outer rotor, compared with the ordinary magnetic gear working mode, the maximum torque that can be transmitted between the inner rotor and the outer rotor is increased. When the magnetic field formed by the current of the double-axis modulation ring winding on each modulation block is opposite to the direction of the working harmonic magnetic field formed by the inner rotor and the outer rotor on each modulation block, the working mode is the magnetic gear with weakened modulation effect, at this time, the double-axis modulation ring winding does not form the electromechanical energy conversion with the inner rotor and the outer rotor, compared with the ordinary magnetic gear working mode, the maximum torque that can be transmitted between the inner rotor and the outer rotor is decreased. When the direction of the magnetic field formed by the current of the double-axis modulation ring winding on each modulation block forms an angle of 0° and 180° outside between the direction of the working harmonic magnetic field formed by the inner rotor and the outer rotor on each modulation block, the working mode is the motor or the generator, at this time, the double-axis modulation ring winding forms the electromechanical energy conversion with the inner rotor and the outer rotor: in the motor working mode, part or all of the mechanical power of the two rotors is converted from the electrical power absorbed by the winding from the power supply; in the generator working mode, part or all of the mechanical power of the two rotors is converted into the electrical power output by the winding. In the motor and generator working modes, the double-axis modulation ring winding structure provided by the application can form a higher power factor.

[0043] Embodiment 3

[0044] For the problem of the double-rotor magnetic gear composite permanent magnet motor, the embodiment of the application discloses a modulation ring and a double-axis winding structure and a power supply mode, which has the effects of reducing the leakage magnetic field between the modulation blocks, improving the power factor of the motor / generator working mode and the torque transmission capacity of the magnetic gear working mode, enhancing the heat dissipation capacity of the stator and simplifying the power supply mode of the stator winding. The cross section of the double-rotor magnetic gear composite permanent magnet motor provided by the embodiment of the application is as shown in the figure. Figure 1As shown, it includes an inner rotor, an outer rotor, a modulation block and its dual-axis winding, an air duct and other structures. The inner rotor includes an inner rotor yoke and an inner rotor permanent magnet, and the outer rotor includes an outer rotor yoke and an outer rotor permanent magnet. The inner rotor has 2 pairs of poles, the outer rotor has 11 pairs of poles, and the number of modulation blocks is 13. Figure 2 As shown, the d-axis and q-axis windings with orthogonal axes are placed in 12 slots of equal area and equal spacing in the cylindrical modulation block, and the d-axis and q-axis windings each occupy 6 slots. Assume that during operation, the inner rotor rotates counterclockwise and the outer rotor rotates clockwise. Figure 1 and Figure 3 As shown, the modulation blocks are numbered in the counterclockwise direction. If the installation rotation angle of modulation block No. 1 is γ1 = 0° (i.e., the axis of the marking groove coincides with the line connecting the center of modulation block No. 1 and the motor axis), the installation rotation angle of modulation block No. 2 is (That is, the angle between the axis of the marking slot and the line connecting the center of the No. 2 modulation block and the motor axis is ), the installation rotation angle of modulation block No. 3 is (That is, the angle between the axis of the marking slot and the line connecting the center of the No. 3 modulation block and the motor axis is ), and so on. According to the same rule, the rotation angle of the d-axis winding axis of each modulation block is set, that is, the angles between the axes d1, d2, and d3 of the d-axis winding of modulation blocks 1, 2, and 3 and the lines connecting the centers of these modulation blocks and the motor axis are 0°, ... The rotation angles of the d-axis winding axes of other modulation blocks are similar. The axis of the q-axis winding of each modulation block is rotated 90° counterclockwise on the basis of the axis of the d-axis winding. That is to say, the angles between the axis q1, q2, q3 of the q-axis winding of modulation blocks 1, 2, and 3 and the line connecting the center of these modulation blocks and the motor axis are 90°, The rotation angles of the q-axis winding axes of other modulation blocks are similar.

[0045] The d-axis windings and q-axis windings of all modulation blocks are connected in series to form the modulation ring d-axis and q-axis windings of the entire motor, and are connected to a two-phase AC power supply. Figure 4 As shown, the tail end of each modulation block d-axis winding and the head end of the next modulation block d-axis winding are connected in series on the same side of the motor, that is, if the wire of each modulation block d-axis winding enters from the front side (backwards to the reader) of the slot marked with "×" (that is, the tail end of the modulation block d-axis winding), it will be connected to the back side of the slot marked with "·" (that is, the head end of the modulation block d-axis winding) of the next modulation block d-axis winding and exit from its front side (pointing to the reader), and so on to form the d-axis modulation surround group of the entire motor. The q-axis modulation surround group is also formed by the q-axis windings of each modulation block in series in the same way, that is, the wire of the q-axis winding of each modulation block enters from the slot marked with "×" (that is, the tail end of the modulation block d-axis winding) and exits from the front side (pointing to the reader), and so on. The front side of the slot marked (i.e. the tail end of the q-axis winding of the modulation block) is then connected to the q-axis winding of the next modulation block marked The circuit is connected to the back of the slot (i.e. the head end of the q-axis winding of the modulation block) and exits from the front side, and so on.

[0046] The dual-axis modulation surround group is powered by a two-phase inverter. The phase of the q-axis modulation surround group power supply current leads the phase of the d-axis modulation surround group power supply current by 90°. Assuming that the speeds of the inner and outer rotors are 330r / min and 60r / min respectively, the current frequency provided by the two-phase inverter is 11Hz.

[0047] Finite element methods were used to simulate the typical operating conditions of a magnetic gear composite permanent magnet motor with a dual-axis modulated winding assembly to verify its different operating modes. With the dual-axis modulated winding assembly open, the simulation model of the present invention was configured to operate in a normal magnetic gear mode under a certain load condition by adjusting the initial relative positions of the inner and outer rotors. Figure 5 (a) is a curve showing the change of electromagnetic torque of the two rotors over time in this state. It can be found that a stable torque transmission is formed between the two rotors, and the electromagnetic torque of the two rotors is both positive (i.e., the torque direction is both counterclockwise). Under the conditions of counterclockwise inner rotor rotation and clockwise outer rotor rotation set in the simulation model of this embodiment, the positive electromagnetic torque of the two rotors indicates that the inner and outer rotors are driven wheels and driving wheels respectively. Keeping the initial relative positions of the inner and outer rotors unchanged, according to the power supply method of the dual-axis modulation surround group provided by the present invention, a two-phase current with a certain amplitude and a phase difference of 90° is introduced into the d-axis and q-axis modulation surround groups, and by adjusting the phase of the current (maintaining a 90° phase difference between the two phases), until the total power of the dual-axis winding is basically zero (only a small input power is converted into internal loss of the motor), the mechanical power of the two rotors is equal and its torque is increased compared with the ordinary magnetic gear working mode, the curve showing the change of electromagnetic torque of the two rotors over time in this state is as follows: Figure 5 (b) As shown. At this time, the magnetic field formed by the winding current of each modulation block is in the same direction as the synthetic magnetic field formed by the permanent magnets of the inner and outer rotors on the modulation block. The modulation block winding current plays a role in strengthening the modulation, thereby improving the ability to transmit torque between the two rotors. In this state, the simulation model operates in a magnetic gear mode with enhanced modulation. The initial relative positions of the inner and outer rotors mentioned above are still maintained unchanged, and the currents of the above amplitudes are still passed through the d-axis and q-axis modulation winding groups. However, compared with the magnetic gear working mode with enhanced modulation, the phases of the two-phase currents are adjusted by 180° (maintaining a phase difference of 90° between the two-phase currents). Then, the simulation model of the embodiment of the present invention enters a magnetic gear working mode with weakened modulation. At this time, the total power of the dual-axis winding is also basically zero (only a small input power is converted into internal losses of the motor), and the mechanical power of the two rotors is equal, but its torque is reduced compared to the ordinary magnetic gear working mode.Figure 5 (c) is the curve of the electromagnetic torque of the two rotors with time in this state. At this time, the magnetic field formed by the winding current of each modulation block is opposite to the direction of the resultant magnetic field formed by the permanent magnets of the inner and outer rotors on the modulation block, and the winding current of the modulation block plays a role in weakening the modulation, thus weakening the ability of the two rotors to transmit torque.

[0048] By adjusting the initial relative position of the inner and outer rotors and the phase of the winding current of the double-shaft modulation ring of the simulation model of the embodiment of the present application, the angle between the direction of the magnetic field generated by the winding current of each modulation block and the direction of the resultant magnetic field formed by the permanent magnets of the inner and outer rotors on the modulation block is an angle other than 0° and 180°, and then the simulation model enters the motor or generator working mode. Figure 6 and Figure 7 are the curves of the electromagnetic torque of the two rotors and the voltage and current of the double-shaft modulation ring when the simulation model of the embodiment of the present application works in a certain load state in the motor mode (motor convention). The voltage of the modulation ring of the embodiment of the present application is relatively high, and the current value is relatively small, in order to clearly show the phase relationship between the current and the voltage, Figure 7 The current curve in is drawn after the original simulation data is enlarged by 30 times. According to the electromagnetic torque shown in Figure 6 , the inner rotor and the outer rotor of the simulation model of the embodiment of the present application in this state are the driven wheel and the driving wheel respectively, and the mechanical power of the former is greater than that of the latter. The excess mechanical power of the driven wheel is converted from the electric power input by the double-shaft modulation ring, which is consistent with the state shown in Figure 7 that the double-shaft modulation ring absorbs electric power. Figure 8 and Figure 9 are the curves of the electromagnetic torque of the two rotors and the voltage and current of the double-shaft modulation ring when the simulation model of the embodiment of the present application works in a certain load state in the generator mode (generator convention), wherein Figure 9 The current curve in is still drawn after the original simulation data is enlarged by 30 times. According to the electromagnetic torque shown in Figure 8 , the mechanical power of the inner rotor as the driven wheel is less than that of the outer rotor as the driving wheel. The excess mechanical power of the driving wheel is converted into electric power output by the double-shaft modulation ring, which is consistent with the state shown in Figure 9 that the double-shaft modulation ring emits electric power.

[0049] The current amplitude of the double-shaft modulation ring of the simulation model is kept unchanged, and under certain initial relative position of the inner and outer rotors, the phase of the winding current is adjusted (the phase difference between the two-phase winding currents is kept at 90°), to obtain different power and power factor of the double-shaft modulation ring. Taking the motor working mode as an example, Table 1 shows the different power and power factor of the double-shaft modulation ring obtained in the above process. It can be seen that, under certain current amplitude, the power of the double-shaft modulation ring reaches 80% of the maximum power (the maximum power Pmax =3488W) or above, the power factor can reach above 0.9; when the dual-axis modulation surround group power reaches above 60% of the maximum power, the power factor can still reach above 0.75. Although the power factor of the dual-axis modulation surround group is lower under the low power conditions shown in Table 1, it should be emphasized that the dual-axis modulation surround group power and power factor in Table 1 are obtained under the condition of constant current amplitude. When the required electric power is low, the power factor can be improved by reducing the dual-axis modulation surround group current and controlling its phase.

[0050] Table 1 Power and power factor of dual-axis modulation surround group

[0051]

[0052] In summary, for the dual-rotor magnetic gear composite permanent magnet motor, the modulation ring and dual-axis winding structure and power supply method of this embodiment have a more flexible magnetic gear working mode compared with the traditional dual-rotor magnetic gear composite permanent magnet motor. In particular, the magnetic gear working mode with enhanced modulation effect can utilize the magnetic field provided by the current of the dual-axis modulation surround group to enhance the modulation effect of the modulation ring without increasing the amount of permanent magnets. By increasing the current, the load capacity of the magnetic gear mode can be improved within a certain range. The dual-axis winding placed in the modulation block slot can obtain stable support without the need for a connecting bridge between the modulation blocks, avoiding the leakage magnetic field formed by the modulation block connecting bridge and the corresponding loss of torque density and power factor. The dual-axis modulation surround group is powered by a two-phase power supply, and the supply current can be generated using traditional pulse width modulation technology. The power supply equipment and current control technology are relatively simple. The air duct between the modulation blocks can improve the cooling effect of the stator and its windings located between the two rotors, which is beneficial to improving the load capacity of the dual-rotor magnetic gear composite permanent magnet motor in the magnetic gear, motor and generator working mode with enhanced modulation effect.

[0053] In summary, the embodiments of the present invention provide a modulation ring and dual-axis winding structure and power supply method for a dual-rotor magnetic gear composite permanent magnet motor, including: a circular modulation block with a slot and a modulation block dual-axis winding structure arranged in the slot and the installation rotation angle of the two, a dual-axis modulation surround group formed by the dual-axis (d-axis and q-axis) windings of each modulation block in series, a two-phase power supply and current frequency determination method of the dual-axis modulation surround group, and a stator cooling method using the space between the modulation blocks as an axial air duct. The advantages brought by the modulation ring and dual-axis winding structure and power supply method provided by the present invention include: adding an enhanced modulation action magnetic gear working mode, which can increase the maximum torque of the magnetic gear without increasing the amount of permanent magnets; while ensuring the stable support of the modulation surround group, the modulation block connection bridge is eliminated, avoiding the leakage magnetic field caused by it and improving the power factor of the winding; the modulation surround group is powered by a two-phase power supply based on traditional pulse width modulation technology, simplifying the power supply equipment and current control method; the modulation ring axial air duct enhances the heat dissipation effect of the modulation ring and its winding, thereby improving the load capacity of the motor.

[0054] Although the above describes the specific embodiments of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solutions disclosed in the present invention without the need for creative work should be included in the scope of protection of the present invention.

Claims

1. A modulation ring structure of a magnetic gear composite permanent magnet motor, comprising an outer rotor yoke, an outer rotor permanent magnet, an inner rotor permanent magnet, an inner rotor yoke, and a plurality of modulation blocks evenly arranged between the outer rotor permanent magnet and the inner rotor permanent magnet, wherein the modulation blocks are provided with slots; characterized in that: Among the plurality of modulation blocks, the angle between the symmetry axis of a slot of one modulation block and the line connecting the central axis of the modulation block and the central axis of the modulation ring structure is 0°, and this modulation block is the first modulation block; the remaining modulation blocks are arranged in sequence with the first modulation block as a reference in a direction consistent with the rotation direction of the inner rotor, and are the second modulation block, the third modulation block... the nth modulation block. s modulation blocks; in each modulation block, any slot is selected as the reference slot for the installation angle of the modulation block, which is uniformly described as a marking slot. The installation rule of the remaining modulation blocks is as follows: taking the marking slots of all the remaining modulation blocks coincide with the marking slot of the first modulation block as a benchmark, the remaining modulation blocks are uniformly arranged between the outer rotor permanent magnet and the inner rotor permanent magnet after rotating around their respective central axes at a certain angle compared to the previous modulation block. The angle between the symmetry axis of the marking slot in each modulation block and the line connecting its central axis and the central axis of the modulation ring structure is Among them, p i is the number of pole pairs of the inner rotor, n s is the total number of modulation blocks, and m is the number of the modulation block.

2. The modulation ring structure of the magnetic gear composite permanent magnet motor according to claim 1 is characterized in that: The d-axis winding and q-axis winding of each modulation block rotate around their respective central axes at a certain angle relative to the previous modulation block and are arranged in corresponding slots, where the angle between the axis of the d-axis winding and the line connecting the central axis of the modulation block and the central axis of the modulation ring structure is The angle between the q-axis winding axis and the line connecting the central axis of the modulation block and the central axis of the modulation ring structure is 3. A magnetic gear composite permanent magnet motor, characterized in that: The invention comprises a modulation ring structure of a magnetic gear composite permanent magnet motor as claimed in claim 1 or 2.

4. The magnetic gear composite permanent magnet motor according to claim 3, characterized in that: The modulation block winding constitutes the dual-axis modulation surround group of the magnetic gear compound permanent magnet motor. The d-axis modulation surround group of the magnetic gear compound permanent magnet motor is formed by connecting the d-axis windings of all modulation blocks end to end in series. The q-axis modulation surround group of the magnetic gear compound permanent magnet motor is formed by connecting the q-axis windings of all modulation blocks end to end in series.

5. The magnetic gear composite permanent magnet motor according to claim 4, characterized in that: The dual-axis modulation surround group is powered by a two-phase AC power supply. The amplitude of the power supply current of the d-axis and q-axis modulation surround groups is equal, the phase difference is 90°, and the power supply current frequency is It is also equal to where n i and n o are the speeds of the inner and outer rotors, respectively, p i and p o are the pole pairs of the inner rotor and outer rotor respectively.

6. The magnetic gear composite permanent magnet motor according to claim 5, characterized in that: The space between the modulation blocks is used as an air duct, and air flow is introduced into the air duct along the axial direction of the motor to provide cooling conditions for the modulation ring and its biaxial winding.

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