Electric motor with composite structure

Abstract

Provided is an electric motor with a composite structure, the electric motor comprising a shell (1), and a first end cap (2) and a second end cap (3) which are arranged at two ends of the shell (1), wherein a rotating shaft (7) is rotatably fixed in the shell (1), two ends of the rotating shaft (7) being rotatably connected to the first end cap (2) and the second end cap (3), respectively; from the rotating shaft (7), a wound inner rotor (4), a permanent magnet inner rotor (5), an inner stator (6), a magnetic isolation ring (17), an outer stator (8) and an outer rotor (9) are arranged in sequence in a direction away from the rotating shaft (7), the wound inner rotor (4) being fixedly connected to the rotating shaft (7), the permanent magnet inner rotor (5) and the outer rotor (9) being rotatably fixed in the shell (1), and the inner stator (6) and the outer stator (8) being fixed in the shell (1); and the outer rotor (9) and the outer stator (8) are both of a salient-pole structure, outer stator permanent magnets (21) being provided in salient-pole core teeth of the outer stator (8).

Description

A composite structure motor Technical Field

[0001] The present invention relates to the field of hybrid power drive systems, and in particular to a composite structure motor. Background Art

[0002] Today, the world faces energy supply challenges in production and daily life. The development of highly efficient drive motors is urgently needed for applications such as new energy vehicles replacing traditional fuel vehicles and high-power hybrid agricultural aircraft. However, existing powertrain technologies remain constrained by bottlenecks in battery technology. Against this backdrop, hybrid electric drive remains a key technological development path. To meet the miniaturization and lightweight requirements of hybrid drive equipment, streamlining the powertrain system, reducing system complexity, and improving reliability are key research areas in the hybrid drive field.

[0003] Currently, hybrid electric vehicles typically use two motors: one coaxial with the internal combustion engine, serving as a generator, and the other connected to the load, providing output power. However, this hybrid electric motor structure is susceptible to structural limitations, failing to maintain high power density and efficiency, and the motor structure needs to be streamlined and optimized. Furthermore, most current hybrid electric motor structures require improvements by replacing the planetary gears in hybrid drive systems with the motor itself, or operating as a continuously variable transmission, to achieve low-speed, high-torque performance. However, most existing motors cannot achieve this through structural improvements alone. Therefore, optimizing the motor's structure to improve the drive performance of hybrid devices is one approach to addressing these challenges.

[0004] Summary of the Invention

[0005] To solve the problems existing in the background technology, the present invention proposes a composite structure motor, including a housing and a first end cover and a second end cover arranged at both ends of the housing. A rotating shaft is rotatably fixed in the housing, and a wound inner rotor, a permanent magnet inner rotor, an inner stator, a magnetic isolation ring, an outer stator, and an outer rotor are arranged in sequence from the rotating shaft to the direction away from the rotating shaft. The wound inner rotor is fixedly connected to the rotating shaft, and the inner and outer stators are fixed in the housing.

[0006] The permanent magnet inner rotor comprises a permanent magnet inner rotor permanent magnet and a permanent magnet inner rotor bracket. The permanent magnet inner rotor permanent magnet is fixed on the permanent magnet inner rotor bracket. The permanent magnet inner rotor permanent magnet is located between the wound inner rotor and the inner stator. One end of the permanent magnet inner rotor bracket is rotatably fixed to the first end cover, and the other end of the permanent magnet inner rotor bracket is rotatably fixed to the rotating shaft.

[0007] The outer rotor is fixed on the outer rotor bracket, one end of the outer rotor bracket is rotatably fixed on the first end cover, and the two ends of the rotating shaft are rotatably fixed on the first end cover and the second end cover respectively;

[0008] The outer rotor and the outer stator are both salient pole structures, the outer stator comprises outer stator salient pole core teeth and outer stator permanent magnets, and the outer stator permanent magnets are installed in the outer stator salient pole core teeth;

[0009] The outer stator and outer rotor constitute a flux switching outer motor, the inner stator, the permanent magnet inner rotor and the wound inner rotor constitute a hybrid excitation induction inner motor, and the flux switching outer motor and the hybrid excitation induction inner motor realize bidirectional energy flow through the power supply.

[0010] Preferably, the outer rotor bracket is rotatably connected to the first end cover through the end cover bearing and the first bearing, the permanent magnet inner rotor bracket is rotatably connected to the rotating shaft through the first bearing and the second bearing on the side close to the first end cover, and the permanent magnet inner rotor bracket is rotatably connected to the rotating shaft through the third bearing on the side close to the second end cover. One end of the rotating shaft is embedded in the second bearing, and the other end of the rotating shaft is rotatably connected to the second end cover through another end cover bearing.

[0011] Preferably, the power supply includes a battery, a rotor rectifier and reversal device, and a stator rectifier and inversion device, the inner stator and the outer stator are respectively connected to the stator rectifier and inversion device, the wound inner rotor is connected to the rotor rectifier and inversion device, and the stator rectifier and inversion device and the rotor rectifier and inversion device are both connected to the battery.

[0012] Preferably, the wound inner rotor includes a wound inner rotor core and a wound inner rotor winding, the wound inner rotor winding is connected to the rotor rectifier inverter device through brushes and slip rings in sequence, and the wound inner rotor winding is a three-phase symmetrical AC winding.

[0013] Preferably, the inner stator includes an inner stator core and an inner stator winding, the inner stator winding is a three-phase symmetrical AC winding, and the inner stator winding is connected to the stator rectifier inverter device.

[0014] Preferably, the permanent magnet inner rotor, the inner stator and the wound inner rotor have the same number of poles, and the positions of the permanent magnets of the permanent magnet inner rotor correspond to the positions of the windings of the wound inner rotor.

[0015] Preferably, the magnetization directions of the external stator permanent magnets installed in two adjacent external stator salient pole core teeth in the external stator are opposite, and a coil is installed across each external stator salient pole core tooth to form an external stator winding, and the external stator winding is connected to the stator rectifier inverter device.

[0016] Preferably, the outer rotor is composed of an outer rotor iron core and outer rotor salient pole teeth, and the outer rotor salient pole teeth are opposite to the outer stator salient pole iron core teeth.

[0017] Preferably, a first air gap is provided between the wound inner rotor and the permanent magnet inner rotor, a second air gap is provided between the permanent magnet inner rotor and the inner stator, and a third air gap is provided between the outer stator and the outer rotor.

[0018] Preferably, the permanent magnets of the permanent magnet inner rotor are of a surface-mounted structure and are evenly arranged along the circumferential direction. The permanent magnets of the permanent magnet inner rotor are radially magnetized and adjacent permanent magnets are magnetized in opposite directions.

[0019] A working method of a composite structure motor, wherein the rotating shaft and the second end cover connecting end are connected to a prime mover, and the outer rotor bracket and the first end cover connecting end are connected to a load. During operation, the prime mover transmits mechanical energy to a wound inner rotor. After the wound inner rotor is energized, it rotates at a certain speed driven by the prime mover, inducing an electromotive force in the inner stator winding. The magnetic flux turns generated in the first air gap by the permanent magnets of the permanent magnet inner rotor and the wound inner rotor winding with alternating current also induce an electromotive force in the inner stator winding, realizing the power generation function of the hybrid excitation induction inner motor. The wound inner rotor is fixed on the rotating shaft, so the prime mover and the wound inner rotor are equivalent to being directly connected. The hybrid excitation induction inner motor generally operates in a power generation state and transmits electrical energy to a battery for storage through a stator rectifier inverter device; the battery supplies power to the outer stator winding through the stator rectifier inverter device, thereby driving the flux switching outer motor to perform electric operation.

[0020] The beneficial effects of the present invention are:

[0021] 1. The present invention combines the generator and motor in a hybrid drive system into a composite motor, simplifying the integration of traditional hybrid drive motors. Furthermore, the present invention uses mixed excitation of the permanent magnet inner rotor and the wound inner rotor, reducing electrical wear on the slip rings and brushes, lowering the excitation capacity of the rotor rectifier inverter device, and improving the power factor and efficiency of the motor.

[0022] 2. Both the outer rotor and the outer stator are salient pole structures, and the outer rotor is not equipped with permanent magnets and windings. It has a simple structure, is easy to install, and is easy to dissipate heat. The outer rotor can be directly connected to the load and directly drive the load without a reduction device, which improves the system's integrated energy transmission efficiency, reduces the system's maintenance workload and failure rate, and thus increases the reliability of the hybrid system's operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG1 is a schematic diagram of the overall structure of the present invention;

[0024] FIG2 is a schematic diagram of the axial cross-sectional structure of the present invention.

[0025] Numbers in the figure: 1. casing; 2. first end cover; 3. second end cover; 4. wound inner rotor; 5. permanent magnet inner rotor; 6. inner stator; 7. rotating shaft; 8. outer stator; 9. outer rotor; 10. first bearing; 11. wound inner rotor winding; 12. permanent magnet inner rotor; 13. end cover bearing; 14. brush; 15. slip ring; 16. stator bracket; 17. magnetic isolation ring; 18. inner stator winding; 19. outer rotor bracket; 20. outer stator winding; 21. outer stator permanent magnet; 22. first air gap; 23. permanent magnet inner rotor bracket; 24. second air gap; 25. second bearing; 26. third air gap; 27. third bearing; 28. rotor rectifier inverter; 29. ​​stator rectifier inverter; 30. battery. DETAILED DESCRIPTION

[0026] In order to make the present invention clearer and more understandable, the technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the given embodiment is only one implementation method and does not represent all embodiments.

[0027] In this article, terms such as "inside" and "outside" are established based on the positional relationships shown in the drawings. Depending on the different drawings, the corresponding positional relationships may also change accordingly. Therefore, they cannot be understood as absolute limitations on the scope of protection.

[0028] 1 and 2 , a composite structure motor includes a housing 1 and a first end cover 2 and a second end cover 3 provided at both ends of the housing 1. A rotating shaft 7 is rotatably fixed within the housing 1. A wound inner rotor 4, a permanent magnet inner rotor 5, an inner stator 6, a magnetic isolation ring 17, an outer stator 8, and an outer rotor 9 are sequentially provided from the rotating shaft 7 in a direction away from the rotating shaft 7. The wound inner rotor 4 is fixedly connected to the rotating shaft 7, and the inner stator 6 and the outer stator 8 are fixed within the housing 1.

[0029] The permanent magnet inner rotor 5 includes a permanent magnet inner rotor permanent magnet 12 and a permanent magnet inner rotor bracket 23. The permanent magnet inner rotor permanent magnet 12 is fixed on the permanent magnet inner rotor bracket 23. The permanent magnet inner rotor permanent magnet 12 is located between the wound inner rotor 4 and the inner stator 6. One end of the permanent magnet inner rotor bracket 23 is rotatably fixed to the first end cover 2, and the other end of the permanent magnet inner rotor bracket 23 is rotatably fixed to the rotating shaft 7. More specifically, the inner stator 6 and the outer stator 8 are each fixed in the casing 1 through a stator bracket 16, that is, one end of the stator bracket 16 is fixedly connected to the second end cover 3, and the other end of the stator bracket 16 is located in the casing 1. The inner stator 6 and the outer stator 8 are fixed to one end of the stator bracket 16 located in the casing 1.

[0030] The outer rotor 9 is fixed on the outer rotor bracket 19, one end of the outer rotor bracket 19 is rotatably fixed to the first end cover 2, and the two ends of the rotating shaft 7 are rotatably fixed to the first end cover 2 and the second end cover 3 respectively;

[0031] The outer rotor 9 and the outer stator 8 are both salient pole structures. The outer stator 8 includes outer stator salient pole core teeth and outer stator permanent magnets 21. The outer stator permanent magnets 21 are installed in the outer stator salient pole core teeth.

[0032] The outer stator 8 and outer rotor 9 constitute a flux switching outer motor, and the inner stator 6, permanent magnet inner rotor 5, and wound inner rotor 4 constitute a hybrid excitation induction inner motor. The flux switching outer motor and the hybrid excitation induction inner motor achieve bidirectional energy flow through a power supply. Specifically, the power supply includes a battery 30, a rotor rectifier and reversing device 28, and a stator rectifier and inverter device 29. The inner stator 6 and outer stator 8 are respectively connected to the stator rectifier and inverter device 29, and the wound inner rotor 4 is connected to the rotor rectifier and reversing device 28. The stator rectifier and inverter device 29 and the rotor rectifier and reversing device 28 are both connected to the battery 30.

[0033] Specifically, the center lines of the wound inner rotor 4, the permanent magnet inner rotor 5, the inner stator 6, the outer stator 8, and the outer rotor 9 are on the same straight line; the rotating shaft 7 is fixed to the wound inner rotor 4, and one end of the rotating shaft 7 close to the second end cover 3 is directly connected to the prime mover and is driven by the prime mover. The outer rotor bracket 19 close to the first end cover 2 is the output end, and the output end of the outer rotor bracket 19 directly drags the load.

[0034] Specifically, the outer rotor bracket 19 is rotatably connected to the first end cover 2 through the end cover bearing 13 and the first bearing 10. The permanent magnet inner rotor bracket 23 is rotatably connected to the rotating shaft 7 through the first bearing 10 and the second bearing 25 on the side close to the first end cover 2. The permanent magnet inner rotor bracket 23 is rotatably connected to the rotating shaft 7 through the third bearing 27 on the side close to the second end cover 3. One end of the rotating shaft 7 is embedded in the second bearing 25, and the other end of the rotating shaft 7 is rotatably connected to the second end cover 3 through another end cover bearing 13.

[0035] Specifically, the wound inner rotor 4 includes a wound inner rotor core and a wound inner rotor winding 11. The wound inner rotor winding 11 is connected to the rotor rectifier inverter device 28 through brushes 14 and slip rings 15 in sequence, and the rotor rectifier inverter device 28 provides excitation power. The wound inner rotor winding 11 is a three-phase symmetrical AC winding.

[0036] Specifically, the inner stator 6 includes an inner stator core and an inner stator winding 18 . The inner stator winding 18 is a three-phase symmetrical AC winding. The inner stator winding 18 is connected to a stator rectifier inverter device 29 .

[0037] Specifically, the permanent magnet inner rotor 5, the inner stator 6 and the wound inner rotor 4 have the same number of poles. The permanent magnet inner rotor 5 is made of magnetic conductive material. The position of the permanent magnet 12 of the permanent magnet inner rotor corresponds to the position of the wound inner rotor winding 11. The permanent magnet 12 of the permanent magnet inner rotor is radially magnetized and can improve the air gap magnetic density of the motor.

[0038] Specifically, the magnetization directions of the external stator permanent magnets 21 installed in two adjacent external stator salient pole core teeth in the external stator 8 are opposite, and a coil is installed across each external stator salient pole core tooth to form an external stator winding 20; the external stator winding 20 is connected to the stator rectifier inverter device 29.

[0039] Specifically, the outer rotor 9 is composed of an outer rotor core and outer rotor salient pole teeth, and the outer rotor salient pole teeth are opposite to the outer stator salient pole core teeth.

[0040] Specifically, a first air gap 22 is defined between the wound inner rotor 4 and the permanent magnet inner rotor 5, a second air gap 24 is defined between the permanent magnet inner rotor 5 and the inner stator 6, and a third air gap 26 is defined between the outer stator 8 and the outer rotor 9. More specifically, the second air gap 24 is located between the permanent magnet inner rotor permanent magnets 12 and the inner stator 6. The magnetic flux generated by the permanent magnet inner rotor permanent magnets 12 and the magnetic flux turns generated in the first air gap 22 by the wound inner rotor windings 11 fed with an AC excitation power supply simultaneously combine with the magnetic field turns generated by the three-phase windings of the inner stator, achieving hybrid excitation.

[0041] Specifically, the permanent magnets 12 of the permanent magnet inner rotor are of a surface-mounted structure and are evenly arranged along the circumferential direction. The permanent magnets 12 of the permanent magnet inner rotor are magnetized in the radial direction, and adjacent permanent magnets are magnetized in opposite directions.

[0042] Specifically, by changing the structure of the motor body in the hybrid excitation induction, the capacity of the rotor rectifier inverter 28 is reduced, which not only helps to reduce the weight of the motor drive system, but also helps to save drive space.

[0043] The hybrid excitation induction motor can reduce the mechanical impact during motor startup and variable speed operation, while reducing the excitation capacity of the rotor rectifier inverter device 28. Moreover, the present invention adopts an outer rotor structure and can directly drive the load without a reduction device.

[0044] The permanent magnet inner rotor 5 operates at no load, its primary function being to provide a permanent magnet excitation magnetic field. The number of poles in the permanent magnet inner rotor 5 is the same as that of the inner stator 6 and the wound inner rotor 4. The wound inner rotor 4 is mounted within the permanent magnet inner rotor 5 with a first air gap 22 between it and the permanent magnet inner rotor 5. The wound inner rotor 4 comprises an inner rotor core and a wound inner rotor winding 11. The wound inner rotor 4 is fixedly connected to the rotating shaft 7. Both the inner stator winding 18 and the wound inner rotor 4 are three-phase symmetrical AC windings.

[0045] The AC and permanent magnet hybrid excitation structure of the present invention can improve the air gap magnetic density of the motor. At the same time, the AC and permanent magnet hybrid excitation increases the air gap surface area and improves the torque density of the motor.

[0046] A method for operating a composite structure motor, wherein the connecting end of the rotating shaft 7 and the second end cover 3 is connected to a prime mover, and the connecting end of the outer rotor bracket 19 and the first end cover 2 is connected to a load. During operation, the prime mover transmits mechanical energy to the wound inner rotor 4. After being energized, the wound inner rotor 4 rotates at a certain speed driven by the prime mover, inducing an electromotive force in the inner stator winding 18. The magnetic flux turns generated in the first air gap 22 by the permanent magnet 12 of the permanent magnet inner rotor and the wound inner rotor winding 11 to which alternating current is applied will also induce an electromotive force in the inner stator winding 18, thereby realizing the power generation function of the hybrid excitation induction inner motor.

[0047] The prime mover is directly connected to the wound inner rotor 4. The hybrid excitation induction inner motor generally operates in a power generation state and transmits electrical energy to the battery 30 for storage through the stator rectifier inverter device 29; the battery 30 supplies power to the outer stator winding 20 through the stator rectifier inverter device 29, thereby driving the magnetic flux switching outer motor for electric operation.

[0048] Since the flux switching external motor has the characteristics of low speed and high torque, no reduction gear is required between the flux switching external motor and the load transmission shaft, which simplifies the drive system while reducing costs and increasing reliability.

[0049] The above embodiments merely illustrate the basic principles and features of the present invention and are not intended to be limiting. It should be understood that various changes and modifications may be made to the present invention by those skilled in the art without departing from the spirit and scope of the present invention, and such changes and modifications are intended to fall within the scope of the present invention as claimed. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A composite structure motor, characterized in that: The invention comprises a casing (1) and a first end cover (2) and a second end cover (3) arranged at two ends of the casing (1); a rotating shaft (7) is rotatably fixed in the casing (1); a winding inner rotor (4), a permanent magnet inner rotor (5), an inner stator (6), a magnetic isolation ring (17), an outer stator (8) and an outer rotor (9) are arranged in sequence from the rotating shaft (7) to a direction away from the rotating shaft (7); the winding inner rotor (4) is fixedly connected to the rotating shaft (7); and the inner stator (6) and the outer stator (8) are fixed in the casing (1); The permanent magnet inner rotor (5) comprises a permanent magnet inner rotor permanent magnet (12) and a permanent magnet inner rotor bracket (23); the permanent magnet inner rotor permanent magnet (12) is fixed on the permanent magnet inner rotor bracket (23); the permanent magnet inner rotor permanent magnet (12) is located between the wound inner rotor (4) and the inner stator (6); one end of the permanent magnet inner rotor bracket (23) is rotatably fixed on the first end cover (2); and the other end of the permanent magnet inner rotor bracket (23) is rotatably fixed on the rotating shaft (7); The outer rotor (9) is fixed on the outer rotor bracket (19), one end of the outer rotor bracket (19) is rotatably fixed on the first end cover (2), and the two ends of the rotating shaft (7) are rotatably fixed on the first end cover (2) and the second end cover (3) respectively; The outer rotor (9) and the outer stator (8) are both salient pole structures, the outer stator (8) comprises outer stator salient pole core teeth and outer stator permanent magnets (21), and the outer stator permanent magnets (21) are installed in the outer stator salient pole core teeth; The outer stator (8) and the outer rotor (9) constitute a flux switching outer motor, and the inner stator (6), the permanent magnet inner rotor (5) and the wound inner rotor (4) constitute a hybrid excitation induction inner motor. The flux switching outer motor and the hybrid excitation induction inner motor realize bidirectional energy flow through a power supply.

2. A composite structure motor according to claim 1, characterized in that: The outer rotor support (19) is rotatably connected to the first end cover (2) via an end cover bearing (13) and a first bearing (10); the permanent magnet inner rotor support (23) is rotatably connected to the rotating shaft (7) via a first bearing (10) and a second bearing (25) on a side close to the first end cover (2); the permanent magnet inner rotor support (23) is rotatably connected to the rotating shaft (7) via a third bearing (27) on a side close to the second end cover (3); one end of the rotating shaft (7) is embedded in the second bearing (25), and the other end of the rotating shaft (7) is rotatably connected to the second end cover (3) via another end cover bearing (13).

3. The composite structure motor according to claim 1, characterized in that: The power source comprises a storage battery (30), a rotor rectifying and reversing device (28) and a stator rectifying and inverting device (29); the inner stator (6) and the outer stator (8) are respectively connected to the stator rectifying and inverting device (29); the wound inner rotor (4) is connected to the rotor rectifying and inverting device (28); and the stator rectifying and inverting device (29) and the rotor rectifying and inverting device (28) are both connected to the storage battery (30).

4. The composite structure motor according to claim 3, characterized in that: The wound inner rotor (4) comprises a wound inner rotor core and a wound inner rotor winding (11), wherein the wound inner rotor winding (11) is connected to a rotor rectification and reversing device (28) via a brush (14) and a slip ring (15) in sequence, and the wound inner rotor winding (11) is a three-phase symmetrical AC winding.

5. The composite structure motor according to claim 4, characterized in that: The permanent magnet inner rotor (5), the inner stator (6) and the wound inner rotor (4) have the same number of poles, and the position of the permanent magnet (12) of the permanent magnet inner rotor corresponds to the position of the wound inner rotor winding (11).

6. The composite structure motor according to claim 3, characterized in that: The inner stator (6) comprises an inner stator iron core and an inner stator winding (18). The inner stator winding (18) is a three-phase symmetrical AC winding. The inner stator winding (18) is connected to a stator rectifier inverter device (29).

7. The composite structure motor according to claim 3, characterized in that: The external stator permanent magnets (21) installed in two adjacent external stator salient pole core teeth in the external stator (8) have opposite magnetization directions, and a coil is installed across each external stator salient pole core tooth to form an external stator winding (20), and the external stator winding (20) is connected to a stator rectifier inverter device (29).

8. The composite structure motor according to claim 1, characterized in that: The outer rotor (9) is composed of an outer rotor iron core and outer rotor salient pole teeth, and the outer rotor salient pole teeth are opposite to the outer stator salient pole iron core teeth.

9. The composite structure motor according to claim 1, characterized in that: A first air gap (22) is provided between the wound inner rotor (4) and the permanent magnet inner rotor (5), a second air gap (24) is provided between the permanent magnet inner rotor (5) and the inner stator (6), and a third air gap (26) is provided between the outer stator (8) and the outer rotor (9).

10. The composite structure motor according to claim 1, characterized in that: The permanent magnet inner rotor permanent magnets (12) are of a surface-mounted structure and are evenly arranged in a circumferential direction. The permanent magnet inner rotor permanent magnets (12) are radially magnetized, and adjacent permanent magnet inner rotor permanent magnets (12) are magnetized in opposite directions.

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