A water-cooled electromagnetic drive motor with three-dimensional winding of composite magnetic flux in a special-shaped slot

Abstract

This invention relates to the field of electromagnetic drive technology, and more particularly to a water-cooled electromagnetic drive motor with a stacked, irregularly shaped slotted composite flux three-dimensional winding, comprising: a rotor assembly including an axial rotor for generating axial flux and a radial rotor disposed at the outer end of the axial rotor for generating radial flux; a stator assembly including a three-dimensional winding for interacting with the composite flux generated by the axial rotor and the radial rotor respectively, a radial stator core fitted with the three-dimensional winding, and an axial stator core disposed at one end of the radial stator core and fitted with the three-dimensional winding; wherein, the radial stator core has a plurality of first irregularly shaped mounting slots arranged annularly for mounting the three-dimensional winding, and the axial stator core has a plurality of second irregularly shaped mounting slots arranged annularly for mounting the three-dimensional winding. This invention improves the torque density of the electromagnetic drive.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic drive technology, and in particular to a water-cooled electromagnetic drive motor with a stacked, irregularly shaped slot composite flux three-dimensional winding. Background Technology

[0002] Improving power density is crucial for electromagnetic drives in electric propulsion, directly determining the payload capacity and operational performance of electric aircraft. Within a limited volume or system mass, increasing power density can primarily be achieved by increasing system speed or output torque. However, electric aircraft generally employ a more efficient direct-drive motor-propeller configuration. Therefore, to avoid propeller stall due to excessively high propeller speeds, the electric propulsion motor speed is typically relatively low, such as 1000 rpm. Thus, increasing the torque density of the electromagnetic drive is key to improving the output performance of the electromagnetic drive in electric propulsion.

[0003] Currently, permanent magnet synchronous motors (PMSMs) offer higher power density and efficiency compared to other types of motors, such as asynchronous motors, and are widely used in electric propulsion motors. PMSMs can be mainly classified into radial flux electromagnetic drives and axial flux electromagnetic drives based on the direction of the main magnetic flux chain emanating from the rotor poles through the windings. According to the sizing functions of radial and axial flux motors, high-speed, slender radial flux motors and low-speed, flat axial flux motors have higher torque / power volume density. However, to fully utilize the advantages of radial and axial flux electromagnetic drives, the former requires a longer axial length, while the latter requires a larger radial dimension. For electric propulsion applications or other situations with strict dimensional constraints on both axial and radial space, it is difficult to achieve the performance of traditional single flux electromagnetic drives.

[0004] Therefore, improving the torque density of electromagnetic drives (motors) under strict axial and radial dimension constraints is extremely important. The above analysis mainly focused on the system space utilization from the perspective of magnetic flux distribution, or the relative positions of the stator and rotor. However, good system heat dissipation characteristics are also a crucial factor in improving the torque density of electromagnetic drives. Traditional motor heat dissipation methods mainly include two categories: forced air cooling and water jacket cooling. The insulation varnish of the motor stator windings and the gaps between the wires are often the main factors limiting the motor's heat dissipation capacity. In other words, in addition to good air or water cooling conditions, it is also necessary to quickly dissipate the heat flow within the windings to effectively reduce the maximum temperature of the motor system.

[0005] Chinese patent application publication number CN118337015A discloses a novel axial-radial multi-sided excitation permanent magnet direct drive motor, relating to the field of permanent magnet motors. This invention aims to meet the performance requirements of low-speed, high-torque direct drive motors for electric vehicles. The motor designed in this invention is a high torque density permanent magnet synchronous motor, including an intermediate stator, an axial rotor, a radial rotor, a support shaft, and bearings. The stator is coaxially located inside the radial rotor and includes a stator core and an armature winding. The radial rotor adopts an external rotor structure, including a rotor core and rotor permanent magnets, with the permanent magnets installed in an alternating pole configuration. Axial rotors are provided on both the left and right sides along the axial direction, coaxially and parallel to the stator, with an air gap between them. An air gap also exists between the stator and the radial rotor. The support shaft serves to support and fix the stator. Bearings are added between the support shaft and the axial rotors, allowing the axial rotors to rotate while the support shaft remains stationary. The axial rotors and radial rotors are connected by a mechanical structure made of non-magnetic material to achieve superposition of rotor output. The armature winding is wound on the stator in the form of a ring winding, so that a single winding can simultaneously link with both the radial and axial magnetic fields. This invention employs a composite motor structure that combines axial and radial magnetic flux, which can achieve high electromagnetic space utilization and high torque density, thereby improving the motor's torque output capability and meeting the industrial application requirements for low-speed, high-torque direct-drive motors.

[0006] The existing technology also has the following problems: under the limited space constraints, the slot area of ​​the axial and radial stator slots of the existing composite flux electromagnetic drive is inconsistent, and the magnetic permeability and saturation magnetic density of the stator core made of SMC material are low. In addition, there is mutual interference between the end windings of multiple sets of windings, which limits the improvement of electromagnetic drive torque density. Summary of the Invention

[0007] To address these issues, the present invention provides a stacked irregular slot composite flux three-dimensional winding water-cooled electromagnetic drive motor, which overcomes the problems in the prior art where, under limited space constraints, the slot areas of the axial and radial stator slots are inconsistent, the stator core uses SMC material with low permeability and saturation magnetic density, and there is mutual interference between the end windings of multiple sets of windings, thus limiting the improvement of electromagnetic drive torque density.

[0008] To achieve the above objectives, the present invention provides a water-cooled electromagnetic drive motor with a stacked, irregularly shaped slot composite flux three-dimensional winding, comprising:

[0009] A rotor assembly for generating a composite magnetic flux includes an axial rotor for generating an axial magnetic flux and a radial rotor disposed at the outer end of the axial rotor for generating a radial magnetic flux.

[0010] A stator assembly, disposed inside the rotor assembly and connected to the rotor assembly via a connecting assembly, includes a three-dimensional winding for interacting with the composite magnetic flux generated by the axial rotor and the radial rotor respectively, a radial stator core fitted with the three-dimensional winding, and an axial stator core disposed at one end of the radial stator core and fitted with the three-dimensional winding.

[0011] A connecting assembly, which is connected to the rotor assembly and the stator assembly respectively, includes a rotating shaft disposed inside the rotor assembly and connected to an axial rotor support at one end, a pair of back-to-back angular contact ball bearings disposed at the inner end of the rotating shaft near the axial rotor support, and a deep groove ball bearing disposed at the end of the rotating shaft away from the axial rotor support.

[0012] A water jacket assembly for cooling the three-dimensional winding includes a water jacket shell embedded inside the radial stator core and a water jacket back cover fitted with the water jacket shell.

[0013] The radial stator core has a plurality of first irregularly shaped mounting slots arranged in a ring for mounting the three-dimensional winding, and the axial stator core has a plurality of second irregularly shaped mounting slots arranged in a ring for mounting the three-dimensional winding. The first irregularly shaped mounting slots and the second irregularly shaped mounting slots form an irregularly shaped slot configuration with the same slot area.

[0014] Furthermore, the radial stator core is made of silicon steel sheets stacked axially, and the axial stator core is made of silicon steel strip wound radially. The radial stator core and the axial stator core are connected by the connecting assembly to form an annular heat dissipation space.

[0015] Furthermore, the axial rotor includes an axial rotor support member for providing support, an axial rotor magnetic back iron disposed inside the axial rotor support member and connected to the axial rotor support member, and an axial rotor magnetic pole array disposed on the side of the axial rotor magnetic back iron away from the rotor support member. The axial rotor magnetic pole array is a fan-shaped surface-mounted radially alternating magnetized magnetic pole array, or a Halbach magnetic pole array without a rotor back iron.

[0016] Furthermore, the radial rotor includes a radial rotor support member for providing support, a radial rotor magnetic back iron disposed inside and connected to the radial rotor support member, and a radial rotor magnetic pole array disposed inside and fitted inside the radial rotor magnetic back iron. The radial rotor magnetic pole array is a fan-shaped surface-mount radial alternating magnetized magnetic pole array, or a Halbach magnetic pole array without a rotor back iron.

[0017] Furthermore, the radial rotor magnetic pole array is an irregularly shaped magnetic pole array based on the injection of a bottom arc fundamental wave and a square wave, used to generate radial magnetic flux.

[0018] Furthermore, the stator assembly also includes several types of cubic SMC orthogonal teeth that are respectively connected to the radial stator core and the axial stator core and are arranged circumferentially around the orthogonal portion.

[0019] Furthermore, the stator assembly also includes a stator core support embedded in the central hole of the water jacket housing to provide support for the radial stator core, a front bearing steel sleeve embedded inside the stator core support and in contact with the interior of the stator core support, a resolver mounting flange disposed at the end of the stator core support away from the front bearing steel sleeve, a rotary transformer mechanically connected to the resolver mounting flange for feedback of the rotor position of the electromagnetic drive, and an insulating end plate disposed at the radial stator core end away from the axial stator core and in contact with the radial stator core end.

[0020] Furthermore, the resolver can be a sensor that provides position feedback, or any other type of sensor that can provide a rotor position signal.

[0021] Furthermore, the axial cross-sectional shape of the first irregularly shaped mounting slot is trapezoidal, and the radial cross-sectional shape of the second irregularly shaped mounting slot is rectangular. The first and second irregularly shaped mounting slots form an irregularly shaped slot configuration with the same slot area, which can further increase the effective area for generating output torque through the interaction between the rotor permanent magnet and the winding, within the maximum system outer diameter limitation.

[0022] Furthermore, the rotor assembly also includes an output shaft connector disposed at the central through hole of the axial rotor support for connecting the output shaft.

[0023] Furthermore, the connecting assembly, which is connected to the rotor assembly and the stator assembly respectively, includes a rotating shaft disposed inside the rotor assembly and connected to one end of the axial rotor support, a pair of back-to-back angular contact ball bearings disposed at the inner end of the rotating shaft near the axial rotor support, and a deep groove ball bearing disposed at the end of the rotating shaft away from the axial rotor support.

[0024] The angular contact ball bearing and the deep groove ball bearing are respectively locked onto the rotating shaft by lock nuts.

[0025] Furthermore, the angular contact ball bearing is embedded inside the front bearing sleeve, and the deep groove ball bearing is embedded inside the stator core support.

[0026] Furthermore, the water jacket is disposed inside the radial stator core and is respectively attached to the inner wall of the radial stator core and the side wall of the axial stator core for cooling the three-dimensional winding. The water jacket includes a water jacket shell embedded inside the radial stator core and a water jacket back cover fitted with the water jacket shell. Several inlet and outlet water pipes are provided at the end of the water jacket back cover. Several baffles are provided inside the water jacket shell, which are welded and fixed to the inner wall of the water jacket shell to divide the longitudinal space of the water jacket shell into several connected cooling intervals.

[0027] The water jacket is a four-segment parallel water jacket, with a single circulating water channel formed inside the water jacket between two adjacent water jackets that are far apart from each other, or multiple segments of parallel water jackets.

[0028] Compared with existing technologies, the beneficial effects of this invention are that it combines the advantages of traditional single axial and radial magnetic flux through composite magnetic flux to achieve the maximum torque density of the system under relatively small axial and radial space constraints. The orthogonal parts of the radial and axial stators are connected by cubic SMC orthogonal teeth to maximize the utilization of the electromagnetic interaction space. The magnetically permeable cubic SMC orthogonal teeth interact with the orthogonal end windings of the three-dimensional windings, further improving the torque density of the electromagnetic drive.

[0029] In particular, the present invention uses a single set of windings for both axial and radial magnetic fluxes, which avoids mutual interference and space waste at the end windings of multiple sets of windings, thereby improving torque density.

[0030] In particular, the axial and radial stators of the composite flux electromagnetic drive of the present invention are used to carry axial and radial fluxes, respectively. Since the axial and radial fluxes share a set of three-dimensional windings, the axial and radial stator slots need to have the same slot area. In order to maximize the radial rotor lever arm corresponding to the radial flux while taking into account the characteristics of composite flux, the radial stator slots adopt trapezoidal slots and parallel tooth structure, while the axial stator slots adopt rectangular slots and trapezoidal tooth structure. The irregular slot configuration has a high space utilization rate and can further increase the effective area for generating output torque between the rotor permanent magnet and the winding under the maximum system outer diameter limit, thereby improving the torque density of the electromagnetic drive.

[0031] In particular, the present invention uses axially stacked and radially wound high-saturated silicon steel sheets to form the radial and axial portions of the stator core of the composite electromagnetic drive, respectively, thereby further increasing the magnetic load of the stator and rotor cores.

[0032] In particular, the present invention employs a four-segment parallel water jacket to cool the three-dimensional winding. Compared with a single inlet and outlet, the heat exchange path of the water-cooling medium is shorter, which effectively reduces the temperature rise of the water-cooling medium and the three-dimensional winding, and significantly improves the heat dissipation capacity of the electromagnetic drive. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the isometric structure of a water-cooled electromagnetic drive motor with a stacked irregular groove composite magnetic flux three-dimensional winding according to an embodiment of the present invention.

[0034] Figure 2 This is a schematic diagram of the reverse isometric structure of a water-cooled electromagnetic drive motor with a stacked irregular groove composite magnetic flux three-dimensional winding according to an embodiment of the present invention;

[0035] Figure 3 This is an exploded view of the electromagnetically driven rotor assembly according to an embodiment of the present invention;

[0036] Figure 4 This is an exploded view of the stator assembly of the electromagnetic drive according to an embodiment of the present invention;

[0037] Figure 5 This is a schematic diagram of the structure of the three-dimensional winding mounting slot according to an embodiment of the present invention;

[0038] Figure 6 This is a schematic diagram of the water jacket structure according to an embodiment of the present invention;

[0039] Figure 7 This is a schematic diagram of the structure of the annular winding according to an embodiment of the present invention;

[0040] Figure 8 This is a comparison diagram of the back electromotive forces between composite flux electromagnetic drive and single flux electromagnetic drive in an embodiment of the present invention;

[0041] Figure 9 This is a torque comparison diagram between composite flux electromagnetic drive and single flux electromagnetic drive in an embodiment of the present invention.

[0042] In the figure, 1-rotor assembly, 11-axial rotor, 111-axial rotor support, 112-axial rotor magnetic back iron, 113-axial rotor magnetic pole array, 12-radial rotor, 121-radial rotor support, 122-radial rotor magnetic back iron, 123-radial rotor magnetic pole array, 13-output shaft connector, 2-stator assembly, 21-L-shaped three-dimensional winding, 211-first irregular mounting slot, 212-second irregular mounting slot, 22 23-Radial stator core, 24-Axial stator core, 25-SMC orthogonal teeth, 26-Annular winding, 27-Stator core support, 28-Front bearing steel sleeve, 29-Resolver mounting flange, 20-Resolver, 3-Connecting assembly, 31-Insulating end plate, 32-Shaft, 33-Angular contact ball bearing, 34-Deep groove ball bearing, 45-Locking nut, 46-Water jacket, 47-Water jacket housing, 48-Water jacket rear cover, 49-Pipe, 40-Baffle. Detailed Implementation

[0043] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0044] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0045] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0046] Please see Figures 1-4 As shown, Figure 1 This is a schematic diagram of the isometric structure of a water-cooled electromagnetic drive motor with a stacked irregular groove composite magnetic flux three-dimensional winding according to an embodiment of the present invention. Figure 2 This is a schematic diagram of the reverse isometric structure of a water-cooled electromagnetic drive motor with a stacked irregular groove composite magnetic flux three-dimensional winding according to an embodiment of the present invention; Figure 3 This is an exploded view of the electromagnetically driven rotor assembly according to an embodiment of the present invention; Figure 4 This is an exploded view of the stator assembly of the electromagnetic drive according to an embodiment of the present invention;

[0047] This invention relates to a stacked, irregularly shaped slotted composite flux three-dimensional winding water-cooled electromagnetic drive motor, comprising:

[0048] The rotor assembly 1, which is used to generate a composite magnetic flux, includes an axial rotor 11 for generating an axial magnetic flux and a radial rotor 12 disposed at one end of the axial rotor 11 for generating a radial magnetic flux.

[0049] The stator assembly 2, which is disposed inside the rotor assembly 1 and connected to the rotor via the connecting assembly 3, includes a three-dimensional winding for interacting with the composite magnetic flux generated by the axial rotor 11 and the radial rotor 12 respectively, a radial stator core 22 for fitting and mounting the three-dimensional winding, and an axial stator core 23 disposed at one end of the radial stator core 22 and fitted with the three-dimensional winding.

[0050] Connection component 3 is connected to the rotor assembly 1 and the stator assembly 2 respectively;

[0051] The water jacket assembly 4 includes a water jacket shell 41 embedded inside the radial stator core 22 and a water jacket back cover 42 fitted with the water jacket shell 41.

[0052] In one embodiment of the present invention, the three-dimensional winding is an L-shaped winding 21.

[0053] In another embodiment of the present invention, the three-dimensional winding is a ring winding 25.

[0054] Specifically, the radial stator core 22 is formed by stacking silicon steel sheets axially, and the axial stator core 23 is formed by winding silicon steel strip radially. The radial stator core 22 and the axial stator core 23 are connected by the connecting assembly to form an annular heat dissipation space.

[0055] Specifically, the composite flux electromagnetic drive of this invention mainly consists of a rotor assembly 1 and a stator assembly 2. The rotor and stator are connected by a shaft, a pair of back-to-back angular contact ball bearings 32 at the front, and a deep groove ball bearing 33 at the rear. The inner surface of the rotor's axial radial direction is surface-mounted with alternating N and S permanent magnets, and the outer surface of the stator is provided with a three-dimensional winding that surrounds the rotor axially, radially, and circumferentially. The magnetic pole array formed by the alternating N and S surface-mounted magnets generates a composite flux distributed axially and radially in the air gap of the electromagnetic drive. This flux interacts with the current flowing through the three-dimensional winding of the stator, generating a circumferential output torque. Compared to a single radial or axial flux electromagnetic drive, the proposed composite flux and three-dimensional winding electromagnetic configuration provides an additional axial or radial rotor for generating output torque within a limited volume.

[0056] For details, please continue reading Figure 3 As shown, the axial rotor 11 includes an axial rotor support 111 for providing support, an axial rotor magnetic back iron 112 disposed inside the axial rotor support 111 and connected to the axial rotor support 111, and an axial rotor magnetic pole array 113 disposed on the side of the axial rotor magnetic back iron 112 away from the rotor support 111. The axial rotor magnetic pole array 113 is a fan-shaped surface-mounted radially alternating magnetized magnetic pole array or a Halbach magnetic pole array without a rotor back iron.

[0057] The axial rotor support 111 and the axial rotor magnetic back iron 112 are both disk structures, and the axial rotor magnetic pole array 113 is a fan-shaped array of alternately magnetized magnetic poles used to generate axial magnetic flux.

[0058] Specifically, the rotor assembly 1 also includes an output shaft connector 13 disposed at the central through hole of the axial rotor support 111 for connecting the output shaft.

[0059] Specifically, the radial rotor 12 includes a radial rotor support 121 for providing support, a radial rotor magnetic back iron 122 disposed inside and connected to the radial rotor support 121, and a radial rotor magnetic pole array 123 disposed inside and fitted inside the radial rotor magnetic back iron 122. The radial rotor magnetic pole array 123 is a fan-shaped surface-mount radial alternating magnetized magnetic pole array or a Halbach magnetic pole array without a rotor back iron.

[0060] The radial rotor support 121 and the radial rotor magnetic back iron 122 are both ring structures, and the radial rotor magnetic pole array 123 is an irregular magnetic pole array based on the injection of bottom arc fundamental wave and square wave to generate radial magnetic flux.

[0061] Specifically, the connecting assembly 3 includes a rotating shaft 31 disposed inside the rotor assembly and connected to one end of the axial rotor support 111, a pair of back-to-back angular contact ball bearings 32 disposed at the inner end of the rotating shaft 31 near the axial rotor support 111, and a deep groove ball bearing 33 disposed at the end of the rotating shaft 31 away from the axial rotor support 111.

[0062] The angular contact ball bearing 32 and the deep groove ball bearing 33 are respectively locked on the rotating shaft 31 by a locking nut 34, and a corrugated spring 35 is also provided between the locking nut 34 and the deep groove ball bearing 33.

[0063] In this embodiment of the invention, the rotating shaft 31 is connected to the axial rotor 11 by bolts, and then the radial rotor 12 is connected to the axial rotor 11 by bolts to form the rotor assembly 1. The fan-shaped, axially alternating magnetized magnetic pole array 113 in the axial rotor 11 generates axial magnetic flux. This flux originates from the surface of the permanent magnet, passes through the air gap, the stator, and the rotor's magnetic back iron, forming an axial magnetic loop that interacts with the radial coil edges of the three-dimensional winding to generate output torque. Furthermore, the irregularly shaped magnetic pole array of the radial rotor 12 has its magnetization direction arranged alternately radially, forming radial magnetic flux at the radial air gap. In other words, the proposed rotor can simultaneously generate air gap magnetic flux distributed along both the axial and radial directions. This axial-radial magnetic flux, i.e., the composite magnetic flux, interacts with the current in the windings of the stator assembly 2 to generate output torque. To reduce the end windings, this invention uses a fractional-slot concentrated winding, which generates a large number of high-order harmonic magnetic fields on the rotor side. The frequency of these high-order harmonic magnetic fields is proportional to the number of rotor pole pairs and the rotational speed; the higher the frequency, the greater the rotor eddy current losses. Therefore, in order to simultaneously accommodate both a small harmonic frequency and a large magnetic load, a 24-slot, 20-pole winding is adopted.

[0064] Specifically, traditional radial magnetic pole arrays are mostly tile-shaped arrays with uniform thickness in the radial direction. However, this shape of magnetic pole is prone to generating large high-order magnetic field harmonics with a large radial rotor size and a small number of pole pairs, resulting in large stator eddy current losses and torque ripples. Therefore, in order to reduce the eddy current losses and torque pulsations caused by the radial rotor 12, this design adopts an irregularly shaped bottom arc-injected magnetic pole array. This magnetic pole array can provide a larger effective air gap magnetic flux density while reducing the content of high-order harmonics.

[0065] For details, please continue reading Figure 4 As shown, the stator assembly 2 also includes a plurality of SMC orthogonal teeth 24 that are connected to the radial stator core 22 and the axial stator core 23 respectively and are arranged circumferentially; a stator core support member 26 that is embedded in the central hole of the water jacket 41 to provide support for the radial stator core 22; a front bearing steel sleeve 27 that is embedded inside the stator core support member 26 and fits against the interior of the stator core support member 26; a resolver mounting flange 28 that is disposed at the end of the stator core support member 26 away from the front bearing steel sleeve 27; a rotary transformer 29 that is mechanically connected to the resolver mounting flange 28 for feedback of the rotor position of the electromagnetic drive; and an insulating end plate 30 that is disposed at the end of the radial stator core 22 away from the axial stator core 23 and fits against the end of the radial stator core 22.

[0066] In this embodiment of the invention, the rotary transformer 29 is a sensor that provides position feedback, or any other type of sensor that can provide rotor position signals.

[0067] In this embodiment of the invention, the angular contact ball bearing 32 is embedded inside the front bearing sleeve 27, and the deep groove ball bearing 33 is embedded inside the stator core support 26.

[0068] Among them, a pair of angular contact ball bearings 32 are arranged back to back in the front bearing steel sleeve 27, so that when the rotor assembly 1 rotates after the rotor assembly 1 and the stator assembly 2 form a composite magnetic flux, the rotating shaft 31 provides support for the rotor assembly 1 and drives the rotating shaft to rotate in the stator assembly 2.

[0069] Please see Figure 5 As shown, Figure 5 This is a schematic diagram of the structure of the three-dimensional winding mounting slot according to an embodiment of the present invention;

[0070] Specifically, the radial stator core 22 has a plurality of first irregularly shaped mounting slots 211 arranged in a ring for mounting the three-dimensional windings, and the axial stator core 23 has a plurality of second irregularly shaped mounting slots 212 arranged in a ring for mounting the three-dimensional windings. The axes of the first irregularly shaped mounting slots 211 and the second irregularly shaped mounting slots 212 are perpendicular. The axial cross-sectional shape of the first irregularly shaped mounting slot 211 is trapezoidal, and the radial cross-sectional shape of the second irregularly shaped mounting slot 212 is rectangular. The first irregularly shaped mounting slots and the second irregularly shaped mounting slots form an irregularly shaped slot configuration with the same slot area. This irregularly shaped slot configuration has a high space utilization rate and can further increase the effective area for generating output torque through the interaction between the rotor permanent magnet and the windings under the maximum system outer diameter limit, thereby improving the torque density of the electromagnetic drive.

[0071] Specifically, since the radial magnetic flux generated by the radial rotor 12 does not change along the radial direction, the radial stator core 22 in this embodiment of the invention adopts the following... Figure 5 The trapezoidal slot and parallel tooth structure shown in (a) are as follows. Conversely, the axial magnetic flux generated by the sector magnetic poles of the axial rotor increases continuously outward along the radius. Therefore, in this embodiment of the invention, the axial stator core 23 adopts the following... Figure 5 The rectangular slot and trapezoidal tooth structure shown in (a) constitutes the irregular slot configuration. Compared to the traditional configuration where both the axial and radial slots are rectangular, this irregular slot configuration allows the axial rotor 11 to have a larger effective electromagnetic area. Figure 5 As shown in (b), for the same axial and radial stator slot area, a rectangular slot requires a larger radial length. Therefore, when the maximum outer diameter of the electromagnetic drive is fixed, it will inevitably cause the axial stator and rotor to shift radially inward, thereby reducing the effective cross-sectional area of ​​the axial sector permanent magnet emission flux and the output torque of the composite flux electromagnetic drive.

[0072] Specifically, by employing SMC orthogonal teeth 24, the present invention can further utilize the end windings to improve the torque density of electromagnetic drive. Without the magnetically conductive SMC orthogonal teeth 24, the orthogonal end windings of the three-dimensional winding would be placed in non-magnetically conductive air, which would result in a lower magnetic flux density that interacts with the orthogonal end windings to generate output torque.

[0073] Please see Figure 6 As shown, it is a schematic diagram of the water jacket structure in an embodiment of the present invention;

[0074] Specifically, the water jacket 4 is disposed inside the radial stator core 22 and is respectively attached to the inner wall of the radial stator core 22 and the side wall of the axial stator core 23 for cooling the three-dimensional winding. The water jacket 4 includes a water jacket shell 41 embedded inside the radial stator core 22 and a water jacket rear cover 42 fitted with the water jacket shell 41. Several inlet and outlet water pipes 43 are disposed at the end of the water jacket rear cover 42. Several baffles 44 are disposed inside the water jacket shell 41 and are fixedly attached to the inner wall of the water jacket shell 41 by welding, dividing the longitudinal space of the water jacket shell 41 into several connected cooling intervals.

[0075] The water jacket 4 is a four-segment parallel water jacket, and the water jacket between two adjacent water inlet and outlet pipes 43 that are far apart forms a single circulating water channel, or multiple segments of parallel water jacket.

[0076] Please see Figure 7 As shown, it is a schematic diagram of the structure of the annular winding in an embodiment of the present invention;

[0077] Specifically, the three-dimensional winding adopts an L-shaped winding 21 and an annular winding 25. The straight section of the L-shaped winding is fitted with the radial stator core 22, and the bent section at the end extends out of the end face of the radial stator core 22 in an "L" shape. The annular winding 25 is ring-shaped and fitted with the radial stator core 22 and adheres to the inner wall of the water jacket 4 to form a closed magnetic circuit. The annular winding 25 can act as a heat-conducting element, directly transferring the winding temperature to the water jacket 4, thereby improving the heat dissipation capacity of the electromagnetic drive.

[0078] Please see Figure 8 As shown, it is a comparison diagram of the back electromotive force between the composite magnetic flux electromagnetic drive and the single magnetic flux electromagnetic drive in an embodiment of the present invention.

[0079] Specifically, as shown in the comparison results in the figure, the composite flux toroidal winding of the present invention has a higher back electromotive force amplitude and fundamental frequency amplitude compared to a single flux toroidal winding. Under the same armature current, this is beneficial for improving the output torque and power of the system. Furthermore, as... Figure 8 As shown in (a), although the two electromagnetic drives being compared have the same winding distribution, i.e., the same effect on the air gap magnetic flux density waveform, the back electromotive force waveform of the composite flux electromagnetic drive is closer to a sine wave. Figure 8 As shown in (b), the composite flux exhibits significantly fewer 3rd and 5th harmonics compared to radial single flux electromagnetic drive. The lower back electromotive force and higher harmonic content help reduce system torque ripple and improve the smoothness of system output. However, due to… Figure 8 In (b), it can also be observed that the 7th harmonic of the proposed composite flux is relatively large. Therefore, further reducing the air gap harmonic content will help to further reduce torque pulsation and stator core loss caused by higher harmonics.

[0080] Please see Figure 9 As shown, it is a torque comparison diagram between composite flux electromagnetic drive and single flux electromagnetic drive in an embodiment of the present invention.

[0081] Specifically, as shown in the comparison results in the figure, the average output torque of the composite magnetic flux of the present invention can be increased by 67.5 Nm, from 862.5 Nm to 930.0 Nm, an increase of approximately 7.8%. Since the two electromagnetic drives have the same system volume, their torque density can also be increased by 7.8%. Simultaneously, due to the increase in average torque, the torque ripple is reduced from 11.6% to 2.6%. Larger torque ripple in a single-flux electromagnetic drive can be reduced by adjusting the stator and rotor skew slots or the permanent magnet pole arc coefficient. However, this also leads to a reduction in winding coefficient or air gap magnetic load, resulting in a lower output torque for the traditional single-flux electromagnetic drive.

[0082] The rotor assembly 1 generates the composite magnetic flux upon rotation. When the composite magnetic flux sweeps across the three-dimensional windings of the stator assembly 2, a continuous rotational torque is formed on the rotor assembly 1. This rotational torque is transmitted to the rotating shaft 31 via the axial rotor support 111, driving the rotor assembly 1. The connecting assembly 3 supports the rotation of the rotor assembly 1 and transmits torque. The three-dimensional windings generate heat due to current losses. This heat is efficiently carried away by the circulating cooling water via the radial stator core 22 and the water jacket 4, maintaining the temperature rise of the three-dimensional windings below the rated value, thus ensuring efficient operation of the motor at a safe temperature.

[0083] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A water-cooled electromagnetic drive motor with a stacked, irregularly shaped slot composite flux three-dimensional winding, characterized in that, include: A rotor assembly for generating a composite magnetic flux includes an axial rotor for generating an axial magnetic flux and a radial rotor disposed at the outer end of the axial rotor for generating a radial magnetic flux. A stator assembly, disposed inside the rotor assembly and connected to the rotor assembly via a connecting assembly, includes a three-dimensional winding for interacting with the composite magnetic flux generated by the axial rotor and the radial rotor respectively, a radial stator core fitted with the three-dimensional winding, and an axial stator core disposed at one end of the radial stator core and fitted with the three-dimensional winding. A connecting assembly, which is connected to the rotor assembly and the stator assembly respectively, includes a rotating shaft disposed inside the rotor assembly and connected at one end to an axial rotor support, a pair of back-to-back angular contact ball bearings disposed at the inner end of the rotating shaft near the axial rotor support, and a deep groove ball bearing disposed at the end of the rotating shaft away from the axial rotor support. A water jacket assembly for cooling the three-dimensional winding includes a water jacket shell embedded inside the radial stator core and a water jacket back cover fitted with the water jacket shell. The radial stator core has a plurality of first irregularly shaped mounting slots arranged in a ring for mounting the three-dimensional winding, and the axial stator core has a plurality of second irregularly shaped mounting slots arranged in a ring for mounting the three-dimensional winding. The first irregularly shaped mounting slots and the second irregularly shaped mounting slots form an irregularly shaped slot configuration with the same slot area.

2. The stacked irregular slot composite flux three-dimensional winding water-cooled electromagnetic drive motor according to claim 1, characterized in that, The radial stator core is made of silicon steel sheets stacked axially, and the axial stator core is made of silicon steel strip wound radially. The radial stator core and the axial stator core are connected by the connecting assembly to form an annular heat dissipation space.

3. The stacked irregular slot composite flux three-dimensional winding water-cooled electromagnetic drive motor according to claim 1, characterized in that, The axial rotor includes an axial rotor support for providing support, an axial rotor magnetic back iron disposed inside the axial rotor support and connected to the axial rotor support, and an axial rotor magnetic pole array disposed on the side of the axial rotor magnetic back iron away from the rotor support. The axial rotor magnetic pole array is either a fan-shaped surface-mounted radially alternating magnetized magnetic pole array or a Halbach magnetic pole array without a rotor back iron.

4. The stacked irregular slot composite flux three-dimensional winding water-cooled electromagnetic drive motor according to claim 1, characterized in that, The radial rotor includes a radial rotor support for providing support, a radial rotor magnetic back iron disposed inside and connected to the radial rotor support, and a radial rotor magnetic pole array disposed inside and fitted inside the radial rotor magnetic back iron. The radial rotor magnetic pole array is either a fan-shaped surface-mounted radial alternating magnetized magnetic pole array or a Halbach magnetic pole array without a rotor back iron.

5. The stacked irregular slot composite flux three-dimensional winding water-cooled electromagnetic drive motor according to claim 4, characterized in that, The radial rotor magnetic pole array is an irregularly shaped magnetic pole array based on the injection of bottom arc fundamental wave and square wave, used to generate radial magnetic flux.

6. The stacked irregular slot composite flux three-dimensional winding water-cooled electromagnetic drive motor according to claim 1, characterized in that, The stator assembly also includes several types of cubic SMC material orthogonal teeth that are respectively connected to the radial stator core and the axial stator core and are arranged circumferentially around the orthogonal portion.

7. The stacked irregular slot composite flux three-dimensional winding water-cooled electromagnetic drive motor according to claim 1, characterized in that, The stator assembly further includes a stator core support embedded in the central hole of the water jacket housing to provide support for the radial stator core, a front bearing steel sleeve embedded inside the stator core support and in contact with the interior of the stator core support, a resolver mounting flange disposed at the end of the stator core support away from the front bearing steel sleeve, a rotary transformer mechanically connected to the resolver mounting flange for feedback of rotor position for electromagnetic drive, and an insulating end plate disposed at the radial stator core end away from the axial stator core and in contact with the radial stator core end.

8. The stacked irregular slot composite flux three-dimensional winding water-cooled electromagnetic drive motor according to claim 1, characterized in that, The axial cross-sectional shape of the first irregular mounting groove is trapezoidal, and the radial cross-sectional shape of the second irregular mounting groove is rectangular.

9. The water-cooled electromagnetic drive motor with stacked irregular slot composite flux three-dimensional winding according to claim 1, characterized in that, The water jacket assembly is a four-segment parallel water jacket or a multi-segment parallel water jacket.

10. The stacked irregular slot composite flux three-dimensional winding water-cooled electromagnetic drive motor according to claim 7, characterized in that, The angular contact ball bearing is embedded inside the front bearing sleeve, and the deep groove ball bearing is embedded inside the stator core support.

Images