Double-rotor axial magnetic flux low-voltage energy-saving motor device

Abstract

The invention relates to the technical field of double-rotor magnetic flux motors, in particular to a double-rotor axial magnetic flux low-voltage energy-saving motor device, which comprises a shell in which a motor mounting cavity is formed; the stator assembly is arranged in the motor mounting cavity, the stator assembly comprises a stator iron core and a multi-phase concentrated winding, and the multi-phase concentrated winding is wound on the stator iron core and is wound by a rectangular copper flat wire; the double-rotor assembly comprises a first permanent magnet rotor, a second permanent magnet rotor and an output shaft, and the first permanent magnet rotor and the second permanent magnet rotor are coaxially arranged on the two sides of the stator assembly respectively and are coaxially and fixedly connected through the output shaft; and the cooling assembly comprises a plurality of cooling plates, and the cooling plates are respectively embedded on the stator iron core and form a plurality of cooling subareas. According to the invention, 2-4 low-turn design is matched with the large-section rectangular copper flat wire, and the flat wire branches are symmetrically connected in parallel in the circumferential direction, so that the high-frequency alternating current loss is effectively inhibited, the copper loss is reduced, the flat wire is matched with the cooling plate to avoid local overheating, and the energy-saving effect is improved.

Description

Technical Field

[0001] This invention relates to the field of dual-rotor flux motor technology, and particularly to a dual-rotor axial flux low-voltage energy-saving motor device. Background Technology

[0002] With the advancement of the national "dual-carbon" strategy, an increasing number of mobile or stationary industrial devices are adopting 48V, 72V, or 96V DC low-voltage power supply systems. These low-voltage systems offer advantages such as high electrical safety, low cable costs, and good compatibility with lithium battery platforms, making them particularly suitable for operating environments with stringent explosion-proof requirements.

[0003] However, in the existing technology, low-voltage power supply also poses a severe challenge to the drive motor. In order to output the same power, the current needs to be significantly increased. Under this condition, traditional radial flux induction motors have problems such as a sharp increase in copper loss, excessive temperature rise, and a sharp drop in efficiency. In order to meet the requirements of continuous high load operation, more energy needs to be supplied to the cooling system, which makes it difficult to meet the energy-saving requirements.

[0004] Therefore, there is an urgent need for a dual-rotor axial flux motor device that can adapt to uneven local thermal loads under low voltage and high current conditions and has energy-saving capabilities. Summary of the Invention

[0005] The main objective of this invention is to provide a dual-rotor axial flux low-voltage energy-saving motor device, which aims to solve the problem that existing dual-rotor axial flux motor devices cannot adapt to uneven local heat load and energy-saving requirements under low voltage and high current conditions.

[0006] To achieve the above objectives, the present invention proposes a dual-rotor axial flux low-voltage energy-saving motor device, comprising:

[0007] A housing, wherein a motor mounting cavity is formed inside the housing;

[0008] The stator assembly is fixedly disposed at the axial center position of the motor mounting cavity. The stator assembly includes a stator core and a multi-phase concentrated winding. The multi-phase concentrated winding is wound on the stator core and is wound with rectangular copper flat wire. The number of turns of each phase winding is 2 to 4 turns.

[0009] A dual-rotor assembly, comprising a first permanent magnet rotor, a second permanent magnet rotor, and an output shaft, wherein the first permanent magnet rotor and the second permanent magnet rotor are coaxially disposed on both sides of the stator assembly and are coaxially fixedly connected through the output shaft;

[0010] The cooling assembly includes multiple cooling plates, which are respectively embedded on the stator core and form multiple cooling zones. Each cooling zone consists of 2 to 4 adjacent stator pole units. Each cooling plate is provided with a cooling channel, and the cooling channels of each cooling plate are connected in parallel.

[0011] Furthermore, the cross-sectional dimensions of the rectangular copper flat wire are 6mm~10mm in width and 1.5mm~3mm in thickness, and the multi-phase concentrated winding is a 9-phase winding, with each phase winding spaced apart from the others.

[0012] Furthermore, the stator core is composed of 12 to 24 sector-shaped magnetic pole units, and each sector-shaped magnetic pole unit corresponds to a stator tooth.

[0013] Furthermore, the multiphase concentrated winding adopts a multi-branch parallel structure, with each phase winding consisting of 2 to 4 independent flat wire branches connected in parallel, and the multiple branches are symmetrically distributed in the circumferential direction of the stator core.

[0014] Furthermore, the permanent magnets on both the first and second permanent magnet rotors are arranged in a Halbach array.

[0015] Furthermore, the cooling assembly also includes a branch valve, which is connected to each of the cooling channels.

[0016] Furthermore, the output shaft has a hollow structure, and a temperature measuring cavity is provided inside the output shaft. A distributed temperature sensor is fixedly installed in the temperature measuring cavity near the multiphase concentrated winding.

[0017] This invention significantly reduces the DC resistance of the winding by using a low-turn design of 2-4 turns combined with large-section rectangular copper flat wire. The flat wire branches of each phase winding are symmetrically connected in parallel in the circumferential direction, which effectively suppresses high-frequency AC loss and reduces copper loss. At the same time, the cooling assembly divides the stator core into multiple cooling zones to ensure uniform distribution of coolant, achieve precise zoned cooling of winding heat, avoid local overheating, and improve energy saving effect. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of the dual-rotor axial flux low-voltage energy-saving motor device of the present invention;

[0020] Figure 2 This is a schematic diagram of the stator assembly of the present invention;

[0021] Figure 3 This is a schematic diagram of the cooling plate of the present invention;

[0022] Figure 4 This is a schematic diagram of the output shaft of the present invention;

[0023] Figure 5 This is a partial magnetic circuit diagram of the present invention.

[0024] Explanation of icon numbers:

[0025] label name label name 1000 Dual-rotor axial flux low-voltage energy-saving motor device 100 housing assembly 110 Motor mounting cavity 200 stator assembly 210 stator core 220 Multiphase concentrated winding 300 Dual rotor assembly 310 First permanent magnet rotor 320 Second permanent magnet rotor 330 Output shaft 331 Temperature measuring cavity 332 Temperature sensor 400 Cooling components 410 Cooling plate 420 Diverter valve

[0026] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0028] It should be noted that all directional indications in the embodiments of the present invention are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0029] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0030] Understandably, in industrial low-voltage (380V) power distribution environments, according to the power formula, pursuing high power output under low voltage will inevitably lead to extremely high current. High current will result in high copper loss. The resistance loss of the winding is proportional to the square of the current, which seriously affects efficiency. At the same time, high loss will lead to high temperature rise. Heat concentration will reduce efficiency, damage insulation, threaten permanent magnets, and ultimately make the motor unable to operate stably.

[0031] However, existing dual-rotor structures confine the heat generated by the stator and its windings to the middle of the motor, resulting in regional overheating. Traditional casing water cooling or a single internal cooling path cannot provide differentiated and efficient heat dissipation to different heat source areas inside the stator, especially the winding ends where resistance losses are most concentrated and the straight sections embedded in the iron core. This leads to a significant temperature gradient inside the motor. Localized overheating hotspots not only threaten the safety of insulation materials and permanent magnets, but also create a vicious cycle of "temperature rise - increased resistance - increased losses - even higher temperature rise" as winding resistance increases with temperature. Ultimately, this causes the motor's efficiency to drop sharply near its rated point, making true continuous energy-saving operation impossible.

[0032] Therefore, as Figures 1-5 As shown, the present invention proposes a dual-rotor axial flux low-voltage energy-saving motor device 1000, comprising:

[0033] The system comprises: a housing 100, with a motor mounting cavity 110 formed inside; a stator assembly 200, fixedly disposed at the axial center of the motor mounting cavity 110, the stator assembly 200 including a stator core 210 and a multi-phase concentrated winding 220 wound on the stator core 210, the multi-phase concentrated winding 220 being wound with rectangular copper flat wire, each phase winding having 2-4 turns; and a dual rotor assembly 300, including a first permanent magnet rotor 310 and a second permanent magnet rotor 300. The magnetic rotor 320 and the output shaft 330, the first permanent magnet rotor 310 and the second permanent magnet rotor 320 are respectively coaxially arranged on both sides of the stator assembly 200 and are coaxially fixedly connected through the output shaft 330; the cooling assembly 400 includes multiple cooling plates 410, which are respectively embedded on the stator core 210 and form multiple cooling zones. Each cooling zone is composed of 2 to 4 adjacent stator magnetic pole units. Each cooling plate 410 is provided with a cooling channel, and the cooling channels of each cooling plate are connected in parallel.

[0034] In one embodiment, the stator assembly 200 is bolted to an axially centered mounting flange inside the housing 100 to ensure that its position is centered and there is no axial offset. The stator assembly 200 includes a stator core 210 made of soft magnetic composite material (SMC). A multi-phase concentrated winding 220 is wound on the stator core 210. The winding uses rectangular cross-section copper flat wire. The operator winds 2 to 4 turns on each tooth of the stator core 210 using a winding tool to form a concentrated coil. Multiple cooling plates 410 in the cooling assembly 400 are embedded on one side of the stator core 210 during manufacturing. Each cooling plate 410 corresponds to a cooling zone, and each zone covers 2 to 4 adjacent stator pole units. The cooling channels of the cooling plates 410 are connected in parallel through a manifold located on the side wall of the housing 100. The housing 100 is also provided with an inlet and an outlet. Coolant flows in from the inlet, passes through the cooling channels of each cooling zone, and then flows out from the outlet, achieving uniform cooling of the stator windings. This invention is suitable for low-voltage, high-current operating environments.

[0035] In another embodiment, the cooling assembly 400 further includes a variable flow cooling pump and a variable frequency drive module. The variable flow cooling pump dynamically adjusts the coolant flow rate of each cooling zone according to the temperature feedback signal of each cooling zone. The variable frequency drive module is connected to the variable flow cooling pump. The power switching devices of the variable frequency drive module can be silicon carbide or gallium nitride devices. It is also electrically connected to the multiphase concentrated winding 220 via a control bus to control the power of the variable flow cooling pump and the multiphase concentrated winding 220. Thermally conductive insulating pads are provided between each pole unit of the stator core 210. The thermal conductivity of the thermally conductive insulating pads is not less than 1.5 W / (m*K), which is used to improve heat conduction efficiency while providing electrical isolation.

[0036] In this invention, the cross-sectional dimensions of the rectangular copper flat wire are 6mm~10mm in width and 1.5mm~3mm in thickness. The multiphase concentrated winding 220 is a 9-phase winding, with each phase winding spaced apart from the others.

[0037] In one embodiment, the windings made of rectangular copper flat wires can increase the slot fill factor, fill more conductive material in the same space, thereby reducing DC resistance, reducing losses, and improving energy-saving effect.

[0038] In another embodiment, the two leads of each phase winding are connected to waterproof terminals on the side wall of the housing 100 by welding. This 9-phase structure significantly reduces current harmonics and provides the hardware foundation for subsequent parallel control of multiple drivers. Operators must ensure that the phase leads do not cross or share terminals during wiring to guarantee the electrical independence of each phase.

[0039] In this invention, the stator core 210 is composed of 12 to 24 sector-shaped magnetic pole units, and each sector-shaped magnetic pole unit corresponds to a stator tooth.

[0040] In one embodiment, the stator core 210 is composed of 18 independent sector-shaped magnetic pole units. Each sector-shaped unit is made of soft magnetic composite material powder through warm pressing and surface phosphating, exhibiting high magnetic permeability and low eddy current loss characteristics. Each sector-shaped magnetic pole unit corresponds to one stator tooth. During assembly, the operator places the 18 sector-shaped units sequentially into the stator support, ensuring circumferential alignment using positioning pins, and then tightens them with non-magnetic stainless steel clamps to form a complete annular stator core 210. This yokeless segmented structure not only facilitates the embedding of the cooling plate 410 but also significantly reduces high-frequency iron losses. A mounting slot for the cooling plate 410 is pre-drilled on the back of each magnetic pole unit, facilitating the subsequent integration of the cooling assembly 400.

[0041] In this invention, the multiphase concentrated winding 220 adopts a multi-branch parallel structure, and each phase winding is composed of 2 to 4 independent flat wire branches connected in parallel. The multiple branches are symmetrically distributed in the circumferential direction of the stator core 210.

[0042] In one embodiment, the multiphase concentrated winding 220 is composed of multiple identical rectangular copper flat wire branches connected in parallel, forming multiple electrically parallel but physically separated branches, which are symmetrically distributed along the circumference of the stator core 210. This multi-branch parallel structure effectively reduces the current density of a single conductor and reduces AC losses caused by the skin effect and proximity effect. Simultaneously, since the path lengths of each branch are basically the same, the current distribution is uniform, avoiding localized overheating. When soldering the leads, the operator must solder the ends of multiple branches together to the same phase terminal to ensure low contact resistance.

[0043] In this invention, the permanent magnets on the first permanent magnet rotor 310 and the second permanent magnet rotor 320 are arranged in a Halbach array.

[0044] Understandably, the Halbach array is arranged such that each pole consists of four permanent magnets, with their magnetization directions being radially outward, tangentially clockwise, radially inward, and tangentially counterclockwise, thereby concentrating the magnetic field on the air gap side and significantly weakening the magnetic field on the back iron side.

[0045] In one embodiment, both the first permanent magnet rotor 310 and the second permanent magnet rotor 320 are arranged in a Halbach array. During assembly, the operator sequentially attaches neodymium iron boron permanent magnet blocks to the rotor back iron according to a pre-designed magnetization direction. This structure increases the air gap magnetic flux density by approximately 15% while reducing rotor iron losses. The Halbach arrays of the two rotors are arranged in a mirror-symmetric manner to ensure symmetrical dual-air gap magnetic circuits, reduce axial magnetic pull, and guarantee uniform magnetic field distribution.

[0046] In this invention, the cooling assembly 400 further includes a branch valve 420, which is connected to each cooling channel.

[0047] In one embodiment, the branch valve 420 is an electrically controlled branch valve 420. This branch valve 420 is installed outside the housing 100 and at the end furthest from the output shaft. The branch valve is connected to a cooling pump (not shown in the figure), and its outlet is connected to the inlet of each cooling zone via pipelines. The branch valve 420 contains multiple proportional regulating valve cores driven by a motor. During motor operation, the control system collects the temperature signals of each cooling zone in real time. When the temperature of a zone exceeds a set threshold (e.g., 85°C), the control unit sends a command to the branch valve 420 to increase the opening of the corresponding valve core, thereby increasing the coolant flow rate; conversely, it reduces the flow rate. Before starting the equipment, the operator must check the wiring of the branch valve 420 for correctness and set the temperature threshold and flow rate adjustment curve through the HMI interface. This dynamic flow distribution mechanism enables on-demand cooling, improves cooling efficiency, and reduces pump power consumption.

[0048] In this invention, the output shaft 330 has a hollow structure, and a temperature measuring cavity 331 is provided inside the output shaft 330. A distributed temperature sensor 332 is fixedly installed in the temperature measuring cavity 331 near the multiphase concentrated winding 220.

[0049] In one embodiment, the output shaft 330 adopts a hollow tubular structure. During assembly, the operator inserts a distributed fiber optic temperature sensor 332 through one end of the output shaft 330, arranges it axially, and fixes it to the inner wall near the end of the stator winding with epoxy resin. This fiber optic sensor, based on the principle of a Bragg grating (FBG), can continuously measure the temperature at multiple points along the axial direction. The sensor's tail end extends to a fiber optic connector outside the housing 100, connecting to the temperature monitoring module. During motor operation, the monitoring module collects real-time winding hotspot temperature data and uploads it to the main controller. If the temperature exceeds a safety limit (e.g., 130°C), the system will automatically reduce power or shut down. The operator can read the temperature distribution curve via a handheld terminal for preventative maintenance.

[0050] This invention significantly reduces the DC resistance of the windings by employing a low-turns design of 2-4 turns combined with large-section rectangular copper flat wire. Each phase winding uses 2-4 flat wire branches symmetrically connected in parallel circumferentially, effectively suppressing high-frequency AC losses and reducing copper losses. Simultaneously, the cooling assembly divides the stator core into multiple cooling zones, each equipped with an independent cooling plate, and the cooling channels are arranged in parallel to ensure uniform coolant distribution. Combined with the dynamic flow regulation function of the branch valve, cooling resources can be allocated as needed based on the real-time temperature of each zone, achieving precise zoned cooling of the winding heat and preventing localized overheating.

[0051] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made under the concept of the present invention using the contents of the present invention specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A dual-rotor axial flux low-voltage energy-saving motor device, characterized in that, include: A housing, wherein a motor mounting cavity is formed inside the housing; The stator assembly is fixedly disposed at the axial center position of the motor mounting cavity. The stator assembly includes a stator core and a multi-phase concentrated winding. The multi-phase concentrated winding is wound on the stator core and is wound with rectangular copper flat wire. The number of turns of each phase winding is 2 to 4 turns. A dual-rotor assembly, comprising a first permanent magnet rotor, a second permanent magnet rotor, and an output shaft, wherein the first permanent magnet rotor and the second permanent magnet rotor are coaxially disposed on both sides of the stator assembly and are coaxially fixedly connected through the output shaft; The cooling assembly includes multiple cooling plates, which are respectively embedded on the stator core and form multiple cooling zones. Each cooling zone consists of 2 to 4 adjacent stator pole units. Each cooling plate is provided with a cooling channel, and the cooling channels of each cooling plate are connected in parallel.

2. The dual-rotor axial flux low-voltage energy-saving motor device as described in claim 1, characterized in that, The rectangular copper flat wire has a cross-sectional dimension of 6mm~10mm in width and 1.5mm~3mm in thickness. The multiphase concentrated winding is a 9-phase winding, with each phase winding spaced apart from the others.

3. The dual-rotor axial flux low-voltage energy-saving motor device as described in claim 2, characterized in that, The stator core is composed of 12 to 24 sector-shaped magnetic pole units, and each sector-shaped magnetic pole unit corresponds to a stator tooth.

4. The dual-rotor axial flux low-voltage energy-saving motor device as described in claim 3, characterized in that, The multiphase concentrated winding adopts a multi-branch parallel structure, with each phase winding consisting of 2 to 4 independent flat wire branches connected in parallel. The multiple branches are symmetrically distributed in the circumferential direction of the stator core.

5. The dual-rotor axial flux low-voltage energy-saving motor device as described in claim 1, characterized in that, The permanent magnets on both the first and second permanent magnet rotors are arranged in a Halbach array.

6. The dual-rotor axial flux low-voltage energy-saving motor device as described in claim 1, characterized in that, The cooling assembly also includes branch valves that are connected to each of the cooling channels.

7. The dual-rotor axial flux low-voltage energy-saving motor device as described in any one of claims 1 to 6, characterized in that, The output shaft has a hollow structure, and a temperature measuring cavity is provided inside the output shaft. A distributed temperature sensor is fixedly installed in the temperature measuring cavity near the multiphase concentrated winding.

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