A direct cooling system for stator winding end based on multi-section annular heat pipe array

Abstract

This invention provides a direct cooling system for the stator winding ends based on a multi-segment annular heat pipe array. The system includes a shaft, a rotor disposed outside the shaft, a stator core disposed around the rotor, and windings disposed within slots in the stator core. The windings form winding ends at the axial ends of the stator core. A water jacket is disposed outside the stator core, and a water channel for the flow of cooling medium is formed within the water jacket. Several heat pipes are disposed between the winding ends and the water jacket. Each heat pipe includes an evaporation section, a condensation section, and an insulating section connecting the evaporation and condensation sections. The evaporation section is arranged along the outer side of the winding ends and forms a direct heat transfer relationship with the winding ends. The condensation section is in close contact with the water jacket and located near its outer peripheral wall, exchanging heat with the cooling medium in the water channel through the water jacket. This invention achieves rapid heat removal and efficient heat dissipation from the winding ends, solving the problems of low cooling efficiency and long heat transfer paths.

Description

Technical Field

[0001] This invention relates to the field of motor thermal management and cooling structure design technology, specifically to a direct cooling system for the stator winding ends based on a multi-segment annular heat pipe array. Background Technology

[0002] With the development of new energy vehicles, aviation electric propulsion and high-end industrial equipment, motors are evolving towards higher power density, higher speed and higher integration. The significant increase in losses per unit volume has made the internal temperature rise of motors increasingly prominent, becoming a key factor restricting motor performance and reliability.

[0003] Among the various components of a motor, the stator winding is the main heat source, and its copper losses account for a large proportion of the total losses. In particular, the end area of ​​the stator winding is particularly problematic. On the one hand, due to the dense winding arrangement and complex overlapping of the wires, heat is difficult to dissipate evenly. On the other hand, it is far from the effective heat transfer path of the stator core, and its heat dissipation conditions are significantly worse than those of the winding in the slots, making it very easy for local high temperatures or even heat accumulation to occur.

[0004] Existing motor cooling technologies mainly focus on the following forms:

[0005] (1) External air cooling: It relies on air convection to remove heat, has a low heat transfer coefficient, and is difficult to meet the requirements of high power density motors;

[0006] (2) Water jacket cooling: By setting a water jacket on the outside of the stator core, heat is conducted to the cooling medium through the core. However, the winding ends need to transfer heat through multiple paths such as winding-slot insulation-core, resulting in a large thermal resistance.

[0007] (3) Oil cooling or spray cooling: The structure is complex, the requirements for sealing and reliability are high, and there are potential safety hazards in insulation.

[0008] In the above scheme, the winding ends still mainly rely on indirect cooling methods and fail to be specifically optimized for the high heat flux density characteristics of the end area, making the winding ends a weak link in the motor thermal design.

[0009] Therefore, how to construct a direct cooling system for the stator winding ends based on a multi-segment annular heat pipe array that can directly act on the winding ends within a limited space, with low thermal resistance, high cooling efficiency, and strong engineering feasibility, is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0010] The purpose of this invention is to propose a direct cooling system for the stator winding end based on a multi-segment annular heat pipe array. By directly arranging the heat pipe evaporation section on the outside of the winding end and combining it with a water jacket cooling structure, the system can achieve rapid heat dissipation and efficient heat transfer from the winding end, thereby solving the problems of low cooling efficiency and long heat transfer path.

[0011] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The present invention provides a direct cooling system for the stator winding end based on a multi-segment annular heat pipe array. This direct cooling system for the stator winding end includes: a rotating shaft, a rotor disposed on the outside of the rotating shaft, a stator core disposed on the outer periphery of the rotor, and a winding disposed within a slot in the stator core. The winding forms a winding end at the axial end of the stator core. A water jacket is provided on the outside of the stator core, and a water channel for the flow of cooling medium is provided within the water jacket. A plurality of heat pipes are disposed between the winding end and the water jacket. Each heat pipe includes an evaporation section, a condensation section, and an insulating section connecting the evaporation section and the condensation section.

[0012] The evaporation section is arranged along the outer side of the winding end and forms a direct heat transfer relationship with the winding end, which is used to directly absorb the heat generated during the operation of the winding end; the condensation section is close to the water jacket and located on the side of the water jacket near its outer peripheral wall, and exchanges heat with the cooling medium in the water channel through the water jacket, thereby realizing the direct cooling of the winding end.

[0013] As a further improvement, the heat pipe is a multi-segment annular heat pipe with an overall curved structure to adapt to the spatial distribution characteristics of the winding ends.

[0014] As a further improvement, the heat pipe has an overall ring structure, with the evaporation section and the condensation section located on opposite sides of the ring structure, and the insulation section located in the ring bend area.

[0015] As a further improvement, the heat pipes are arranged in an array along the circumferential direction of the winding ends.

[0016] As a further improvement, the evaporation section is fitted along the outer contour of the winding end.

[0017] As a further improvement, the condensation section is located outside the water jacket and forms a heat exchange relationship with the water channel.

[0018] As a further improvement, fins are provided on the outer side of the condensation section to increase the heat exchange area with the cooling medium or the external environment.

[0019] As a further improvement, the fins are arranged at intervals along the length of the condensation section.

[0020] As a further improvement, the heat pipe is fixed to the water jacket by a heat pipe mounting bracket.

[0021] As a further improvement, the heat pipe mounting bracket is fixed by means of snap-fit, crimping, screwing, or embedding.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] (1) The heat transfer path is significantly shortened. The heat generated at the end of the winding does not need to be conducted through the iron core, but directly enters the heat pipe evaporation section, which greatly reduces the overall thermal resistance.

[0024] (2) Improve the heat dissipation capacity of the winding end, utilize the phase change heat transfer characteristics of the heat pipe to achieve efficient heat transfer and effectively suppress local hot spots at the winding end.

[0025] (3) The structure is highly adaptable. The annular heat pipe can be bent according to the spatial shape of the winding end, and the arrangement is flexible and does not affect the original electromagnetic structure of the motor.

[0026] (4) The system has good compatibility and can work in conjunction with the existing water jacket cooling system without requiring major modifications to the cooling medium circuit.

[0027] (5) It has high engineering feasibility, clear structure, and simple installation method, making it suitable for modification or integrated application on existing motor platforms. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the axial cross-sectional structure of the winding ends and heat pipe arrangement of the motor of the present invention.

[0029] Figure 2 This is a schematic diagram of the radial cross-section of the motor of the present invention;

[0030] Figure 3 This is an exploded view of the overall structure of the motor of the present invention;

[0031] Figure 4 This is a partially enlarged schematic diagram of the contact structure between the heat pipe evaporator section and the winding end;

[0032] In the figure: 1-shaft; 2-rotor; 3-winding; 5-stator core; 6-water jacket; 7-condensation section; 8-fins; 9-water channel; 10-insulation section; 11-evaporation section; 12-heat pipe mounting base; 31-winding end. Detailed Implementation

[0033] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0034] like Figures 1 to 3As shown, the stator winding end direct cooling system based on a multi-segment annular heat pipe array of the present invention is used in a motor. The motor includes a shaft 1, a rotor 2, a stator core 5, and windings 3 disposed in the stator core slots. The windings 3 form winding ends 31 at both axial ends of the stator core. Slot insulation is provided between the windings 3 and the stator core 5 for electrical isolation. A water jacket 6 is coaxially disposed outside the stator core 5, forming a closed or semi-closed water channel 9 structure within the water jacket 6. The cooling medium can circulate in the water channel to remove the heat generated during motor operation. Several annular heat pipes are arranged between the winding ends 31 and the water jacket 6. The heat pipes are preferably multi-segment annular structures, with one end forming an evaporation section 11, the other end forming a condensation section 7, and the middle portion forming an insulation section 10. The heat pipe evaporation section 11 is arranged along the outer surface of the winding ends 31 and forms close contact with the winding ends 31 to achieve efficient heat absorption.

[0035] like Figure 4 As shown, the heat pipe evaporation section can be arranged continuously or in segments along the circumference of the winding end, and its contact form can be surface contact or line contact to balance heat dissipation efficiency and installation feasibility. Multiple heat pipes are spaced apart along the circumference of the winding end to form a heat pipe array, so that the heat at the winding end can be uniformly extracted. The heat pipe condensation section is arranged close to the water jacket and exchanges heat with the cooling medium in the water circuit through the water jacket. In some embodiments, fins 8 can be provided on the outside of the condensation section to further increase the heat exchange area and improve the condensation efficiency. To ensure structural stability, the heat pipe is fixed to the water jacket or the housing by the fixing structure 12 to maintain a reliable positional relationship during motor operation. When the motor is running, the heat generated at the winding end 31 is first absorbed by the heat pipe evaporation section and transferred to the condensation section 7 through the heat pipe's internal heat transfer mechanism. Finally, it is carried away by the cooling medium in the water jacket 6, thereby achieving continuous and efficient cooling of the winding end 31.

[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any modifications or equivalent changes made based on the technical essence of the present invention shall still fall within the scope of protection claimed by the present invention.

Claims

1. A multi-section loop heat pipe array based direct cooling system for stator winding end portions, characterized in that, The stator winding end direct cooling system based on a multi-segment annular heat pipe array includes: a rotating shaft (1), a rotor (2) disposed outside the rotating shaft (1), a stator core (5) disposed on the outer periphery of the rotor (2), and a winding (3) disposed in the slot of the stator core (5). The winding (3) forms a winding end (31) at the axial end of the stator core (5). A water jacket (6) is provided outside the stator core (5), and a water channel (9) for the flow of cooling medium is provided inside the water jacket (6). A plurality of heat pipes are disposed between the winding end (31) and the water jacket (6). The heat pipes include an evaporation section (11), a condensation section (7), and an adiabatic section (10) connecting the evaporation section (11) and the condensation section (7). The evaporation section (11) is arranged along the outer side of the winding end (31) and forms a direct heat transfer relationship with the winding end (31); the condensation section (7) is close to the water jacket (6) and is located on the side of the water jacket (6) near its outer peripheral wall, and exchanges heat with the cooling medium in the water channel (9) through the water jacket (6).

2. The multi-section loop heat pipe array based direct cooling system for stator winding end portions according to claim 1, characterized in that, The heat pipe is a multi-segment annular heat pipe with an overall curved structure to adapt to the spatial distribution characteristics of the winding end (31).

3. The multi-section loop heat pipe array based direct cooling system for stator winding end portions as claimed in claim 1 wherein, The heat pipe has an overall ring structure, with the evaporation section (11) and the condensation section (7) located on both sides of the ring structure, and the insulation section (10) located in the ring bend area.

4. A multi-section loop heat pipe array based direct cooling system for stator winding end portions according to claim 2 or 3, characterized in that, The heat pipes are arranged in an array along the circumference of the winding end (31).

5. A direct cooling system for stator winding ends based on a multi-segment annular heat pipe array according to claim 1, characterized in that, The evaporation section (11) is fitted along the outer contour of the winding end (31).

6. The stator winding end direct cooling system based on a multi-segment annular heat pipe array according to claim 1, characterized in that, Fins (8) are provided on the outside of the condensation section (7) to increase the heat exchange area with the cooling medium or the external environment.

7. A direct cooling system for stator winding ends based on a multi-segment annular heat pipe array according to claim 4, characterized in that, The fins (8) are arranged at intervals along the length of the condensation section (7).

8. A direct cooling system for stator winding ends based on a multi-segment annular heat pipe array according to claim 4, characterized in that, The heat pipe is fixed to the water jacket (6) by a heat pipe mounting bracket (12).

9. A direct cooling system for stator winding ends based on a multi-segment annular heat pipe array according to claim 4, characterized in that, The heat pipe mounting base (12) is fixed by means of snap-fit, crimping, screwing or embedding.

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