Phase change heat dissipation motor stator

Abstract

The application relates to the field of motor stators, in particular to a phase-change heat dissipation motor stator, which is suitable for a micro high-speed motor with high heat dissipation performance requirements. The motor stator comprises a ring-shaped stator core, an insulation framework sleeved on the stator core, a winding arranged on the insulation framework and a phase-change heat dissipation assembly sleeved on the periphery of the winding; the stator core is formed by laminating silicon steel sheets, a plurality of radial tooth portions are uniformly extended on the inner circumference of the stator core, and a wire slot is formed between adjacent tooth portions; the insulation framework is made of insulation material and covers the tooth portions and the end face of the stator core, so as to realize the electrical insulation between the winding and the stator core. The application realizes three-dimensional heat coupling through a structure-matched closed phase-change heat dissipation assembly and the winding, establishes an efficient heat management path, actively controls temperature by using the phase-change latent heat principle, and simultaneously has good heat absorption and heat dissipation performance, and avoids the problem of setting a complex fluid circuit in a micro space.

Description

Technical Field

[0001] This application relates to the field of motor stators, and in particular to a phase-change heat dissipation motor stator, which is suitable for miniature high-speed motors with high heat dissipation performance requirements. Background Technology

[0002] In the field of motor technology, stator windings generate a significant amount of Joule heat during operation due to resistance and alternating magnetic fields. Heat dissipation capacity is crucial to motor performance and reliability. Miniature high-speed motors face extremely challenging operating modes in applications such as high-speed fans (devices driven at extremely high speeds to generate strong airflow for industrial purging or special ventilation). These applications typically require the motor to rapidly accelerate to high speeds within a short period to output powerful instantaneous airflow, followed by a rapid stop or slowdown, exhibiting periodic, intermittent high-load operation. During these cycles, the motor windings endure tremendous thermal shocks in a very short time, generating and accumulating high-density heat. If this peak heat cannot be quickly and effectively absorbed and dissipated, the winding temperature will rise sharply within several operating cycles. This rapid temperature fluctuation and peak high temperature not only instantly reduce motor efficiency due to increased winding resistance but also cause continuous fatigue stress on the insulation material, accelerating its aging process and severely limiting the motor's lifespan and operational reliability.

[0003] To address motor heat dissipation, existing technologies primarily employ natural air cooling, forced air cooling, and liquid cooling. Taking a high-speed fan as an example, while the motor is accompanied by a strong airflow, heat dissipation remains a problem inside the motor, particularly in the stator windings. Forced air cooling is a common solution, but due to the space constraints of miniaturized motors, the internal airflow channels are narrow, airflow resistance is high, and the improvement in heat dissipation efficiency is limited. More importantly, air, as a cooling medium, inherently has low specific heat capacity and low thermal conductivity, limiting its instantaneous heat absorption capacity and making it difficult to handle the concentrated high heat flux generated by high loads. While liquid cooling technology offers excellent heat dissipation performance under steady-state conditions, its system response has inertia, making it difficult to smooth out instantaneous heat peaks. Furthermore, integrating a complex and reliable closed-loop microfluidic system within the limited space of a micro motor presents significant technological challenges and cost pressures. Therefore, existing heat dissipation technologies are insufficient to meet the urgent needs of micro high-speed motors in applications such as high-speed fans for rapid response and high heat flux density handling capabilities under short-term, intermittent high-load conditions requiring a thermal management system. Utility Model Content

[0004] The purpose of this application is to overcome at least one deficiency in the existing technology and provide a phase-change heat dissipation motor stator, which achieves efficient control of the winding operating temperature through a three-dimensionally thermally coupled sealed shell and its internal phase-change material. This structure is particularly suitable for solving the heat dissipation problem faced by micro high-speed motors due to their extremely compact space and high heat flux density.

[0005] To achieve the above objectives, this application discloses a phase change heat dissipation motor stator, which includes an annular stator core, an insulating frame fitted on the stator core, windings wound on the insulating frame, and a phase change heat dissipation assembly fitted around the windings.

[0006] The stator core is made of stacked silicon steel sheets, with multiple radial teeth extending evenly along its inner circumference, forming grooves between adjacent teeth.

[0007] The insulating frame is made of insulating material and covers the teeth and end faces of the stator core to achieve electrical insulation between the winding and the stator core.

[0008] The winding is made of conductive material wound on an insulating frame and sleeved on the teeth, with adjacent windings forming a mating gap in the slot.

[0009] The phase change heat dissipation component is constructed as a closed hollow shell structure. This structure includes an upper ring, a lower ring, and multiple connecting posts connecting the upper and lower rings; the internal cavities of the upper ring, lower ring, and connecting posts are interconnected, collectively forming a sealed phase change material accommodating cavity.

[0010] The number and position of the connecting posts correspond to the mating gap position, so that the phase change heat dissipation component can be sleeved on the stator core with the windings already wound from top to bottom.

[0011] In the assembled state, the connecting post of the phase change heat dissipation component is embedded in the mating gap and adapted to the side profile of the winding. To optimize the heat conduction path, thermally conductive silicone pads or thermally conductive paste are filled between the side of the connecting post and the side of the winding, as well as between the lower surface of the upper ring and the upper surface of the lower ring and the winding end, to ensure a tight physical contact between the phase change heat dissipation component and the winding component, minimizing contact thermal resistance.

[0012] The phase change material accommodating cavity is filled with phase change material, which undergoes a phase change under the heat generated by the motor operation, thereby efficiently absorbing and storing the heat generated by the winding.

[0013] As a preferred embodiment, the phase change material is paraffin wax.

[0014] In summary, this application establishes a highly efficient thermal management path by achieving three-dimensional thermal coupling between a structurally matched sealed phase change heat dissipation component and the winding. It actively controls the temperature by utilizing the latent heat of phase change, achieving good heat absorption and dissipation while avoiding the problem of setting up complex fluid circuits in a micro-space.

[0015] The beneficial effects listed above are not exhaustive of all advantages. Other potential beneficial effects and detailed technical implementation methods will be further disclosed in the embodiments or other descriptive sections of this application. Attached Figure Description

[0016] A better understanding of various aspects of this disclosure will be achieved by reading the following detailed description in conjunction with the accompanying drawings. The positions, dimensions, and extents of the structures shown in the drawings, etc., do not always represent actual positions, dimensions, and extents. In the drawings:

[0017] Figure 1 This is a schematic diagram of the structure of one embodiment disclosed in this application.

[0018] Figure 2 This is a schematic diagram of the structure after removing the phase change heat dissipation component in one embodiment of this application.

[0019] Figure 3 This is a schematic diagram of the structure of one embodiment disclosed in this application from another perspective.

[0020] Figure 4 This is a schematic diagram of the stator core structure in one embodiment of this application.

[0021] Figure 5 This is a schematic diagram of the structure of the insulating skeleton in one embodiment of this application.

[0022] Figure 6 This is a schematic diagram of the phase change heat dissipation component structure in one embodiment of this application. Detailed Implementation

[0023] The present disclosure will now be described with reference to the accompanying drawings, which illustrate several embodiments of the present disclosure. However, it should be understood that the present disclosure can be presented in many different ways and is not limited to the embodiments described below; in fact, the embodiments described below are intended to make the disclosure more complete and to fully illustrate the scope of protection of the present disclosure to those skilled in the art. It should also be understood that the embodiments disclosed herein can be combined in various ways to provide further additional embodiments.

[0024] It should be understood that the same reference numerals denote the same elements in all the accompanying drawings. For clarity, the dimensions of certain features may be modified in the drawings.

[0025] It should be understood that the terminology used in this specification is for describing specific embodiments only and is not intended to limit this disclosure. All terms used in this specification (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. For the sake of brevity and / or clarity, techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail; however, where appropriate, such techniques, methods, and apparatus should be considered part of this specification.

[0026] Unless otherwise specified, the singular forms “a,” “the,” and “the” used in this specification include the plural forms. The terms “comprising,” “including,” and “containing” used in this specification indicate the presence of the claimed feature but do not exclude the presence of one or more other features. The term “and / or” used in this specification includes any and all combinations of one or more of the relevant listed items.

[0027] See attached document Figures 1 to 6 The exemplary structure shown in this embodiment includes an annular stator core 1, an insulating frame 2 fitted on the stator core 1, a winding 3 wound on the insulating frame 2, and a phase change heat dissipation component 4 fitted around the winding 3. The stator core 1 serves as the magnetic circuit foundation, the insulating frame 2 achieves electrical isolation between the energized winding 3 and the stator core 1, the winding 3 is used to generate a magnetic field when energized, and the phase change heat dissipation component 4, as an independent sealed component, forms a large-area three-dimensional thermal coupling with the winding through its unique geometric design, thereby constructing an efficient heat conduction path from the heat source of the winding directly to the phase change material body. This path effectively avoids the structural and technological challenges caused by constructing complex flow channels in a micro-space.

[0028] Furthermore, the stator core 1 is formed by stacking electrical steel sheets along the axial direction, with multiple radial teeth 101 extending uniformly from its inner circumference, and grooves 102 formed between adjacent teeth 101. This stacked core structure is a well-known technology in the field of motors.

[0029] Based on this, the insulating frame 2 is integrally formed from engineering plastic through injection molding. Its structure tightly covers each tooth 101 of the stator core 1 and the upper and lower end faces of the core to ensure reliable insulation between the winding 3 and the stator core 1. The implementation method of this insulating frame 2 belongs to the prior art.

[0030] Subsequently, the winding 3 is wound with enameled wire onto the insulating frame 2, and then indirectly wound onto the tooth 101. The windings 3 on adjacent teeth 101 are spaced apart in the slots 102 to form multiple circumferentially evenly distributed mating gaps. The existence of these gaps provides structural space for the embedding of the phase change heat dissipation component 4.

[0031] Furthermore, the phase change heat dissipation component 4 is made of a metal material with good thermal conductivity through casting or stamping welding process to form a closed hollow shell. Structurally, it includes an upper ring 401, a lower ring 402, and multiple connecting posts 403 connecting the upper and lower rings 401 and 402. The internal cavities of the upper ring 401, lower ring 402, and connecting posts 403 are interconnected to form a sealed phase change material accommodating cavity. The number, circumferential position, and contour shape of the connecting posts 403 correspond to the mating gap formed between the windings 3. This allows the phase change heat dissipation component 4 to be smoothly fitted and installed on the completed winding stator assembly along the stator axis.

[0032] Subsequently, in the final assembled state, each connecting post 403 of the phase change heat dissipation component 4 is embedded in the corresponding mating gap position, so that the side wall of the connecting post 403 and the side surface of the winding 3 are radially opposite and adjacent. At the same time, the lower surface of the upper ring 401 covers the upper end face of the winding 3, and the upper surface of the lower ring 402 supports the lower end face of the winding 3. In order to eliminate assembly gaps and maximize heat conduction efficiency, thermally conductive insulating materials, such as thermally conductive silicone pads or thermally conductive paste, are filled or coated at all contact interfaces or adjacent interfaces between the side wall of the connecting post 403 and the side of the winding 3, between the lower surface of the upper ring 401 and the upper end of the winding 3, and between the upper surface of the lower ring 402 and the lower end of the winding 3. The purpose of this measure is to fill the microscopic unevenness with a flexible or semi-fluid thermally conductive medium to ensure that a tight physical contact with the heat-generating winding and the phase change heat dissipation component housing is established in all directions with low thermal resistance.

[0033] Furthermore, a phase change material with a specific phase change temperature is vacuum-filled and sealed within the phase change material accommodating cavity. This phase change material is selected from materials with high latent heat of phase change within its phase change temperature range, such as paraffin or hydrated salts. Its phase change temperature point is set within the allowable operating temperature range of the motor winding insulation class but higher than the conventional steady-state operating temperature. The design principle is based on the characteristic that the phase change process absorbs or releases a large amount of latent heat in the isothermal or near-isothermal state of the material.

[0034] During operation, when the motor is energized, especially under high load current, winding 3 generates Joule heat due to resistance. This heat is first rapidly conducted to the metal casing of the phase change heat dissipation component 4 through the directly contacting heat-conducting medium. The heat is then transferred to the phase change material within the cavity through the inner wall of the casing. When the heat flow continues to input, causing the temperature of the inner wall surface closest to the winding to reach the phase change point of the phase change material, the phase change material in the adjacent area begins to transform from a solid to a liquid state. This phase change process absorbs the latent heat of the phase change and stores the instantaneous peak heat generated by the winding as latent heat within the material, thereby effectively suppressing the rapid temperature rise of the winding 3 body. Rapidly rising; when the motor load is reduced or stops working, the heat generation rate of winding 3 decreases or even drops to zero, and the entire stator system begins to dissipate heat to the surrounding environment. The temperature inside the phase change material cavity gradually decreases, and the liquid phase change material will re-solidify into a solid state, while releasing the latent heat of phase change stored in the melting stage. This heat is continuously dissipated through the surface of the metal shell to the air circulating outside the motor or the mounting base, so that the phase change material returns to its initial state where it can absorb heat again. This cyclic working mechanism effectively smooths out the temperature fluctuation peaks of the winding under intermittent and impact loads, and stabilizes the winding operating temperature within a safe range.

[0035] The working process of this device will now be described in the typical application scenario of a "high-powered fan". This fan requires its drive motor to accelerate rapidly from a standstill to a maximum speed of tens of thousands of revolutions per minute in a very short time after receiving the start signal, so as to generate extremely strong wind for blowing in an instant. This high-power acceleration process usually only lasts for a few seconds to tens of seconds, after which the motor may quickly decelerate and stop or enter a low-speed standby state, forming a short-term, high-load, intermittent cyclic working mode.

[0036] Under these harsh operating conditions, traditional heat dissipation methods are inadequate: forced air cooling is slow to respond due to the small internal space of the motor and high airflow resistance, and the low heat capacity of air makes it unable to quickly absorb the high-density heat generated instantaneously; liquid cooling systems are also unsuitable for this kind of instantaneous thermal shock heat dissipation requirements due to thermal inertia and structural complexity.

[0037] The phase change heat dissipation stator of this embodiment exhibits significant advantages in its operation: at the instant the motor is commanded to start and accelerates rapidly, a huge current flows through the winding 3, generating concentrated heat with a high heat flux density.

[0038] At this moment, the phase change heat dissipation component 4 immediately comes into play, and the heat is quickly directed to the phase change material accommodating cavity through the optimized heat conduction path. Since the phase change material (such as paraffin) is selected with a phase change temperature point slightly higher than the normal continuous operating temperature of the motor but much lower than the insulation critical temperature, it begins to absorb a large amount of heat and undergo phase change in the early stage of high load startup, acting like a highly efficient "thermal capacitor", instantly "swallowing" the peak heat that may cause the winding 3 temperature to rise sharply.

[0039] This makes the temperature curve of winding 3 extremely flat, avoiding severe impacts from thermal stress. Even after several or even dozens of such start-stop cycles, the core temperature of winding 3 is still effectively controlled below the safe threshold.

[0040] When the purging task is completed and the motor enters the stop or low-speed stage, the heat stored in the phase change material in the previous stage begins to be released through the surface of the casing into the high-speed airflow (i.e. the strong wind generated by the violent fan itself) flowing outside the motor, and gradually solidifies and resets, preparing for the next working cycle.

[0041] The technological advantages of this device are thus fully demonstrated: it requires no external power or complex piping, and cleverly utilizes the principle of latent heat of phase change to achieve active management and energy buffering of instantaneous high heat flux. It is particularly suitable for micro high-speed motor applications with extremely limited space, harsh heat dissipation conditions and periodic load impacts, and fundamentally solves the stubborn problems of efficiency reduction, accelerated insulation aging and reduced reliability caused by instantaneous overheating in such motors.

[0042] While exemplary embodiments of this disclosure have been described, those skilled in the art will understand that various changes and modifications can be made to the exemplary embodiments of this disclosure without departing from the spirit and scope thereof. Therefore, all changes and modifications are included within the scope of protection of this disclosure as defined by the claims. This disclosure is defined by the appended claims, and equivalents of those claims are also included.

Claims

1. A phase-change heat dissipation motor stator, characterized in that, include: The ring-shaped stator core, the insulating frame fitted on the stator core, the windings wound on the insulating frame, and the phase change heat dissipation components fitted around the windings. The stator core is made of stacked silicon steel sheets, with multiple radial teeth extending evenly along its inner circumference, and grooves formed between adjacent teeth. The insulating frame is made of insulating material and covers the teeth and end faces of the stator core to achieve electrical insulation between the winding and the stator core. The winding is made of conductive material wound on an insulating frame and sleeved on the teeth, with adjacent windings forming a mating gap in the slot; The phase change heat dissipation component is constructed as a closed hollow shell structure, including an upper ring, a lower ring, and multiple connecting posts connecting the upper and lower rings; the internal cavities of the upper ring, lower ring, and connecting posts are interconnected, forming a sealed phase change material accommodating cavity. The number and position of the connecting posts correspond to the fitting gap position, so that the phase change heat dissipation component can be sleeved on the stator core with the winding from top to bottom. In the assembled state, the connecting post of the phase change heat dissipation component is embedded in the mating gap and is adapted to the side profile of the winding; The phase change material accommodating cavity is filled with phase change material, which undergoes a phase change under the heat generated by the motor operation.

2. The phase-change heat dissipation motor stator according to claim 1, characterized in that, The phase change material is paraffin.

3. The phase-change heat dissipation motor stator according to claim 1, characterized in that, Thermally conductive silicone pads or thermally conductive paste are applied between the side of the connecting post and the side of the winding, as well as between the lower surface of the upper ring, the upper surface of the lower ring, and the winding end.

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