A directional heat conduction heat dissipation structure of a dry-type rectifier transformer

Abstract

This invention belongs to the field of transformer technology, specifically relating to a directional heat dissipation structure for a dry-type rectifier transformer. It includes a transformer body; an insulating outer cylinder surrounding the high-voltage winding of the transformer body, forming an axially extending cooling channel spaced apart from the high-voltage winding; a thermal circuit assembly having a heat collector and a heat conductor; the heat collector is positioned above the high-voltage winding, with one end thermally connected to the outer circumferential surface of the high-voltage winding, and the other end spanning the cooling channel and thermally connected to the heat conductor; a cold source is located at the lower part of the cooling channel, used to form a cooling airflow flowing upwards along the cooling channel; the lower end of the heat conductor extends to the outlet area of ​​the cold source. This improves the uniformity of the axial temperature distribution of the high-voltage winding and enhances the utilization efficiency of the low-temperature cooling airflow for the upper heat load.

Description

Technical Field

[0001] This invention belongs to the field of transformer technology, specifically relating to a directional heat dissipation structure for a dry-type rectifier transformer. Background Technology

[0002] During operation, dry-type rectifier transformers continuously generate heat in their windings due to the flow of current. To control the temperature rise of the windings, existing dry-type rectifier transformers typically have ventilation gaps around the windings and cooling fans installed at the bottom of the windings, allowing cooling air to flow upwards from below the windings to remove the heat generated by the windings.

[0003] For dry-type rectifier transformers used in high-altitude areas, the reduced ambient air pressure and density decrease the heat exchange capacity per unit volume of air. Under the same fan operating conditions, the convective cooling effect of the cooling air on the windings is less effective compared to low-altitude environments, thus placing higher demands on the transformer's cooling structure.

[0004] Meanwhile, in traditional bottom-up forced air cooling, the cooling air first passes through the lower part of the winding and continuously absorbs the heat generated by the winding as it flows upward, causing the air temperature to gradually rise. Therefore, by the time the cooling air reaches the upper part of the winding, the temperature difference between it and the winding has decreased, reducing its ability to further dissipate heat to the upper part of the winding. Especially in high-altitude, low-pressure environments, the combined effect of this reduced air heat exchange capacity and the temperature rise along the winding path makes it easier to cause uneven temperature distribution along the axial direction of the winding. Summary of the Invention

[0005] To address the aforementioned problems in the prior art, this invention provides a directional heat dissipation structure for a dry-type rectifier transformer.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A directional heat dissipation structure for a dry-type rectifier transformer is provided, comprising: Transformer body; An insulating outer cylinder is arranged around the high-voltage winding of the transformer body and forms an axially extending cooling channel with the high-voltage winding at intervals. Thermal circuit components, comprising heat collectors and heat conductors; The heat collection element is disposed on the upper part of the high voltage winding, with one end of it being thermally connected to the outer peripheral surface of the high voltage winding, and the other end crossing the cooling channel and being thermally connected to the heat-conducting element. The heat-conducting element is disposed on the inner wall of the insulating outer cylinder and extends downward along the axial direction of the high-voltage winding; A cold source is located at the lower part of the cooling channel to form a cooling airflow that flows from bottom to top along the cooling channel; The lower end of the heat-conducting element extends to the air outlet area of ​​the cold source.

[0007] Preferably, the heat collection element includes: A heat collection bridge spans the cooling channel, with one end being the heat collection end and the other end being the heat transfer end; The heat collection end has an arc-shaped heat collection part facing the high-voltage winding, and the arc-shaped heat collection part is thermally bonded to the outer peripheral surface of the high-voltage winding; The transfer end is thermally connected to the heat-conducting component.

[0008] Preferably, the arc-shaped heat collection part includes a plurality of heat-conducting contact parts spaced apart along the circumference of the high-voltage winding, and the plurality of heat-conducting contact parts are respectively heat-conductingly attached to the outer peripheral surface of the high-voltage winding.

[0009] Preferably, an elastic thermally conductive insulating element is provided between the thermally conductive contact portion and the heat collection bridge, so that the thermally conductive contact portion can generate elastic displacement along the radial direction of the high-voltage winding.

[0010] Preferably, the heat-conducting element is at least partially embedded inside the insulating outer cylinder; The insulating outer cylinder forms a first heat-conducting window at the upper part of the heat-conducting component and a second heat-conducting window at the lower part of the heat-conducting component; the middle part of the heat-conducting component is covered by the insulating outer cylinder. The heat collector is thermally connected to the heat conductor via the first heat-conducting window, and the second heat-conducting window is located in the air outlet area of ​​the cold source.

[0011] Preferably, the heat-conducting component includes a heat-receiving section, a heat-transfer section, and a heat-exchange section arranged sequentially along the axial direction; The heating section is configured corresponding to the first heat conduction window, the heat transfer section is located between the first heat conduction window and the second heat conduction window, and the heat exchange section is configured corresponding to the second heat conduction window.

[0012] Preferably, the outer side of the heat transfer section is covered with an insulating layer with a lower thermal conductivity than the heat transfer section, so as to limit the heat transfer section from dissipating heat radially into the cooling channel.

[0013] Preferably, the heat exchange section forms a plurality of spaced-apart heat-conducting branches along a direction away from the heat transfer section, and a heat exchange gap is formed between adjacent heat-conducting branches for the cooling airflow to pass through.

[0014] Preferably, the insulating outer cylinder is made of an electrically insulating material, the heat collector and the heat conductor are made of electrically insulating and thermally conductive materials, and the thermal conductivity of the heat conductor is greater than that of the insulating outer cylinder.

[0015] Preferably, the outer surface of the heat collection bridge is provided with at least one insulating flange, which protrudes along the outer periphery of the heat collection bridge to increase the surface path length between the heat collection end and the transmission end.

[0016] This invention provides a directional heat dissipation structure for a dry-type rectifier transformer. The beneficial effects of this invention are as follows: The upper part of the heat can be exchanged using the relatively low-temperature cooling airflow, thereby reducing the dependence of the upper region of the high-voltage winding on the already heated cooling airflow. This is beneficial to improving the temperature distribution along the axial direction of the high-voltage winding, reducing the peak temperature rise in the upper region of the high-voltage winding, improving the uniformity of the temperature distribution along the axial direction of the high-voltage winding, and increasing the utilization efficiency of the low-temperature cooling airflow on the upper heat load. Attached Figure Description

[0017] Figure 1 This is one of the perspective views of the directional heat dissipation structure of the dry-type rectifier transformer proposed in this invention; Figure 2 This is the second perspective view of the directional heat dissipation structure of the dry-type rectifier transformer proposed in this invention. Figure 3 This is a front view of the directional heat dissipation structure of the dry rectifier transformer proposed in this invention. Figure 4 This is a front half-sectional view of the directional heat dissipation structure of the dry rectifier transformer proposed in this invention. Figure 5 This is a top view of the directional heat dissipation structure of the dry rectifier transformer proposed in this invention. Figure 6 This is a structural view of the heat collector in the directional heat dissipation structure of the dry rectifier transformer proposed in this invention. Figure 7 This is a cross-sectional view of the insulating outer cylinder in the directional heat dissipation structure of the dry-type rectifier transformer proposed in this invention. Figure 8 This is a structural view of the heat-conducting component in the directional heat dissipation structure of the dry-type rectifier transformer proposed in this invention.

[0018] Explanation of reference numerals in the attached figures: 1. Transformer body; 101. High-voltage winding; 2. Insulating outer cylinder; 3. Cooling channel; 4. Thermal circuit assembly; 401. Heat collector; 4011. Heat collector bridge; 4012. Heat collector end; 4013. Transfer end; 4014. Thermally conductive contact part; 4015. Elastic thermally conductive insulation part; 402. Thermally conductive part; 4021. Heated section; 4022. Heat transfer section; 4023. Heat exchange section; 4024. Thermally conductive support; 5. Cold source; 601. First thermally conductive window; 602. Second thermally conductive window; 7. Insulating flange. Detailed Implementation

[0019] 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 some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Please see Figures 1-8 As shown, the specific embodiments provided by the present invention are as follows: like Figures 2 to 5 As shown, an embodiment of the present invention proposes a directional heat dissipation structure for a dry-type rectifier transformer, which is suitable for heat dissipation of dry-type rectifier transformers.

[0021] Specifically, the directional heat dissipation structure includes a transformer body 1, an insulating outer cylinder 2, a thermal circuit assembly 4, and a cold source 5.

[0022] The transformer body 1 includes an iron core and a winding structure disposed outside the iron core, wherein the winding structure includes a low-voltage winding and a high-voltage winding 101. The high-voltage winding 101 generates heat due to the load current during transformer operation, and therefore needs to be dissipated by an external cooling medium.

[0023] The insulating outer cylinder 2 is arranged around the high-voltage winding 101 and maintains a certain distance from the outer peripheral surface of the high-voltage winding 101, thereby forming a cooling channel 3 between the insulating outer cylinder 2 and the high-voltage winding 101. The cooling channel 3 extends along the axial direction of the high-voltage winding 101, allowing the cooling airflow to flow upward from the lower part of the high-voltage winding 101 through its outer peripheral area, thereby providing forced convection heat dissipation for the high-voltage winding 101.

[0024] The cold source 5 is located at the lower part of the cooling channel 3 and is used to supply cooling airflow to the cooling channel 3. The cooling airflow enters from the lower part of the cooling channel 3 and flows upward along the axial direction of the high-voltage winding 101. During the flow, the cooling airflow exchanges heat with the high-voltage winding 101 to remove the heat generated by the high-voltage winding 101.

[0025] Because the cooling airflow flows from bottom to top, it gradually absorbs heat as it passes through the lower and middle regions of the high-voltage winding 101. This results in the cooling airflow reaching the upper region of the high-voltage winding 101 at a higher temperature compared to when it enters the cooling channel 3. Especially in high-altitude, low-pressure environments, the reduced air density further affects the convective heat transfer capacity of the cooling airflow, leading to relatively poor heat dissipation conditions in the upper region of the high-voltage winding 101.

[0026] To improve the heat dissipation conditions in the upper region of the high-voltage winding 101, this embodiment further includes the thermal circuit assembly 4. The thermal circuit assembly 4 includes a heat collector 401 and a heat conductor 402, wherein the heat collector 401 is disposed in the upper region of the high-voltage winding 101 to collect some of the heat generated in the upper part of the high-voltage winding 101.

[0027] One end of the heat collector 401 forms a thermally conductive connection with the outer peripheral surface of the high-voltage winding 101, allowing the heat generated inside the high-voltage winding 101 and transferred outward to the heat collector 401 via its outer peripheral surface. The other end of the heat collector 401 crosses the cooling channel 3 and forms a thermally conductive connection with the heat conductor 402, thereby establishing a solid thermal conduction path across the cooling channel 3 between the high-voltage winding 101 and the insulating outer cylinder 2.

[0028] The heat-conducting element 402 is disposed on the inner wall of the insulating outer cylinder 2 and extends downward along the axial direction of the high-voltage winding 101. The heat transferred from the heat collector 401 to the heat-conducting element 402 can be transferred along the heat-conducting element 402 towards the lower part of the high-voltage winding 101, so that some of the heat generated in the upper region of the high-voltage winding 101 is no longer completely carried away by the cooling airflow in the upper region, but is transferred to the lower region through the thermal circuit assembly 4.

[0029] Furthermore, the lower end of the heat-conducting element 402 extends to the air outlet area of ​​the cold source 5. Since the cooling airflow in this area has just been output from the cold source 5 and has not yet passed through the main heat exchange area of ​​the high-voltage winding 101, its temperature is relatively low. The heat transferred from the upper area of ​​the high-voltage winding 101 to the lower end of the heat-conducting element 402 can exchange heat with the low-temperature cooling airflow in this area and be carried away by the cooling airflow.

[0030] Therefore, in addition to the traditional bottom-up airflow cooling path, this embodiment forms a solid heat conduction path extending downward from the upper part of the high-voltage winding 101. The cooling airflow flows upward along the high-voltage winding 101, while the thermal path assembly 4 transfers a portion of the heat from the upper part of the high-voltage winding 101 downward in the opposite direction to the outlet area of ​​the cold source 5. This allows the upper heat to be exchanged using the relatively low-temperature cooling airflow, thereby reducing the dependence of the upper region of the high-voltage winding 101 on the already heated cooling airflow. This improves the axial temperature distribution of the high-voltage winding 101, reduces the peak temperature rise in the upper region of the high-voltage winding 101, improves the uniformity of the axial temperature distribution of the high-voltage winding 101, and increases the utilization efficiency of the low-temperature cooling airflow for the upper heat load.

[0031] Meanwhile, the thermal circuit component 4 is mainly located outside the high voltage winding 101, without needing to change the conductor arrangement and main insulation structure inside the high voltage winding 101. Thus, while enhancing heat dissipation, it can better maintain the original electrical insulation system and main structure of the high voltage winding 101.

[0032] like Figure 1 As shown, in a preferred embodiment, the directional heat dissipation structure further includes an exhaust assembly, which is disposed above the high-voltage winding 101 and corresponding to the upper end of the cooling channel 3, for extracting the cooling airflow that flows from bottom to top along the cooling channel 3 outward.

[0033] Specifically, the cold source 5 is located at the lower part of the cooling channel 3 and supplies cooling airflow to the cooling channel 3. The exhaust assembly is located at the upper part of the cooling channel 3 and forms a suction effect on its upper end, so that the lower part of the cooling channel 3 forms the air supply side and the upper part forms the air exhaust side. Thus, the cold source 5 and the exhaust assembly act on the air inlet and air outlet of the cooling channel 3 respectively, which helps to form a pressure difference at both ends of the cooling channel 3 and maintain the cooling airflow from bottom to top along the high-voltage winding 101.

[0034] Meanwhile, the cooling airflow that flows through the upper region of the high-voltage winding 101 can be discharged to the outside in a timely manner under the action of the exhaust assembly, so as to reduce the high-temperature airflow from staying or flowing back above the high-voltage winding 101, which is beneficial to improving the heat exchange conditions in the upper region of the cooling channel 3.

[0035] In another preferred embodiment, the air outlet area of ​​the cold source 5 is formed with a main cooling branch and a bypass heat exchange branch that are separated from each other. The main cooling branch is connected to the lower part of the cooling channel 3 and is used to deliver cooling airflow to the cooling channel 3. The bypass heat exchange branch is arranged corresponding to the lower part of the heat conductor 402 and is isolated from the cooling channel 3.

[0036] The heat exchange section 4023 of the heat-conducting element 402 is at least partially located within the bypass heat exchange branch, allowing the heat transferred downwards from the upper region of the high-voltage winding 101 via the heat path assembly 4 to be released into the cooling airflow flowing through the bypass heat exchange branch. The cooling airflow, having absorbed heat from the heat exchange section 4023, is discharged through the exhaust port of the bypass heat exchange branch and no longer enters the cooling channel 3.

[0037] Therefore, the cooling airflow output by the cold source 5 is divided into a main cooling airflow for cooling the high-voltage winding 101 and a bypass cooling airflow for carrying away the heat transferred by the heat circuit assembly 4, so that the heat transferred from the upper part of the high-voltage winding 101 to the lower part will not be reloaded to the main cooling airflow entering the cooling channel 3, thereby maintaining a low temperature of the cooling airflow entering the cooling channel 3 while using the low-temperature airflow to cool the heat exchange section 4023.

[0038] In one specific embodiment, the cold source 5 includes a cooling fan.

[0039] In one specific embodiment, the insulating outer cylinder 2 is connected to the mounting frame of the transformer body 1 through an insulating support structure, so that the insulating outer cylinder 2 and the high voltage winding 101 are kept at a distance.

[0040] like Figure 6 As shown, in a preferred embodiment, the heat collector 401 includes a heat collector bridge 4011 spanning the cooling channel 3. The heat collector bridge 4011 has a heat collector end 4012 and a transfer end 4013 disposed opposite to each other. The heat collector end 4012 is disposed close to the high-voltage winding 101 and is used to receive heat transferred outward from the outer periphery of the high-voltage winding 101. The transfer end 4013 is disposed towards the insulating outer cylinder 2 and forms a thermally conductive connection with the heat conductor 402 to further transfer the heat acquired by the heat collector end 4012 to the heat conductor 402.

[0041] Specifically, the heat collection end 4012 has an arc-shaped heat collection portion facing the high-voltage winding 101. The shape of the arc-shaped heat collection portion is adapted to the outer peripheral contour of the corresponding position of the high-voltage winding 101, so that the arc-shaped heat collection portion can form a certain range of contact area along the circumference of the high-voltage winding 101. Compared with point or line contact methods, by setting the arc-shaped heat collection portion, the effective thermally conductive contact area between the heat collection end 4012 and the outer peripheral surface of the high-voltage winding 101 can be increased, and the contact thermal resistance between the two can be reduced, thereby facilitating the transfer of heat from the upper region of the high-voltage winding 101 to the heat collection bridge 4011.

[0042] The heat collection bridge 4011 extends from the heat collection end 4012 toward the insulating outer cylinder 2 and crosses the cooling channel 3, so that the heat collection end 4012 and the heat transfer end 4013 are located on both sides of the cooling channel 3. Thus, the heat collection bridge 4011 can establish a radially extending solid heat conduction path between the high-voltage winding 101 and the insulating outer cylinder 2 without changing the internal structure of the high-voltage winding 101.

[0043] The transfer end 4013 is thermally connected to the heat-conducting component 402. When the heat generated in the upper region of the high-voltage winding 101 is transferred to the arc-shaped heat collector, the heat is sequentially transferred through the heat collector end 4012, the heat collector bridge 4011, and the transfer end 4013 to the heat-conducting component 402, and then transferred axially downward by the heat-conducting component 402, thereby realizing that the heat in the upper part of the high-voltage winding 101 is radially drawn out and further transferred axially.

[0044] In a preferred embodiment, the arc-shaped heat collection part includes a plurality of heat-conducting contact parts 4014 arranged circumferentially along the high-voltage winding 101. The plurality of heat-conducting contact parts 4014 are respectively arranged facing the outer peripheral surface of the high-voltage winding 101 and respectively form a heat-conducting fit with the outer peripheral surface of the high-voltage winding 101 at the corresponding position.

[0045] Specifically, multiple thermally conductive contact portions 4014 are arranged sequentially along the circumference of the high-voltage winding 101, with gaps formed between adjacent thermally conductive contact portions 4014. Compared to a structure using a continuous, integrated arc-shaped contact surface, setting the arc-shaped heat collection portion as multiple spaced-apart thermally conductive contact portions 4014 allows each thermally conductive contact portion 4014 to establish thermally conductive contact with different areas of the outer circumferential surface of the high-voltage winding 101, thereby improving the adaptability of the heat collection component 401 to local dimensional deviations and surface shape deviations of the outer circumferential surface of the high-voltage winding 101.

[0046] Meanwhile, since the thermally conductive contact portions 4014 are spaced apart from each other, the overall constraint caused by the thermal expansion difference between the large-area continuous thermally conductive structure and the high-voltage winding 101 can be reduced, so that there is a certain deformation release space between each thermally conductive contact area, thereby reducing the additional stress generated by the heat collection structure on the outer peripheral surface of the high-voltage winding 101 during the thermal cycle.

[0047] During operation, the heat generated in the upper region of the high-voltage winding 101 can be transferred to the heat collection bridge 4011 through multiple thermally conductive contact parts 4014, and then collected by the heat collection bridge 4011 and further transferred to the heat-conducting element 402. Thus, while maintaining a large effective heat collection area, it helps to improve the stability of the thermal connection between the heat collection element 401 and the high-voltage winding 101.

[0048] In a preferred embodiment, an elastic thermally conductive insulating member 4015 is provided between the thermally conductive contact portion 4014 and the heat collection bridge 4011. The elastic thermally conductive insulating member 4015 is connected to the thermally conductive contact portion 4014 and the heat collection bridge 4011 respectively, so that the thermally conductive contact portion 4014 can generate elastic displacement along the radial direction of the high voltage winding 101.

[0049] Specifically, the elastic thermally conductive insulating element 4015 has a certain elastic deformation capacity and thermal conductivity. When there is a local dimensional deviation on the outer peripheral surface of the high-voltage winding 101, or when the high-voltage winding 101 undergoes radial thermal expansion due to temperature rise during operation, the thermally conductive contact portion 4014 can generate a slight radial displacement relative to the heat collection bridge 4011 under the elastic deformation of the elastic thermally conductive insulating element 4015, so as to adapt to the actual position change of the outer peripheral surface of the high-voltage winding 101.

[0050] Meanwhile, the elastic thermally conductive insulating member 4015 can apply an elastic force toward the high-voltage winding 101 to the thermally conductive contact portion 4014, so that the thermally conductive contact portion 4014 remains in contact with the outer peripheral surface of the high-voltage winding 101, reducing the contact gap caused by manufacturing errors, vibration or thermal expansion and contraction, thereby maintaining a stable thermally conductive connection.

[0051] Furthermore, since the elastic thermally conductive insulating element 4015 has electrical insulation properties, it is disposed between the thermally conductive contact portion 4014 and the heat collection bridge 4011. While providing elastic compensation and heat transfer functions, it does not form an additional conductive path, which is beneficial to maintaining the original electrical insulation state of the high-voltage winding 101.

[0052] Therefore, the multiple thermally conductive contact portions 4014 can be independently radially floated and adjusted by the corresponding elastic thermally conductive insulating member 4015, so that each thermally conductive contact portion 4014 can more fully adapt to the local contour of the outer peripheral surface of the high voltage winding 101 and reduce the mechanical stress generated by the rigid contact on the surface of the high voltage winding 101, thereby taking into account heat collection efficiency, fit stability and structural reliability.

[0053] In another preferred embodiment, the thermal circuit assembly 4 includes a plurality of heat collection elements 401 arranged circumferentially along the high voltage winding 101 and at least one heat conduit, the heat conduit being disposed on the insulating outer cylinder 2 and extending circumferentially thereon.

[0054] Multiple heat collectors 401 span the cooling channel 3 and are thermally connected to different positions of the heat collector, so that the heat generated in different circumferential regions on the upper part of the high voltage winding 101 is transferred to the heat collector.

[0055] like Figure 7 As shown, the heat-conducting element 402 is thermally connected to the heat concentrator and extends downward along the axial direction of the insulating outer cylinder 2 from the heat concentrator, so that the heat obtained by the multiple heat collectors 401 can be collected at the heat concentrator and then transferred to the area where the cold source 5 is located via the heat-conducting element 402.

[0056] With the above structure, multiple dispersed heat collection positions can be used to extract heat from different circumferential areas on the upper part of the high voltage winding 101, and the heat collection device can form a unified heat output path, thereby improving the adaptability of the thermal circuit component 4 to local non-uniform temperature fields.

[0057] In a preferred embodiment, the heat-conducting element 402 is at least partially embedded within the insulating outer cylinder 2, so that the insulating outer cylinder 2 can be used to mount and cover the heat-conducting element 402. The heat-conducting element 402 extends axially along the insulating outer cylinder 2, with its upper part corresponding to the heat collector 401 and its lower part extending to the air outlet area of ​​the cold source 5.

[0058] Specifically, the insulating outer cylinder 2 forms a first heat-conducting window 601 on the upper part of the heat-conducting element 402. The first heat-conducting window 601 exposes at least part of the upper part of the heat-conducting element 402 to the cooling channel 3, so that the heat collector 401 and the heat-conducting element 402 can form a thermally conductive connection. Thus, the heat in the upper region of the high-voltage winding 101, after passing through the cooling channel 3 via the heat collector 401, can be transferred to the heat-conducting element 402 through the first heat-conducting window 601.

[0059] The insulating outer cylinder 2 forms a second heat-conducting window 602 at the lower part of the heat-conducting component 402. The second heat-conducting window 602 is located in the air outlet area of ​​the cold source 5, so that the lower part of the heat-conducting component 402 can directly or indirectly exchange heat with the low-temperature cooling airflow output by the cold source 5, so as to release the heat transferred from the upper part of the high-voltage winding 101 to the cooling airflow.

[0060] The middle portion of the heat-conducting element 402, located between the first heat-conducting window 601 and the second heat-conducting window 602, is covered by the insulating outer cylinder 2, allowing this portion to primarily perform the function of axial heat transfer. Compared to exposing the entire length of the heat-conducting element 402 to the cooling channel 3, covering the middle portion of the heat-conducting element 402 with the insulating outer cylinder 2 reduces the premature release of heat into the central region of the cooling channel 3 during downward transfer, allowing more heat to continue downward along the heat-conducting element 402 to the low-temperature cooling area corresponding to the second heat-conducting window 602.

[0061] Thus, the heat-conducting component 402 forms a directional heat transfer path within the insulating outer cylinder 2, which involves heat collection at the top, heat transfer in the middle, and heat release at the bottom. This allows the heat collected by the heat collector 401 at the top of the high-voltage winding 101 to be preferentially transferred to the air outlet area of ​​the cold source 5, thereby improving the heat transfer efficiency of the thermal circuit assembly 4.

[0062] like Figure 8As shown, in a preferred embodiment, the heat-conducting element 402 includes a heat-receiving section 4021, a heat-transfer section 4022, and a heat-exchange section 4023 arranged sequentially along the axial direction. The heat-receiving section 4021 is disposed corresponding to the first heat-conducting window 601, the heat-transfer section 4022 is located between the first heat-conducting window 601 and the second heat-conducting window 602, and the heat-exchange section 4023 is disposed corresponding to the second heat-conducting window 602.

[0063] Specifically, the heated section 4021 is used to receive heat transferred by the heat collector 401. Since the first heat-conducting window 601 exposes the heated section 4021 at least partially to the cooling channel 3, the heat collector 401 can form a thermally conductive connection with the heated section 4021 through the first heat-conducting window 601, so that the heat drawn from the upper region of the high-voltage winding 101 first enters the heated section 4021.

[0064] The heat transfer section 4022 extends downward from the heated section 4021 along the axial direction of the high-voltage winding 101 and is located within the corresponding covered area of ​​the insulating outer cylinder 2. The heat transfer section 4022 is mainly used to transfer the heat received by the heated section 4021 to the lower part of the heat-conducting element 402, so that the heat is transferred axially along the insulating outer cylinder 2, instead of being directly released in the upper region of the high-voltage winding 101.

[0065] The heat exchange section 4023 is thermally connected to the heat transfer section 4022 and is configured corresponding to the second heat conduction window 602. The second heat conduction window 602 is located in the air outlet area of ​​the cold source 5, enabling the heat exchange section 4023 to exchange heat with the low-temperature cooling airflow output from the cold source 5. The heat entering the heat conductor 402 from the heated section 4021 is transferred downwards through the heat transfer section 4022, and can be concentrated and released in the heat exchange section 4023, and carried away by the cooling airflow.

[0066] Thus, the heating section 4021, the heat transfer section 4022, and the heat exchange section 4023 respectively undertake the functions of heat extraction, heat transmission, and heat release, so that the heat-conducting component 402 forms an axial heat-conducting path with clear functional partitions, which is beneficial to directionally transfer part of the heat in the upper region of the high-voltage winding 101 to the air outlet region of the cold source 5 for heat exchange.

[0067] In a preferred embodiment, an insulating heat insulation layer is provided between the heat transfer section 4022 and the insulating outer cylinder 2. The insulating heat insulation layer covers the outside of the heat transfer section 4022 and is connected to the insulating outer cylinder 2. The thermal conductivity of the insulating heat insulation layer is lower than that of the heat transfer section 4022, so as to reduce the radial heat exchange between the heat transfer section 4022 and the surrounding area.

[0068] Specifically, the insulating heat insulation layer extends along the axial direction of the heat transfer section 4022 and at least covers the side of the heat transfer section 4022 facing the cooling channel 3, so that the heat entering the heat transfer section 4022 from the heated section 4021 is not easily released to the cooling channel 3 in advance through the outer peripheral surface of the heat transfer section 4022 during the downward transfer process.

[0069] As the cooling airflow in the cooling channel 3 flows from bottom to top, its temperature gradually increases after passing through the lower and middle regions of the high-voltage winding 101. By providing the insulating heat-insulating layer on the outside of the heat transfer section 4022, ineffective heat exchange between the heat transfer section 4022 and the already heated cooling airflow in the middle region can be reduced, allowing more heat to continue to be transferred downwards along the heat transfer section 4022 to the heat exchange section 4023 corresponding to the air outlet region of the cold source 5.

[0070] Meanwhile, the insulating and heat-insulating layer has electrical insulation properties, which can reduce radial heat loss while maintaining the electrical insulation state of the periphery of the heat-conducting component 402.

[0071] Thus, under the action of the insulating and heat-insulating layer, the heat transfer section 4022 forms a directional heat transfer path with axial heat transfer as the main component, enabling the heat conductor 402 to more concentratedly transport the heat obtained from the upper part of the high voltage winding 101 to the heat exchange section 4023, thereby improving the heat transfer efficiency of the thermal circuit assembly 4.

[0072] In a preferred embodiment, the heat exchange section 4023 forms a plurality of heat-conducting branches 4024 spaced apart from each other in a direction away from the heat transfer section 4022, and a heat exchange gap is formed between adjacent heat-conducting branches 4024 for the cooling airflow to pass through.

[0073] Specifically, each of the multiple heat-conducting branches 4024 forms a heat-conducting connection with the heat transfer section 4022, allowing the heat transferred downwards by the heat transfer section 4022 to enter each of the heat-conducting branches 4024. By configuring the heat exchange section 4023 as multiple separate heat-conducting branches 4024, the effective contact area between the heat exchange section 4023 and the cooling airflow can be increased within a limited installation space, thereby improving the convective heat transfer capacity of the heat exchange section 4023.

[0074] The heat exchange gaps are maintained between adjacent heat-conducting branches 4024, allowing the cooling airflow output from the cold source 5 to pass through the gaps between the multiple heat-conducting branches 4024 and simultaneously exchange heat with the surface of each heat-conducting branch 4024. Compared to using an integral block heat exchange structure, this intermittent structure reduces obstruction to the cooling airflow and increases the contact area between the cooling airflow and the heat exchange section 4023.

[0075] During operation, the heat drawn from the upper region of the high-voltage winding 101 is transferred downward to the heat exchange section 4023 via the heat collector 401, the heat receiving section 4021 and the heat transfer section 4022, and can be further dispersed to multiple heat-conducting branches 4024, and carried away by the low-temperature cooling airflow flowing through the heat exchange gap.

[0076] Therefore, through the cooperation between the multiple heat-conducting branches 4024 and the heat exchange gap, an extended heat exchange structure can be formed in the air outlet area of ​​the cold source 5, so that the heat transferred from the upper part of the high-voltage winding 101 can be more fully released into the cooling airflow, thereby improving the heat exchange efficiency of the lower part of the heat-conducting component 402.

[0077] In a preferred embodiment, the insulating outer cylinder 2 is made of an electrically insulating material, the heat collector 401 and the heat conductor 402 are made of electrically insulating and thermally conductive materials, and the thermal conductivity of the heat conductor 402 is greater than that of the insulating outer cylinder 2.

[0078] Specifically, the insulating outer cylinder 2 is mainly used to enclose the high-voltage winding 101 and form the cooling channel 3, while also providing a foundation for the installation and insulation of the heat-conducting component 402. Therefore, its material preferably meets the requirements for electrical insulation performance, mechanical strength, and heat resistance. The insulating outer cylinder 2 can be made of epoxy glass fiber reinforced material, insulating resin composite material, or other electrical insulation materials suitable for the operating environment of dry-type transformers.

[0079] The heat collector 401 and the heat conductor 402 form a solid heat transfer path extending from the upper part of the high-voltage winding 101 to the air outlet area of ​​the cold source 5. Therefore, while ensuring electrical insulation performance, insulating materials with high thermal conductivity are preferred. The electrical insulating and thermally conductive material can be aluminum nitride, boron nitride, alumina ceramic, or a high thermal conductivity insulating composite material to avoid forming additional conductive paths while achieving heat transfer.

[0080] Furthermore, the thermal conductivity of the heat-conducting element 402 is greater than that of the insulating outer cylinder 2, thus forming a low thermal resistance heat transfer path relative to the insulating outer cylinder 2. Combined with the covering structure in the middle of the heat-conducting element 402, more heat input from the heat collector 401 can be transferred along the heat-conducting element 402 to the heat exchange section 4023. Therefore, a relatively concentrated low thermal resistance heat transfer path can be formed in the insulating outer cylinder 2, allowing the insulating outer cylinder 2 to primarily perform insulation, support, and channel functions, while the heat-conducting element 402 primarily performs directional heat transfer.

[0081] By utilizing the aforementioned material properties differences, the insulating outer cylinder 2 and the thermal circuit assembly 4 form a composite structure that combines an insulating main body with a local high thermal conductivity path. While maintaining the electrical insulation performance of the transformer's periphery, this also helps to improve the efficiency of heat transfer from the upper part of the high voltage winding 101 downwards.

[0082] In a preferred embodiment, the outer surface of the heat collection bridge 4011 is provided with at least one insulating flange 7, which protrudes outward along the outer periphery of the heat collection bridge 4011 to increase the surface path length between the heat collection end 4012 and the transmission end 4013.

[0083] Specifically, the heat collection bridge 4011 spans the cooling channel 3 between the high-voltage winding 101 and the insulating outer cylinder 2, with its heat collection end 4012 positioned close to the high-voltage winding 101 and its transmission end 4013 facing the insulating outer cylinder 2. By providing the insulating flange 7 on the outer surface of the heat collection bridge 4011, a path extending from the heat collection end 4012 to the transmission end 4013 along the surface of the heat collection bridge 4011 can be formed to bypass it, thereby increasing the surface distance of the heat collection bridge 4011 without significantly increasing its radial installation dimensions.

[0084] Furthermore, the insulating flange 7 can be configured as an annular flange extending around the outer periphery of the heat collection bridge 4011, or it can be configured as a protruding structure extending locally along the outer surface of the heat collection bridge 4011. Multiple insulating flanges 7 can be spaced apart along the extension direction of the heat collection bridge 4011 to further increase the surface path length between the heat collection end 4012 and the transmission end 4013.

[0085] When the surface of the heat collection bridge 4011 is affected by environmental factors such as dust, moisture or condensation, a longer surface path helps to reduce the possibility of forming a continuous leakage path along the surface of the heat collection bridge 4011, thereby improving the electrical insulation reliability of the heat collection bridge 4011 when it is installed across the cooling channel 3.

[0086] Therefore, the insulating flange 7 extends the surface insulation path of the heat collection bridge 4011 without changing the main heat conduction path of the heat collection bridge 4011, so that the heat collection bridge 4011 can take into account both the cross-channel heat conduction function and the surface insulation requirements, which is beneficial to improving the stability of the directional heat conduction and heat dissipation structure under high pressure and high altitude environments.

[0087] In one specific embodiment, the heat collector 401 is thermally connected to the high-voltage winding 101 at a location on the outer surface of the resin insulation of the high-voltage winding 101, and the heat collector 401 does not directly contact the winding conductor inside the high-voltage winding 101. The thermal circuit assembly 4 is disposed on the outside of the original main insulation structure of the high-voltage winding 101, so that the thermal circuit assembly 4 establishes a solid heat conduction path without replacing the original main insulation layer of the high-voltage winding 101. Therefore, the impact of the thermal circuit assembly 4 on the internal electric field distribution and main insulation structure of the high-voltage winding 101 can be reduced.

[0088] In one specific embodiment, the heat-conducting component 402 may be pre-embedded within the insulating outer cylinder 2 during the molding process, forming a composite integral structure with the insulating outer cylinder 2; alternatively, after the insulating outer cylinder 2 is molded, an axially extending receiving area is formed at a corresponding position, and the heat-conducting component 402 is assembled within the receiving area. The heat-conducting component 402 may be fixed to the insulating outer cylinder 2 by means of insulating adhesive material, interlocking structure, or covering structure to prevent the heat-conducting component 402 from detaching from the insulating outer cylinder 2.

[0089] In one specific embodiment, the first heat-conducting window 601 and the second heat-conducting window 602 may be formed on the side of the insulating outer cylinder 2 facing the cooling channel 3, and may be configured as strip-shaped, rectangular, or other shapes corresponding to the heat-conducting element 402. The first heat-conducting window 601 is used to form a heat-conducting connection area between the heat-collecting element 401 and the heated section 4021, and the second heat-conducting window 602 is used to form a heat exchange area between the heat exchange section 4023 and the cooling airflow. The edges of the first heat-conducting window 601 and the second heat-conducting window 602 may have rounded or chamfered corners to reduce local stress concentration at corresponding positions on the insulating outer cylinder 2.

[0090] In one specific embodiment, a thermally conductive insulating connection layer is provided between the transmission end 4013 of the heat collection bridge 4011 and the heat-conducting component 402. The thermally conductive insulating connection layer is respectively attached to the transmission end 4013 and the heat-conducting component 402. The thermally conductive insulating connection layer can be made of a highly thermally conductive insulating material with a certain degree of flexibility to fill the small assembly gap between the transmission end 4013 and the heat-conducting component 402, and to accommodate the slight relative displacement generated by the two during temperature changes, thereby maintaining a stable thermally conductive connection.

[0091] In one specific embodiment, the thermal circuit assembly 4 can be configured as one or more sets. When multiple sets of the thermal circuit assembly 4 are provided, the multiple sets of the thermal circuit assembly 4 are arranged at circumferential intervals along the high-voltage winding 101, each heat collector 401 corresponds to a different circumferential region on the upper part of the high-voltage winding 101, and each heat conductor 402 extends downward along the insulating outer cylinder 2. The arrangement position of each thermal circuit assembly 4 can be determined according to the actual temperature distribution of the high-voltage winding 101, so that the heat collector 401 is preferentially arranged to correspond to the relatively high temperature region.

[0092] Furthermore, the shape and size of the heat collection bridge 4011, the heat-conducting element 402, and the heat-conducting support 4024 can be determined based on the radial width of the cooling channel 3, the outer diameter of the high-voltage winding 101, and the amount of heat to be transferred. While ensuring sufficient heat conductivity, the projected area of ​​the heat collection bridge 4011 in the direction of the cooling airflow is preferably kept small to reduce its impact on the original cooling airflow after it spans the cooling channel 3.

[0093] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A directional heat dissipation structure for a dry-type rectifier transformer, characterized in that, include: Transformer body; An insulating outer cylinder is arranged around the high-voltage winding of the transformer body and forms an axially extending cooling channel with the high-voltage winding at intervals. Thermal circuit components, comprising heat collectors and heat conductors; The heat collection element is disposed on the upper part of the high voltage winding, with one end of it being thermally connected to the outer peripheral surface of the high voltage winding, and the other end crossing the cooling channel and being thermally connected to the heat-conducting element. The heat-conducting element is disposed on the inner wall of the insulating outer cylinder and extends downward along the axial direction of the high-voltage winding; A cold source is located at the lower part of the cooling channel to form a cooling airflow that flows from bottom to top along the cooling channel; The lower end of the heat-conducting element extends to the air outlet area of ​​the cold source.

2. The directional heat dissipation structure for a dry-type rectifier transformer according to claim 1, characterized in that, The heat collection element includes: A heat collection bridge spans the cooling channel, with one end being the heat collection end and the other end being the heat transfer end; The heat collection end has an arc-shaped heat collection part facing the high-voltage winding, and the arc-shaped heat collection part is thermally bonded to the outer peripheral surface of the high-voltage winding; The transfer end is thermally connected to the heat-conducting component.

3. The directional heat dissipation structure for a dry-type rectifier transformer according to claim 2, characterized in that, The arc-shaped heat collection part includes a plurality of heat-conducting contact parts spaced apart along the circumference of the high-voltage winding, and the plurality of heat-conducting contact parts are respectively heat-conductingly attached to the outer peripheral surface of the high-voltage winding.

4. The directional heat dissipation structure for a dry-type rectifier transformer according to claim 3, characterized in that, An elastic thermally conductive insulating element is provided between the thermally conductive contact portion and the heat collection bridge, so that the thermally conductive contact portion can generate elastic displacement along the radial direction of the high-voltage winding.

5. The directional heat dissipation structure for a dry-type rectifier transformer according to claim 1, characterized in that, The heat-conducting element is at least partially embedded in the insulating outer cylinder; The insulating outer cylinder forms a first heat-conducting window at the upper part of the heat-conducting component and a second heat-conducting window at the lower part of the heat-conducting component; the middle part of the heat-conducting component is covered by the insulating outer cylinder. The heat collector is thermally connected to the heat conductor via the first heat-conducting window, and the second heat-conducting window is located in the air outlet area of ​​the cold source.

6. The directional heat dissipation structure for a dry-type rectifier transformer according to claim 5, characterized in that, The heat-conducting component includes a heat-receiving section, a heat-transfer section, and a heat-exchange section arranged sequentially along the axial direction. The heating section is configured corresponding to the first heat conduction window, the heat transfer section is located between the first heat conduction window and the second heat conduction window, and the heat exchange section is configured corresponding to the second heat conduction window.

7. The directional heat dissipation structure for a dry-type rectifier transformer according to claim 6, characterized in that, The outer side of the heat transfer section is covered with an insulating layer with a lower thermal conductivity than the heat transfer section, so as to limit the heat transfer section from dissipating heat radially into the cooling channel.

8. The directional heat dissipation structure for a dry-type rectifier transformer according to claim 7, characterized in that, The heat exchange section forms multiple spaced-apart heat-conducting branches in a direction away from the heat transfer section, and a heat exchange gap is formed between adjacent heat-conducting branches for the cooling airflow to pass through.

9. The directional heat dissipation structure for a dry-type rectifier transformer according to claim 1, characterized in that, The insulating outer cylinder is made of an electrically insulating material, and the heat collector and the heat conductor are made of electrically insulating and thermally conductive materials, with the thermal conductivity of the heat conductor being greater than that of the insulating outer cylinder.

10. The directional heat dissipation structure for a dry-type rectifier transformer according to claim 1, characterized in that, The outer surface of the heat collection bridge is provided with at least one insulating flange, which protrudes along the outer periphery of the heat collection bridge to increase the surface path length between the heat collection end and the transmission end.

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