Heat pipe for high-voltage coil and manufacturing method thereof

Abstract

The invention discloses a heat pipe for a high-voltage coil and a manufacturing method of the heat pipe, and belongs to the technical field of heat dissipation of high-voltage equipment. The heat pipe comprises a conductive evaporation spiral pipe section, a liquid return section and a condensation section, two terminals are arranged on the outer wall of the evaporation spiral pipe section and are used for being connected with an internal circuit of high-voltage equipment; the liquid return section is communicated with the evaporation spiral pipe section to form a closed loop, and the closed loop is used for circulation of a working medium; the condensation section is communicated with the closed loop, and the condensation section is used for condensing the evaporated working medium in the evaporation spiral pipe section and enabling the condensed working medium to flow to the liquid return section. The heat generated by the heat pipe can be directly transferred into the working medium in the heat pipe, so that the frequency of interface heat transfer is reduced, and the cooling efficiency of the heat pipe for the high-voltage coil is improved; and on the other hand, the condensed working medium can directly return to the bottom of the evaporation spiral pipe section from the liquid return section, the influence of the backflow condensation working medium on steam is reduced, the heat transfer limit of the heat pipe is greatly improved, and the cooling and heat dissipation effects are effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of heat dissipation of high-voltage equipment, and particularly relates to a heat pipe for high-voltage coil and a manufacturing method thereof. BACKGROUND

[0002] The heat pipe is a new heat transfer element with extremely high heat conductivity, which transfers heat through evaporation and condensation of liquid in a fully closed vacuum pipe to achieve good cooling effect. The heat pipe has the characteristics of extremely high heat conductivity, good isothermality, changeable heat transfer area on the cold and hot sides, long-distance heat transfer, controllable temperature, etc. Among many heat transfer methods, the heat pipe is one of the most effective heat transfer methods. Since it was first applied in the 1960s, the heat pipe has been widely used in various fields.

[0003] The high-voltage coil is an important element of power equipment, and the transformer and the reactor cannot be separated from the coil. The cooling method of the high-voltage coil basically adopts air cooling, insulation gas cooling, oil cooling and water cooling. For the transformer, the low-voltage coil is generally single-layer winding and is wound from high to low (or from left to right), and the high-voltage coil is generally multi-layer winding, i.e. multi-layer winding is wound from inside to outside. It is particularly difficult to use the heat pipe to cool the high-voltage coil due to the long length, small diameter of the metal pipe and the multi-layer winding arrangement.

[0004] In order to solve the problem of cooling and heat dissipation, the prior art discloses a variety of traditional ideas, some of which are, for example, a heat pipe cooling method for oil-immersed transformers (application number 200920203657.2), which cools the transformer oil through a heat pipe, thereby achieving the purpose of coil cooling; some of which are, for example, a dry-type transformer cooled by a heat pipe (application number 95241533.X), which cools the air around the coil through a heat pipe buried between the core and the high-low voltage winding, thereby achieving the purpose of coil cooling; some of which are, for example, a heat pipe cooling method for gas-insulated power transformers (application number 201310122434.4), which cools the insulating gas around the coil through two heat pipes, thereby achieving the purpose of coil cooling. The above technologies all demonstrate the feasibility of successfully applying heat pipes to high-voltage equipment cooling, but the heat source in high-voltage equipment is external to the heat pipe, and the heat generated by it needs to be transmitted to the working medium in the heat pipe at least through the heat pipe wall, so the cooling efficiency needs to be improved. Some new ideas of the prior art, such as a heat pipe for high-voltage equipment and a manufacturing method thereof (application number 202410582056.6), replace the original heating wire with a new heat source, i.e., an evaporation segment body with cooling liquid, to improve the cooling efficiency of the heat pipe and achieve the purpose of coil cooling. However, when the above scheme is applied to high-voltage coils with a large number of turns and a very long copper pipe (for example, at least 500 meters long), it is found after repeated tests that due to the low slope of each turn, the falling of water vapor makes it difficult for the generated steam to rise, greatly limiting the heat transfer limit of the heat pipe and reducing the cooling and heat dissipation effect. SUMMARY

[0005] The present application provides a heat pipe for high-voltage coils and a manufacturing method thereof, aiming to solve the problem of poor cooling and heat dissipation effect of high-voltage coils, and to improve the cooling and heat dissipation effect.

[0006] The first aspect of the present application provides a heat pipe for high-voltage coils, comprising:

[0007] The evaporation spiral pipe segment is electrically conductive, and two wire terminals are arranged on the outer wall of the evaporation spiral pipe segment, the two wire terminals being used for connecting with the internal circuit of the high-voltage equipment;

[0008] The liquid return segment is in communication with the evaporation spiral pipe segment and forms a closed loop, and the closed loop is used for circulating flow of the working medium between the liquid return segment and the evaporation spiral pipe segment;

[0009] The condensation segment is in communication with the closed loop, and the condensation segment is used for condensing the vapor state working medium evaporated in the evaporation spiral pipe segment and making the condensed liquid state working medium flow to the liquid return segment.

[0010] In some embodiments of the first aspect, the evaporation coil section comprises one electrically conductive coil, and two ends of the electrically conductive coil are respectively connected with the liquid return section.

[0011] In the spiral axis of the electrically conductive coil, two connection terminals are respectively located at two ends of the electrically conductive coil.

[0012] In some embodiments of the first aspect, the evaporation coil section comprises a plurality of electrically conductive coils, and the plurality of electrically conductive coils are connected in sequence.

[0013] Each of the electrically conductive coils has an outlet for the flow of the vaporized working medium and an inlet for the flow of the liquid working medium.

[0014] In the connection sequence of the electrically conductive coils, the plurality of electrically conductive coils are sequentially set as a first electrically conductive coil,..., and an nth electrically conductive coil.

[0015] The outlet of the first electrically conductive coil is connected with the liquid return section, and the inlet of the nth electrically conductive coil is connected with the liquid return section.

[0016] One of the connection terminals is located on the first electrically conductive coil, and the other connection terminal is located on the nth electrically conductive coil.

[0017] In some embodiments of the first aspect, the plurality of electrically conductive coils are arranged in parallel.

[0018] The inlet of the ith electrically conductive coil and the inlet of the (i+1)th electrically conductive coil are connected with the liquid return section through a first three-way pipe.

[0019] The outlet of the jth electrically conductive coil and the outlet of the (j+1)th electrically conductive coil are connected with the liquid return section through a second three-way pipe.

[0020] Wherein, n≥3; i is an odd number less than n; j is an even number less than n.

[0021] In some embodiments of the first aspect, the first three-way pipe and the second three-way pipe are Y-shaped three-way pipes.

[0022] In some embodiments of the first aspect, the plurality of electrically conductive coils are arranged in series along the same axis.

[0023] The inlet of the rth electrically conductive coil and the outlet of the (r+1)th electrically conductive coil are connected with the liquid return section through a third three-way pipe.

[0024] Wherein, n≥2; r is a number less than n.

[0025] In some embodiments of the first aspect, the electrically conductive coil is wound by a metal pipe.

[0026] Or the conductive spiral tube is made of metal material 3D printing.

[0027] In some embodiments of the first aspect, the liquid return section is an insulated liquid return section.

[0028] The evaporation spiral tube section is wrapped with an insulation layer.

[0029] The working medium in the heat pipe for high-voltage coil has electrical insulation characteristics when it is in liquid state.

[0030] In some embodiments of the first aspect, the heat pipe for high-voltage coil further comprises an insulated and heat-insulated section.

[0031] The insulated and heat-insulated section is connected between the evaporation spiral tube section and the condensation section, and the length of the insulated and heat-insulated section is greater than the electrical insulation distance of the internal circuit of the high-voltage device.

[0032] The second aspect of the present application provides a manufacturing method of a heat pipe for high-voltage coil, which is used for manufacturing the heat pipe for high-voltage coil of the first aspect, and comprises the following steps:

[0033] Two wiring terminals are respectively installed on two positions of the evaporation spiral tube section.

[0034] The evaporation spiral tube section and each section are sequentially sealed and assembled to form a heat pipe body with a closed loop.

[0035] The heat pipe body is subjected to vacuum treatment until a first preset vacuum degree is reached in the heat pipe body.

[0036] The working medium to be filled is filled into the heat pipe body until the working medium in the heat pipe body reaches a preset height.

[0037] The heat pipe body is subjected to vacuum treatment until a second preset vacuum degree is reached in the heat pipe body, so as to obtain the heat pipe for high-voltage coil.

[0038] From the above technical solutions, the present application has the following advantages:

[0039] The embodiment provides a heat pipe for a high-voltage coil and a manufacturing method thereof, which comprises an evaporation spiral pipe section and a liquid return section, two wire connection ends are arranged on the outer wall of the evaporation spiral pipe section, the two wire connection ends are used for being connected with internal circuits of a high-voltage device, the liquid return section is in communication with the evaporation spiral pipe section to form a closed loop, and the closed loop is used for circulating a working medium, so that after the evaporation spiral pipe section is connected into the internal circuits of the high-voltage device, the evaporation spiral pipe section can be regarded as a pipe type coil connected into the circuits, on one hand, heat generated by the evaporation spiral pipe section can be directly transmitted to the working medium in the heat pipe, the number of interface heat transmission is reduced, and the cooling efficiency of the heat pipe for the high-voltage coil is improved; on the other hand, condensed working medium can directly return to the bottom of the evaporation spiral pipe section from the liquid return section, the influence of the condensed working medium on the return flow is reduced, the rising of the steam is facilitated, the heat transfer limit of the heat pipe is greatly improved, and the cooling and heat dissipation effect is effectively improved. BRIEF DESCRIPTION OF DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0041] Figure 1 It is a schematic diagram of a traditional heat pipe structure;

[0042] Figure 2 It is a schematic diagram of fluid flow of a traditional heat pipe;

[0043] Figure 3 It is a schematic diagram of another traditional heat pipe structure;

[0044] Figure 4 It is a schematic diagram of the overall structure provided by the embodiment one of the present application;

[0045] Figure 5 It is a schematic diagram of fluid flow provided by the embodiment one of the present application;

[0046] Figure 6 It is a schematic diagram of the overall structure provided by the embodiment two of the present application.

[0047] Reference signs:

[0048] 1, Evaporation coil segment; 10, Conductive coil; 100, Steam outlet; 101, Liquid inlet; 11, Connection terminal; 2, Condensation segment; 3, Liquid return segment; 4, Insulation and heat insulation segment; 5, Power supply; 6, Gaseous working medium; 7, Liquid working medium; 1a, Evaporation segment; 1b, Evaporation segment of traditional gravity type heat pipe; 1c, Heat insulation segment of traditional gravity type heat pipe; 1d, Condensation segment of traditional gravity type heat pipe; 1e, Body of traditional gravity type heat pipe; 1f, Gaseous working medium in traditional gravity type heat pipe; 1g, Liquid working medium in traditional gravity type heat pipe; A, Electrically insulated area; B, Area with electric charge. DETAILED DESCRIPTION

[0049] In order to make the invention purposes, features and advantages of the present application more obvious and easy to understand, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the embodiments described below are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0050] High-voltage coil is an important component of power equipment, and transformers and reactors cannot be separated from coils. The cooling methods of high-voltage coils basically adopt air cooling, insulation gas cooling, oil cooling and water cooling. For transformers, low-voltage coils are generally single-layer windings and are wound from high to low (or from left to right), and high-voltage coils are generally multi-layer windings, i.e. multi-layer windings are wound from inside to outside. It is particularly difficult to use heat pipes to cool high-voltage coils due to their long length, small metal tube diameter and multi-layer winding arrangement.

[0051] Prior art as shown in Figure 1 A structure in which an evaporation segment 1a and a condensation segment 2 are arranged in the same pipe has been disclosed. However, when this structure is applied to a high-voltage coil with a large number of turns and a very long copper tube (for example, at least 500 meters long), it is found through repeated tests that due to the low slope of each turn, the falling of water vapor easily causes the generated steam to be difficult to rise (as shown in Figure 2 The path of gaseous working medium 6 and liquid working medium 7 in the steam segment completely coincides, which greatly limits the heat transfer limit of the heat pipe and reduces the cooling and heat dissipation effect.

[0052] In addition, the applicant has not found any prior art of directly using a heat pipe to cool a high-voltage coil. Therefore, the present embodiment provides a heat pipe for high-voltage coils and a manufacturing method thereof, which is used to solve the problem of poor cooling and heat dissipation effect of high-voltage coils in the prior art, so as to improve the cooling and heat dissipation effect.

[0053] Embodiment one

[0054] Please refer to Figure 4 andFigure 5 The first embodiment of the present application provides a heat pipe for high-voltage coil, comprising:

[0055] The evaporation coil segment 1 is electrically conductive, and two wire terminals 11 are arranged on the outer wall of the evaporation coil segment 1, and the two wire terminals 11 are used for connecting with the internal circuit of the high-voltage device;

[0056] The liquid return segment 3 is in communication with the evaporation coil segment 1 to form a closed loop, and the closed loop is used for circulating flow of the working medium between the liquid return segment 3 and the evaporation coil segment 1;

[0057] The condensation segment 2 is in communication with the closed loop, and the condensation segment 2 is used for condensing the vaporized working medium 6 in the evaporation coil segment 1, and making the condensed liquid working medium 7 flow to the liquid return segment 3.

[0058] It can be understood that the heat pipe at least comprises the evaporation coil segment 1, the condensation segment 2 and the liquid return segment 3, the evaporation coil segment 1 is in communication with the liquid return segment 3 to form a closed loop, and the condensation segment 2 is in communication with the closed loop and is located above the evaporation coil segment 1 to condense the working medium; the evaporation coil segment 1 is used as a self-heating source for electrically connecting the high-voltage device, that is, it plays a role as a part of the high-voltage device and also plays a role of heat absorption and cooling, the working medium in the evaporation coil segment 1 is used for absorbing heat of the self-heating source, the working medium is vaporized to form the vaporized working medium 6, and the vaporized working medium 6 is condensed and then reabsorbed; the condensation segment 2 is used for condensing the working medium vaporized in the evaporation coil segment 1 and ensuring that the condensed working medium can flow back to the liquid return segment 3; and the liquid return segment 3 is used for smoothly flowing the condensed working medium to the bottom of the evaporation coil segment 1, so that the working medium in the evaporation coil segment 1 is smoothly vaporized and reabsorbed; the bodies of the segments of the heat pipe can be assembled by using a threaded connection, welding, a clamping sleeve connection, a quick connector or the like.

[0059] It should be noted that the heat pipe provided in the embodiment can be any structure type of heat pipe such as a gravity type heat pipe, a cored heat pipe, a rotating heat pipe, an electrohydrodynamic heat pipe, a magnetohydrodynamic heat pipe and the like; the heat pipe in the embodiment is a gravity type heat pipe, after the evaporation coil segment 1 is connected into the circuit of the current component of the high-voltage device, the whole heat pipe needs to be kept in a preset placement angle range (for example, needs to be kept vertically arranged), so as to ensure that the gas generated in the evaporation coil segment 1 goes up, and ensure that the condensed liquid working medium 8 can be naturally returned to the liquid return segment 3 under the action of gravity; of course, the evaporation coil segment 1 and the liquid return segment 3 can each be arranged with a pipe line with a fluid pump to be in communication with the condensation segment 2, so as to realize fluid flow in a mechanical mode.

[0060] In the actual application of the embodiment, Figure 4 It can be seen that Figure 4In the working process of the embodiment, the heat generated by the evaporation spiral pipe section 1 can be directly transferred to the working medium in the heat pipe, the working medium is evaporated to form the vapor state working medium 6, and the condensed reflux liquid working medium 8 is formed after the vapor state working medium 6 is condensed. When the condensed reflux liquid working medium 8 flows back, because the flow resistance in the evaporation spiral pipe section 1 is large and the flow resistance of the liquid return section 3 is small, most of the condensed reflux liquid working medium 8 flows back to the bottom of the evaporation spiral pipe section 1 through the liquid return section 3, so that the cycle operation is realized.

[0061] In the working process of the embodiment, the heat generated by the evaporation spiral pipe section 1 can be directly transferred to the working medium in the heat pipe, the working medium is evaporated to form the vapor state working medium 6, and the condensed reflux liquid working medium 8 is formed after the vapor state working medium 6 is condensed. When the condensed reflux liquid working medium 8 flows back, because the flow resistance in the evaporation spiral pipe section 1 is large and the flow resistance of the liquid return section 3 is small, most of the condensed reflux liquid working medium 8 flows back to the bottom of the evaporation spiral pipe section 1 through the liquid return section 3, so that the cycle operation is realized.

[0062] It should be pointed out that in actual application, the circuit characteristics of the high-voltage equipment current-carrying component, the current-carrying element parameters, the load requirements and the influence of the evaporation spiral pipe section 1 resistance should be analyzed in detail, and the appropriate specification of the evaporation spiral pipe section 1 should be selected, and if necessary, simulation calculation or test verification should be carried out, to ensure that the evaporation spiral pipe section 1 can meet the capacity of the high-voltage equipment design.

[0063] From the above working process, on the one hand, because the heat generated by the evaporation spiral pipe section 1 can be directly transferred to the working medium in the heat pipe, the number of interface heat transfer is reduced, and the cooling efficiency of the heat pipe for the high-voltage coil is improved; on the other hand, because the condensed working medium can directly return to the bottom of the evaporation spiral pipe section 1 from the liquid return section 3, the influence of the condensed working medium on the steam is reduced, which is helpful for the rising of the steam, greatly improves the heat transfer limit of the heat pipe, and effectively improves the cooling and heat dissipation effect.

[0064] Compared with the prior art, the advantages of the embodiment are that the cooling and heat dissipation effect of the high-voltage coil is good. On the one hand, the heat source of the high-voltage coil in the prior art is external to the heat pipe, and the heat generated by the heat source needs to be at least transferred to the working medium in the heat pipe through the heat pipe wall, while in the present application, the heat source of the high-voltage coil is the heat pipe itself, which can directly cool and dissipate heat for itself. On the other hand, the evaporation section and the reflux section are arranged in some prior art, which makes it difficult for the working medium to condense and flow back, while in the present application, the evaporation section and the reflux section are arranged separately, and when the working medium condenses and flows back, it can flow to the evaporation spiral pipe section 1 through the liquid return section 3 with small flow resistance, and the working medium condenses and flows back, and the steam rises smoothly, which helps to improve the heat transfer limit of the heat pipe and effectively improves the cooling and heat dissipation effect.

[0065] In a specific embodiment, as shown in FIG. 1, the evaporation spiral pipe section 1 is connected to the high-voltage coil 2 through the high-voltage electric connection 4. Figure 4As shown, further provided is a structure of the evaporation coil segment 1, which includes an electrically conductive coil 10 with two open ends, and the two ends of the electrically conductive coil 10 are respectively connected with the liquid return segment 3; on the spiral axis of the electrically conductive coil 10, two wire ends 11 are respectively located at the two ends of the electrically conductive coil 10; in a specific implementation, after the two wire ends 11 are connected with the high-voltage equipment, the electrically conductive coil 10 can be regarded as a pipe-shaped coil connected in the circuit, and the heat generated by the electrically conductive coil 10 is transferred to the working medium in the electrically conductive coil 10 and is used for heat absorption and evaporation.

[0066] In the embodiment, the electrically conductive coil 10 can be a circular coil body or a special-shaped coil body, and the electrically conductive coil 10 can be made by winding a metal pipe or by 3D printing of a metal material; the number of turns of the electrically conductive coil 10 is 520 turns, the wire length is 748 meters, and the turns are densely and intricately wound into a coil, and the slope of each turn is very low; the diameter of the copper pipe of the high-voltage winding is Φ = 2 mm; the metal for manufacturing the electrically conductive coil 10 has the characteristics of good electrical conductivity, such as copper, copper alloy, aluminum, silver, etc.; in order to increase the contact area between the evaporation coil segment 1 and the working medium and to strengthen the heat exchange between the evaporation coil segment 1 and the liquid working medium 8, an auxiliary heat dissipation structure, such as fins, ribs, porous structures, etc., can be arranged on the inner side of the evaporation coil segment 1.

[0067] In the embodiment, the wire end 11 can be an electrically conductive connecting piece such as a pin, a pipe clamp, a patch, a soldering sheet, a screw, etc., and can be connected with the evaporation coil segment 1 in an electrically connected form such as welding, pressure connection, winding connection, threaded connection, plug-in connection, etc.; the two wire ends 11 can be respectively arranged at two opposite positions of the evaporation coil segment 1, such as one wire end 11 is arranged at a position close to one end of the evaporation coil segment 1, and the other wire end 11 is arranged at a position close to the other end of the evaporation coil segment 1, so that the heat generated at each position of the evaporation coil segment 1 is uniform.

[0068] In another conventional heat pipe, such as Figure 3 As shown, another conventional heat pipe includes a conventional gravity-type heat pipe evaporation segment 1b, a conventional gravity-type heat pipe adiabatic segment 1c, a conventional gravity-type heat pipe condensation segment 1d, a conventional gravity-type heat pipe body 1e, a gaseous working medium 1f in the conventional gravity-type heat pipe, and a liquid working medium 1g in the conventional gravity-type heat pipe, and each segment in the conventional heat pipe is made of the same metal (such as stainless steel or copper) and lacks the necessary electrical insulation characteristics, and such a heat pipe cannot be applied to the cooling of live conductors inside high-voltage electrical equipment.

[0069] In order to solve the problem of lack of necessary electrical insulation of the traditional heat pipe, in a specific embodiment, in order to improve the insulation performance of the whole high-voltage coil heat pipe, so that the heat pipe can be applied to high-voltage equipment, the return liquid section 3 is an insulating return liquid section 3; the evaporation spiral pipe section 1 is wrapped with an insulating layer, specifically, the return liquid section 3 can be made of insulating materials such as plastic, ceramic, high-temperature silicone and the like; and the insulating layer can be wrapped outside the evaporation spiral pipe section 1 in the form of an insulating material coating layer, an insulating paint coating layer or a spraying layer, an injection molding insulating shell, and a non-solid insulating material pouring, etc.

[0070] In an embodiment, in order to further improve the insulation performance of the whole high-voltage coil heat pipe, the working medium in the high-voltage coil heat pipe is a working medium with electrical insulation characteristics when it is in liquid state, which can be deionized water, acetone, ammonia, etc.; the liquid working medium 8 in the heat pipe is at least filled in the evaporation spiral pipe section 1 to ensure that the evaporation spiral pipe section 1 can be completely cooled, and the risk of high-temperature damage to the evaporation spiral pipe section 1 is reduced.

[0071] Based on the above embodiment, in an embodiment, in order to further improve the insulation performance of the whole high-voltage coil heat pipe, the high-voltage coil heat pipe further comprises an insulating and heat-insulating section 4; the evaporation spiral pipe section 1, the insulating and heat-insulating section 4 and the condensing section 2 are connected in sequence, and in specific implementation, the setting of the insulating and heat-insulating section 4 can reduce the heat transferred from the evaporation spiral pipe section 1 to the condensing section 2, and make the condensing section 2 and the evaporation spiral pipe section 1 maintain electrical insulation.

[0072] In the embodiment, the length of the insulating and heat-insulating section 4 is greater than the electrical insulation distance of the internal circuit of the high-voltage equipment, and in specific implementation, the length of the insulating and heat-insulating section 4 should be greater than the electrical insulation distance of the high-voltage equipment, so that the condensing section 2 and the evaporation spiral pipe section 1 maintain a distance greater than the electrical insulation distance, so that the evaporation spiral pipe section 1 as a whole is in the live area B and the condensing section 2 as a whole is in the electrical insulation area A.

[0073] In the embodiment, the insulating and heat-insulating section 4 is a pipe body open at both ends, which can be a circular pipe body or a special-shaped pipe body; the insulating and heat-insulating section 4 is made of high-temperature resistant insulating materials such as plastic, ceramic, high-temperature silicone and the like.

[0074] In a specific embodiment, the structure of the return liquid section 3 is further provided, the whole profile of the return liquid section 3 is C-shaped, the return liquid section 3 can be a circular pipe body or a special-shaped pipe body, and the pipe body of the return liquid section 3 is vertically arranged, for example, the top of the C-shaped section is located above the evaporation spiral pipe section 1, and the bottom of the C-shaped section is located below the evaporation spiral pipe section 1, so that the working medium can flow under the action of its own gravity and air pressure, of course, various valves or pump bodies can be connected to the pipe body of the return liquid section 3 to promote the flow of the return liquid working medium 8.

[0075] In a specific embodiment, the structure of the condensing section 2 is further provided, which can be a pipe body with one end open and the other end closed, the open end being communicated with the insulation section 4 or the evaporation spiral pipe section 1, and the outer wall of the pipe body being provided with auxiliary heat dissipation structures, such as fins, ribs, porous structures, etc., connected with the refrigeration mechanism for guiding cold, so that the vapor working medium in the condensing section 2 is condensed by the refrigeration mechanism, and the vapor working medium can be condensed to form the reflux liquid working medium 8.

[0076] Embodiment Two

[0077] Please refer to Figure 6 The second embodiment of the present application provides a heat pipe for high-voltage coil, which is basically the same as the first embodiment, and the difference lies in that the specific structure of the evaporation spiral pipe section 1 is different, that is, the evaporation spiral pipe section 1 in the second embodiment includes a plurality of conductive spiral pipes 10, rather than the evaporation spiral pipe section 1 in the first embodiment including one conductive spiral pipe 10.

[0078] In a specific embodiment, the structure of the evaporation spiral pipe section 1 is further provided, which includes a plurality of conductive spiral pipes 10 connected in sequence; each conductive spiral pipe 10 has a steam outlet end 100 at the axial end for the outflow of the vapor working medium 6 and a liquid inlet end 101 for the inflow of the liquid working medium 8; along the communication sequence of the conductive spiral pipes 10, the plurality of conductive spiral pipes 10 are sequentially set as a first conductive spiral pipe 10,..., an n-th conductive spiral pipe 10; the steam outlet end 100 of the first conductive spiral pipe 10 is communicated with the liquid return section 3, and the liquid inlet end 101 of the n-th conductive spiral pipe 10 is directly communicated with the liquid return section 3; one connection end 11 is located on the first conductive spiral pipe 10, and the other connection end 11 is located on the n-th conductive spiral pipe 10; in a specific implementation, when the high-voltage equipment is electrically connected with the evaporation spiral pipe section 1, since the connection ends are located on the first two conductive spiral pipes 10, the current can flow through the plurality of series connection pipe type coils formed by the plurality of conductive spiral pipes 10 connected in sequence, and the series connection of the plurality of coils is equivalent to the dispersion arrangement of heat, so that compared with the case of heat concentration in a single large coil, the heat of the plurality of coils is easily dissipated, and local overheating is not easily formed, the heat dissipation area is greatly increased, which is beneficial to the flow of the working medium, so that the overall temperature of the equipment is lower, and the operation is more stable.

[0079] In an embodiment, as Figure 6As shown, in order to improve the evaporation heat dissipation effect of each conductive spiral pipe 10, the plurality of conductive spiral pipes 10 are arranged in parallel, that is, the plurality of conductive spiral pipes 10 are arranged vertically in parallel; the liquid inlet end 101 of the i-th conductive spiral pipe 10 and the liquid inlet end 101 of the i+1-th conductive spiral pipe 10 are communicated with the liquid return section 3 through the first three-way pipe; the steam outlet end 100 of the j-th conductive spiral pipe 10 and the steam outlet end 100 of the j+1-th conductive spiral pipe 10 are communicated with the liquid return section 3 through the second three-way pipe; wherein n≥3; i is an odd number less than n; j is an even number less than n, and in specific implementation, the steam outlet ends 100 of the adjacent two conductive spiral pipes 10 are provided with bypass branches for the outflow of the steam working medium to the liquid return section 3, and the steam of each conductive spiral pipe 10 can flow out in the shortest distance, avoiding the accumulation of steam in the conductive spiral pipe 10 affecting heat dissipation; and the steam flowing out to the liquid return section 3 will be condensed, and the condensed working medium can be quickly supplemented to the conductive spiral pipe 10, avoiding the problem of a small part of the working medium being lacking at the bottom end of the conductive spiral pipe 10 and the working temperature being increased.

[0080] In the present embodiment, in order to reduce the influence of the fluid on the different conductive spiral pipes 10, the first three-way pipe and the second three-way pipe are both Y-shaped three-way pipes, and the inclined pipe section of the Y-shaped three-way pipe, when the fluid of the adjacent two conductive spiral pipes 10 flows upward, the two fluids will not form opposite flows at the joint, but will move in the same direction at the joint, effectively reducing the problem of mutual influence when the fluids of different conductive spiral pipes 10 flow upward, that is, the Y-shaped three-way pipe makes the two fluids more easily flow upward.

[0081] Based on the above embodiment, taking the number of conductive spiral pipes 10 as three as an example, the three conductive spiral pipes 10 are arranged vertically in parallel, the steam outlet end 100 of the leftmost conductive spiral pipe 10 is connected and communicated with the liquid return section 3, the liquid inlet end 101 of the leftmost conductive spiral pipe 10 and the liquid inlet end 101 of the middle conductive spiral pipe 10 are connected and communicated with the liquid return section 3 through the first three-way pipe, the steam outlet end 100 of the middle conductive spiral pipe 10 and the steam outlet end 100 of the rightmost conductive spiral pipe 10 are connected and communicated with the liquid return section 3 through the second three-way pipe, and the liquid inlet end 101 of the rightmost conductive spiral pipe 10 is connected and communicated with the liquid return section 3.

[0082] In another embodiment, a further communication arrangement of the plurality of electrically conductive spiral tubes 10 is further provided, the plurality of electrically conductive spiral tubes 10 are arranged in series along the same axis (not shown); the liquid inlet end 101 of the rth electrically conductive spiral tube 10 is communicated with the vapor-liquid outlet end of the r+1th electrically conductive spiral tube 10 through the third three-way pipe and the liquid return section 3, wherein n≥2; r is a number less than n, that is, the liquid inlet end 101 of each electrically conductive spiral tube 10 can be communicated with the liquid return section 3, so that the liquid return of each electrically conductive spiral tube 10 is smooth. Compared with the parallel arrangement scheme of each electrically conductive spiral tube 10, the series arrangement scheme makes the filled working medium height higher and the steam flow path longer, and the effect is slightly inferior to the parallel arrangement scheme, but it can utilize the vertical space as much as possible and is suitable for scenes with insufficient horizontal space.

[0083] Therefore, the application specifically provides two embodiments of the communication arrangement of the plurality of electrically conductive spiral tubes 10, one is to arrange the plurality of electrically conductive spiral tubes 10 in parallel, and the other is to arrange the plurality of electrically conductive spiral tubes 10 in series on the same straight line. Those skilled in the art can select according to actual needs.

[0084] Embodiment three

[0085] Please refer to Figure 1 The third embodiment of the application provides a manufacturing method of the heat pipe for high-voltage coil, for manufacturing the heat pipe for high-voltage coil of the first or second embodiment, comprising the following steps:

[0086] S1, respectively mounting two wiring ends 11 on two places on the evaporation spiral tube section 1;

[0087] Sealingly assembling the evaporation spiral tube section 1 and each section in sequence to form a heat pipe body with a closed loop;

[0088] S2, vacuumizing the heat pipe body until the first preset vacuum degree is reached in the heat pipe body;

[0089] S3, filling the working medium to be filled into the heat pipe body until the working medium in the heat pipe body reaches a preset height;

[0090] S4, vacuumizing the heat pipe body until the second preset vacuum degree is reached in the heat pipe body, to obtain the heat pipe for high-voltage coil.

[0091] It can be understood that each section includes the condensing section 2 and the insulation section 4; and the first preset vacuum degree and the second preset vacuum degree can be selected according to the relative air pressure range in the heat pipe when the heat pipe works in the three-way pipe; and the preset height can be selected according to the volume of each section of the heat pipe and the working condition of the heat pipe design, so as to ensure that the evaporation spiral pipe section 1 or the insulation section 4 is always filled with the working medium, such as in a specific implementation three-way pipe example, deionized water is used as the working medium to be filled, and the deionized water is filled into the heat pipe body to the height of three-thirds of the three-way pipe two of the storage section.

[0092] In each section, a valve can be arranged, so that each section is connected with a vacuum pump and the valve to perform vacuumizing treatment on the inside of the heat pipe body, and is connected with the valve and a working medium source to fill the working medium into the heat pipe body; after each step of treatment, the valve should be closed before the next step.

[0093] In a specific embodiment, before step S1 is performed, in order to remove impurities in the heat pipe, the working medium to be filled is used to flush the entire heat pipe body.

[0094] Comparative example

[0095] Please refer to Figure 1 The comparative example of the present application provides a heat pipe for high-voltage coil, which is basically the same as example one, except that the comparative example does not have the liquid return section 3.

[0096] The applicant tests example one and the comparative example by using the test power source 5 with a current of 900A and a test duration of 45min; after the above test, the air temperature around the heat pipe of example one is measured to be 27.1°C, and the surface temperature of the heat pipe is measured to be 47.9°C; while after the above test, the air temperature around the heat pipe of the comparative example is measured to be 20.8°C, and the surface temperature of the heat pipe is measured to be 80.3°C; it can be seen that the surface temperature of the heat pipe of the comparative example is much higher than that of example one, which reflects that the heat transfer limit or heat transfer efficiency of the comparative example is far worse than that of example one, and the only difference between the two is whether the liquid return section 3 is provided, so it can be concluded that for the coil type heat pipe, it is important and necessary to provide the liquid return section 3, which can effectively improve the heat transfer limit and cooling efficiency of the heat pipe.

[0097] In addition, the applicant tests example two by using the test power source 5 to gradually increase the current to complete the maximum overload current temperature rise test, measures the maximum overload current of the heat pipe for high-voltage coil, and proves by measurement that the entire high-voltage winding heat pipe has good cooling effect, and the overload capacity is about 140% under the condition that the temperature does not exceed 100°C, which can be put into high-voltage equipment as internal circuit of high-voltage equipment, and has sufficient feasibility.

[0098] The various embodiments described in this specification are presented for the purpose of illustration and description. Each of the embodiments described in this specification is focused on different aspects of the application, and the same or similar parts and principles can be applied to other embodiments.

[0099] The above embodiments are only used to illustrate the technical solutions of the present application, but not limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced by equivalent ones. The modification or replacement does not make the essence of the corresponding technical solution deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

[0100] Finally, it should be noted that the relational terms herein, such as first and second, are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between the entities or operations.

Claims

1. A heat pipe for high-voltage coils, characterized in that, include: A conductive evaporating spiral tube section, wherein the outer wall of the evaporating spiral tube section is provided with two terminals, the two terminals being used to connect to the internal circuit of a high-voltage device; The liquid return section is connected to the evaporation spiral tube section and forms a closed loop. The closed loop is used to allow the working fluid to circulate between the liquid return section and the evaporation spiral tube section. The condensing section is connected to the closed loop and is used to condense the vaporized working fluid evaporated in the evaporating spiral tube section and to allow the condensed liquid working fluid to flow to the return liquid section.

2. The heat pipe for high-voltage coils according to claim 1, characterized in that, The evaporation spiral tube section includes a conductive spiral tube, both ends of which are respectively connected to the return liquid section; On the helical axis of the conductive spiral tube, the two terminals are located at both ends of the conductive spiral tube.

3. The heat pipe for high-voltage coils according to claim 1, characterized in that, The evaporation spiral tube segment includes multiple conductive spiral tubes, which are sequentially and electrically connected. Each of the aforementioned conductive spiral tubes has a steam outlet for supplying vaporized working fluid outflow and a liquid inlet for supplying liquid working fluid inflow; Along the connection sequence of the conductive spiral tubes, multiple conductive spiral tubes are sequentially designated as the first conductive spiral tube, ..., the nth conductive spiral tube; The steam outlet end of the first conductive spiral tube is connected to the liquid return section, and the liquid inlet end of the nth conductive spiral tube is connected to the liquid return section. One of the terminals is located on the first conductive spiral tube, and the other terminal is located on the nth conductive spiral tube.

4. The heat pipe for high-voltage coils according to claim 3, characterized in that: Multiple conductive spiral tubes are arranged in parallel; The liquid inlet end of the i-th conductive spiral tube and the liquid inlet end of the (i+1)-th conductive spiral tube are connected to the return section through a first tee tube. The steam outlet end of the j-th conductive spiral tube and the steam outlet end of the (j+1)-th conductive spiral tube are connected to the return liquid section through a second tee pipe. Where n≥3; i is an odd number less than n; j is an even number less than n.

5. The heat pipe for high-voltage coils according to claim 4, characterized in that, Both the first tee and the second tee are Y-shaped tee pipes.

6. The heat pipe for high-voltage coils according to claim 3, characterized in that: Multiple conductive spiral tubes are arranged in series along the same straight line; The liquid inlet end of the r-th conductive spiral tube and the vapor-liquid outlet end of the (r+1)-th conductive spiral tube are connected to the return liquid section through a third tee tube. Where n≥2; r is a number less than n.

7. The heat pipe for high-voltage coils according to any one of claims 2 to 6, characterized in that, The conductive spiral tube is made of a wound metal tube; Alternatively, the conductive spiral tube may be made by 3D printing of metal material.

8. The heat pipe for high-voltage coils according to claim 1, characterized in that: The return liquid section is an insulated return liquid section; The evaporation spiral tube section is wrapped with an insulating layer. The working fluid inside the heat pipe for the high-voltage coil is a working fluid that has electrical insulation properties when in liquid state.

9. The heat pipe for high-voltage coils according to claim 1, characterized in that, The heat pipe for the high-voltage coil also includes an insulating section. The insulating section connects the evaporating spiral tube section and the condensing section, and the length of the insulating section is greater than the electrical insulation distance of the internal circuit of the high-voltage equipment.

10. A method for manufacturing a heat pipe for a high-voltage coil, characterized in that, The method for manufacturing a heat pipe for a high-voltage coil as described in any one of claims 1 to 9 comprises the following steps: Install the two terminals at two points on the evaporator spiral tube section respectively; The evaporating spiral tube section is sequentially sealed and assembled with each other to form a heat pipe body with a closed loop. The heat pipe body is evacuated until a first preset vacuum level is reached inside the heat pipe body. The working fluid to be filled is introduced into the heat pipe body until the working fluid in the heat pipe body reaches the preset height. The heat pipe body is evacuated until a second preset vacuum level is reached inside the heat pipe body to obtain the heat pipe for the high voltage coil.

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