Converter and oil-immersed converter valve

Abstract

The application relates to the technical field of direct current transmission and discloses a converter and an oil-immersed converter valve, which comprise a diode valve string, a plurality of phase-change radiators, integrated resistors, and a damping capacitor. The diode valve string comprises a plurality of diodes arranged in series. The plurality of phase-change radiators are arranged alternately along the height direction in sequence. The phase-change radiators are used for transferring the heat generated by the diodes into the insulating oil in an oil tank. The plurality of phase-change radiators are arranged in a spiral shape along the height direction, so that a spiral mounting space is formed between adjacent phase-change radiators. The integrated resistors are integrated with a voltage-sharing resistor and a damping resistor. The integrated resistors are arranged in the spiral mounting space. The voltage-sharing resistor is connected in parallel with the diodes. The damping capacitor is in a fan-shaped structure and is arranged along the circumferential direction of the diode valve string. The damping capacitor and the damping resistor constitute a damping loop. The voltage-sharing ring is arranged on the outer circumferential side of the diode valve string and is arranged along the circumferential direction of the diode valve string.

Description

Technical Field

[0001] This invention relates to the field of DC power transmission technology, specifically to converters and oil-immersed converter valves. Background Technology

[0002] With the development of offshore wind power, long-distance power transmission, isolated power supply, and high-capacity DC transmission technologies, high-power converter equipment faces higher requirements in terms of structural compactness, insulation reliability, heat dissipation capacity, and ease of operation and maintenance. Diode converter valves, due to their relatively simple structure, low conduction loss, minimal control requirements, and high reliability, have significant application potential in specific high-voltage, high-power converter scenarios.

[0003] For high-power diode converter valves, the valve string typically consists of multiple diode devices connected in series to meet high voltage requirements. To ensure uniform voltage distribution across the series devices, voltage-equalizing resistors are usually required for the diodes; damping resistors and damping capacitors are also needed to suppress overvoltage and oscillations during the commutation process. Meanwhile, diodes generate a significant amount of heat during operation, requiring efficient heat dissipation structures to dissipate this heat promptly.

[0004] Currently, traditional air-insulated or air-cooled methods face challenges in high-power, high-voltage, and compact applications, including large size, high insulation distance requirements, long heat dissipation paths, and complex external field strength control. Oil-immersed structures can utilize insulating oil to simultaneously perform insulation and cooling functions, offering the potential to improve insulation strength, enhance heat dissipation, and reduce overall size. However, for high-power oil-immersed diode converter valves, especially under conditions of limited internal tank space, the rational arrangement of components such as diodes, phase-change heat sinks, voltage-equalizing resistors, damping resistors, damping capacitors, and voltage-equalizing rings directly affects the valve string volume, oil flow distribution, insulation margin, and operational reliability. If components are arranged in a distributed manner, not only will the tank space utilization be low, but it will also easily form localized sharp points or irregular outer contours, leading to uneven electric field distribution. Summary of the Invention

[0005] In view of this, the present invention provides a converter and an oil-immersed converter valve to solve the problems of low internal space utilization and uneven electric field distribution in the oil tank of oil-immersed diode converter valves.

[0006] In a first aspect, the present invention provides a converter, comprising: A diode valve string, comprising multiple diodes arranged in series; A plurality of phase change heat sinks are provided, and the plurality of phase change heat sinks and the plurality of diodes are arranged alternately along the height direction. The phase change heat sinks are used to transfer the heat generated by the diodes to the insulating oil in the oil tank. The plurality of phase change heat sinks are arranged in a spiral shape along the height direction, so that a spiral installation space is formed between adjacent phase change heat sinks. An integrated resistor includes an integrated voltage equalizing resistor and a damping resistor, wherein the integrated resistor is disposed within the spiral mounting space, and the voltage equalizing resistor is connected in parallel with the diode; The damping capacitor has a fan-shaped structure and is arranged circumferentially along the diode valve string. The damping capacitor and the damping resistor form a damping circuit. A voltage equalizing ring is disposed on the outer periphery of the diode valve string, and the voltage equalizing ring is arranged circumferentially along the diode valve string.

[0007] Beneficial effects: Alternating arrangement of multiple diodes and phase-change heat sinks along the height direction ensures that the heat generated by each diode is quickly and evenly absorbed by the phase-change heat sink. The spiral arrangement of multiple phase-change heat sinks along the height direction creates a regular spiral mounting space between adjacent heat sinks. Embedding an integrated resistor that combines voltage equalization and damping resistors within this spiral mounting space maximizes the utilization of the remaining axial and circumferential space in the valve string. This effectively solves the problems of limited internal space in the oil tank, cluttered component arrangement, and significant space waste, improving the overall integration and space utilization of the converter structure. Arranging multiple phase change heat sinks in a spiral shape along the height direction can also form an orderly insulating oil flow channel inside the oil tank. This can effectively guide the directional flow of insulating oil, accelerate the convection exchange of hot oil on the surface of the phase change heat sink, shorten the heat dissipation path, significantly improve the heat exchange efficiency of the insulating oil, and quickly dissipate the large amount of heat generated by the diode operation. This avoids the problem of heat accumulation and excessive temperature rise of the device under high power conditions, effectively controls the overall operating temperature of the diode valve string, and avoids problems such as device aging, performance degradation, failure and damage caused by high temperature. It is suitable for the high-load continuous operation requirements of large-capacity DC transmission scenarios.

[0008] By setting the damping capacitor as a fan-shaped structure and arranging it around the circumference of the diode valve string, and cooperating with the voltage equalization ring set on the outer periphery of the diode valve string, the voltage equalization ring makes the outermost layer of the diode valve string form a more continuous and smooth electrical boundary. This can improve the electric field distribution on the outside of the valve string, reduce local electric field concentration, reduce the risk of discharge and breakdown under high voltage operation, and ensure the insulation reliability and long-term operational stability of the converter under high power and high voltage conditions.

[0009] Furthermore, integrating the equalizing resistor and damping resistor into a single unit significantly reduces the number of components, connecting lines, and fixing parts compared to separate installations. This simplifies the internal assembly structure of the converter, reduces the probability of loose parts, poor contact, and line faults, and effectively improves the overall mechanical reliability and electrical connection stability of the equipment. At the same time, the integrated layout is more organized and components are more concentrated, greatly reducing the difficulty of equipment assembly, inspection, and maintenance compared to a distributed layout, thus reducing the workload and costs of later operation and maintenance.

[0010] In one optional embodiment, the phase change heat sinks located on both sides of the diode in the height direction have a preset deflection angle in the circumferential direction, thereby arranging the plurality of phase change heat sinks in a spiral shape along the height direction.

[0011] Beneficial effects: By setting a preset deflection angle in the circumferential direction for the phase change heat sinks located on both sides of the diode height direction, multiple phase change heat sinks are arranged in a step-by-step rotating manner along the height direction. This creates circumferentially staggered installation spaces between adjacent phase change heat sinks. The integrated resistor that integrates the voltage equalization resistor and the damping resistor is embedded in this installation space, which maximizes the use of the remaining space in the axial and circumferential directions of the valve string. This effectively solves the problems of small internal space of the oil tank, messy component layout, and serious space waste, and greatly improves the integration and space utilization of the overall converter structure.

[0012] In one alternative embodiment, the phase change heat sink includes a heat-receiving portion pressed against the diode, a phase change cavity for heat transfer, and heat dissipation fins extending into insulating oil, the heat dissipation fins extending outward along the diode valve string in a radial or approximately radial direction.

[0013] Beneficial effects: The heated part is pressed against the diode to receive the heat generated by the diode; a phase change working medium can be set inside the phase change cavity to quickly transfer heat to the heat dissipation area through phase change heat transfer; the heat dissipation fins extend into the insulating oil to increase the contact area with the insulating oil and improve the heat exchange efficiency.

[0014] In one alternative embodiment, the equalizing ring is mounted on the outside of the heat sink fins via a connector.

[0015] Beneficial effects: The equalizing ring creates a more continuous and smooth electrical boundary on the outermost layer of the diode valve string, which helps reduce local field concentration. Since the equalizing ring is mounted on the phase-change heat sink fins, the heat sink itself can be used as a mechanical support foundation, avoiding the need for additional complex support frames, thus further improving integration. Positioning the equalizing ring on the outside of the heat sink fins locks the relative position of the equalizing ring to the diode valve string and surrounding charged components, ensuring circumferential mounting accuracy and coaxiality. This allows the equalizing ring to more accurately and comprehensively cover the high-voltage charged area of ​​the diode valve string, efficiently homogenizing the electric field in the space outside the valve string, suppressing electric field distortion at the tips of irregular structures such as heat sink fins and valve string ends, and further improving the electric field uniformity and insulation margin under high-voltage insulation conditions.

[0016] In one alternative embodiment, the length direction of the integrated resistor is inclined relative to the axis of the diode valve string.

[0017] Beneficial effects: By tilting the integrated resistor along its length relative to the axis of the diode valve string, matching the helical direction of the phase-change heat sink, the integrated resistor extends obliquely along the outer periphery of the valve string. This arrangement allows the integrated resistor to fully utilize the irregular space outside the diode valve string, improving the overall compactness of the converter and reducing its volume. Furthermore, the tilted integrated resistor helps to regulate and streamline the insulating oil flow channels inside the tank, effectively eliminating dead zones and stagnant areas, accelerating the axial and circumferential circulation of the insulating oil within the diode valve string, significantly improving the oil convection heat transfer efficiency, further enhancing the heat dissipation effect of the diodes and phase-change heat sink, and suppressing heat accumulation in devices under high-power conditions.

[0018] In one alternative embodiment, the integrated resistor includes an insulating support, and both the equalizing resistor and the damping resistor are fixed to the insulating support.

[0019] Beneficial effects: Both the equalizing resistor and the damping resistor are fixed on the insulating support, making the integrated resistor an integrated installation module, which facilitates assembly, maintenance and replacement.

[0020] In one optional embodiment, the inner surface of the damping capacitor faces the center of the diode valve string, and the outer surface is an arc surface. After the multiple damping capacitors are arranged circumferentially, the outer surfaces of the multiple damping capacitors are distributed on the same cylindrical surface.

[0021] Beneficial effects: After multiple damping capacitors are arranged circumferentially, their outer surfaces are distributed on the same cylindrical surface, eliminating local sharp edges and protrusions on the overall outer periphery of the converter. This improves space utilization and eliminates the problem of electric field distortion caused by irregular structures at the ends and sides of the damping capacitors. It also ensures a continuous and uniform gradient of the electric field distribution in the circumferential space of the valve string, effectively reducing local field strength concentration. In conjunction with the equalizing ring, it effectively improves the electric field distribution, significantly enhances the overall insulation reliability under high-voltage conditions, and avoids faults such as partial discharge and insulation breakdown.

[0022] In one alternative embodiment, the top of the diode valve string is connected to a mounting structure adapted to connect to the fuel tank cap.

[0023] Beneficial effects: By connecting the mounting structure to the top of the diode valve string, which is suitable for connection with the tank cover, the diode valve string, phase change heat sink, integrated resistor assembly, damping capacitor and equalizing ring can be lifted out of the tank as a whole during operation and maintenance by lifting the tank cover, avoiding personnel from entering the tank and improving maintenance convenience and safety.

[0024] Secondly, the present invention also provides an oil-immersed converter valve, comprising: Fuel tank, including the fuel tank cap; Multiple converters are disposed inside the oil tank, and each of the diode valve strings is connected to a mounting structure at its top, the mounting structure being connected to the oil tank cover.

[0025] Beneficial effects: The tank is filled with insulating oil, which serves as both an insulating and cooling medium, providing insulation protection and heat dissipation for the entire converter valve assembly. The tank includes a tank cover, and each diode valve string has a mounting structure connected to its top. During maintenance, the tank cover can be hoisted to simultaneously remove each converter from the tank, preventing personnel from entering and improving maintenance convenience and safety.

[0026] In one alternative embodiment, the mounting structure is detachably connected to the fuel tank cap.

[0027] Beneficial effects: Since the installation structure is detachably connected to the tank cover, during operation and maintenance, after the tank cover is hoisted, each converter is hoisted out of the tank along with the tank cover. Then the installation structure can be removed from the tank cover, making it easy to remove the converter for maintenance and repair. Attached Figure Description

[0028] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of a converter according to an embodiment of the present invention; Figure 2 A schematic diagram showing the spacing between the diode and the phase change heat sink; Figure 3 This is a schematic diagram of a phase change heat sink arranged spirally along the height direction; Figure 4 A schematic diagram of the installation space formed by the inclined arrangement of integrated resistors in adjacent phase change heat sinks; Figure 5 This is a schematic diagram of a sector-shaped damping capacitor arranged circumferentially. Figure 6 This is a schematic diagram showing the equalizing ring installed on the outside of the photocell heat sink. Figure 7 This is a partial cross-sectional view of a converter at the top according to an embodiment of the present invention; Figure 8 This is a schematic diagram of an oil-immersed converter valve according to an embodiment of the present invention.

[0030] Explanation of reference numerals in the attached figures: 1. Diode valve string; 2. Phase change heat sink; 201. Heated part; 202. Phase change cavity; 203. Heat sink fins; 3. Integrated resistor; 4. Damping capacitor; 5. Equalizing ring; 6. Insulating support; 7. Mounting structure; 8. Oil tank; 801. Oil tank cover. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, 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.

[0032] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0033] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0034] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0035] For high-power oil-immersed diode converter valves, especially under conditions of limited internal space in the oil tank, the rational arrangement of components such as diodes, phase-change heat sinks, voltage-equalizing resistors, damping resistors, damping capacitors, and voltage-equalizing rings directly affects the valve string volume, oil flow distribution, insulation margin, and operational reliability. If the components are arranged in a distributed manner, not only will the oil tank space utilization be low, but it will also easily form local sharp points or irregular outer contours, leading to uneven electric field distribution. Furthermore, if personnel need to enter the oil tank for disassembly and assembly during the operation and maintenance of oil-immersed equipment, it will increase the difficulty of maintenance and safety risks.

[0036] The following is combined Figures 1 to 8 The following describes embodiments of the present invention.

[0037] According to an embodiment of the present invention, in one aspect, a converter is provided, including a diode valve string 1, a phase change heat sink 2, an integrated resistor 3, a damping capacitor 4, and an equalizing ring 5.

[0038] The diode valve string 1 includes multiple diodes connected in series; multiple phase change heat sinks 2 are provided, and the multiple phase change heat sinks 2 and multiple diodes are arranged alternately along the height direction. The phase change heat sinks 2 are used to transfer the heat generated by the diodes to the insulating oil in the oil tank 8. The multiple phase change heat sinks 2 are arranged in a spiral shape along the height direction, so that a spiral installation space is formed between adjacent phase change heat sinks 2; the integrated resistor 3 includes an integrated voltage equalizing resistor and a damping resistor. The integrated resistor 3 is located in the spiral installation space, and the voltage equalizing resistor is connected in parallel with the diode; the damping capacitor 4 has a fan-shaped structure and is arranged along the circumference of the diode valve string 1. The damping capacitor 4 and the damping resistor form a damping circuit; the voltage equalizing ring 5 is located on the outer periphery of the diode valve string 1 and is arranged along the circumference of the diode valve string 1.

[0039] In this embodiment, multiple diodes and multiple phase change heat sinks 2 are arranged alternately along the height direction, ensuring that the heat generated by each diode can be quickly and evenly absorbed by the phase change heat sink 2. Arranging the multiple phase change heat sinks 2 in a spiral shape along the height direction forms a regular spiral mounting space between adjacent phase change heat sinks 2. An integrated resistor 3, which integrates equalizing resistors and damping resistors, is embedded within this spiral mounting space. This maximizes the utilization of the remaining space in the axial and circumferential directions of the valve string, effectively solving the problems of limited internal space, cluttered component arrangement, and significant space waste in the oil tank 8, thereby improving the integration and space utilization of the overall converter structure. Arranging multiple phase change heat sinks 2 in a spiral shape along the height direction can also form an orderly insulating oil flow channel inside the oil tank 8, which can effectively guide the directional flow of insulating oil, accelerate the convection exchange of hot oil on the surface of the phase change heat sink 2, shorten the heat dissipation path, greatly improve the heat exchange efficiency of the insulating oil, and quickly dissipate the large amount of heat generated by the diode operation, avoiding the problem of heat accumulation and excessive temperature rise of the device under high power conditions, effectively controlling the overall operating temperature of the diode valve string 1, avoiding problems such as device aging, performance degradation, failure and damage caused by high temperature, and adapting to the high load continuous operation requirements of large-capacity DC transmission scenarios.

[0040] By setting the damping capacitor 4 as a fan-shaped structure and arranging it around the circumference of the diode valve string 1, and cooperating with the voltage equalization ring 5 set on the outer periphery of the diode valve string 1, the setting of the voltage equalization ring 5 makes the outermost layer of the diode valve string 1 form a more continuous and smooth electrical boundary, which can improve the electric field distribution on the outside of the valve string, reduce the local electric field concentration, reduce the risk of discharge and breakdown under high voltage operation, and ensure the insulation reliability and long-term operation stability of the converter under high power and high voltage conditions.

[0041] Furthermore, integrating the equalizing resistor and damping resistor into a single unit significantly reduces the number of components, connecting lines, and fixing parts compared to separate installations. This simplifies the internal assembly structure of the converter, reduces the probability of loose parts, poor contact, and line faults, and effectively improves the overall mechanical reliability and electrical connection stability of the equipment. At the same time, the integrated layout is more organized and components are more concentrated, greatly reducing the difficulty of equipment assembly, inspection, and maintenance compared to a distributed layout, thus reducing the workload and costs of later operation and maintenance.

[0042] It should be noted that the voltage equalizing resistor is connected in parallel with the diode to achieve voltage equalization; the damping resistor and the damping capacitor 4 form a damping circuit to suppress overvoltage and oscillation during the commutation process.

[0043] In one specific embodiment, multiple diodes are connected in series, and these diodes are press-fitted to multiple phase-change heat sinks 2 at intervals along the height direction of the diode valve string 1. The phase-change heat sinks 2 are disposed between adjacent diodes, or on one or both sides of the diodes. Through the press-fit structure, good thermal contact and electrical connection conditions are formed between the diodes and the phase-change heat sinks 2.

[0044] In one specific embodiment, the gap between adjacent phase change heat sinks 2 is adjustable, which can regulate the flow distribution of oil through the diode valve string 1 inside and outside.

[0045] In one embodiment, such as Figure 2 and Figure 3 As shown, the phase change heat sinks 2 located on both sides of the diode in the height direction have a preset deflection angle in the circumferential direction, so that multiple phase change heat sinks 2 are arranged in a spiral shape along the height direction.

[0046] In this embodiment, by setting a preset deflection angle in the circumferential direction for the phase change heat sinks 2 located on both sides of the diode height direction, multiple phase change heat sinks 2 are arranged in a progressively rotating manner along the height direction, forming a circumferentially staggered installation space between adjacent phase change heat sinks 2. The integrated resistor 3, which integrates the equalizing resistor and the damping resistor, is embedded in this installation space, which maximizes the use of the remaining space in the axial and circumferential directions of the valve string. This effectively solves the problems of small internal space, messy component arrangement, and serious space waste in the oil tank 8, and greatly improves the integration and space utilization of the overall converter structure.

[0047] With the aforementioned spiral arrangement, the phase change heat sinks 2 no longer completely overlap in the height direction, but are staggered step by step in the circumferential direction. This structure can create oblique installation space between adjacent phase change heat sinks 2, and allow the insulating oil to obtain a combined circumferential and axial flow path inside the diode valve string 1. Compared with a simple vertical stacking structure, this arrangement is more conducive to reducing local oil flow dead zones and improving the overall heat transfer uniformity of the oil-immersed diode valve.

[0048] It should be noted that the preset deflection angle can be determined based on the diameter of the diode valve string 1, the number of diodes, the length of the heat sink fins, the size of the integrated resistor 3, the size of the damping capacitor 4, and the requirements for oil flow organization.

[0049] In one embodiment, such as Figure 3 As shown, the phase change heat sink 2 includes a heat-receiving part 201 that is pressed against the diode, a phase change cavity 202 for heat transfer, and heat dissipation fins 203 that extend into the insulating oil. The heat dissipation fins 203 extend outward along the radial or approximately radial direction of the diode valve string 1.

[0050] In this embodiment, the heated part 201 is pressed against the diode to receive the heat generated by the diode; the phase change cavity 202 may be equipped with a phase change working medium to quickly transfer heat to the heat dissipation area through phase change heat transfer; the heat dissipation fins 203 extend into the insulating oil to increase the contact area with the insulating oil and improve the heat exchange efficiency.

[0051] In one embodiment, the equalizing ring 5 is mounted on the outside of the heat sink fin 203 via a connector.

[0052] In this embodiment, the equalizing ring 5 creates a more continuous and smooth electrical boundary on the outermost layer of the diode valve string 1, which helps reduce local field concentration. Since the equalizing ring 5 is mounted on the fins of the phase change heat sink 2, the heat sink itself can be used as a mechanical support base, avoiding the need for additional complex support frames, thereby further improving integration. Positioning the equalizing ring 5 on the outside of the heat sink fins 203 locks the relative position of the equalizing ring 5 with the diode valve string 1 and the outer peripheral charged components, ensuring the circumferential installation accuracy and coaxiality of the equalizing ring 5. This allows the equalizing ring 5 to more accurately and comprehensively cover the high-voltage charged area of ​​the diode valve string 1, efficiently homogenize the electric field in the space outside the valve string, suppress the electric field distortion at the tips of irregular structures such as the heat sink fins 203 and the valve string ends, and further improve the electric field uniformity and insulation margin under high-voltage insulation conditions.

[0053] In an alternative embodiment, the equalizing ring 5 is mounted on a support structure that is fixedly connected to the radiator fins.

[0054] Specifically, the equalizing ring 5 extends circumferentially along the diode valve string 1 and can be configured as a complete ring structure, such as... Figure 6 As shown, it can also be formed by splicing multiple arc-shaped segments. When the equalizing ring 5 is formed by splicing multiple arc-shaped segments, the multiple arc-shaped segments can be arranged in a spiral shape. The equalizing ring 5 can be provided with through holes for insulating oil to pass through, so as to facilitate the entry of insulating oil into the converter.

[0055] In one embodiment, such as Figure 4 As shown, the length direction of the integrated resistor 3 is inclined relative to the axis of the diode valve string 1.

[0056] In this embodiment, the integrated resistor 3 is tilted relative to the axis of the diode valve string 1, with its tilt direction matching the spiral direction of the phase change heat sink 2, allowing the integrated resistor 3 to extend obliquely along the outer periphery of the valve string. This arrangement allows the integrated resistor 3 to fully utilize the irregular space outside the diode valve string 1, improving the overall compactness of the converter and reducing its volume. Furthermore, the tilted integrated resistor 3 can regulate and streamline the insulating oil flow channels inside the oil tank 8, effectively eliminating localized dead zones and stagnant areas, accelerating the axial and circumferential circulation of the insulating oil in the diode valve string 1, significantly improving the oil convection heat transfer efficiency, further enhancing the heat dissipation effect of the diode and the phase change heat sink 2, and suppressing heat accumulation problems in devices under high-power conditions.

[0057] In one embodiment, the integrated resistor 3 includes an insulating support, and both the equalizing resistor and the damping resistor are fixed on the insulating support.

[0058] In this embodiment, both the equalizing resistor and the damping resistor are fixed on the insulating support, making the integrated resistor 3 an integrated mounting module, which facilitates assembly, maintenance and replacement.

[0059] In one specific embodiment, the insulating support may include an inner insulating tube and an outer insulating tube, which are connected by an end connection structure. An equalizing resistor is disposed on the outer surface of the inner insulating tube, and a damping resistor is disposed on the outer surface of the outer insulating tube. A gap is formed between the outer insulating tube and the damping resistor. The outer insulating tube is provided with an oil passage hole that penetrates the tube wall of the outer insulating tube and communicates with the gap. The damping resistor and the equalizing resistor can be connected to the corresponding circuit through the end connection structure.

[0060] In one embodiment, such as Figure 5 As shown, the inner surface of the damping capacitor 4 faces the center of the diode valve string 1, and the outer surface is an arc surface. After multiple damping capacitors 4 are arranged circumferentially, the outer surfaces of the multiple damping capacitors 4 are distributed on the same cylindrical surface.

[0061] In this embodiment, after multiple damping capacitors 4 are arranged circumferentially, the outer surfaces of the multiple damping capacitors 4 are distributed on the same cylindrical surface, so that there are no local sharp corners or protruding structures on the outer periphery of the converter. Under the premise of improving space utilization, the problem of electric field tip distortion caused by the irregular structure at the end and side of the damping capacitors 4 is eliminated from the source. This makes the gradient of the electric field distribution in the circumferential space of the valve string continuous and uniform, effectively reducing the phenomenon of local field strength concentration. In conjunction with the equalizing ring 5, it effectively improves the electric field distribution, greatly improves the overall insulation reliability under high voltage conditions, and avoids faults such as partial discharge and insulation breakdown.

[0062] Specifically, the traditional damping capacitor 4 has a rectangular structure. When the rectangular damping capacitor 4 is arranged outside the valve string, it is easy to form abrupt changes in the outer contour and local sharp corner areas, which is not conducive to the uniform distribution of the electric field inside the oil tank 8. In this embodiment, by using a fan-shaped damping capacitor 4, the shape of the damping capacitor 4 matches the cylindrical contour of the valve string, thereby improving space utilization and improving the external electric field distribution.

[0063] In this embodiment, the diode, phase change heat sink 2, integrated resistor 3 assembly, fan-shaped damping capacitor 4 and equalizing ring 5 together form a cylindrical or near-cylindrical converter assembly. This structure is beneficial for forming a regular outer boundary inside the oil tank 8, so that a relatively uniform annular oil flow channel and insulation gap are formed between the converter and the inner wall of the oil tank 8.

[0064] In one embodiment, a mounting structure 7 is connected to the top of the diode valve string 1, and the mounting structure 7 is adapted to be connected to the oil tank cover 801.

[0065] In this embodiment, by connecting the mounting structure 7 to the top of the diode valve string 1, and the mounting structure 7 being adapted to be connected to the tank cover 801, during operation and maintenance, the diode valve string 1, phase change heat sink 2, integrated resistor 3 assembly, damping capacitor 4 and equalizing ring 5 can be hoisted out of the tank 8 as a whole by hoisting the tank cover 801, avoiding personnel from entering the tank 8 and improving maintenance convenience and safety.

[0066] Specifically in one embodiment, such as Figure 7 As shown, the top of the diode valve string 1 is connected to the mounting structure 7 via an insulating support 6. The insulating support 6 can maintain electrical insulation between the diode valve string 1 and the oil tank cover 801, and the insulating support 6 can also provide mechanical support for the diode valve string 1.

[0067] More specifically, mounting structure 7 can be a flange.

[0068] According to an embodiment of the present invention, another aspect provides an oil-immersed converter valve, including an oil tank 8 and a plurality of converters provided in the above embodiments.

[0069] Among them, such as Figure 8 As shown, the oil tank 8 includes an oil tank cover 801; multiple converters are located inside the oil tank 8, and each diode valve string 1 has a mounting structure 7 connected to its top, which is connected to the oil tank cover 801.

[0070] In this embodiment, the oil tank 8 is filled with insulating oil, which serves as both an insulating and cooling medium, providing insulation protection and heat dissipation for the entire converter valve. The oil tank 8 includes an oil tank cover 801, and each diode valve string 1 has a mounting structure 7 connected to its top. The mounting structure 7 is connected to the oil tank cover 801. During operation and maintenance, each converter can be simultaneously lifted out of the oil tank 8 by hoisting the oil tank cover 801, preventing personnel from entering the interior of the oil tank 8 and improving maintenance convenience and safety.

[0071] Specifically, the top of each diode valve string 1 is connected to the mounting structure 7 via an insulating support 6, and the mounting structure 7 is a flange.

[0072] Specifically, the oil tank 8 can be connected to an external cooling system so that the insulating oil, after absorbing heat, can be cooled by the external cooling device and then re-enter the oil tank 8.

[0073] In one embodiment, the mounting structure 7 is detachably connected to the fuel tank cover 801.

[0074] In this embodiment, since the mounting structure 7 is detachably connected to the tank cover 801, during operation and maintenance, after the tank cover 801 is hoisted, each converter is hoisted out of the tank 8 along with the tank cover 801. Then the mounting structure 7 can be removed from the tank cover 801, making it easy to remove the converter for maintenance and repair.

[0075] The converter and oil-immersed converter valve provided in this embodiment have the following technical advantages: First, by press-fitting the diode and the phase change heat sink 2 together at an interval, the heat generated by the diode can be quickly transferred into the insulating oil through the phase change heat sink 2, which shortens the heat dissipation path and improves the heat dissipation efficiency of the oil-immersed diode valve.

[0076] Second, the phase change heat sink 2 is arranged spirally along the height direction to form a continuous spatial structure inside the converter with a flow guiding effect, which is conducive to the flow of insulating oil inside the converter and improves heat exchange efficiency.

[0077] Third, by utilizing the space created by the spiral arrangement of the phase change heat sink 2, the integrated resistor 3, which consists of the equalizing resistor and the damping resistor, is installed at an angle, so that the integrated resistor 3 can be embedded in the inclined space inside the converter, thereby improving space utilization and reducing the overall size of the converter.

[0078] Fourth, the damping capacitor 4 is designed as a fan-shaped structure with an arc-shaped outer surface, which can match the overall cylindrical outline of the converter and avoid the abrupt change in shape caused by traditional rectangular or block-shaped capacitors.

[0079] Fifth, an equalizing ring 5 is set on the outermost layer and installed on the radiator fins, so that the converter as a whole forms a cylindrical or near-cylindrical structure, which is beneficial to improve the electric field distribution in the oil tank 8, reduce local electric field concentration, and improve insulation reliability.

[0080] Sixth, the upper part of the diode valve string 1 is connected to the oil tank cover 801 through the insulating support 6 and the mounting flange, so that the converter can be lifted out of the oil tank 8 as a whole along with the oil tank cover 801. During operation and maintenance, no personnel need to enter the oil tank 8, which improves the convenience and safety of maintenance.

[0081] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by this application.

Claims

1. A converter, characterized in that, include: A diode valve string (1) includes multiple diodes arranged in series; A plurality of phase change heat sinks (2) are provided. The plurality of phase change heat sinks (2) and the plurality of diodes are arranged alternately along the height direction. The phase change heat sinks (2) are used to transfer the heat generated by the diodes to the insulating oil in the oil tank (8). The plurality of phase change heat sinks (2) are arranged in a spiral shape along the height direction, so that a spiral installation space is formed between adjacent phase change heat sinks (2). The integrated resistor (3) includes an integrated voltage equalizing resistor and a damping resistor. The integrated resistor (3) is disposed in the spiral mounting space. The voltage equalizing resistor is connected in parallel with the diode. The damping capacitor (4) has a fan-shaped structure and is arranged along the circumference of the diode valve string (1). The damping capacitor (4) and the damping resistor form a damping circuit. A voltage equalization ring (5) is disposed on the outer periphery of the diode valve string (1), and the voltage equalization ring (5) is arranged circumferentially along the diode valve string (1).

2. The converter according to claim 1, characterized in that, The phase change heat sinks (2) located on both sides of the diode in the height direction have a preset deflection angle in the circumferential direction, so that the multiple phase change heat sinks (2) are arranged in a spiral shape along the height direction.

3. The converter according to claim 1, characterized in that, The phase change heat sink (2) includes a heat-receiving part (201) pressed against the diode, a phase change cavity (202) for heat transfer, and heat dissipation fins (203) extending into the insulating oil. The heat dissipation fins (203) extend outward along the radial or approximately radial direction of the diode valve string (1).

4. The converter according to claim 3, characterized in that, The equalizing ring (5) is installed on the outside of the heat dissipation fins (203) via a connector.

5. The converter according to any one of claims 1 to 4, characterized in that, The length direction of the integrated resistor (3) is inclined relative to the axis of the diode valve string (1).

6. The converter according to any one of claims 1 to 4, characterized in that, The integrated resistor (3) includes an insulating support, and the equalizing resistor and the damping resistor are both fixed on the insulating support.

7. The converter according to any one of claims 1 to 4, characterized in that, The inner surface of the damping capacitor (4) faces the center of the diode valve string (1), and the outer surface is an arc surface. After the multiple damping capacitors (4) are arranged circumferentially, the outer surfaces of the multiple damping capacitors (4) are distributed on the same cylindrical surface.

8. The converter according to any one of claims 1 to 4, characterized in that, The top of the diode valve string (1) is connected to a mounting structure (7), which is adapted to be connected to the fuel tank cover (801).

9. An oil-immersed converter valve, characterized in that, include: Fuel tank (8), including fuel tank cover (801); The converter according to any one of claims 1 to 8 is disposed in the oil tank (8), and each of the diode valve strings (1) is connected to a mounting structure (7) at the top, the mounting structure (7) being connected to the oil tank cover (801).

10. The oil-immersed converter valve according to claim 9, characterized in that, The mounting structure (7) is detachably connected to the fuel tank cover (801).

Images