WO2023045055A1 - 一种800kV柔性直流穿墙套管 - Google Patents

一种800kV柔性直流穿墙套管 Download PDF

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Publication number
WO2023045055A1
WO2023045055A1 PCT/CN2021/131759 CN2021131759W WO2023045055A1 WO 2023045055 A1 WO2023045055 A1 WO 2023045055A1 CN 2021131759 W CN2021131759 W CN 2021131759W WO 2023045055 A1 WO2023045055 A1 WO 2023045055A1
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WO
WIPO (PCT)
Prior art keywords
current
carrying
spring
outdoor
indoor
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Application number
PCT/CN2021/131759
Other languages
English (en)
French (fr)
Inventor
高锡明
夏谷林
冯鸫
贺志
陈欢
吕金壮
蔡希鹏
张晋寅
韦晓星
潘志城
邓军
谢志成
张良
李士杰
王剑坤
彭翔
吴瀛
杨旭
周海滨
刘青松
Original Assignee
中国南方电网有限责任公司超高压输电公司检修试验中心
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Publication of WO2023045055A1 publication Critical patent/WO2023045055A1/zh

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
    • H02G3/00—Installations of electric cables or lines or protective tubing therefor in or on buildings, equivalent structures or vehicles
    • H02G3/22—Installations of cables or lines through walls, floors or ceilings, e.g. into buildings
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B17/00—Insulators or insulating bodies characterised by their form
    • H01B17/56—Insulating bodies
    • H01B17/58—Tubes, sleeves, beads, or bobbins through which the conductor passes
    • H01B17/583—Grommets; Bushings
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]

Definitions

  • the invention relates to flexible DC transmission power equipment, in particular to an 800kV flexible DC wall bushing.
  • the flexible DC wall bushing is the core equipment of the flexible DC transmission project.
  • the flexible DC wall bushing is installed on the wall of the valve hall to establish electrical connections between the valve tower equipment in the valve hall and the DC field smoothing reactor and other equipment.
  • flexible DC wall bushings have more stringent operating conditions. Under the complex working conditions of AC and DC voltage superimposition, the heat and vibration of the bushing are more intense, which affects the sealing performance and current-carrying structure of the bushing. And grounding performance put forward higher requirements.
  • the flexible straight bushing Based on the working condition of the flexible straight bridge arm side, in terms of current-carrying design, the flexible straight bushing carries the AC-DC compound current on the bridge arm side of the system, and the overall temperature distribution of the bushing is different from that of the pure DC bushing: (1) Considering the skin effect, the AC When the current component passes through the current-carrying conductor of the bushing, the current is concentrated on the surface of the conductor, and the closer to the surface of the conductor, the greater the current density, resulting in increased conductor loss and temperature rise. (2) Under the action of the magnetic field generated by the alternating current, eddy currents are generated inside metal parts such as bushing coiled pipes, which will also affect the distribution of the thermal field. Therefore, it is necessary to consider the above factors in the current-carrying design of the bushing;
  • insulation structure design (1) The DC voltage of the flexible straight side bridge arm contains high-frequency harmonic components above 50Hz, and the insulation design of the capacitor plate under DC and high-frequency harmonics needs to be considered; (2) Special thermal field distribution To affect the resistivity and dielectric constant distribution of the bushing insulation material, it is necessary to consider the electrode layout to reasonably distribute the electric field of the voltage of each layer of insulating medium at different temperatures under DC and high-frequency harmonics, and the effect of a uniform electric field has been achieved.
  • the total length of the bushing exceeds 20m, and the two ends of the horizontally installed DC through-wall bushing are subjected to bending moments.
  • the overall current-carrying structure of the bushing is under the action of thermal expansion and contraction. It is also necessary to maintain the cooperation with other parts to ensure the overall sealing performance.
  • the sealing structure of the existing conventional DC wall bushing structure is poor, and the defects and frequent faults of the bushing occur air leakage; the existing DC wall bushings in operation have many electrical failures caused by improper insulation design; at the same time, the DC wall bushing
  • the design defect of the current-carrying structure of the wall bushing will lead to the overheating defect of the bushing during operation; the above problems seriously affect the stable operation of the DC wall bushing and the DC transmission project.
  • the configuration of the existing DC wall bushing especially the size configuration of the multilayer capacitive screen of the capacitor core and the radial and axial dimensions of the multilayer capacitive screen, will affect the electric field strength of the first screen and the last screen. Influenced, the probability of insulation breakdown of the capacitor core is higher.
  • the present invention provides a flexible DC wall bushing, which is suitable for the operating condition of the flexible DC bridge arm side, and solves the uneven distribution of the electric field of the conventional DC wall bushing in the past, and the capacitor core is prone to insulation breakdown problem.
  • the technical scheme that the present invention takes is:
  • An 800kV flexible DC wall bushing including a sleeve and a capacitor core arranged in the sleeve, the 800kV flexible DC wall bushing also includes a first flange, an outdoor composite insulator, and an indoor composite insulator , current-carrying conductors and aluminum coiled tubes;
  • the first flange is arranged on the sleeve, and the first flange divides the sleeve into an outdoor section and an indoor section; the outdoor composite insulator and the indoor composite insulator pass through the first The flanges are respectively fixedly sleeved on the outdoor section and the indoor section of the sleeve;
  • the current-carrying conductor passes through the aluminum coiled tube and is arranged coaxially and spaced apart from the aluminum coiled tube, the current-carrying conductor has an outdoor end and an indoor end, and the outdoor end of the current-carrying conductor and the indoor end pass through the aluminum coiled pipe and pass through the first end of the outdoor section of the sleeve away from the first flange and the indoor section of the sleeve away from the first flange respectively. the second end of the flange; both ends of the aluminum coiled tube are connected to the current-carrying conductor;
  • the capacitor core includes multi-layer glue-impregnated paper and multi-layer capacitive screen, and the multi-layer glue-impregnated paper and multi-layer capacitive screen are alternately wound on the aluminum coiled tube;
  • the multi-layer capacitive screen includes The first capacitive screen, the middle capacitive screen and the last capacitive screen radially from the inside to the outside, wherein, the axial length ratio of the middle capacitive screen to the last capacitive screen, and, the middle capacitive screen to the last capacitive screen
  • the difference of twice the radial thickness ratio between the last capacitive screens is a preset threshold.
  • the present invention adopts the double-conduit current-carrying structure of the current-carrying conductor and the aluminum coiled tube, and the aluminum coiled tube undertakes the coiling and mechanical bearing of the capacitor core, and the current-carrying conductor serves as the bearing of high voltage and current, thereby reducing the number of sleeves.
  • the internal heating of the tube avoids the influence of the current-carrying heat of the current-carrying conductor on the insulation performance of the capacitor core; in addition, by adjusting the axial length of the middle capacitive screen and the last capacitive screen and the middle capacitive screen and the last capacitive screen Optimal design of the radial thickness of the insulating layer between them effectively reduces the electric field intensity of the first screen and the last screen, and optimizes the axial and radial electric field intensity distribution of the capacitor core to prevent the local electric field from increasing and causing the capacitor core to insulate Breakdown greatly reduces the probability of insulation breakdown of the capacitor core.
  • the range of the preset threshold is 0cm-2cm.
  • the 800kV flexible DC wall bushing also includes an outdoor end structure and an indoor end structure, the outdoor end structure is arranged at the first end of the sleeve, and the indoor end structure Structures are provided at the second end of the sleeve to provide a connection between the outdoor end of the current-carrying conductor and the first end of the sleeve, and the indoor end of the current-carrying conductor and the The second end of the sleeve is sealed.
  • the indoor end structure includes a first end cover plate, a spring compression structure, a first general cap and a first top cover;
  • the spring compression structure includes a cylindrical spring seat, a spring pressing plate and several spring components;
  • the upper end of the spring seat has a first outer flange extending outward, and the lower end of the spring seat has a second inner flange extending inward.
  • the second inner flange is provided with a number of the first opening of the distribution;
  • the spring pressing plate has a circular shape and is matched in a cylindrical spring seat, and the spring pressing plate is provided with a first opening through which the current-carrying guide rod passes and a matching opening for the first opening. a plurality of second openings;
  • Each of the spring assemblies includes a spring guide rod, a guide rod nut, a spring, a spring pressure head and a centering nut; each of the springs is arranged between the second inner flange of the spring seat and the spring pressure plate , each of the spring guide rods passes through the guide rod nut, the first opening of the spring pressure plate, the spring pressure head, the spring, the centering nut and the second opening in turn, to fix the spring between the second inner flange of the spring seat and the spring pressure plate;
  • the first end cover is provided with a second opening for the current-carrying guide rod to pass through and a groove for the first outer flange of the spring seat to be installed, and the first end cover is sealingly arranged on the on the second end of the sleeve;
  • the first general cap is provided with a first inner chamber adapted to the indoor end of the current-carrying guide rod and a third outer flange arranged on the outer peripheral surface of the first inner chamber;
  • the first top cover is provided with a third opening through which the current-carrying guide rod passes, and the first top cover is provided between the third outer flange of the first general cap and the first end cover plate Between, to realize the sealing between the first general cap and the first end cover plate and the spring seat;
  • the indoor end of the current-carrying guide rod passes through the lower end of the spring seat, the first opening of the spring pressure plate, the upper end of the spring seat, and the second opening of the first end cover in sequence.
  • the third opening of the first top cover is located in the first inner chamber of the first general cap.
  • the indoor end structure also includes a pressure bearing plate and a first current-carrying unit
  • the pressure bearing plate is located above the spring pressure plate and is sleeved on the current-carrying guide rod; the first current-carrying unit is arranged on the inner circumferential surface of the first inner cavity of the first general cap and the between the current-carrying guide rods; the first current-carrying unit includes a first upper limit collar, a first lower limit collar, and a first upper limit collar and a first lower limit collar between the first strap fingers.
  • the spring By setting the pressure bearing plate socketed with the current-carrying guide rod above the spring pressure plate, during operation, when the pressure bearing plate applies downward compression force to the spring below the spring pressure plate, the spring is then Give the pressure bearing plate an upward axial thrust, and the pressure bearing plate and the current-carrying guide rod are in a connected relationship, so that the current-carrying guide rod is subjected to the upward axial thrust of the spring, suppressing the change of the disturbance of the current-carrying guide rod, thereby ensuring It ensures the uniformity of the contact between the current-carrying guide rod and the watchband finger of the indoor end structure, ensures the reliability of the current-carrying, and avoids the occurrence of failures.
  • the indoor end structure also includes an indoor end flange, an indoor end pressure equalizing device and several sealing rings;
  • the indoor end flange is sleeved on the outer periphery of the second end of the sleeve and is detachably and fixedly connected with the first end cover to fix the first end cover on the sleeve. on the second end of the barrel;
  • the indoor end pressure equalizing device is located between the spring compression structure and the sleeve;
  • the plurality of sealing rings include a first flat sealing ring, a second flat sealing ring, a third flat sealing ring, a fourth flat sealing ring and a first axial sealing ring;
  • the first flat sealing ring is arranged between the first general cap and the first top cover, and the second flat sealing ring is arranged between the first top cover and the first end cover plate , the third flat sealing ring is arranged at the connection between the first end cover plate and the spring seat of the spring compression structure, and the fourth flat sealing ring is arranged between the indoor end flange and the Between the first end cover plates, the first axial sealing ring is arranged between the current-carrying conductor and the first top cover.
  • the first end cover plate is fixed on the second end of the sleeve, and the setting of the pressure equalizing device at the indoor end ensures the uniformity of the electric field distribution at the indoor end. Uniformity; and the setting of the sealing ring further ensures the sealing between the indoor end structure and the sleeve.
  • the outdoor end structure includes a second end cover plate, a second general cap, a second top cover and a second current-carrying structure;
  • the second end cover plate is provided with a fourth opening through which the current-carrying guide rod passes;
  • the second general cap is provided with a second inner chamber adapted to the outdoor end of the current-carrying guide rod and a fourth outer flange arranged on the outer peripheral surface of the second inner chamber;
  • the second top cover is provided with a fifth opening through which the current-carrying guide rod passes, and the second top cover is arranged between the fourth outer flange of the second general cap and the second end cover plate. Between, to realize the sealing between the second general cap and the second end cover;
  • the outdoor end of the current-carrying guide rod passes through the fourth opening of the second end cover plate, the fifth opening of the second end cover plate in turn, and is located in the second inner cavity of the second general cap.
  • the outdoor end structure also includes a second current-carrying unit, and the second current-carrying unit is arranged between the inner circumferential surface of the second inner cavity of the second general cap and the current-carrying guide rod
  • the second current-carrying unit includes a second upper limit collar, a second lower limit collar, and a second wristband contact finger arranged between the second upper limit collar and the second lower limit collar.
  • the current-carrying guide rod is connected to the potential of the second general cap through the contact fingers of the strap, and insulating limit collars are set on both sides of the strap to avoid the mechanical gravity of the wall bushing caused by its own mechanical gravity during the actual assembly and operation. Local overheating and discharge faults caused by the misalignment between the current-carrying guide rod and the end seal structure.
  • the outdoor end structure also includes an outdoor end flange, an outdoor end pressure equalizing device, a fifth flat sealing ring, a sixth flat sealing ring, a seventh flat sealing ring and a second axial sealing ring;
  • the outdoor end flange is sleeved on the outer periphery of the first end of the sleeve and is detachably and fixedly connected to the second end cover to fix the second end cover on the sleeve on the first end of the
  • the outdoor end pressure equalizing device is located between the current-carrying guide rod and the sleeve;
  • the fifth flat sealing ring is arranged between the second general cap and the second end cover, and the sixth flat sealing ring is arranged between the second top cover and the second end cover Between, the seventh flat sealing ring is arranged between the outdoor end flange of the bushing and the second end cover plate; the second axial sealing ring is arranged between the current-carrying conductor and the Between the second top cover.
  • the 800kV flexible DC wall bushing includes a first conductive part and a first insulating part, one end of the aluminum coiled pipe is equipotentially connected to the current-carrying conductor through the first conductive part, and the The other end of the aluminum coiled tube is insulated and connected to the current-carrying conductor through the first insulating member, and an insulating medium is arranged between the aluminum coiled tube and the current-carrying conductor.
  • the gap between the current-carrying conductor and the aluminum coiled tube is avoided.
  • the formation of circulating current affects the performance of the wall bushing; and an insulating medium is set between the aluminum coiled tube and the current-carrying conductor to insulate and support the current-carrying conductor and the aluminum tube to ensure that the current-carrying conductor Concentricity with aluminum tube.
  • the first conductive member is a canted coil spring.
  • the 800kV flexible DC wall bushing also includes a first equalizing device and a second equalizing device, the first equalizing device and the second equalizing device are respectively arranged on the aluminum coiled pipe two connections to the current-carrying conductors.
  • the 800kV flexible DC wall bushing also includes a first equalizing ring and a second equalizing ring, the first equalizing ring is arranged at the first end of the sleeve, and the second equalizing ring A pressure ring is disposed at the second end of the sleeve.
  • the outdoor section and the indoor section of the sleeve have an asymmetric structure, and the length of the capacitor core located in the outdoor section is longer than the length of the capacitor core located in the indoor section.
  • Fig. 1 is the structural representation of the 800kV flexible DC wall bushing of the embodiment of the present invention.
  • Fig. 2 is a schematic structural view of the last screen extraction device according to the embodiment of the present invention.
  • Fig. 3 is a structural schematic diagram of the middle structure of the sleeve of the embodiment of the present invention.
  • Fig. 4 is a structural schematic diagram of an indoor end structure of an embodiment of the present invention.
  • Fig. 5 is a structural schematic diagram of another usage form of the indoor end structure of the embodiment of the present invention.
  • Fig. 6 is a schematic structural view of a spring compression device according to an embodiment of the present invention, wherein Fig. 6 (a) is a schematic structural view of a spring compression structure, and Fig. 6 (b) is a structural schematic view of a head equipped with a spring compression structure;
  • FIG. 7 is a schematic structural view of an outdoor end structure according to an embodiment of the present invention.
  • Fig. 8 is a design schematic diagram of the casing sealing structure of the embodiment of the present invention. wherein, Fig. 8 (a) is the sealing structure of the indoor end; Fig. 8 (b) is the sealing structure of the outdoor end; Fig. 8 (c) is the sealing structure of the middle part ;
  • FIG. 9 is a schematic diagram of a dual conduit current-carrying structure according to an embodiment of the present invention.
  • Fig. 10 is a schematic diagram of the current-carrying structure of the indoor end structure and the outdoor end structure;
  • FIG. 11 is a schematic structural diagram of a capacitor core.
  • the first general cap 32.
  • the first current-carrying structure 34.
  • the first flat sealing ring 35.
  • plural means at least two, such as two, three, etc., unless otherwise specifically defined.
  • the terms “mounted”, “connected” and “connected” should be interpreted in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical
  • a connection can also be an electrical connection; it can be a direct connection or an indirect connection through an intermediary, and it can be the internal communication of two components.
  • the first feature may be in direct contact with the first feature or the first and second feature may be in direct contact with the second feature through an intermediary. touch.
  • “above”, “above” and “above” the first feature on the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature.
  • “Below”, “beneath” and “beneath” the first feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is less horizontally than the second feature.
  • the present invention provides an 800kV flexible DC wall bushing to solve the problem that the electric field distribution of the conventional DC wall bushing is uneven and the capacitor core is prone to insulation breakdown.
  • the 800kV flexible DC wall bushing also includes a first flange 6, an outdoor composite insulator 4, an indoor composite insulator 5, a current-carrying conductor 2 and Aluminum coiled pipe 3; the first flange 6 is arranged on the sleeve, and the first flange 6 divides the sleeve into an outdoor section and an indoor section; the outdoor composite insulator 4 and the indoor composite insulator 5 pass through the first flange 6 respectively
  • the fixed sleeve is set on the outdoor section and the indoor section of the sleeve;
  • the current-carrying conductor 2 passes through the aluminum coiled tube 3 and is coaxially arranged with the aluminum coiled tube 3.
  • the current-carrying conductor 2 has an outdoor end and an indoor end, and the outdoor end and the indoor end of the current-carrying conductor 2 are Pass through the aluminum coiled tube 3 and pass through the first end of the outdoor section of the sleeve away from the first flange 6 and the second end of the indoor section of the sleeve away from the first flange 6 respectively; the aluminum coiled tube Both ends of 3 are connected with current-carrying conductor 2;
  • the capacitor core 1 includes multi-layer glue-impregnated paper and multi-layer capacitive screen, and the multi-layer glue-impregnated paper and multi-layer capacitive screen are alternately wound on the aluminum coiled tube 3;
  • the multi-layer capacitive screen includes The first layer capacitive screen 81-1, the middle capacitive screen 81-2 and the last layer capacitive screen 81-3, wherein, the ratio of the axial length of the middle capacitive screen 81-2 to the last layer capacitive screen 81-3, and, the middle capacitance
  • the difference of twice the radial thickness ratio between the screen 81-2 and the last capacitive screen 81-3 is a preset threshold.
  • the invention enables electrical insulation and mechanical support of the current-carrying conductor 2 .
  • the range of the preset threshold is 0cm-2cm;
  • the current-carrying conductor 2 is a copper rod current-carrying conductor 2 .
  • the outdoor section and the indoor section of the sleeve have an asymmetric structure, and the length of the capacitor core 1 located in the outdoor section is longer than that of the capacitor core 1 located in the indoor section.
  • the present invention adopts the double-conduit current-carrying structure of the current-carrying conductor 2 and the aluminum coiled tube 3, and the aluminum coiled tube 3 undertakes the coiling and mechanical bearing of the capacitor core 1, and the current-carrying conductor 2 serves as a high voltage and current bearing , thereby reducing the internal heating of the bushing, and avoiding the influence of the insulation performance of the capacitor core 1 due to the current-carrying heat of the current-carrying conductor 2 .
  • the current-carrying conductor 2 is arranged coaxially with the aluminum coiled tube 3, the current-carrying conductor 2 penetrates into the inner hole of the aluminum coiled tube 3, and the aluminum coiled tube 3 3
  • the surface of the current-carrying conductor 2 in the inner hole is uniformly provided with polytetrafluoroethylene insulating material, which provides mechanical support for the current-carrying conductor 2 and maintains concentricity, and at the same time provides electrical insulation; the indoor end of the aluminum coil tube 3 is crimped
  • the spring 301 maintains an equipotential connection with the current-carrying conductor 2
  • the outdoor section is provided with polytetrafluoroethylene insulating material to maintain electrical insulation with the current-carrying conductor 2 .
  • the current-carrying conductor 2 and the aluminum coiled tube 3 are in the form of a single-point equipotential connection, which avoids the risk of overheating caused by circulating currents caused by multi-point
  • the 800kV flexible DC wall bushing also includes an outdoor end structure 7-1 and an indoor end structure 7, the outdoor end structure 7-1 is arranged at the first end of the sleeve, and the indoor end structure 7 is arranged at the The second end of the sleeve is used to seal the outdoor end of the current-carrying conductor 2 and the first end of the sleeve, and the indoor end of the current-carrying conductor 2 and the second end of the sleeve.
  • the internal structure of the indoor end is shown in Figure 4 and Figure 5, including a first end cover plate 39, a spring compression structure 41, a first general cap 31 and a first top cover 43;
  • the spring compression structure 41 comprises a cylindrical spring Seat 302, spring pressing plate 304 and several spring 301 assemblies;
  • the upper end of spring seat 302 has the first outer flange 307 that extends to outer periphery, and the lower end of spring seat 302 has the second inner flange that extends to inner periphery, and the second The inner flange is provided with a number of first openings distributed along the circumference;
  • the spring pressing plate 304 is circular and matched in the cylindrical spring seat 302, and the spring pressing plate 304 is provided with a hole for the current carrying guide rod a first opening and a plurality of second openings matching the first openings;
  • Each spring 301 assembly includes a spring guide rod 306, a guide rod nut 305, a spring 301, a spring pressure head 303 and a centering nut 308; each spring 301 is arranged between the second inner flange of the spring seat 302 and the spring pressing plate 304;
  • Each spring guide rod 306 passes through the guide rod nut 305, the first opening of the spring pressing plate 304, the spring pressure head 303, the spring 301, the centering nut 308 and the second opening in order to fix the spring 301 on the spring Between the second inner flange of the seat 302 and the spring pressure plate 304;
  • the first end cover plate 39 is provided with a second opening for the current-carrying guide rod to pass through and a groove for the first outer flange 307 of the spring seat 302 to be installed.
  • the first end cover plate 39 is sealingly arranged on the second side of the sleeve.
  • the first general cap 31 is provided with a first inner chamber adapted to the indoor end of the current-carrying guide rod and a third outer flange 307 arranged on the outer peripheral surface of the first inner chamber;
  • the first top The cover 43 is provided with a third opening for the current-carrying guide rod to pass through, and the first top cover 43 is arranged between the third outer flange 307 of the first general cap 31 and the first end cover plate 39 to realize the first general The seal between the cap 31 and the first end cover plate 39 and the spring seat 302; the indoor end of the current-carrying guide rod passes through the lower end of the spring seat 302, the first opening of the spring pressure plate 304, and the upper end of the spring seat 302 in sequence part, the second opening of the first end cover 39 , the third opening of the first top cover 43 and is located in the first inner chamber of the first general cap 31 .
  • the indoor end structure 7 is provided with a spring compression structure 41 and a first pressure equalizing device 42
  • the spring compression structure 41 is used to provide a buffer for the current-carrying conductor 2 when it expands with heat and contracts with cold, so as to prevent the current-carrying conductor 2 from colliding with the first end.
  • the first pressure equalizing device 42 is used to reduce the electric field intensity of the indoor end structure 7 .
  • the indoor end structure 7 also includes a pressure bearing plate 309, a first current-carrying unit, an indoor end flange, an indoor end pressure equalizing device 9 and several sealing rings;
  • the pressure bearing plate 309 is positioned above the spring pressure plate 304 and Sleeved on the current-carrying guide rod;
  • the first current-carrying unit is arranged between the inner circumferential surface of the first inner cavity of the first general cap 31 and the current-carrying guide rod;
  • the first current-carrying unit includes a first upper limit collar , the first lower limit collar and the first strap contact finger arranged between the first upper limit collar and the first lower limit collar;
  • the indoor end flange is sleeved on the outer periphery of the second end of the sleeve and is detachably fixedly connected with the first end cover 39 to fix the first end cover 39 on the second end of the sleeve;
  • the indoor end pressure equalizing device 9 is located between the spring compression structure 41 and the sleeve;
  • several sealing rings include the first flat sealing ring 34, the second flat sealing ring 35, the third flat sealing ring 36, and the fourth flat sealing ring 37 and the first axial sealing ring 38;
  • the first flat sealing ring 34 is arranged between the first general cap 31 and the first top cover 43
  • the second flat sealing ring 35 is arranged between the first top cover 43 and the first end cover plate 39
  • the third flat sealing ring 36 is set at the connection between the first end cover plate 39 and the spring seat 302 of the spring compression structure 41
  • the fourth flat sealing ring 37 is set between the indoor end flange 40 and the first end cover plate 39
  • the first The axial sealing ring 38 is arranged between the current-carrying conductor 2 and the first cover 43 .
  • the first flat sealing ring 34 guarantees the sealing between the first general cap 31 and the first end cover 39
  • the second flat sealing ring 35 guarantees the sealing between the first top cover 43 and the first end cover 39
  • the third The flat sealing ring 36 ensures the sealing between the first end cover plate 39 and the spring compression structure 41
  • the fourth flat sealing ring 37 ensures the sealing between the first end cover plate 39 and the indoor end flange 40
  • the first The axial sealing ring 38 ensures the sealing between the current-carrying conductor 2 and the first cover 43 .
  • the spring compression structure 41 includes a spring seat 302, a spring guide rod 306, and a centering nut 308 , spring pressing head 303 and spring pressing plate 304.
  • the spring seat 302 is provided with a plurality of spring guide rods 306 arranged circumferentially around the current-carrying conductor 2, the spring 301 passes through the spring guide rod 306, the bottom end of the spring 301 is against the centering nut 308 and the top end of the spring 301 is pressed against the spring.
  • the head 303 abuts, the upper end of the spring pressure head 303 abuts against the spring pressing plate 304 and the spring pressing plate 304 is fixed by the guide rod nut 305 .
  • the spring seat 302 is located in the DC wall bushing.
  • the spring 301 is located in the spring seat 302 .
  • the spring 301 is sleeved on the spring guide rod 306 .
  • the spring guide rod 306 is fixedly connected to the spring seat 302 .
  • the bottom end of the spring 301 is against the bottom of the spring seat 302 .
  • the pressure bearing plate 309 is sleeved on the current-carrying conductor 2 .
  • the pressure bearing plate 309 gives the spring 301 downward compression force, and the spring 301 gives the pressure bearing plate 309 an upward axial thrust. Since the pressure bearing plate 309 is pushed upward by the spring 301 , and the pressure bearing plate 309 is connected to the current-carrying conductor 2 , the current-carrying conductor 2 is acted by the upward axial thrust of the spring 301 . Since the current-carrying conductor 2 is subjected to the action of the axial force, the occurrence of deflection will be suppressed, thereby ensuring the uniformity of contact between the current-carrying conductor 2 and the strap contact finger 72 at the end of the bushing, improving the reliability of current-carrying, Avoid malfunctions.
  • the present invention adopts strong spring 301 to provide bushing assembly force to connect the current-carrying conductor 2 and the external parts into a whole with a certain rigidity, wherein the first flange 6 is used to connect the sleeve 21 and the outdoor composite insulator 4, indoor Composite insulator5.
  • the overall mechanical structure of the present invention uses a strong spring 301 to provide casing assembly force, connect the central conduit and external parts into a rigid whole, and ensure that the casing end can be reliably sealed under large bending moments.
  • the strong spring 301 improves the rigidity of the outer insulating hollow composite insulator, reduces the sagging offset of the end of the composite insulator, and reduces the deflection of the central conductive tube at the same time.
  • the central mechanical structure of the present invention adopts a clamping structure, and the connection between the sleeve and the outdoor composite insulator 4 corresponding to the indoor and outdoor ends and the indoor composite insulator 5 adopts the butt joint structure of the first flange 6, and the joint is tightened and connected with high-strength bolts 22, and A buffer washer 24 is also provided at the joint to ensure the service life; a clamping sleeve is provided between the capacitor core 1 and the sleeve to prevent the core from rotating. Since the epoxy material is a brittle material, when the mechanical structure is designed, the core body will be damaged if the local stress of the contact between the metal and the epoxy is too large.
  • the spring compression structure 41 is used to compensate the expansion and contraction of each part under the overall cold and hot state of the bushing, which reduces the extrusion of the capacitor core 1 by the deflection of the central conductive tube; improves the rigidity of the outer insulating hollow composite insulator, and reduces the stress.
  • the offset of the sag at the end is reduced; the pressure of each sealing surface is not less than the sealing requirement when the temperature at the end of the casing changes under the condition of large bending moment under the cold and hot cycle, and the reliability of the overall sealing of the casing is high .
  • the outdoor end structure 7-1 includes a second end cover plate 58, a second general cap 51, a second top cover 61 and Two current-carrying structures 52; the second end cover plate 58 is provided with a fourth opening for the current-carrying guide rod to pass through; the second general cap 51 is provided with a second inner chamber adapted to the outdoor end of the current-carrying guide rod And the fourth outer flange 307 arranged on the outer peripheral surface of the second inner cavity; the second top cover 61 is provided with the fifth opening for the current-carrying guide rod to pass through, and the second top cover 61 is arranged on the second general cap 51 Between the fourth outer flange 307 and the second end cover plate 58, to realize the sealing between the second general cap 51 and the second end cover plate 58; the outdoor end of the current-carrying guide rod passes through the second end cover in turn The fourth opening of the plate 58 and the fifth opening of the second end cover plate 58 are located in the
  • the outdoor end structure 7-1 also includes a second current-carrying unit, an outdoor end flange, an outdoor end pressure equalizing device 9, a fifth flat sealing ring 54, a sixth flat sealing ring 55, a seventh flat sealing ring 56 and The second axial sealing ring 57;
  • the second current-carrying unit is arranged between the inner circumferential surface of the second inner cavity of the second general cap 51 and the current-carrying guide rod;
  • the second current-carrying unit includes a second upper limit collar, The second lower limit collar and the second strap contact finger arranged between the second upper limit collar and the second lower limit collar;
  • the outdoor end flange is sleeved on the outer circumference of the first end of the sleeve and is detachably fixedly connected with the second end cover 58 to fix the second end cover 58 on the first end of the sleeve;
  • Outdoor The end pressure equalizing device 9 is located between the current-carrying guide rod and the sleeve;
  • the fifth flat sealing ring 54 is arranged between the second general cap 51 and the second end cover plate 58, and the sixth flat sealing ring 55 is arranged on the second Between the two top covers 61 and the second end cover plate 58, the seventh flat sealing ring 56 is arranged between the outdoor end flange 59 of the bushing and the second end cover plate 58;
  • the second axial sealing ring 57 is arranged Between the current-carrying conductor 2 and the second top cover 61 .
  • the fifth plane sealing ring 54 guarantees the sealing between the second general cap 51 and the second top cover 61
  • the sixth plane sealing ring 55 guarantees the sealing between the second top cover 61 and the second end cover plate 58
  • the sealing ring 56 ensures the sealing between the second end cover plate 58 and the flange 59
  • the second axial sealing ring 57 ensures the sealing between the current-carrying conductor 233 and the second end cover plate 58 .
  • the outdoor end structure 7-1 is provided with a second voltage equalizing device 60, and the second voltage equalizing device 60 functions to reduce the electric field intensity of the outdoor end structure 7-1.
  • first equalizing device 42 and the second equalizing device 60 are respectively arranged at the two connections between the aluminum coiled tube 3 and the current-carrying conductor 2 . Furthermore, the first pressure equalizing ring 8 is arranged at the first end of the sleeve, and the second pressure equalizing ring 8 is arranged at the second end of the sleeve.
  • the 800kV flexible DC wall bushing includes a first conductive part and a first insulating part, one end of the aluminum coiled tube 3 is equipotentially connected to the current-carrying conductor 2 through the first conductive part, and the other end of the aluminum coiled tube 3
  • the first insulating member is insulated and connected to the current-carrying conductor 2
  • an insulating medium is provided between the aluminum coiled tube 3 and the current-carrying conductor 2 .
  • the first conductive member is a canted coil spring 12 .
  • the first flange 6 is provided with a final panel extraction device 10 , as shown in FIG. 2 , which is a schematic structural diagram of the final panel extraction device 10 .
  • the lead wires 19 of the last screen are welded and fixed on the capacitive screen 81-3 of the last layer, and the last capacitive screen 81-3 is provided with a casing welding point 20 on the last screen, and the lead wires 19 of the last screen are fixed on the test screen by screws.
  • the test tap 13 passes through the tap insulator 14 and forms a whole.
  • the tap insulator 14 is compressed and fixed on the first flange 6 through the compression nut 16.
  • the tap insulator 14 provides mechanical support for the test tap 13 while ensuring its The electrical insulation performance of the first flange 6; the tap insulator 14 and the first flange 6 are provided with a sealing ring 18 and an insulating gasket 17 of the last screen extraction device to ensure the airtightness of the casing air chamber; the last screen cover 11 There is an installation groove inside, the canted coil spring 12 is installed in the installation groove, the last screen cover 11 is fixed on the first flange 6 by screws, the test tap 13 squeezes the canted coil spring 12 and the last screen cover 11 to form a good Electrical connection to achieve good grounding of the test tap 13; a fastening bolt sealing ring 15 is provided between the end screen cover 11 and the first flange 6 to ensure airtight isolation between the inside of the end screen lead-out device 10 and the outside air.
  • the end screen extraction device 10 has a simple structure, reasonable design, and convenient installation, and can realize good grounding and sealing performance of the end screen extraction during casing operation; the good compression and extension performance of the inclined coil spring 12 can ensure repeated disassembly and assembly of the end screen protection Cover 11 can still ensure good contact, and ensure the equipotential connection between the test tap 13 and the end screen cover 11.
  • the casing as a whole is a fully sealed structure.
  • the influence of the SF6 medium in the casing and external environmental factors on the performance of the casing is comprehensively considered.
  • the sealing ring of the corresponding material is selected for the sealing structure design.
  • the main insulation of the bushing adopts the capacitor core 1 impregnated with epoxy resin glue, and the outer insulation adopts the hollow composite insulator.
  • SF6 gas is filled between the capacitor core 1 and the hollow composite insulator.
  • the connection between the first general cap 31 and the wiring board is adopted, and the three plane seals ensure the sealing performance of the head structure and prevent SF6 leakage in the casing.
  • the sealing ring used in this part is made of EPDM.
  • the middle part adopts integral connection sleeve 21.
  • SF6 is filled between the connecting sleeve 21 and the capacitor core 1, the indoor and outdoor air chambers are connected, and a double-plane sealing structure is adopted.
  • the outer sealing ring 25 is made of nitrile rubber, mainly for the corrosion effect of the casing caused by water vapor in the external environment.
  • the inner sealing ring 26 is designed to use EPDM rubber resistant to SF6 gas, which is mainly aimed at the SF6 gas insulation medium in the bushing.
  • the indoor end structure 7 and the outdoor end structure 7-1 are respectively provided with a first current-carrying structure 32 and a second current-carrying structure. 52.
  • the structures of the first current-carrying structure 32 and the second current-carrying structure 52 are not exactly the same.
  • Both the first current-carrying structure 32 and the second current-carrying structure 52 include an upper limit collar 71 and a current-carrying strap contact finger 72
  • the lower limit collar 73, the upper limit collar 71 and the lower limit collar 73 can limit the contact finger 72 of the current-carrying strap to a certain axial direction, avoiding its displacement in the axial direction, and can resist Metal particles or other particles generated by friction inside the connecting sleeve 21 are prevented from entering the current-carrying strap contact fingers 72 and causing the contact resistance of the strap contacts to increase and lead to overheating.
  • the second current-carrying structure 52 is on the outdoor side, the second top cover 61 and the current-carrying conductor 2 are screwed together, and the second general cap 51 and the current-carrying conductor 2 do not slide axially.
  • the first current-carrying structure 32 is on the indoor side, the first general cap 31 and the current-carrying conductor 2 can slide axially under the action of thermal expansion and contraction, and the first axial sealing ring 38 can ensure that the first general cap 31 on the indoor side respectively When the upper limit collar 71 and the lower limit collar 73 and the contact fingers 72 of the current-carrying strap are removed for inspection or replacement, the sleeve pipe as a whole is in a sealed state.
  • the current-carrying structure Due to the complex operating conditions of the bushing, large high-order harmonic values, high heat generation, difficult heat dissipation, prominent heat accumulation problems, significant thermoelectric interaction, and difficult design of the current-carrying structure.
  • the current-carrying structure select the current-carrying design of two different structures, single-conduit and double-conduit, and conduct simulation calculations and comparisons of the temperature field.
  • the technology that adopts the dual-conduit current-carrying structure design is preferred route, thereby reducing the internal heating of the bushing, and avoiding the insulation performance of the epoxy resin capacitor core 1 affected by the current-carrying heat of the conductive tube.
  • the design scheme of the double-conduit current-carrying structure the aluminum coiled tube 3 is responsible for the coiling and mechanical bearing of the capacitor core 1, and the current-carrying conductor 2 is used as a high voltage and current carrier, and the aluminum coil
  • An insulating radial limiting device is provided between the tube 3 and the current-carrying conductor 2 for insulating and isolating the aluminum coiled tube 3 and the current-carrying conductor 2 .
  • An inclined coil spring 12 is used to realize equipotential connection between the outdoor side end of the aluminum coiled tube 3 and the current-carrying conductor 2, and an insulating device is used to insulate and isolate the indoor inner side end to avoid the formation of circulating current between the inner and outer tubes.
  • the outdoor and indoor end parts of the bushing carry current through the current-carrying conductor 2 directly, that is, the outdoor-side current-carrying terminal 41 and the indoor-inside current-carrying terminal 43 realize potential connection with the first general cap 31 respectively through the strap contact fingers, and Insulation limit collars are provided on both sides of the watchband, which avoids local overheating and discharge failures caused by the misalignment between the conductive tube and the first general cap 31 due to its own mechanical gravity during the actual assembly and operation of the sleeve. occur.
  • the capacitor core 1 includes glue-impregnated paper and a multi-layer capacitive screen
  • the multi-layer capacitive screen includes a first layer capacitive screen 81-1, a middle capacitive screen 81-2 and a final layer along the radial direction from inside to outside.
  • the capacitive screen 81-3 wherein, the axial length ratio between the middle capacitive screen 81-2 and the last capacitive screen 81-3, and the radial thickness between the middle capacitive screen 81-2 and the last capacitive screen 81-3 2 times the ratio differs from the preset threshold.
  • the axial length of the first capacitive screen 81-1 is L0
  • the axial length of the last capacitive screen 81-381-3 is Ln
  • the middle The axial length of the capacitive screen 81-281-2 is Lx
  • the radial distance between the first capacitive screen 81-1 and the central axis of the bushing is r0
  • the radial distance between the middle capacitive screen 81-281-2 and the central axis of the bushing is rx
  • the radial distance from the last capacitive screen 81-3 to the central axis of the bushing is rn.
  • ⁇ is the volume resistivity of the glue-impregnated paper material, which can be obtained
  • the size configuration of the multi-layer capacitive screen in the capacitor core 1, the first screen, the middle screen, and the last screen are optimized in radial and axial dimensions, effectively reducing the electric field strength of the first screen and the last screen under DC voltage, and optimizing the capacitor core
  • the electric field intensity distribution in the radial direction of the sub-181 reduces the probability of insulation breakdown of the capacitor core 181.

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Abstract

本发明公开了一种800kV柔性直流穿墙套管，其包括套管内电容芯子、载流导体、户外复合绝缘子、户内复合绝缘子、第一法兰、户内端部结构和户外端部结构、均压环。电容芯子包覆在铝卷制管外部，以第一法兰为轴线形成非对称结构，户外侧电容芯子长度比户内侧电容芯子长；载流导体沿套管内电容芯子以及户外复合绝缘子、户内复合绝缘子的轴心设置，载流导体与铝卷制管接触位置设置有均压装置；户外复合绝缘子、户内复合绝缘子安装在第一法兰两侧，并与户内端部结构、户外端部结构一起形成完整密闭气室。本发明提供的800kV柔性直流穿墙套管具有气密性好、末屏接地牢固、热点温度低、局放量低、电场强度低、绝缘裕度大等优点。

Description

一种800kV柔性直流穿墙套管 技术领域
本发明涉及柔性直流输电电力设备，具体涉及一种800kV柔性直流穿墙套管。
背景技术
柔性直流穿墙套管是柔性直流输电工程的核心设备，柔性直流穿墙套管安装在阀厅墙体上，将阀厅内阀塔设备与直流场平波电抗器等设备建立电气连接。相比常规直流穿墙套管，柔性直流穿墙套管运行工况更加严苛，交直流电压叠加的复杂工况下套管的发热、振动更加强烈，对套管的密封性能、载流结构和接地性能提出了更高的要求。
基于柔直桥臂侧工况，在载流设计方面，柔直套管承载系统桥臂侧交直流复合电流，套管整体温度分布与纯直流套管不同：(1)考虑集肤效应，交流电流分量通过套管载流导体时，电流集中在导体的表层，越靠近导体表面电流密度越大，致使导体损耗增大，温升增高。(2)套管卷制管等金属部件在交变电流产生的磁场作用下内部产生涡流，也会对热场分布产生影响，因此，有必要在套管载流设计时考虑上述因素；
在绝缘结构设计方面：(1)柔直侧桥臂直流电压含有50Hz以上高频谐波分量，需要考虑直流与高频谐波下的电容极板的绝缘设计；(2)特殊的热场分布对套管绝缘材料的电阻率和介电常数分布造成影响，需要考虑电极布置合理分配不同温度的各层绝缘介质在直流及高频谐波下电压的电场，已达到均匀电场的效果。
在机械密封设计方面：套管总长超过20m，水平安装的直流穿墙套管两端受到弯矩作用，套管整体载流结构在热胀冷缩作用下，既要确保一定的伸缩裕度，又要保持与其他零件的配合，确保整体密封性能。
现有常规直流穿墙套管结构的密封结构不良，套管发生漏气的缺陷和故障频繁；现有在运直流穿墙套管发生过多起因绝缘设计不当导致的电气故障；同时，直流穿墙套管载流结构的设计缺陷在运行时将导致套管的过热缺陷；上述问题严重影响直流穿墙套管和直流输电工程的稳定运行。
同时，现有的直流穿墙套管的配置，特别是电容芯子多层电容屏的尺寸配置以及多层电容屏的径向尺寸和轴向尺寸，会对首屏和末屏的电场强度造成影响，使电容芯子发生绝缘击穿的概率较高。
发明内容
针对现有技术中的不足，本发明提供一种柔性直流穿墙套管，适用于柔性直流桥臂侧运行工况，解决以往常规直流穿墙套管电场分布不均匀，电容芯子容易发生绝缘击穿的问题。为实现上述目的，本发明采 取的技术方案是：
一种800kV柔性直流穿墙套管，包括套筒和设置在所述套筒内的电容芯子，所述800kV柔性直流穿墙套管还包括第一法兰、户外复合绝缘子、户内复合绝缘子、载流导体和铝卷制管；
所述第一法兰设置在所述套筒上，所述第一法兰把所述套筒分成户外段和户内段；所述户外复合绝缘子和所述户内复合绝缘子通过所述第一法兰分别固定套设在所述套筒的户外段和户内段；
所述载流导体穿过所述铝卷制管并与所述铝卷制管同轴间隔设置，所述载流导体具有户外端部和户内端部，所述载流导体的户外端部和户内端部穿过所述铝卷制管并分别穿出所述套筒的户外段远离所述第一法兰的第一端部和所述套筒的户内段远离所述第一法兰的第二端；所述铝卷制管的两端均与所述载流导体连接；
所述电容芯子包括多层胶浸纸和多层电容屏，所述多层胶浸纸和多层电容屏依次交替绕设在所述铝卷制管上；所述多层电容屏包括沿径向从内到外的首层电容屏、中间电容屏和末层电容屏，其中，所述中间电容屏与所述末层电容屏的轴向长度比值，与，所述中间电容屏与所述末层电容屏之间的径向厚度比值的2倍相差预设阈值。
本发明通过采用载流导体和铝卷制管的双导管载流结构，通过铝卷制管承担电容芯子的卷制和机械承载，通过载流导体作为高压和电流的承载，进而减少了套管内部发热，避免因为载流导体的载流发热二影响电容芯子绝缘性能；此外，通过对中间电容屏与所述末层电容屏的轴向长度以及中间电容屏与所述末层电容屏之间的绝缘层的径向厚度进行优化设计，有效降低首屏和末屏的电场强度，优化电容芯子轴向和径向电场强度分布，以防止局部电场增大而使得电容芯子发生绝缘击穿，大大降低了电容芯子发生绝缘击穿的概率。
进一步地，所述预设阈值的范围为0cm-2cm。
进一步地，所述800kV柔性直流穿墙套管还包括户外端部结构和户内端部结构，所述户外端部结构设置在所述套筒的第一端部处，所述户内端部结构设置在所述套筒的第二端部处，以分别对所述载流导体的户外端部和所述套筒的第一端部、以及所述载流导体的户内端部和所述套筒的第二端部进行密封。
进一步地，所述户内端部结构包括第一端盖板、弹簧压缩结构、第一将军帽和第一顶盖；
所述弹簧压缩结构包括呈圆筒状的弹簧座、弹簧压板和若干弹簧组件；
所述弹簧座的上端部具有向外周延伸的第一外凸缘，所述弹簧座的下端部具有向内周延伸的第二内凸缘，所述第二内凸缘上设置有若干沿圆周分布的第一开孔；
所述弹簧压板呈圆形状并匹配设置在呈圆筒状的弹簧座内，所述弹簧压板上设置有供所述载流导杆穿过的第一开口和与所述第一开孔匹配的若干第二开孔；
每一所述弹簧组件均包括弹簧导杆、导杆螺母、弹簧、弹簧压头和定心螺母；每一所述弹簧设置在所 述弹簧座的第二内凸缘和所述弹簧压板之间，每一所述弹簧导杆依次穿过所述导杆螺母、所述弹簧压板的第一开孔、所述弹簧压头、所述弹簧、所述定心螺母和所述第二开孔，以将所述弹簧固定在所述弹簧座的第二内凸缘和所述弹簧压板之间；
所述第一端盖板设置有供所述载流导杆穿过的第二开口和供所述弹簧座的第一外凸缘安装的凹槽，所述第一端盖板密封设置在所述套筒的第二端部上；
所述第一将军帽设置有与所述载流导杆的户内端部相适配的第一内腔和设置在所述第一内腔的外周面的第三外凸缘；
所述第一顶盖设置有供所述载流导杆穿过的第三开口，所述第一顶盖设置在所述第一将军帽的第三外凸缘与所述第一端盖板之间，以实现所述第一将军帽与所述第一端盖板以及所述弹簧座之间的密封；
所述载流导杆的户内端部依次穿过所述弹簧座的下端部、所述弹簧压板的第一开口、所述弹簧座的上端部、所述第一端盖板的第二开口、所述第一顶盖第三开口并位于所述第一将军帽的第一内腔中。
通过在户内端部结构中采用弹簧压缩结构，以对穿墙套管整体在冷热状态下的各部位伸缩量进行受力补偿，减小了中心的载流导杆挠度对电容芯子的挤压，提高了绝缘空心复合绝缘子的钢性，减小了其端部下垂的偏移量；保证了穿墙套管端部在大弯矩条件下、在冷热循环下变化时各密封面的压强不小于的密封要求，使得穿墙套管整体密封的可靠性高。
进一步地，所述户内端部结构还包括承压板和第一载流单元；
所述承压板位于所述弹簧压板的上方并套接在所述载流导杆上；所述第一载流单元设置在所述第一将军帽的第一内腔的内圆周表面和所述载流导杆之间；所述第一载流单元包括第一上限位卡圈、第一下限位卡圈和设置在所述第一上限位卡圈和第一下限位卡圈之间的第一表带触指。
通过在所述弹簧压板的上方设置与所述载流导杆套接的承压板，在运行时，在承压板给位于弹簧压板下方的弹簧施加向下的压缩力时，所述弹簧则给所述承压板向上的轴向推力，而承压板与载流导杆为连接关系，使得载流导杆受到弹簧向上的轴向推力作用，抑制载流导杆扰度变化，从而确保了载流导杆与户内端部结构的表带触指接触的均匀性，保证了载流的可靠性，避免故障的发生。
进一步地，所述户内端部结构还包括户内端法兰盘、户内端部均压装置和若干密封圈；
所述户内端法兰盘套设在所述套筒的第二端部的外周并与所述第一端盖板可拆卸固定连接，以将所述第一端盖板固定在所述套筒的第二端部上；
所述户内端部均压装置位于在所述弹簧压缩结构和所述套筒之间；
所述若干密封圈包括第一平面密封圈、第二平面密封圈、第三平面密封圈、第四平面密封圈和第一轴向密封圈；
所述第一平面密封圈设置在所述第一将军帽与所述第一顶盖之间，所述第二平面密封圈设置在所述第 一顶盖与所述第一端盖板之间，所述第三平面密封圈设置在所述第一端盖板与所述弹簧压缩结构的弹簧座的连接处，所述第四平面密封圈设置在所述户内端部法兰盘与所述第一端盖板之间，所述第一轴向密封圈设置在所述载流导体与所述第一顶盖之间。
通过户内端法兰盘的设置，以将第一端盖板固定在所述套筒的第二端部上，通过户内端部均压装置的设置保证了户内端部的电场分布的均匀性；而密封圈的设置则进一步保证了户内端部结构与套筒之间的密封性。
进一步地，所述户外端部结构包括第二端盖板、第二将军帽、第二顶盖和第二载流结构；
所述第二端盖板设置有供所述载流导杆穿过的第四开口；
所述第二将军帽设置有与所述载流导杆的户外端部相适配的第二内腔和设置在所述第二内腔的外周面的第四外凸缘；
所述第二顶盖设置有供所述载流导杆穿过的第五开口，所述第二顶盖设置在所述第二将军帽的第四外凸缘与所述第二端盖板之间，以实现所述第二将军帽与所述第二端盖板之间的密封；
所述载流导杆的户外端部依次穿过第二端盖板的第四开口、所述第二端盖板的第五开口并位于所述第二将军帽的第二内腔中。
进一步地，所述户外端部结构还包括第二载流单元，所述第二载流单元设置在所述第二将军帽的第二内腔的内圆周表面和所述载流导杆之间；所述第二载流单元包括第二上限位卡圈、第二下限位卡圈和设置在所述第二上限位卡圈和第二下限位卡圈之间的第二表带触指。
通过表带触指将载流导杆与第二将军帽电位连接，并在表带两侧设置绝缘限位卡圈，避免了穿墙套管在实际装配完成及运行过程中由于自身机械重力导致的载流导杆与端部密封结构不同轴造成的局部过热和放电故障的发生。
进一步地，所述户外端部结构还包括户外端法兰盘、户外端部均压装置、第五平面密封圈、第六平面密封圈、第七平面密封圈和第二轴向密封圈；
所述户外端法兰盘套设在所述套筒的第一端部的外周并与所述第二端盖板可拆卸固定连接，以将所述第二端盖板固定在所述套筒的第一端部上；
所述户外端部均压装置位于在所述载流导杆和所述套筒之间；
所述第五平面密封圈设置在所述第二将军帽与所述第二端盖板之间，所述第六平面密封圈设置在所述第二顶盖与所述第二端盖板之间，所述第七平面密封圈设置在所述套管的户外端部法兰盘与所述第二端盖板之间；所述第二轴向密封圈设置在所述载流导体与所述第二顶盖之间。
进一步地，所述800kV柔性直流穿墙套管包括第一导电件和第一绝缘件，所述铝卷制管的一端通过所述第一导电件与所述载流导体等电位连接，所述铝卷制管的另一端通过所述第一绝缘件与所述载流导体绝 缘连接，所述铝卷制管和所述载流导体之间设置有绝缘介质。
通过将所述铝卷制管的一端与所述载流导体等电位连接，所述铝卷制管的另一端与所述载流导体绝缘连接，避免了载流导体和铝卷制管之间形成环流而影响穿墙套管的性能；而在所述铝卷制管和所述载流导体之间设置绝缘介质，以对所述载流导体和铝管制管进行绝缘支撑，保证载流导体和铝管制管同轴性。
进一步地，所述第一导电件为斜圈弹簧。
进一步地，所述800kV柔性直流穿墙套管还包括第一均压装置和第二均压装置，所述第一均压装置和所述第二均压装置分别设置在所述铝卷制管与所述载流导体的两个连接处。
进一步地，所述800kV柔性直流穿墙套管还包括第一均压环和第二均压环，所述第一均压环设置在所述套筒的第一端部，所述第二均压环设置在所述套筒的第二端部。
进一步地，所述套筒的户外段和户内段为非对称结构，位于所述户外段内的电容芯子的长度大于位于所述户内段的电容芯子的长度。
附图说明
为了更清楚地说明本发明实施例中的技术方案，下面将对实施例中所需要使用的附图进行简单的介绍，显而易见地，下面描述中的附图仅仅是本申请的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。
图1为本发明实施例的800kV柔性直流穿墙套管的结构示意图；
图2为本发明实施例的末屏引出装置的结构示意图；
图3为本发明实施例的套管中部结构的结构示意图；
图4为本发明实施例的户内端部结构的结构示意图；
图5为本发明实施例的户内端部结构的另一种使用形式的结构示意图；
图6为本发明实施例的弹簧压缩装置的结构示意图，其中，图6(a)为弹簧压缩结构的结构示意图，图6(b)为装配有弹簧压缩结构的头部结构示意图；
图7为本发明实施例的户外端部结构的结构示意图；
图8为本发明实施例的套管密封结构的设计示意图；其中，图8(a)为户内端密封结构；图8(b)为户外端密封结构；图8(c)为中部密封结构；
图9为本发明实施例的双导管载流结构示意图；
图10为户内端部结构和户外端部结构的载流结构示意图；
图11为电容芯子的结构示意图。
附图标记说明：1、电容芯子；2、载流导体；3、铝卷制管；4、户外复合绝缘子；5、户内复合绝缘子； 6、第一法兰；7、户内端部结构；7-1、户外端部结构；8、均压环；9、均压装置；10、末屏引出装置；
11、末屏护盖；12、斜圈弹簧；13、试验抽头；14、抽头绝缘子；15、紧固螺栓密封圈；16、压紧螺母；17、绝缘垫圈；18、末屏引出装置密封圈；19、末屏引出线；20、套管末屏焊接点；
21、连接套筒；22、高强度螺栓；23、空套；24、缓冲垫圈；25、外侧密封圈；26、内侧密封圈；
31、第一将军帽；32、第一载流结构；34、第一平面密封圈；35、第二平面密封圈；36、第三平面密封圈；37、第四平面密封圈；38、第一轴向密封圈；39、第一端盖板；40、户内端部法兰盘；41、弹簧压缩结构；42、第一均压装置；43、第一顶盖；
301、弹簧；302、弹簧座；303、弹簧压头；304、弹簧压板；305、导杆螺母；306、弹簧导杆；307、外凸缘；308、定心螺母；309、承压板；
41、户外侧载流端子；43、户内侧载流端子；
51、第二将军帽；52、第二载流结构；54、第五平面密封圈；55、第六平面密封圈；56、第七平面密封圈；57、第二轴向密封圈；58、第二端盖板；59、户外端部法兰盘；60、第二均压装置；61、第二顶盖；
71、上部限位卡圈；72、载流表带触指；73、下部限位卡圈；
81-1、首层电容屏；81-2、中间电容屏；81-3、末层电容屏。
具体实施方式
下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清楚、完整的描述，显然，所描述的实施例仅是本申请一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本申请保护的范围。
实施例：
需要说明的是，本发明的说明书和权利要求书及上述附图中的术语“第一”、“第二”等是用于区别类似的对象，而不必用于描述特定的顺序或先后次序。应该理解这样使用的数据在适当情况下可以互换，以便这里描述的本发明的实施例能够以除了在这里图示或描述的那些以外的顺序实施。此外，本发明实施例的术语“包括”和“具有”以及他们的任何变形，意图在于覆盖不排他的包含，例如，包含了一系列步骤或单元的过程、方法、系统、产品或设备不必限于清楚地列出的那些步骤或单元，而是可包括没有清楚地列出的或对于这些过程、方法、产品或设备固有的其它步骤或单元。
需要理解的是，术语“中心”、“纵向”、“横向”、“长度”、“宽度”、“厚度”、“上”、“下”、“前”、“后”、“左”、“右”、“竖直”、“水平”、“顶”、“底”、“内”、“外”、“顺时针”、“逆时针”、“轴向”、“径向”、“周向”等指示的方位或位置关系为基于附图所示的方位或位置关系，仅是为了便于描述本发明和简化描述，而不是指示或暗示所指的装置或元件必须具有特定的方位、以特定 的方位构造和操作，因此不能理解为对本发明的限制。
在本发明的描述中，“多个”的含义是至少两个，例如两个、三个等，除非另有明确具体的限定。此外，除非另有明确的规定和限定，术语“安装”、“相连”、“连接”应做广义理解，例如，可以是固定连接，也可以是可拆卸连接，或一体地连接；可以是机械连接，也可以是电连接；可以是直接相连，也可以通过中间媒介间接相连，可以是两个元件内部的连通。对于本领域的普通技术人员而言，可以具体情况理解上述术语在本发明中的具体含义。
在本发明中，除非另有明确的规定和限定，第一特征在第二特征“上”或“下”可以是第一和第二特征直接接触，或第一和第二特征通过中间媒介间接接触。而且，第一特征在第二特征“之上”、“上方”和“上面”可是第一特征在第二特征正上方或斜上方，或仅仅表示第一特征水平高度高于第二特征。第一特征在第二特征“之下”、“下方”和“下面”可以是第一特征在第二特征正下方或斜下方，或仅仅表示第一特征水平高度小于第二特征。
参见图1至图11，本发明提供一种800kV柔性直流穿墙套管，以解决以往常规直流穿墙套管电场分布不均匀，电容芯子容易发生绝缘击穿的问题。
参见图1，包括套筒和设置在套筒内的电容芯子1，800kV柔性直流穿墙套管还包括第一法兰6、户外复合绝缘子4、户内复合绝缘子5、载流导体2和铝卷制管3；第一法兰6设置在套筒上，第一法兰6把套筒分成户外段和户内段；户外复合绝缘子4和户内复合绝缘子5通过第一法兰6分别固定套设在套筒的户外段和户内段；
载流导体2穿过铝卷制管3并与铝卷制管3同轴间隔设置，载流导体2具有户外端部和户内端部，载流导体2的户外端部和户内端部穿过铝卷制管3并分别穿出套筒的户外段远离第一法兰6的第一端部和套筒的户内段远离第一法兰6的第二端部；铝卷制管3的两端均与载流导体2连接；
电容芯子1包括多层胶浸纸和多层电容屏，多层胶浸纸和多层电容屏依次交替绕设在铝卷制管3上；多层电容屏包括沿径向从内到外的首层电容屏81-1、中间电容屏81-2和末层电容屏81-3，其中，中间电容屏81-2与末层电容屏81-3的轴向长度比值，与，中间电容屏81-2与末层电容屏81-3之间的径向厚度比值的2倍相差预设阈值。本发明可实现对载流导体2的电气绝缘和机械支撑。优选的，预设阈值的范围为0cm-2cm；载流导体2为铜杆载流导体2。
优选的，套筒的户外段和户内段为非对称结构，位于户外段内的电容芯子1的长度大于位于户内段的电容芯子1的长度。
本发明通过采用载流导体2和铝卷制管3的双导管载流结构，通过铝卷制管3承担电容芯子1的卷制和机械承载，通过载流导体2作为高压和电流的承载，进而减少了套管内部发热，避免因为载流导体2的载流发热而影响电容芯子1绝缘性能。
此外，通过对中间电容屏81-2与末层电容屏81-3的轴向长度以及中间电容屏81-2与末层电容屏81-3之间的绝缘层的径向厚度进行优化设计，有效降低首屏和末屏的电场强度，优化电容芯子1轴向和径向电场强度分布，以防止局部电场增大而使得电容芯子1发生绝缘击穿，大大降低了电容芯子1发生绝缘击穿的概率。
作为一种可选的实施方式，在某些实施例中，载流导体2与铝卷制管3同轴设置，载流导体2穿入铝卷制管3的内孔，在铝卷制管3内孔中载流导体2表面均匀设置有聚四氟乙烯绝缘材料，为载流导体2提供机械支撑和保持同心度的同时，提供电气绝缘；铝卷制管3户内端部通过压接弹簧301与载流导体2保持等电位连接，户外段设置聚四氟乙烯绝缘材料与载流导体2保持电气绝缘。载流导体2与铝卷制管3采用单点等电位连接的形式，避免了因多点等电位连接产生环流后引起过热的风险。
800kV柔性直流穿墙套管还包括户外端部结构7-1和户内端部结构7，户外端部结构7-1设置在套筒的第一端部处，户内端部结构7设置在套筒的第二端部处，以分别对载流导体2的户外端部和套筒的第一端部、以及载流导体2的户内端部和套筒的第二端部进行密封。
户内端内部结构如图4和图5所示，包括第一端盖板39、弹簧压缩结构41、第一将军帽31和第一顶盖43；弹簧压缩结构41包括呈圆筒状的弹簧座302、弹簧压板304和若干弹簧301组件；弹簧座302的上端部具有向外周延伸的第一外凸缘307，弹簧座302的下端部具有向内周延伸的第二内凸缘，第二内凸缘上设置有若干沿圆周分布的第一开孔；弹簧压板304呈圆形状并匹配设置在呈圆筒状的弹簧座302内，弹簧压板304上设置有供载流导杆穿过的第一开口和与第一开孔匹配的若干第二开孔；
每一弹簧301组件均包括弹簧导杆306、导杆螺母305、弹簧301、弹簧压头303和定心螺母308；每一弹簧301设置在弹簧座302的第二内凸缘和弹簧压板304之间，每一弹簧导杆306依次穿过导杆螺母305、弹簧压板304的第一开孔、弹簧压头303、弹簧301、定心螺母308和第二开孔，以将弹簧301固定在弹簧座302的第二内凸缘和弹簧压板304之间；
第一端盖板39设置有供载流导杆穿过的第二开口和供弹簧座302的第一外凸缘307安装的凹槽，第一端盖板39密封设置在套筒的第二端部上；第一将军帽31设置有与载流导杆的户内端部相适配的第一内腔和设置在第一内腔的外周面的第三外凸缘307；第一顶盖43设置有供载流导杆穿过的第三开口，第一顶盖43设置在第一将军帽31的第三外凸缘307与第一端盖板39之间，以实现第一将军帽31与第一端盖板39以及弹簧座302之间的密封；载流导杆的户内端部依次穿过弹簧座302的下端部、弹簧压板304的第一开口、弹簧座302的上端部、第一端盖板39的第二开口、第一顶盖43第三开口并位于第一将军帽31的第一内腔中。
由于户内端部结构7设置有弹簧压缩结构41和第一均压装置42，弹簧压缩结构41用于为载流导体2提供热胀冷缩时的缓冲，避免载流导体2与第一端盖板39硬连接时因载流导体2热胀冷缩导致的异常受力， 第一均压装置42用于降低户内端部结构7的电场强度的作用。
户内端部结构7还包括承压板309、第一载流单元、户内端法兰盘、户内端部均压装置9和若干密封圈；承压板309位于弹簧压板304的上方并套接在载流导杆上；第一载流单元设置在第一将军帽31的第一内腔的内圆周表面和载流导杆之间；第一载流单元包括第一上限位卡圈、第一下限位卡圈和设置在第一上限位卡圈和第一下限位卡圈之间的第一表带触指；
户内端法兰盘套设在套筒的第二端部的外周并与第一端盖板39可拆卸固定连接，以将第一端盖板39固定在套筒的第二端部上；户内端部均压装置9位于在弹簧压缩结构41和套筒之间；若干密封圈包括第一平面密封圈34、第二平面密封圈35、第三平面密封圈36、第四平面密封圈37和第一轴向密封圈38；
第一平面密封圈34设置在第一将军帽31与第一顶盖43之间，第二平面密封圈35设置在第一顶盖43与第一端盖板39之间，第三平面密封圈36设置在第一端盖板39与弹簧压缩结构41的弹簧座302的连接处，第四平面密封圈37设置在户内端部法兰盘40与第一端盖板39之间，第一轴向密封圈38设置在载流导体2与第一顶盖43之间。第一平面密封圈34保证第一将军帽31与第一端盖板39之间的密封，第二平面密封圈35保证第一顶盖43与第一端盖板39之间的密封，第三平面密封圈36保证第一端盖板39与弹簧压缩结构41之间的密封，第四平面密封圈37保证第一端盖板39与户内端部法兰盘40之间的密封，第一轴向密封圈38保证载流导体2与第一顶盖43之间的密封。
作为一种可选的实施方式，在某些实施例中，如图6(a)和图6(b)所示，弹簧压缩结构41包括有弹簧座302、弹簧导杆306、定心螺母308、弹簧压头303和弹簧压板304。弹簧座302内设有多根绕载流导体2周向设置的弹簧导杆306，弹簧301穿过弹簧导杆306，弹簧301的底端与定心螺母308相抵且弹簧301的顶端与弹簧压头303相抵，弹簧压头303的上端抵接有弹簧压板304且弹簧压板304被导杆螺母305固定。具体地，弹簧座302位于直流穿墙套管内。弹簧301位于弹簧座302内。弹簧301套设在弹簧导杆306上。弹簧导杆306固连在弹簧座302上。弹簧301的底端抵在弹簧座302的底部。承压板309套接在载流导体2上。承压板309给弹簧301向下的压缩力，弹簧301给承压板309向上的轴向推力。由于承压板309受到弹簧301向上的轴向推力，而承压板309与载流导体2为连接关系，因此载流导体2受到弹簧301向上的轴向推力作用。由于载流导体2受到了轴向力的作用，因此会抑制挠度的发生，从而确保了载流导体2与套管端部表带触指72接触的均匀性，提高了载流的可靠性，避免故障的发生。
本发明采用强力弹簧301提供套管装配力，以将载流导体2与外部零件连接成具有一定刚性的整体，其中，第一法兰6用于连接套筒21与户外复合绝缘子4、户内复合绝缘子5。具体地，本发明整体机械结构采用强力弹簧301提供套管装配力，将中心导管与外部零件连接成具有一定刚性的整体，保证套管端部在大弯矩条件下能够可靠密封。强力弹簧301提高了外绝缘空心复合绝缘子的钢性，减小了复合绝缘子端部下垂的偏移量，同时减小了中心导电管挠度。本发明中部机械结构采用卡装结构，套筒与户内外两端对 应的户外复合绝缘子4和户内复合绝缘子5连接采用第一法兰6对接结构，对接处用高强度螺栓22拧紧连接，且对接处还设置有缓冲垫圈24以保证使用寿命；电容芯子1与套筒之间设置有夹紧套，防止芯体转动。由于环氧材料为脆性材料，在机械结构设计时，凡是金属与环氧接触局部应力过大对芯体造成损伤。
采用弹簧压缩结构41对套管整体冷热状态下各部位伸缩量进行受力补偿，减小了中心导电管挠度对电容芯子1的挤压；提高了外绝缘空心复合绝缘子的钢性，减小了其端部下垂的偏移量；保证了套管端部在大弯矩条件下温度在冷热循环下变化时各密封面的压强不小于的密封要求，套管整体密封的可靠性高。
作为一种可选的实施方式，在某些实施例中，如图7所示，户外端部结构7-1包括第二端盖板58、第二将军帽51、第二顶盖61和第二载流结构52；第二端盖板58设置有供载流导杆穿过的第四开口；第二将军帽51设置有与载流导杆的户外端部相适配的第二内腔和设置在第二内腔的外周面的第四外凸缘307；第二顶盖61设置有供载流导杆穿过的第五开口，第二顶盖61设置在第二将军帽51的第四外凸缘307与第二端盖板58之间，以实现第二将军帽51与第二端盖板58之间的密封；载流导杆的户外端部依次穿过第二端盖板58的第四开口、第二端盖板58的第五开口并位于第二将军帽51的第二内腔中。
户外端部结构7-1还包括第二载流单元、户外端法兰盘、户外端部均压装置9、第五平面密封圈54、第六平面密封圈55、第七平面密封圈56和第二轴向密封圈57；第二载流单元设置在第二将军帽51的第二内腔的内圆周表面和载流导杆之间；第二载流单元包括第二上限位卡圈、第二下限位卡圈和设置在第二上限位卡圈和第二下限位卡圈之间的第二表带触指；
户外端法兰盘套设在套筒的第一端部的外周并与第二端盖板58可拆卸固定连接，以将第二端盖板58固定在套筒的第一端部上；户外端部均压装置9位于在载流导杆和套筒之间；第五平面密封圈54设置在第二将军帽51与第二端盖板58之间，第六平面密封圈55设置在第二顶盖61与第二端盖板58之间，第七平面密封圈56设置在套管的户外端部法兰盘59与第二端盖板58之间；第二轴向密封圈57设置在载流导体2与第二顶盖61之间。第五平面密封圈54保证第二将军帽51与第二顶盖61之间的密封，第六平面密封圈55保证第二顶盖61与第二端盖板58之间的密封，第七平面密封圈56保证第二端盖板58与法兰盘59之间的密封，第二轴向密封圈57保证载流导体233与第二端盖板58之间的密封。户外端部结构7-1设置有第二均压装置60，第二均压装置60起到降低户外端部结构7-1的电场强度的作用。
进一步的，第一均压装置42和第二均压装置60分别设置在铝卷制管3与载流导体2的两个连接处。更进一步的，第一均压环8设置在套筒的第一端部，第二均压环8设置在套筒的第二端部。
进一步的，800kV柔性直流穿墙套管包括第一导电件和第一绝缘件，铝卷制管3的一端通过第一导电件与载流导体2等电位连接，铝卷制管3的另一端通过第一绝缘件与载流导体2绝缘连接，铝卷制管3和载流导体2之间设置有绝缘介质。
通过将所述铝卷制管3的一端与所述载流导体2等电位连接，所述铝卷制管3的另一端与所述载流导 体2绝缘连接，避免了载流导体2和铝卷制管3之间形成环流而影响穿墙套管的性能；而在所述铝卷制管3和所述载流导体2之间设置绝缘介质，以对所述载流导体2和铝管制管进行绝缘支撑，保证载流导体2和铝管制管同轴性。优选的，第一导电件为斜圈弹簧12。
作为一种可选的实施方式，在某些实施例中，第一法兰6设置有末屏引出装置10，如图2所示，图2为末屏引出装置10的结构示意图。
详细的说，末屏引出线19焊接固定在末层电容屏81-3上，末层电容屏81-3上设置有套管末屏焊接点20上，末屏引出线19通过螺丝固定在试验抽头13下端，试验抽头13穿过抽头绝缘子14并形成整体，抽头绝缘子14通过压紧螺母16压紧固定在第一法兰6上，抽头绝缘子14为试验抽头13提供机械支撑作用的同时保证其对第一法兰6的电气绝缘性能；抽头绝缘子14与第一法兰6间设置有末屏引出装置密封圈18和绝缘垫圈17，保证套管气室的气密性；末屏护盖11内部设置有安装槽，斜圈弹簧12安装在安装槽内，末屏护盖11通过螺丝固定在第一法兰6上，试验抽头13挤压斜圈弹簧12与末屏护盖11形成良好的电气连接，实现试验抽头13的良好接地；末屏护盖11与第一法兰6间设置有紧固螺栓密封圈15，保证末屏引出装置10内部与外界空气之间气密隔绝。该末屏引出装置10结构简单、设计合理、安装方便，可实现套管运行时末屏引出的良好接地和密封性能；斜圈弹簧12良好的压缩和伸展性能可保证重复的拆装末屏护盖11后仍能保证良好的接触，保证试验抽头13与末屏护盖11之间的等电位连接。
具体地，如图8(a)、(b)和(c)所示，本发明的套管采用以下密封设计思路：
(1)基本密封结构设计
套管整体为全密封结构，在密封结构设计时，综合考虑套管内SF6介质和外部环境因素对套管性能的影响，针对不同部位的密封要求，选择对应材质的密封圈进行密封结构设计。
套管的主绝缘采用环氧树脂胶浸纸电容芯子1，外绝缘选用空心复合绝缘子，电容芯子1和空心复合绝缘子之间充SF6气体，户内、外空套23气室连通，可满足套管在各种环境下的绝缘强度及局放要求，与SF6介质接触的部位均采用耐SF6气体的三元乙丙橡胶。
套管运行时，户内端处于阀厅内，阀厅内为微正压状态，户外端则直接暴漏在大气环境中，在套管密封结构设计时，如图3所示，在中部连接套筒21与两端空套23、连接套管21的头部与空套23对接位置均采用双密封结构设计，结合密封圈的使用压缩范围，避免双密封在密封效果上存在的相互干扰，外侧密封设计时密封圈的压缩率略低于内侧密封设计。
(2)头部密封结构优化
采用第一将军帽31与接线板连接的方式，三道平面密封保证头部结构的密封性能，防止套管内SF6泄露。该部位使用的密封圈材质为三元乙丙。
中部采用整体连接套筒21。连接套筒21与电容芯子1之间充SF6，户内外气室连通，采用双平面密封 结构，外侧密封圈25选用丁腈橡胶，主要针对外部环境中水汽等对套管造成的锈蚀影响，内侧密封圈26设计采用耐SF6气体的三元乙丙橡胶，主要针对套管内SF6气体绝缘介质。
作为一种可选的实施方式，在某些实施例中，如图10所示，户内端部结构7和户外端部结构7-1分别设置第一载流结构32和第二载流结构52，第一载流结构32和第二载流结构52的结构不完全一致，第一载流结构32和第二载流结构52均包括上部限位卡圈71、载流表带触指72以及下部限位卡圈73，上部限位卡圈71和下部限位卡圈73可将载流表带触指72限制在一定的轴向为主，避免其在轴向发生位移，同时可抵挡连接套管21内部由于摩擦产生的金属颗粒或其他颗粒物，避免金属颗粒或其他颗粒物进入载流表带触指72导致表带触指接触电阻变大而引出过热。第二载流结构52在户外侧，第二顶盖61与载流导体2结构采用螺纹连接，第二将军帽51与载流导体2不发生轴向滑动。第一载流结构32在户内侧，第一将军帽31与载流导体2可在热胀冷缩作用下发生轴向滑动，第一轴向密封圈38可保证户内侧第一将军帽31分别和上部限位卡圈71以及下部限位卡圈73及载流表带触指72拆除检查或更换时，套管整体处于密封状态。
由于套管运行工况复杂，高次谐波值大，发热多，散热难，聚热问题突出，热电相互影响显著，载流结构设计难度大。载流结构设计时，选取单导管和双导管两种不同结构的载流设计，并进行温度场仿真计算对比，综合考虑套管整体热场分布规律，优先选取采用双导管载流结构设计的技术路线，进而减少套管内部发热，避免因为导电管载流发热影响环氧树脂电容芯子1绝缘性能。
具体地，如图9所示，双导管载流结构设计方案：既铝卷制管3承担电容芯子1的卷制和机械承载，载流导体2作为高压和电流的承载，且在铝卷制管3与载流导体2之间设置有绝缘径向限位装置，用以铝卷制管3与载流导体2的绝缘隔离。铝卷制管3户外侧端部与载流导体2之间采用斜圈弹簧12实现等电位连接，户内侧端部采用绝缘装置进行绝缘隔离，避免内外管之间形成环流。
套管户外、户内侧端部载流采用载流导体2直接伸出，即户外侧载流端子41和户内侧载流端子43分别通过表带触指与第一将军帽31实现电位连接，并在表带两侧设置有绝缘限位卡圈，避免了套管在实际装配完成及运行过程中由于自身机械重力导致的导电管与第一将军帽31不同轴造成的局部过热和放电故障的发生。
如图11所示，电容芯子1包括胶浸纸和多层电容屏，多层电容屏包括沿径向从内到外的首层电容屏81-1、中间电容屏81-2和末层电容屏81-3，其中，中间电容屏81-2与末层电容屏81-3的轴向长度比值，与，中间电容屏81-2与末层电容屏81-3之间的径向厚度比值的2倍相差预设阈值。
在本发明中，以设有一层中间电容屏81-2为例，设首层电容屏81-1的轴向长度为L0，末层电容屏81-381-3的轴向长度为Ln，中间电容屏81-281-2的轴向长度为Lx，首层电容屏81-1距套管中心轴线的径向距离为r0，中间电容屏81-281-2距套管中心轴线的径向距离为rx，末层电容屏81-3距套管中心轴线的径 向距离为rn。
为了使套管每层电容屏轴向场强相等，使得每层上、下台阶长度相等，则得到l x＝l n+(n-x)(λ 1+λ 2)，使每一层在直流电压下的电阻分布相同，则得到：
Figure PCTCN2021131759-appb-000001
ρ为胶浸纸材料的体积电阻率，可以得到
Figure PCTCN2021131759-appb-000002
Figure PCTCN2021131759-appb-000003
电容芯子1中多层电容屏的尺寸配置，首屏、中间屏、末屏在径向尺寸和轴向尺寸上优化配置，有效降低直流电压下首屏和末屏的电场强度，优化电容芯子181径向电场强度分布，降低电容芯子181发生绝缘击穿的概率。
在本说明书的描述中，参考术语“一个实施例”、“一些实施例”、“示例”、“具体示例”、或“一些示例”等的描述意指结合该实施例或示例描述的具体特征、结构、材料或者特点包含于本发明的至少一个实施例或示例中。在本说明书中，对上述术语的示意性表述不必须针对的是相同的实施例或示例。而且，描述的具体特征、结构、材料或者特点可以在任一个或多个实施例或示例中以合适的方式结合。此外，在不相互矛盾的情况下，本领域的技术人员可以将本说明书中描述的不同实施例或示例以及不同实施例或示例的特征进行结合和组合。
上述实施例只是为了说明本发明的技术构思及特点，其目的是在于让本领域内的普通技术人员能够了解本发明的内容并据以实施，并不能以此限制本发明的保护范围。凡是根据本发明内容的实质所做出的等效的变化或修饰，都应涵盖在本发明的保护范围内。

Claims (10)

  1. 一种800kV柔性直流穿墙套管，包括套筒和设置在所述套筒内的电容芯子，其特征在于，所述800kV柔性直流穿墙套管还包括第一法兰、户外复合绝缘子、户内复合绝缘子、载流导体和铝卷制管；
    所述第一法兰设置在所述套筒上，所述第一法兰把所述套筒分成户外段和户内段；所述户外复合绝缘子和所述户内复合绝缘子通过所述第一法兰分别固定套设在所述套筒的户外段和户内段；
    所述载流导体穿过所述铝卷制管并与所述铝卷制管同轴间隔设置，所述载流导体具有户外端部和户内端部，所述载流导体的户外端部和户内端部穿过所述铝卷制管并分别穿出所述套筒的户外段远离所述第一法兰的第一端部和所述套筒的户内段远离所述第一法兰的第二端部；所述铝卷制管的两端均与所述载流导体连接；
    所述电容芯子包括多层胶浸纸和多层电容屏，所述多层胶浸纸和多层电容屏依次交替绕设在所述铝卷制管上；所述多层电容屏包括沿径向从内到外的首层电容屏、中间电容屏和末层电容屏，其中，所述中间电容屏与所述末层电容屏的轴向长度比值，与，所述中间电容屏与所述末层电容屏之间的径向厚度比值的2倍相差预设阈值。
  2. 根据权利要求1所述的800kV柔性直流穿墙套管，其特征在于，所述预设阈值的范围为0cm-2cm。
  3. 根据权利要求1所述800kV柔性直流穿墙套管，其特征在于，所述800kV柔性直流穿墙套管还包括户外端部结构和户内端部结构，所述户外端部结构设置在所述套筒的第一端部处，所述户内端部结构设置在所述套筒的第二端部处，以分别对所述载流导体的户外端部和所述套筒的第一端部、以及所述载流导体的户内端部和所述套筒的第二端部进行密封。
  4. 根据权利要求3所述的800kV柔性直流穿墙套管，其特征在于，所述户内端部结构包括第一端盖板、弹簧压缩结构、第一将军帽和第一顶盖；
    所述弹簧压缩结构包括呈圆筒状的弹簧座、弹簧压板和若干弹簧组件；
    所述弹簧座的上端部具有向外周延伸的第一外凸缘，所述弹簧座的下端部具有向内周延伸的第二内凸缘，所述第二内凸缘上设置有若干沿圆周分布的第一开孔；
    所述弹簧压板呈圆形状并匹配设置在呈圆筒状的弹簧座内，所述弹簧压板上设置有供所述载流导杆穿过的第一开口和与所述第一开孔匹配的若干第二开孔；
    每一所述弹簧组件均包括弹簧导杆、导杆螺母、弹簧、弹簧压头和定心螺母；每一所述弹簧设置在所述弹簧座的第二内凸缘和所述弹簧压板之间，每一所述弹簧导杆依次穿过所述导杆螺母、所述弹簧压板的第一开孔、所述弹簧压头、所述弹簧、所述定心螺母和所述第二开孔，以将所述弹簧固定在所述弹簧座的第二内凸缘和所述弹簧压板之间；
    所述第一端盖板设置有供所述载流导杆穿过的第二开口和供所述弹簧座的第一外凸缘安装的凹槽，所述第一端盖板密封设置在所述套筒的第二端部上；
    所述第一将军帽设置有与所述载流导杆的户内端部相适配的第一内腔和设置在所述第一内腔的外周面的第三外凸缘；
    所述第一顶盖设置有供所述载流导杆穿过的第三开口，所述第一顶盖设置在所述第一将军帽的第三外凸缘与所述第一端盖板之间，以实现所述第一将军帽与所述第一端盖板以及所述弹簧座之间的密封；
    所述载流导杆的户内端部依次穿过所述弹簧座的下端部、所述弹簧压板的第一开口、所述弹簧座的上端部、所述第一端盖板的第二开口、所述第一顶盖第三开口并位于所述第一将军帽的第一内腔中。
  5. 根据权利要求4所述的800kV柔性直流穿墙套管，其特征在于，所述户内端部结构还包括承压板、第一载流单元、户内端法兰盘、户内端部均压装置和若干密封圈；
    所述承压板位于所述弹簧压板的上方并套接在所述载流导杆上；所述第一载流单元设置在所述第一将军帽的第一内腔的内圆周表面和所述载流导杆之间；所述第一载流单元包括第一上限位卡圈、第一下限位卡圈和设置在所述第一上限位卡圈和第一下限位卡圈之间的第一表带触指；
    所述户内端法兰盘套设在所述套筒的第二端部的外周并与所述第一端盖板可拆卸固定连接，以将所述第一端盖板固定在所述套筒的第二端部上；
    所述户内端部均压装置位于在所述弹簧压缩结构和所述套筒之间；
    所述若干密封圈包括第一平面密封圈、第二平面密封圈、第三平面密封圈、第四平面密封圈和第一轴向密封圈；
    所述第一平面密封圈设置在所述第一将军帽与所述第一顶盖之间，所述第二平面密封圈设置在所述第一顶盖与所述第一端盖板之间，所述第三平面密封圈设置在所述第一端盖板与所述弹簧压缩结构的弹簧座的连接处，所述第四平面密封圈设置在所述户内端部法兰盘与所述第一端盖板之间，所述第一轴向密封圈设置在所述载流导体与所述第一顶盖之间。
  6. 根据权利要求3所述的800kV柔性直流穿墙套管，其特征在于，所述户外端部结构包括第二端盖板、第二将军帽、第二顶盖和第二载流结构；
    所述第二端盖板设置有供所述载流导杆穿过的第四开口；
    所述第二将军帽设置有与所述载流导杆的户外端部相适配的第二内腔和设置在所述第二内腔的外周面的第四外凸缘；
    所述第二顶盖设置有供所述载流导杆穿过的第五开口，所述第二顶盖设置在所述第二将军帽的第四外凸缘与所述第二端盖板之间，以实现所述第二将军帽与所述第二端盖板之间的密封；
    所述载流导杆的户外端部依次穿过第二端盖板的第四开口、所述第二端盖板的第五开口并位于所述第二将军帽的第二内腔中。
  7. 根据权利要求6所述的800kV柔性直流穿墙套管，其特征在于，所述户外端部结构还包括第二载流 单元、户外端法兰盘、户外端部均压装置、第五平面密封圈、第六平面密封圈、第七平面密封圈和第二轴向密封圈；
    所述第二载流单元设置在所述第二将军帽的第二内腔的内圆周表面和所述载流导杆之间；所述第二载流单元包括第二上限位卡圈、第二下限位卡圈和设置在所述第二上限位卡圈和第二下限位卡圈之间的第二表带触指；
    所述户外端法兰盘套设在所述套筒的第一端部的外周并与所述第二端盖板可拆卸固定连接，以将所述第二端盖板固定在所述套筒的第一端部上；
    所述户外端部均压装置位于在所述载流导杆和所述套筒之间；
    所述第五平面密封圈设置在所述第二将军帽与所述第二端盖板之间，所述第六平面密封圈设置在所述第二顶盖与所述第二端盖板之间，所述第七平面密封圈设置在所述套管的户外端部法兰盘与所述第二端盖板之间；所述第二轴向密封圈设置在所述载流导体与所述第二顶盖之间。
  8. 根据权利要求1所述的800kV柔性直流穿墙套管，其特征在于，所述800kV柔性直流穿墙套管包括第一导电件和第一绝缘件，所述铝卷制管的一端通过所述第一导电件与所述载流导体等电位连接，所述铝卷制管的另一端通过所述第一绝缘件与所述载流导体绝缘连接，所述铝卷制管和所述载流导体之间设置有绝缘介质。
  9. 根据权利要求1所述的800kV柔性直流穿墙套管，其特征在于，所述800kV柔性直流穿墙套管还包括第一均压装置、第二均压装置、第一均压环和第二均压环，所述第一均压装置和所述第二均压装置分别设置在所述铝卷制管与所述载流导体的两个连接处；所述800kV柔性直流穿墙套管还包括第一均压环和第二均压环，所述第一均压环设置在所述套筒的第一端部，所述第二均压环设置在所述套筒的第二端部。
  10. 根据权利要求1所述的800kV柔性直流穿墙套管，其特征在于，所述套筒的户外段和户内段为非对称结构，位于所述户外段内的电容芯子的长度大于位于所述户内段的电容芯子的长度。
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117559233A (zh) * 2024-01-10 2024-02-13 四川众信通用电力有限公司 一种接线方便的绝缘开关柜

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115346775B (zh) * 2022-09-15 2024-09-06 广东电网有限责任公司东莞供电局 一种新型主变高压套管将军帽

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN204290209U (zh) * 2014-11-06 2015-04-22 中国西电电气股份有限公司 一种对接式交直流穿墙套管
CN105703293A (zh) * 2016-03-17 2016-06-22 苏州翰为电气科技有限公司 一种环氧树脂干式穿墙套管
WO2018032716A1 (zh) * 2016-08-15 2018-02-22 江苏智达高压电气有限公司 一种特高压sf6气体绝缘穿墙套管
WO2018036082A1 (zh) * 2016-08-22 2018-03-01 江苏智达高压电气有限公司 一种特高压直流穿墙套管
CN107768118A (zh) * 2017-12-18 2018-03-06 蒋秋菊 电容式变压器瓷伞裙套管
CN109494028A (zh) * 2018-12-05 2019-03-19 西安西电高压套管有限公司 单导管结构油纸套管
CN109817395A (zh) * 2019-03-11 2019-05-28 江苏神马电力股份有限公司 电容芯子、变压器套管以及电容芯子的制备方法
CN209592892U (zh) * 2019-05-08 2019-11-05 佘振球 导电管散热式穿墙套管
CN110504092A (zh) * 2019-09-10 2019-11-26 Abb瑞士股份有限公司 套管及其制造方法
CN111599574A (zh) * 2020-05-27 2020-08-28 宿松恒达电气配件有限公司 一种套管用油枕及其加工工艺
CN112489901A (zh) * 2020-11-27 2021-03-12 中国南方电网有限责任公司超高压输电公司检修试验中心 一种用于直流穿墙套管用末屏引出装置
CN112735702A (zh) * 2020-12-03 2021-04-30 全球能源互联网研究院有限公司 基于低电导温度系数环氧复合材料的直流套管均压装置

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4430692B2 (ja) * 2007-06-22 2010-03-10 昭和電線ケーブルシステム株式会社 ポリマー套管およびこれを用いたケーブル終端接続部
CN103500967A (zh) * 2013-10-22 2014-01-08 国家电网公司 胶浸纸电容式特高压交直流穿墙套管
CN104362565A (zh) * 2014-11-06 2015-02-18 中国西电电气股份有限公司 一种特高压胶浸纸电容式穿墙套管

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN204290209U (zh) * 2014-11-06 2015-04-22 中国西电电气股份有限公司 一种对接式交直流穿墙套管
CN105703293A (zh) * 2016-03-17 2016-06-22 苏州翰为电气科技有限公司 一种环氧树脂干式穿墙套管
WO2018032716A1 (zh) * 2016-08-15 2018-02-22 江苏智达高压电气有限公司 一种特高压sf6气体绝缘穿墙套管
WO2018036082A1 (zh) * 2016-08-22 2018-03-01 江苏智达高压电气有限公司 一种特高压直流穿墙套管
CN107768118A (zh) * 2017-12-18 2018-03-06 蒋秋菊 电容式变压器瓷伞裙套管
CN109494028A (zh) * 2018-12-05 2019-03-19 西安西电高压套管有限公司 单导管结构油纸套管
CN109817395A (zh) * 2019-03-11 2019-05-28 江苏神马电力股份有限公司 电容芯子、变压器套管以及电容芯子的制备方法
CN209592892U (zh) * 2019-05-08 2019-11-05 佘振球 导电管散热式穿墙套管
CN110504092A (zh) * 2019-09-10 2019-11-26 Abb瑞士股份有限公司 套管及其制造方法
CN111599574A (zh) * 2020-05-27 2020-08-28 宿松恒达电气配件有限公司 一种套管用油枕及其加工工艺
CN112489901A (zh) * 2020-11-27 2021-03-12 中国南方电网有限责任公司超高压输电公司检修试验中心 一种用于直流穿墙套管用末屏引出装置
CN112735702A (zh) * 2020-12-03 2021-04-30 全球能源互联网研究院有限公司 基于低电导温度系数环氧复合材料的直流套管均压装置

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117559233A (zh) * 2024-01-10 2024-02-13 四川众信通用电力有限公司 一种接线方便的绝缘开关柜
CN117559233B (zh) * 2024-01-10 2024-03-22 四川众信通用电力有限公司 一种接线方便的绝缘开关柜

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