Multi-loop gil terminal arrangement and gil power transmission system

Abstract

The application relates to a multi-loop GIL terminal arrangement structure, which comprises a first GIL phase assembly and two second GIL phase assemblies, the two second GIL phase assemblies are oppositely and spacedly arranged, and the first GIL phase assembly is located between the two second GIL phase assemblies. The first GIL phase assembly comprises a first GIL device and a single-phase common bus, the single-phase common bus is connected with the first GIL device, and the single-phase common bus extends along the spacing direction of the two second GIL phase assemblies. The second GIL phase assembly comprises a terminal framework, a plurality of second GIL devices, a plurality of overhead conductors and a plurality of connecting lines, the terminal frameworks of the two second GIL phase assemblies are arranged on the two sides of the single-phase common bus, the plurality of overhead conductors are arranged on the terminal framework along the extension direction of the single-phase common bus, and the plurality of connecting lines are used for connecting the plurality of overhead conductors with the plurality of second GIL devices. When any second GIL device fails, the connecting line connected with the second GIL device can be connected to the single-phase common bus, so that the efficient and intensive configuration of the GIL terminal arrangement structure is realized.

Description

Technical Field

[0001] This application relates to the field of GIL power transmission technology, and in particular to a multi-circuit GIL terminal arrangement structure and a GIL power transmission system. Background Technology

[0002] With the continuous advancement of ultra-high voltage and extra-high voltage power grid construction and the accelerating pace of urbanization in my country, the contradiction between power transmission channels and land resources is becoming increasingly prominent. In some urban areas, ecological protection zones, and special geographical environments, traditional overhead transmission lines are limited by construction conditions and cannot meet the needs of line construction; while conventional cable lines are limited in applicability in some large-capacity transmission scenarios due to factors such as transmission capacity. GIL (Gas Insulated Metal-Enclosed Transmission Line), as a type of high-voltage transmission equipment using gas insulation, has the characteristics of large transmission capacity and strong adaptability to operating environment, and is therefore gradually being applied in the undergrounding of overhead lines and the connection projects between overhead lines and underground transmission lines.

[0003] In related technologies, when connecting overhead lines to GIL (Gas-Insulated Line) lines, a GIL terminal field is typically required. This field houses GIL terminal equipment, surge arresters, terminal frames, and overhead conductor connection equipment. The GIL terminal field is generally configured according to the transmission line circuit to achieve the electrical connection between the overhead line and the GIL line. To improve the operational reliability of the transmission line, backup phase equipment is usually configured to take over operation in the event of a line fault.

[0004] However, with the development of transmission lines towards multi-circuit configurations, the number of terminal fields and spare phase equipment has increased accordingly, making the overall layout of terminal fields and spare phases more complex, and also increasing the scale of engineering construction and investment costs. In related technologies, the terminal fields and spare phases of multi-circuit GIL lines are usually configured relatively independently, and there is still room for further optimization in engineering construction. Therefore, how to achieve a reasonable configuration of terminal fields and spare phase equipment has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] Based on this, this application provides a multi-circuit GIL terminal arrangement structure and a GIL transmission system to solve the problem that the configuration of operating GIL phase components and GIL phase components used for fault replacement in the relevant GIL terminal arrangement structure is not compact enough.

[0006] This application provides a multi-loop GIL terminal arrangement structure, the GIL terminal arrangement structure includes a first GIL phase component and two second GIL phase components, the two second GIL phase components are arranged opposite to each other and spaced apart, and the first GIL phase component is located between the two second GIL phase components;

[0007] The first GIL phase assembly includes a first GIL device and a single-phase common busbar, the single-phase common busbar being connected to the first GIL device and extending along the interval direction between the two second GIL phase assemblies;

[0008] The second GIL phase assembly includes a terminal frame, multiple second GIL devices, multiple overhead conductors, and multiple connecting lines. The terminal frames of the two second GIL phase assemblies are arranged on both sides of the single-phase common bus. The multiple overhead conductors are arranged along the extension direction of the single-phase common bus and connected to the terminal frame. The multiple connecting lines are used to connect the multiple overhead conductors to the multiple second GIL devices. When any second GIL device fails, the connecting line connected to the failed second GIL device can be reconnected to the single-phase common bus.

[0009] In one embodiment, the first GIL phase assembly further includes a support member disposed between the terminal frames of the two second GIL phase assemblies, the support member being used to suspend the single-phase common busbar.

[0010] In one embodiment, the supporting member includes a plurality of post insulators arranged at intervals. The single-phase common busbar includes a rigid conduit busbar and a regulating conductor. The rigid conduit busbar extends and connects between each of the post insulators. One end of the regulating conductor is connected to the rigid conduit busbar frame, and the other end is connected to the first GIL device.

[0011] In one embodiment, each of the second GIL phase components further includes a plurality of down conductors and a plurality of surge arresters, the plurality of down conductors and the plurality of surge arresters corresponding one-to-one with a plurality of overhead conductors, one end of the down conductor being connected to the overhead conductor and the other end being connected to the surge arrester, the plurality of surge arresters being arranged at intervals along the extension direction of the rigid busbar and respectively connected to a plurality of connecting lines.

[0012] In one embodiment, the terminal frame is provided with multiple overlapping crossarms and multiple overlapping jumpers. Each of the multiple overlapping crossarms and multiple overlapping jumpers corresponds to a down conductor. One end of each overlapping jumper is connected to the overhead conductor, and the other end is connected to the overlapping crossarm and then to the down conductor.

[0013] In one embodiment, the height of the lap crossarm is lower than the height of the overhead conductor, and the height of the post insulator is lower than or equal to the height of the lap crossarm.

[0014] In one embodiment, the second GIL device is located on the side of the terminal frame away from the single-phase common busbar. The second GIL device includes a GIL main terminal bushing and a GIL main body. The GIL main terminal bushing is correspondingly arranged with the surge arrester. The GIL main bushing and the surge arrester are arranged on both sides of the terminal frame, and the surge arrester is located on the side of the terminal frame closer to the rigid busbar. A plurality of GIL main bodies extend along the arrangement direction of the plurality of GIL main terminal bushings and are arranged on the outside of the GIL main terminal bushing. One end of the GIL main terminal bushing is connected to the GIL main body, and the other end is connected to the surge arrester through the connecting line.

[0015] In one embodiment, the extension length of the rigid busbar is L, and the length of the section formed by the arrangement of multiple surge arresters of each second GIL phase assembly is D, wherein 0.75D≤L≤D.

[0016] In one embodiment, the terminal structures of the two second GIL phase components are respectively provided with six overhead conductors, all of which are located in the same plane and form four three-phase feed circuits.

[0017] On the other hand, this application also provides a GIL power transmission system, including the GIL terminal arrangement structure described in any of the foregoing embodiments, as well as a terminal working well and a status monitoring device. The first GIL device and the second GIL device are both disposed in the terminal working well. The status monitoring device is electrically connected to the first GIL device and the second GIL device respectively, and is used to monitor the operating status of the first GIL device and the second GIL device respectively.

[0018] This application discloses a multi-circuit GIL terminal arrangement structure and a GIL transmission system, which have the following advantages compared with related technologies:

[0019] This application extends the single-phase common busbar in the first GIL phase assembly along the interval between the two second GIL phase assemblies, and arranges multiple overhead conductors along the extension direction of the single-phase common busbar in the terminal frame on both sides, thereby including all overhead conductors within the electrical coverage of the single-phase common busbar. Under normal operating conditions, multiple overhead conductors can be connected to their respective second GIL devices via corresponding connecting lines. When any second GIL device malfunctions, simply disconnect the connecting line corresponding to the malfunctioning second GIL device from the faulty device and then reconnect it to the single-phase common busbar. The busbar allows the faulty phase overhead conductor to be switched to the backup first GIL device via this single-phase common busbar. Only one set of first GIL devices is needed to replace the backup second GIL devices in the two second GIL phase components on both sides. This avoids the redundant investment in equipment caused by setting up a backup phase for each circuit, and eliminates the need for complex switching devices. As a result, it significantly reduces the number of backup devices and the floor space occupied by the terminal, while achieving a highly efficient and compact configuration of the GIL terminal layout structure. It can also quickly establish a backup transmission path after a fault occurs, improving the efficiency of power restoration and the continuity of power supply. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the multi-loop GIL terminal arrangement structure provided in this application embodiment under normal operating conditions at one angle.

[0021] Figure 2 for Figure 1 The diagram shows a multi-loop GIL terminal arrangement structure at one angle in the standby phase switching state.

[0022] Figure 3 This is a schematic diagram of the multi-loop GIL terminal arrangement structure provided in the embodiments of this application under normal operating conditions from another angle.

[0023] Figure 4 for Figure 3 The diagram shows another angle of the multi-loop GIL terminal arrangement structure in the standby phase switching state.

[0024] Figure 5 This is a schematic diagram of the structure of the first GIL phase component in the multi-loop GIL terminal arrangement structure provided in the embodiments of this application.

[0025] Figure 6 This is a schematic diagram of the structure of the first GIL phase component in the multi-loop GIL terminal arrangement structure provided in the embodiments of this application.

[0026] In the diagram, 1. GIL terminal layout structure; 10. First GIL phase assembly; 11. Single-phase common busbar; 111. Hard conduit busbar; 112. Adjusting conductor; 12. Supporting component; 13. First GIL equipment; 131. GIL spare terminal bushing; 132. GIL spare pipe body; 20. Second GIL phase assembly; 21. Terminal frame; 22. Overhead conductor; 23. Second GIL equipment; 231. GIL main terminal bushing; 232. GIL main pipe body; 24. Connecting line; 25. Down conductor; 26. Surge arrester; 27. Overlapping crossarm; 28. Overlapping jumper; 29. ​​Lightning protection wire; 2. Terminal working well. Detailed Implementation

[0027] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0028] In the description of this application, it should be understood that the terms "height", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and 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, and therefore should not be construed as a limitation of this application.

[0029] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0030] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0031] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0032] For ease of explanation, let's define the terminology used in this paper: The term "circuit" as used herein refers to a complete transmission circuit consisting of three lines: phase A, phase B, and phase C. Typically, a double-circuit GIL transmission project is configured with one GIL terminal field, containing two sets of three-phase lines (A, B, and C); a four-circuit GIL transmission project is configured with two GIL terminal fields, each containing two sets of three-phase lines (A, B, and C). In relevant GIL transmission projects, the corresponding GIL terminal fields and related equipment are generally configured according to the number of transmission circuits. However, to ensure the continuous operation of the transmission system during line faults, some projects include spare phases to replace the faulty phase during a fault. A common configuration for spare phases is to set up a corresponding number of spare phases for each different circuit.

[0033] Furthermore, the term "multi-circuit" as used in this document refers to a GIL transmission system consisting of three or more transmission circuits. Since such systems often employ a dual-circuit modular configuration, even-numbered circuit configurations such as four, six, and eight circuits are common, with four-circuit projects being the most prevalent. However, in some engineering scenarios, there may be transmission requirements with three, five, or other circuits, and the configuration of terminal equipment will be adjusted accordingly based on specific engineering conditions. The aforementioned dual-circuit and four-circuit configurations are merely examples for understanding the technical solution of this application and do not constitute a limitation on the number of circuits applicable to this application. In practical applications, this application is also applicable to six-circuit, eight-circuit, and other multi-circuit GIL transmission projects.

[0034] See Figures 1 to 3 An embodiment of this application provides a multi-loop GIL terminal arrangement structure. The GIL terminal arrangement structure 1 includes a first GIL phase component 10 and two second GIL phase components 20. The two second GIL phase components 20 are arranged opposite to each other and spaced apart. The first GIL phase component 10 is located between the two second GIL phase components 20.

[0035] The first GIL phase assembly 10 includes a first GIL device 13 and a single-phase common bus 11. The single-phase common bus 11 is connected to the first GIL device 13 and extends along the interval direction between the two second GIL phase assemblies 20.

[0036] The second GIL phase assembly 20 includes a terminal frame 21, multiple second GIL devices 23, multiple overhead conductors 22, and multiple connecting lines 24. The terminal frames 21 of the two second GIL phase assemblies 20 are arranged on both sides of the single-phase common bus 11. The multiple overhead conductors 22 are arranged along the extension direction of the single-phase common bus 11 and connected to the terminal frame 21. The multiple connecting lines 24 are used to connect the multiple overhead conductors 22 to the multiple second GIL devices 23 respectively. When any second GIL device 23 fails, the connecting line 24 connected to the failed second GIL device 23 can be reconnected to the single-phase common bus 11.

[0037] This application extends the single-phase common busbar 11 in the first GIL phase assembly 10 along the interval between the two second GIL phase assemblies 20, and arranges multiple overhead conductors 22 along the extension direction of the single-phase common busbar 11 on the terminal frame 21 on both sides, thereby including all overhead conductors 22 within the electrical coverage of the single-phase common busbar 11. Under normal operating conditions, multiple overhead conductors 22 can be connected to the corresponding second GIL device 23 via corresponding connecting lines 24. When any second GIL device 23 fails, simply disconnect the corresponding connecting line 24 from the failed second GIL device 23 and then reconnect. By connecting to the single-phase common busbar 11, the faulty phase overhead conductor 22 can be switched to the backup first GIL device 13. Only one set of first GIL device 13 is needed to replace the multi-phase second GIL devices 23 in the two second GIL phase components 20 on both sides. This avoids the repeated investment in equipment caused by setting up a backup phase for each circuit, and eliminates the need to add complex switching devices. Thus, while significantly reducing the number of backup devices and the terminal area, it achieves a highly efficient and compact configuration of the GIL terminal layout structure, and can quickly establish a backup transmission path after a fault occurs, improving the efficiency of line power restoration and power supply continuity.

[0038] For ease of description, the second GIL phase assembly 20 referred to in this application refers to a set of equipment constituting a GIL terminal field main transmission circuit, including a terminal frame 21, overhead conductor 22, connecting line 24, GIL main terminal equipment, and related supporting equipment. In a dual-circuit embodiment, one second GIL phase assembly 20 corresponds to one dual-circuit GIL terminal field; in a four-circuit embodiment, one second GIL phase assembly 20 corresponds to two GIL terminal fields (i.e., each terminal field contains one second GIL phase assembly 20); in a six-circuit or more-circuit embodiment, following the same logic, each GIL terminal field corresponds to one second GIL phase assembly 20, and the number of circuits corresponds one-to-one with the number of terminal fields and the number of second GIL phase assemblies 20. It should be understood that the configuration forms of dual-circuit, four-circuit, and other circuit numbers in this application are merely illustrative examples. Based on the technical concept of this application, those skilled in the art can make adaptive adjustments or equivalent transformations to the number of terminal fields, equipment configuration and number of loops according to actual engineering needs. The resulting technical solutions should be regarded as realizing the technical concept of this application and achieving the corresponding technical effects, and all fall within the protection scope of this application.

[0039] In addition, in this embodiment, "reconnection" means that when any second GIL device 23 fails and is taken out of operation, the connecting line 24 that was originally electrically connected to the second GIL device 23 is disconnected from the failed second GIL device 23 and connected to the single-phase common bus 11, so that the corresponding overhead conductor 22 is electrically connected to the single-phase common bus 11 via the connecting line 24, so as to restore the power transmission path by using the first GIL device connected to the single-phase common bus 11, so that the first GIL device can replace the failed second GIL device 23 to continue to undertake the power transmission function.

[0040] It should be noted that the spacing direction between the two second GIL phase components 20, as referred to herein, refers to the extension direction of the spacing area formed between their adjacent sides when the two second GIL phase components 20 are arranged opposite each other. In other words, a space is usually reserved between the two second GIL phase components 20 for equipment layout, operation and maintenance, and safety insulation. The single-phase common busbar 11 is arranged within this space and extends along the length of the space, so that it can cover the corresponding connection positions in the two second GIL phase components 20, so that the second GIL device 23 of any faulty phase can be connected to the single-phase common busbar 11 through the corresponding connection line 24 to achieve a backup connection with the first GIL device 13. Of course, the specific width and shape of the spacing space can be adjusted according to the actual engineering layout. As long as the single-phase common busbar 11 is located between the two second GIL phase components 20 and extends along their spacing area, it falls within the scope of the "spacing direction" described in this application.

[0041] See Figures 1 to 3 In an optional embodiment of this application, the first GIL phase assembly 10 further includes a support member 12, which is disposed between the terminal frames 21 of the two second GIL phase assemblies 20. The support member 12 is used to provide an overhead single-phase common busbar 11.

[0042] Specifically, the single-phase common busbar 11 is supported above the ground by the support member 12, maintaining a predetermined insulation distance between the single-phase common busbar 11 and the ground and surrounding structures, thereby meeting the requirements of the power transmission system for electrical insulation and safety clearance. At the same time, the support member 12 can provide stable mechanical support for the single-phase common busbar 11, reducing the possibility of displacement or deformation caused by its own weight, wind load, and conductor electrodynamic forces, which helps to ensure the stability of the connection relationship between the single-phase common busbar 11 and each of the 24 connecting lines, and improves the reliability of the standby phase circuit operation.

[0043] In this application, the single-phase common busbar 11 can be any one of the following: rigid conduit busbar 111, rectangular busbar, channel busbar, or flexible conductor. Rigid conduit busbar 111 is preferred, as its main body is a tubular conductor, typically made of aluminum alloy or copper. It has high mechanical strength, strong current carrying capacity, and uniform surface electric field distribution, making it suitable for long-distance, high-current transmission scenarios. Furthermore, it can achieve large-span overhead layouts through post insulators, effectively reducing the number of supporting components 12. Rectangular busbars are also easy to process and have good heat dissipation performance, making them suitable for short-to-medium distance compact layouts. Channel busbars have the characteristics of low skin effect and high current carrying capacity per unit cross-section, making them suitable for short-distance, ultra-high-current scenarios. Flexible conductors are flexible and low-cost, making them suitable for scenarios with long spans. The type of single-phase common busbar 11 can be flexibly selected according to actual engineering needs, current carrying capacity requirements, and terminal space conditions, all of which can realize the function of connecting the overhead conductors 22 on both sides to the GIL backup terminal equipment via the common busbar. The above enumeration does not constitute an exhaustive limitation on the single-phase common busbar type 11 of this application. After reading this application, those skilled in the art can also select other applicable busbar types according to specific engineering conditions.

[0044] It should be noted that, for ease of understanding the technical solutions of this application, the term "operating GIL phase component" generally refers to a GIL phase component in normal transmission state that undertakes the main transmission task, and in some embodiments of this application, it may correspond to the second GIL phase component 20; the term "GIL phase component for fault replacement" generally refers to a GIL phase component used to replace an operating GIL phase component when it fails, and in some embodiments of this application, it may correspond to the first GIL phase component 10, used to replace the second GIL phase component 20 when it fails. Furthermore, the terms "primary phase" and "standby phase" mentioned herein are only used to facilitate the description of the functions undertaken by each GIL phase component under different operating states. The GIL phase component undertaking normal transmission task can be called the primary phase, corresponding to the operating GIL phase component; the GIL phase component used for replacement operation when the primary phase fails can be called the standby phase, corresponding to the GIL phase component used for fault replacement. In this application, the primary phase and the backup phase are functional definitions, and their specific structures are still based on the first GIL phase assembly 10 and the second GIL phase assembly 20.

[0045] See Figure 4 and Figure 5 In one optional embodiment of this application, the support member 12 includes a plurality of post insulators arranged at intervals, and the single-phase common busbar 11 includes a rigid busbar 111 and an adjusting conductor 112. The rigid busbar 111 extends and connects between each post insulator, and one end of the adjusting conductor 112 is connected to the rigid busbar 111 frame, and the other end is connected to the first GIL device 13.

[0046] Specifically, considering the high mechanical strength, large span, and good operational stability of the rigid busbar 111, it can balance current carrying capacity and structural support requirements under overhead layout conditions. Therefore, the single-phase common busbar 11 in this application preferably adopts a structure where the rigid busbar 111 is connected to the first GIL device 13 in conjunction with the regulating conductor 112. The regulating conductor 112 preferably uses a conductive connector with a certain degree of flexibility. By connecting the regulating conductor 112 to the rigid busbar 111, the adaptability of the connection between the single-phase common busbar 11 and each GIL terminal device can be improved. This allows a single spare phase to establish electrical connections with GIL terminal devices in different locations according to actual needs, thereby reducing the restrictions on equipment location and structural form imposed by the spare phase layout. This facilitates the shared configuration between the spare phase and multiple main phases, further improving the utilization rate of spare resources and the intensification level of the terminal field layout.

[0047] See Figure 3 and Figure 4In an optional embodiment of this application, each second GIL phase assembly 20 further includes a plurality of down conductors 25 and a plurality of surge arresters 26. The plurality of down conductors 25 and the plurality of surge arresters 26 correspond one-to-one with a plurality of overhead conductors 22. One end of the down conductor 25 is connected to the overhead conductor 22 and the other end is connected to the surge arrester 26. The plurality of surge arresters 26 are arranged at intervals along the extension direction of the rigid busbar 111 and are respectively connected to a plurality of connecting lines 24.

[0048] Specifically, by setting up a down conductor 25 and a surge arrester 26 between the overhead conductor 22 and the second GIL device 23, and connecting the surge arrester 26 to the corresponding connecting line 24, the second GIL device 23 can form a backup switching path with the first GIL device 13 through the corresponding connecting line 24. When any second GIL device 23 fails, the connecting line 24 between the surge arrester 26 and the corresponding second GIL device 23 can be disconnected, and the connecting line 24 can be connected to the single-phase common bus 11, thereby allowing the overhead conductor 22 corresponding to the fault to switch to operation of the first GIL device 13. While ensuring overvoltage protection, this connection method avoids the need to increase the number of devices required to configure an independent backup phase for each circuit, which is beneficial to improving the sharing between the first GIL device 13 and multiple second GIL devices 23, and improving the integration level of the multi-circuit GIL terminal layout structure 1.

[0049] Multiple surge arresters 26 are arranged at intervals along the extension direction of the rigid busbar 111, so that the down conductors 25 and connecting lines 24 corresponding to each surge arrester 26 can form an orderly spatial layout with the rigid busbar 111. This makes the electrical connection path between the overhead conductor 22, down conductors 25, surge arresters 26, connecting lines 24, and rigid busbar 111 more regular, reducing line crossings and detours. Through the above arrangement, the crossing and cross connections in the backup switching path can be reduced, the connection distance when the faulty phase is switched from the second GIL device 23 to the first GIL device 13 can be shortened, the complexity of the internal wiring layout of the terminal field can be reduced, the compactness and regularity of the equipment layout can be improved, and subsequent inspection and maintenance can be facilitated.

[0050] In addition, each terminal frame 21 is equipped with a lightning protection wire 29 at its top. The lightning protection wire 29 is connected to the grounding system to provide lightning protection for the overhead lines and the terminal frame 21. By installing the lightning protection wire 29 at the top of the terminal frame 21, a protection zone can be formed for the overhead conductor 22 and related equipment, reducing the impact of lightning overvoltage on the GIL terminal equipment and connection structure, and improving the overall safety and reliability of the GIL terminal field operation.

[0051] See Figure 3 and Figure 4In one optional embodiment of this application, the terminal frame 21 is provided with a plurality of overlapping crossarms 27 and a plurality of overlapping jumpers 28. The plurality of overlapping crossarms 27 and the plurality of overlapping jumpers 28 correspond one-to-one with the down conductors 25. One end of the overlapping jumper 28 is connected to the overhead conductor 22, and the other end is connected to the overlapping crossarm 27 and then connected to the down conductor 25.

[0052] Specifically, by setting multiple overlapping crossarms 27 and multiple overlapping jumpers 28 on the terminal frame 21 and connecting them one-to-one with the down conductors 25, a hierarchical transition connection structure is formed between the overhead conductor 22 and the down conductor 25. The overlapping jumpers 28 are used to achieve a flexible connection between the overhead conductor 22 and the overlapping crossarms 27, and the overlapping crossarms 27 are used to provide unified support and transition for multiple circuit connection points, thereby allowing the electrical connection to gradually transition from the overhead conductor 22 to the down conductor 25 and the subsequent surge arrester 26 circuit.

[0053] Meanwhile, by lapping the crossarm 27 to centrally arrange multiple connection points, the connection positions of each circuit down conductor 25 can be arranged regularly on the terminal frame 21, which is conducive to optimizing the introduction path of the overhead conductor 22, reducing line crossings and spatial interference, and improving the regularity and intensification of the electrical connection arrangement on the terminal frame 21.

[0054] See Figure 3 and Figure 4 In one optional embodiment of this application, the height of the lap crossarm 27 is lower than the height of the overhead conductor 22, and the height of the post insulator is lower than or equal to the height of the lap crossarm 27.

[0055] Specifically, through the aforementioned height difference arrangement, the overhead conductor 22, the overlapping crossarm 27, and the post insulator form a layered arrangement from high to low. This allows the overhead conductor 22 to transition downwards via the overlapping jumper 28 to the down conductor 25 and subsequent connection structures, reducing the space occupied between the overhead conductor 22 and the terminal equipment and optimizing the electrical connection path within the terminal frame 21. The post insulator is an insulating support component 12 used to support live conductors and achieve electrical insulation between them and the ground. Its lower end is fixed to the foundation, frame, or other support structure, while its upper end supports the rigid busbar 111, tubular conductors, or other conductive components, thereby maintaining the conductive components at a predetermined installation height and meeting the ground insulation distance requirements.

[0056] Meanwhile, the height of the post insulator matches the lap crossarm 27, ensuring that the single-phase common busbar 11 installed on it is within a reasonable height range. This satisfies the insulation distance requirements between the single-phase common busbar 11 and the ground, while avoiding excessive height of the single-phase common busbar 11 which would reduce the space utilization of the terminal area. This also improves the compactness of the arrangement between the spare phase components and the main phase components, further enhancing the overall integration level of the terminal area. Furthermore, the single-phase common busbar 11 is positioned at a height compatible with the connecting line 24, making the disassembly, assembly, and reconnection of the connecting line 24 more convenient. In the event of a fault, it facilitates rapid switching between the faulty phase and the spare phase, thereby shortening fault handling time and improving the efficiency of power restoration. It should be noted that the height referred to in this article is the vertical distance of the lap crossarm 27, the overhead conductor 22, and the post insulator relative to the installation foundation surface of this arrangement (usually the terminal area ground or equipment installation reference surface). The heights of the overhead conductor 22, the lap crossarm 27, and the post insulator are all measured using the same installation reference surface.

[0057] See Figure 4 and Figure 6 In one optional embodiment of this application, the second GIL device 23 is located on the side of the terminal frame 21 away from the single-phase common bus 11. The second GIL device 23 includes a GIL main terminal bushing 231 and a GIL main body 232. The GIL main terminal bushing 231 is correspondingly arranged with the surge arrester 26. The GIL main bushing and the surge arrester 26 are arranged on both sides of the terminal frame 21, and the surge arrester 26 is located on the side of the terminal frame closer to the hard tube bus 111. Multiple GIL main bodies 232 extend along the arrangement direction of multiple GIL main terminal bushings 231 and are arranged on the outside of the GIL main terminal bushing 231. One end of the GIL main terminal bushing 231 is connected to the GIL main body 232, and the other end is connected to the surge arrester 26 through the connecting line 24.

[0058] Specifically, by placing the surge arrester 26 on the side of the terminal frame 21 close to the hard tube busbar 111, and placing the GIL main terminal bushing 231 on the side of the terminal frame 21 away from the hard tube busbar 111, the surge arrester 26 and the GIL main terminal bushing 231 are arranged on both sides of the terminal frame 21, making full use of the space on both sides of the terminal frame 21 and avoiding local space congestion and equipment overlap. Meanwhile, multiple GIL main tubes 232 extend along the arrangement direction of multiple GIL main terminal bushings 231 and are set on the outside of the GIL main terminal bushings 231, so that the main circuit equipment of each phase forms a neatly arranged tube bundle area on the outside of the terminal frame 21, while the surge arresters 26 of each phase are centrally arranged on the inside of the terminal frame 21. This not only achieves a clear partition between the main circuit equipment and the protection equipment, but also provides sufficient working space and convenient wiring path for reconnecting the connection line 24 on the side of the surge arrester 26 to the hard tube busbar 111 in case of a fault. Thus, while reducing the overall footprint of the terminal field, it improves the intensification level of equipment layout and the convenience of operation and maintenance.

[0059] In addition, the first GIL device 13 includes a GIL spare terminal bushing 131 and a GIL spare conduit body 132. The GIL spare terminal bushing 131 and the GIL spare conduit body 132 are disposed between two terminal frames 21 and located at one end of the rigid conduit bus 111, with the GIL spare conduit body 132 gradually extending outward from the GIL spare terminal bushing 131. Through the aforementioned arrangement, the connection distance between the first GIL device 13 and the single-phase common bus 11 is further shortened, reducing the spare phase lead-in path and auxiliary connection structure.

[0060] It should be noted that the GIL main terminal bushing 231 and the GIL backup terminal bushing 131 are used to realize the electrical connection and insulation transition between the GIL main body 232 and the GIL backup body 132 and the external transmission line, respectively. They typically include connection ends for leading out the internal conductors and bushing structures for achieving gas insulation sealing. The GIL main body 232 and the GIL backup body 132 are used to gas-insulate and seal the internal conductors, forming a power transmission channel. In practical engineering applications, the GIL main terminal bushing 231 and the GIL backup terminal bushing 131 are installed in the GIL terminal field to realize the transfer between overhead lines and GIL lines. After being led out from the terminal field, the GIL main body 232 and the GIL backup body 132 can be extended to underground laying areas or other transmission paths according to the line laying requirements to achieve continuous power transmission.

[0061] See Figure 1 and Figure 2 In one optional embodiment of this application, the extension length of the rigid busbar 111 is L, and the length of the section formed by the multiple surge arresters 26 of each second GIL phase assembly 20 is D, wherein 0.75D≤L≤D.

[0062] Specifically, to ensure that the rigid busbar 111 can cover the access positions of multiple surge arresters 26, so that when any phase second GIL device 23 fails, it can be connected to the rigid busbar 111 through the corresponding connection line 24, the extension length L of the rigid busbar 111 should not be too small; at the same time, to avoid the rigid busbar 111 being too long, which would lead to increased material occupation and reduced terminal space utilization, the extension length L of the rigid busbar 111 should not exceed the length D of the access area formed by multiple surge arresters 26 along the arrangement direction.

[0063] Preferably, the extension length L of the rigid busbar 111 satisfies: 0.75D≤L≤D. For example, when the length D of the access area formed by multiple surge arresters 26 is 20 meters, the extension length L of the rigid busbar 111 can be selected as any value between 15 meters and 20 meters.

[0064] Where D represents the length of the access area formed by multiple surge arresters 26 on the same side along the arrangement direction, that is, the distance between the two surge arresters 26 at the outermost ends. For example, when multiple surge arresters 26 are arranged sequentially as the first surge arrester 26 to the fourth surge arrester 26, D is the spacing between the first surge arrester 26 and the fourth surge arrester 26. The extension length L of the rigid busbar 111 is the distance measured between the two ends of the rigid busbar 111 along the extension direction. Through the above length relationship, the rigid busbar 111 can cover the connection positions of each surge arrester 26 while maintaining a spatial arrangement that matches the two second GIL phase components 20. This facilitates the connection between the GIL spare terminal bushing 131 in the first GIL device 13 and the rigid busbar 111, and allows the GIL spare tube body 132 to be set in a reasonable position between the two terminal frames 21, reducing the space occupied by the single-phase common busbar 11 and the spare equipment, and achieving a compact arrangement of the main phase component and the spare phase component.

[0065] See Figure 1 and Figure 2 In one optional embodiment of this application, the terminal frame 21 of the two second GIL phase components 20 is provided with six overhead conductors 22, all overhead conductors 22 are located on the same plane, and all overhead conductors 22 form four three-phase power supply loops.

[0066] Specifically, the application prefers to arrange it in the form of a four-circuit GIL transmission project, that is, the terminal frame 21 of the two second GIL phase components 20 is respectively equipped with six overhead conductors 22, and the six overhead conductors 22 on each side together form two three-phase feeder circuits, and the two second GIL phase components 20 together form four three-phase feeder circuits.

[0067] For ease of understanding, the second GIL phase assembly 20 located on one side of the rigid busbar 111 is referred to as the first-side second GIL phase assembly 20, and the second GIL phase assembly 20 located on the other side is referred to as the second-side second GIL phase assembly 20.

[0068] The first-side second GIL phase assembly 20 includes six overhead conductors 22, denoted as A11, B11, C11 and A12, B12, C12 respectively; the second-side second GIL phase assembly 20 includes six overhead conductors 22, denoted as A21, B21, C21 and A22, B22, C22 respectively. All the above overhead conductors 22 are mounted on their respective terminal frames 21 and are arranged at intervals along the extension direction of the single-phase common busbar 11.

[0069] Specifically, A11, B11, and C11 together form the first three-phase feed circuit on the first side; A12, B12, and C12 together form the second three-phase feed circuit on the first side; A21, B21, and C21 together form the third three-phase feed circuit on the second side; and A22, B22, and C22 together form the fourth three-phase feed circuit on the second side. Thus, the two second GIL phase modules 20 form a total of four three-phase feed circuits.

[0070] Under normal operating conditions, each overhead conductor 22 is connected to the corresponding second GIL device 23 via a corresponding connecting line 24 to form four three-phase transmission circuits. When the standby phase switching state occurs, i.e., when any phase of any of the second GIL devices 23 fails, the connecting line 24 corresponding to the fault can be disconnected from the faulty second GIL device 23, and the disconnected connecting line 24 can be connected to the rigid busbar 111, so that the corresponding overhead conductor 22 is connected to the first GIL device 13 via the rigid busbar 111. Thus, the first GIL device 13 replaces the faulty phase to participate in power transmission operation, which can quickly establish a backup power transmission path after a fault occurs, improving the efficiency of line power restoration and power supply continuity.

[0071] It should be noted that the designations A11, A12, A21, A22, etc., mentioned above are only used to facilitate the description of the correspondence between different locations, different feeder circuits, and different phases, and do not constitute a limitation on the specific numbering, phase sequence arrangement, or quantity configuration of the overhead conductors 22. In actual engineering applications, as long as a corresponding three-phase feeder circuit can be formed and electrically connected to the first GIL device 13 or the second GIL device 23 through the corresponding connection structure, it is considered an implementation of the technical concept of this application.

[0072] See Figure 1 and Figure 2On the other hand, this application also provides a GIL power transmission system, including the GIL terminal arrangement structure 1 described in any of the foregoing embodiments, as well as the terminal working well 2 and the status monitoring device. The first GIL device 13 and the second GIL device 23 are both disposed in the terminal working well 2. The status monitoring device is electrically connected to the first GIL device 13 and the second GIL device 23 respectively, and is used to monitor the operating status of the first GIL device 13 and the second GIL device 23 respectively.

[0073] By setting up the terminal working well 2, the first GIL device 13 and the second GIL device 23 can be arranged in the connection area between the overhead line and the underground GIL line, which facilitates the extension of the main GIL pipe 232 and the spare GIL pipe 132 from the terminal field to the underground laying area, thereby realizing the continuous transition between the overhead transmission line and the underground GIL line.

[0074] Meanwhile, the first GIL device 13 and the second GIL device 23 are centrally located in the terminal working well 2, forming a centralized spatial arrangement between the main phase channel and the backup phase channel. This helps reduce the dispersed installation of GIL devices in the ground terminal area and lowers the complexity of the connection between the overhead structure and the underground transmission line. In the event of a fault switchover, the first GIL device 13 can be connected to the corresponding faulty phase through the single-phase common bus 11 to achieve backup phase operation, thereby improving the operational reliability and fault recovery efficiency of the multi-circuit GIL transmission system.

[0075] The specific type of condition monitoring device can be selected from relevant technologies based on actual engineering needs. This includes, but is not limited to, partial discharge monitoring units, gas condition monitoring units, temperature monitoring units, or combinations thereof. Specifically, the partial discharge monitoring unit includes at least one of a high-frequency current sensor, an ultrasonic sensor, an ultra-high frequency sensor, or a built-in fiber optic distributed acoustic wave sensor. The sensor is installed at the grounding bar of the GIL terminal bushing or the GIL main body to collect partial discharge signals. The gas condition monitoring unit includes a sulfur hexafluoride gas density sensor and / or a micro-moisture sensor to monitor the density and micro-moisture content of the insulating gas within the GIL main body. The temperature monitoring unit includes a distributed fiber optic temperature measurement device to monitor the temperature distribution within the GIL main body.

[0076] The status monitoring device acquires the operating status signals of the first GIL device 13 and the second GIL device 23 via electrical connection and transmits the signals to the monitoring platform. The monitoring platform determines the operating status of each phase GIL device based on the signals. When a fault is detected in any phase of the second GIL device 23, the platform outputs corresponding fault information so that maintenance personnel can reconnect the corresponding connection line 24 to the single-phase common bus 11. It should be noted that the specific form and structure of the electrical connection referred to in this application are not limited. Wired connections include, but are not limited to, shielded cables, optical cables, or data communication buses. Wireless connections include any of the following wireless communication modules: Bluetooth, WiFi, ZigBee, or LoRa. Any wired or wireless connection method that can realize the transmission of operating status signals between the status monitoring device and the GIL device can be flexibly selected according to the actual project situation and is within the protection scope of this application.

[0077] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0078] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A multi-loop GIL terminal arrangement structure, characterized in that, The GIL terminal arrangement structure includes a first GIL phase component and two second GIL phase components. The two second GIL phase components are arranged opposite to each other and spaced apart. The first GIL phase component is located between the two second GIL phase components. The first GIL phase assembly includes a first GIL device and a single-phase common busbar, the single-phase common busbar being connected to the first GIL device and extending along the interval direction between the two second GIL phase assemblies; The second GIL phase assembly includes a terminal frame, multiple second GIL devices, multiple overhead conductors, and multiple connecting lines. The terminal frames of the two second GIL phase assemblies are arranged on both sides of the single-phase common bus. The multiple overhead conductors are arranged along the extension direction of the single-phase common bus and connected to the terminal frame. The multiple connecting lines are used to connect the multiple overhead conductors to the multiple second GIL devices. When any second GIL device fails, the connecting line connected to the failed second GIL device can be reconnected to the single-phase common bus.

2. The multi-loop GIL terminal arrangement structure according to claim 1, characterized in that, The first GIL phase assembly further includes a support member disposed between the terminal frames of the two second GIL phase assemblies, and the support member is used to suspend the single-phase common busbar.

3. The multi-loop GIL terminal arrangement structure according to claim 2, characterized in that, The supporting structure includes multiple post insulators, which are arranged at intervals. The single-phase common busbar includes a rigid conduit busbar and an adjusting conductor. The rigid conduit busbar extends and connects between each of the post insulators. One end of the adjusting conductor is connected to the rigid conduit busbar frame, and the other end is connected to the first GIL device.

4. The multi-loop GIL terminal arrangement structure according to claim 3, characterized in that, Each of the second GIL phase components also includes multiple down conductors and multiple surge arresters, each of which corresponds to one of the multiple overhead conductors. One end of each down conductor is connected to the overhead conductor, and the other end is connected to the surge arrester. The multiple surge arresters are arranged at intervals along the extension direction of the rigid busbar and are connected to the multiple connecting lines respectively.

5. The multi-loop GIL terminal arrangement structure according to claim 4, characterized in that, The terminal structure is provided with multiple overlapping crossarms and multiple overlapping jumpers. Each of the multiple overlapping crossarms and multiple overlapping jumpers corresponds to a down conductor. One end of each overlapping jumper is connected to the overhead conductor, and the other end is connected to the overlapping crossarm and then to the down conductor.

6. The multi-loop GIL terminal arrangement structure according to claim 5, characterized in that, The height of the lap crossarm is lower than the height of the overhead conductor, and the height of the post insulator is lower than or equal to the height of the lap crossarm.

7. The multi-loop GIL terminal arrangement structure according to claim 4, characterized in that, The second GIL device is located on the side of the terminal frame away from the single-phase common busbar. The second GIL device includes a GIL main terminal bushing and a GIL main body. The GIL main terminal bushing is correspondingly arranged with the surge arrester. The GIL main bushing and the surge arrester are arranged on both sides of the terminal frame, and the surge arrester is located on the side of the terminal frame closer to the rigid busbar. Multiple GIL main bodies extend along the arrangement direction of multiple GIL main terminal bushings and are arranged on the outside of the GIL main terminal bushing. One end of the GIL main terminal bushing is connected to the GIL main body, and the other end is connected to the surge arrester through the connecting line.

8. The multi-loop GIL terminal arrangement structure according to claim 7, characterized in that, The extension length of the rigid busbar is L, and the length of the section formed by the arrangement of multiple surge arresters in each second GIL phase assembly is D, wherein 0.75D≤L≤D.

9. The multi-loop GIL terminal arrangement structure according to claim 1, characterized in that, The terminal structures of the two second GIL phase components are respectively provided with six overhead conductors, all of which are located on the same plane and form four three-phase feed circuits.

10. A GIL transmission system, characterized in that, The device includes the GIL terminal arrangement structure as described in any one of claims 1-9, as well as the terminal working well and the status monitoring device, wherein the first GIL device and the second GIL device are both disposed in the terminal working well, and the status monitoring device is electrically connected to the first GIL device and the second GIL device respectively, for monitoring the operating status of the first GIL device and the second GIL device respectively.

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