Double-fusion-tube type GIS (Gas Insulated Switchgear) voltage transformer

Abstract

The utility model relates to the technical field of manufacturing of voltage transformers, and provides a double-fusion-tube type GIS voltage transformer which comprises a shell, a fuse tube and a fuse tube. The primary side and the secondary side are respectively used for sensing primary side voltage and secondary side voltage; and the double-fusion-tube protection structure is an independent fusion tube protection structure arranged in the shell, comprises a first fusion tube and a second fusion tube which are arranged at the primary side end, and is used for coping with an overcurrent or short-circuit fault from the primary side, and one fusion tube is quickly fused to cut off a fault current. According to the utility model, the overcurrent and short-circuit protection capability of equipment is improved, and efficient operation and convenient maintenance of the equipment are realized through modular design and intelligent monitoring.

Description

Technical Field

[0001] The utility model relates to the technical field of voltage transformer manufacturing, in particular to a double-fuse tube voltage transformer suitable for GIS (gas insulated switchgear). Background Art

[0002] With the rapid development of power systems and the continuous growth of power demand, the reliability and safety of high-voltage power equipment are becoming increasingly important. Traditional voltage transformers in high-voltage power systems of 35kV and above usually face the following challenges:

[0003] 1. Large size and complex installation: Traditional voltage transformers are large and complex in structure, requiring a large space for installation. Furthermore, in high-voltage environments, the installation and wiring process is cumbersome and often requires specialized technicians, increasing the difficulty and cost of installation.

[0004] 2. Inconvenient and costly maintenance: Due to the complex structure of traditional voltage transformers and the stringent requirements of high-voltage environments, regular maintenance and inspections are complex and costly. Particularly in harsh environments, such as those with high humidity and dust, traditional voltage transformers are more prone to failure, requiring frequent maintenance and replacement.

[0005] 3. Inadequate overcurrent and short-circuit protection: Traditional voltage transformers often lack effective protection mechanisms against transient overcurrent and short-circuit conditions. Once a fault occurs, the fault current can cause severe damage to equipment and systems, leading to power outages and equipment damage, impacting the stability and safety of the power supply.

[0006] 4. Environmental impact and pollution: Traditional voltage transformers are often oil-immersed, which poses a risk of oil leakage and fire during operation, easily polluting the environment. Furthermore, the performance of traditional insulating media deteriorates under high voltage and high temperature environments, increasing the risk of equipment failure.

[0007] To address these issues, modern GIS (gas-insulated switchgear) technology has emerged. GIS equipment utilizes gases such as SF6 as an insulating medium, offering significant advantages such as high insulation performance, compact structure, low maintenance requirements, and environmental friendliness. SF6 gas possesses excellent insulation and arc-extinguishing capabilities, effectively isolating electric fields in high-voltage environments, preventing arc discharges and ensuring safe and stable operation of the equipment. Through gas insulation, GIS equipment enables the installation and operation of high-voltage power equipment in a smaller space, reducing floor space and simplifying the installation process. The sealed design and gas insulation of GIS equipment significantly minimize the impact of the external environment on the equipment, extending its service life and reducing the frequency and cost of maintenance and overhaul. Compared to traditional oil-immersed voltage transformers, GIS equipment uses SF6 gas or its alternatives as an insulating medium, reducing environmental pollution and fire risks, thus meeting modern environmental protection requirements.

[0008] However, existing GIS voltage transformers still have some shortcomings. In particular, when dealing with overcurrent and short-circuit faults, the single-fuse design has a relatively simple protection mechanism and cannot fully prevent the spread of faults and equipment damage. Therefore, it is particularly important and necessary to propose a GIS voltage transformer with a dual-fuse protection structure to further improve the safety and reliability of the equipment. Utility Model Content

[0009] In response to the shortcomings of traditional voltage transformers and combining the advantages of GIS technology, this utility model provides a double-fuse voltage transformer suitable for GIS. It not only improves the overcurrent and short-circuit protection capabilities of the equipment, but also achieves efficient operation and convenient maintenance of the equipment through modular design and intelligent monitoring, providing a more advanced and reliable solution for modern power systems.

[0010] In order to solve the above technical problems, the present invention is achieved through the following technical solutions:

[0011] The utility model provides a double-fuse GIS voltage transformer, which is arranged in a gas-insulated switchgear and includes:

[0012] The housing has good sealing properties to prevent SF6 gas leakage and can also withstand the pressure of SF6 gas;

[0013] The primary side and secondary side are used for sensing the primary side and secondary side voltages respectively;

[0014] The double-melting tube protection structure is an independent melting tube protection structure arranged in the shell, comprising a first melting tube and a second melting tube arranged at the primary side end.

[0015] As a further solution of the present invention, the shell is a fully sealed shell structure made of stainless steel or aluminum alloy material through seamless welding.

[0016] As a further solution of the present invention, a heat sink is provided on the shell, a shock-absorbing pad and a shock-absorbing structure are provided inside the shell, and a base plate for ground installation and suspension installation is connected to the bottom of the shell.

[0017] As a further solution of the present invention, a gas circulation channel and a solid insulating member located in the gas circulation channel are further provided in the shell.

[0018] As a further solution of the present invention, the solid insulating member is a ceramic insulator or a silicone rubber insulating member arranged in the shell, and the solid insulating member is arranged in a spiral shape.

[0019] As a further solution of the present invention, the primary side and the secondary side are both arranged in layers along the axial direction with copper wires and wound on the iron core. The copper wires wound on the iron core are formed into a wire package wound on the iron core through pre-winding, intermediate layers and final winding. The wire package is a fully insulated wire package. The fully insulated wire package is wound with a primary wire on both sides. The wire package winding is designed in a slot shape, and the middle groove is the insulation distance reserved for resin casting.

[0020] As a further solution of the present invention, current sensors and temperature sensors are integrated inside the primary side and the secondary side, cooling ducts are also provided inside the primary side and the secondary side, and air ducts are provided inside the winding structure.

[0021] As a further solution of the present invention, the first melting tube and the second melting tube of the double melting tube protection structure both include a plug cover arranged at one end of the voltage transformer housing, a fuse retaining ring arranged inside the voltage transformer and abutting the plug cover and the melting tube, and an electrode mesh is provided on the melting tube, the electrode mesh is connected to the electrode, and the electrode is connected to the inner cone head arranged at the other end of the voltage transformer housing.

[0022] As a further solution of the present invention, the electrode networks of the first melting tube and the second melting tube are connected to the primary side coil, and the secondary side winding outlet terminal is led out from the bottom of the voltage transformer housing.

[0023] Compared with the prior art, the double-fuse GIS voltage transformer provided by the present invention has the following beneficial effects:

[0024] 1. A dual protection mechanism enhances system safety. Dual fuses on the primary side of the voltage transformer provide dual overcurrent and short-circuit protection. Even in the event of a fault, the fuse on one end continues to protect the system, preventing further damage. The fuse responds to overcurrent and short-circuit conditions within milliseconds, quickly shutting off the fault current and preventing impact on equipment and the power grid.

[0025] 2. High insulation and a fully enclosed design improve equipment reliability, extend service life, and reduce maintenance costs. This double-fuse GIS voltage transformer uses SF6 gas or other environmentally friendly insulating gases as the insulating medium, achieving complete sealing inside the device, preventing the impact of the external environment on the equipment and reducing the failure rate. SF6 gas has excellent insulation and arc extinguishing capabilities, enabling long-term stable operation in high-voltage environments, ensuring equipment reliability. The use of SF6 gas or environmentally friendly insulating gas effectively reduces the aging rate of internal components of the equipment, extending the service life of the equipment. The fully enclosed design and high-quality insulating materials make the equipment less susceptible to external environmental influences, reducing maintenance frequency and costs.

[0026] In summary, the double-fuse GIS voltage transformer of the utility model significantly improves the safety, reliability and maintainability of the equipment through its dual protection mechanism, high insulation performance and the use of environmentally friendly gases, extends its service life and reduces operating costs, providing a more advanced and comprehensive solution for the power system. It is widely used in urban power grids, industrial power supply, rail transportation and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 This is a schematic diagram of the overall structure of the double-fuse GIS voltage transformer with a transversely arranged inner cone head;

[0029] Figure 2 for Figure 1 A side perspective diagram of a double-fuse GIS voltage transformer of the present invention;

[0030] Figure 3 This is a schematic diagram of the overall structure of a double-fuse GIS voltage transformer with TYPE C installed horizontally in the present utility model;

[0031] Figure 4 for Figure 3 A side perspective diagram of a double-fuse GIS voltage transformer of the present invention;

[0032] Figure 5 This is a schematic diagram of the overall structure of the double-fuse GIS voltage transformer with a longitudinally arranged inner cone head;

[0033] Figure 6 for Figure 5 A side perspective diagram of a double-fuse GIS voltage transformer of the present invention;

[0034] Figure 7 This is a schematic diagram of the overall structure of the double-fuse GIS voltage transformer of the present invention when the inner cone head is not installed in the longitudinal arrangement;

[0035] Figure 8 for Figure 7 A side perspective diagram of a double-fuse GIS voltage transformer of the present invention;

[0036] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0037] In the figure: 1- shell, 2- primary side, 3- bottom plate, 4- iron core, 5- wire package, 6- first melting tube, 7- second melting tube, 8- plug cover, 9- fuse retaining ring, 10- melting tube, 11- electrode mesh, 12- electrode, 13- inner cone head, 14- secondary winding outlet terminal. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0039] See also Figures 1-8 As shown, the present invention is a double-fuse GIS voltage transformer, installed within a gas-insulated switchgear (GIS) and comprising a housing 1. In this embodiment, the housing 1 is a fully sealed, seamlessly welded structure made of stainless steel or aluminum alloy. The surface of the housing 1 is treated with a waterproof and salt-fog-resistant coating and is equipped with heat sinks. Inside, the housing 1 is equipped with shock-absorbing pads and a shock-absorbing structure. A base plate 3 is connected to the bottom of the housing 1, providing both ground and suspended mounting options for the voltage transformer. This system is suitable for 35kV double-fuse GIS voltage transformers.

[0040] The housing 1 is well sealed, achieving full enclosure. The gas-insulated switchgear utilizes SF6 gas (sulfur hexafluoride) or other environmentally friendly gases as the insulating medium. The high-voltage components within the gas-insulated switchgear are completely immersed in the high-voltage SF6 gas environment. SF6 gas has excellent insulation and arc-extinguishing capabilities, providing reliable insulation protection in high-voltage environments. The housing 1 also includes a gas flow channel and solid insulation within the channel. The internal structure of the housing 1 features multi-layer insulation, combining gas and solid insulation to enhance insulation performance. The internal gas flow channel ensures uniform distribution of the insulating gas, preventing partial discharge.

[0041] In some embodiments, the solid insulating part is a ceramic insulator or a silicone rubber insulating part arranged in the shell 1, which has excellent electrical insulation performance and mechanical strength. Among them, the solid insulating part is set to a spiral type, which can improve the creepage distance and pollution flashover resistance performance, and is suitable for various harsh environments. A multi-layer insulation structure design is adopted inside to further improve the insulation strength and safety.

[0042] A gas pressure monitoring device is also provided in the housing 1 for monitoring the pressure of the insulating gas in real time to ensure that it is within a normal range.

[0043] In this embodiment, the double-fuse GIS voltage transformer of the utility model adopts a high insulation and fully enclosed design, which improves the reliability of the equipment, extends its service life, and reduces maintenance costs. This double-fuse GIS voltage transformer has excellent sealing properties, achieving complete sealing of the internal part of the equipment, preventing the external environment from affecting the equipment and reducing the failure rate. SF6 gas has excellent insulation and arc extinguishing capabilities, enabling long-term stable operation in high-voltage environments, ensuring the reliability of the equipment. The use of SF6 gas (sulfur hexafluoride) or other environmentally friendly gases as the insulating medium in gas-insulated switchgear effectively reduces the aging rate of internal components and extends the service life of the equipment. The fully enclosed design and high-quality insulating materials make the equipment less susceptible to external environmental influences, reducing the frequency and cost of maintenance.

[0044] The housing 1 is provided with a primary side 2 and a secondary side, which are used for sensing the voltages on the primary side 2 and the secondary side respectively. The double-fuse GIS voltage transformer also includes a voltage sensing unit, which is used to convert the high voltage on the primary side 2 into a low voltage on the secondary side in proportion through the principle of electromagnetic induction, for use by measuring instruments and relay protection devices. The housing 1 is also provided with a double-fuse protection structure, which is an independent fuse protection structure arranged in the housing 1, including a first fuse 6 and a second fuse 7 arranged at the primary side end, which are used to deal with overcurrent or short circuit faults from the primary side 2, one of the fuses quickly melts to cut off the fault current; the secondary side is also provided with a fuse device such as a fuse, a fuse, or a fuse, which is located at the lead portion of the secondary winding output terminal 14 or the lead terminal connection, and can be reasonably selected and set according to user needs.

[0045] In this embodiment, both the primary side 2 and the secondary side are made of copper wires arranged in layers along the axial direction and wound on the iron core 4. The copper wires wound on the iron core 4 are formed into a wire package 5 wound on the iron core 4 through pre-winding, intermediate layers and final winding. The wire package 5 is a fully insulated wire package. The fully insulated wire package is wound with a primary wire on both sides. The wire package winding is designed in a slot shape, and the middle groove is the insulation distance reserved for resin casting.

[0046] In this embodiment, the primary side 2 and the secondary side are internally integrated with current sensors and temperature sensors, which are used to monitor the current changes and operating temperature of the secondary side respectively to avoid overheating damage; cooling ducts are also provided inside the primary side 2 and the secondary side.

[0047] The first and second fuse tubes 6 and 7 of the dual-fuse protection structure each include a plug cap 8 disposed at one end of the voltage transformer housing, a fuse retaining ring 9 disposed within the voltage transformer to abut the plug cap 8 and the fuse tube 10. The fuse tube 10 is provided with an electrode mesh 11, which is connected to an electrode 12, which is connected to an inner cone 13 disposed at the other end of the voltage transformer housing. The electrode mesh 11 of the first and second fuse tubes 6 and 7 is connected to the coil 5 of the primary side 2, and the secondary winding outlet 14 is led out from the bottom of the voltage transformer housing. The coil 5 is connected to the electrode mesh 11 at the left end of the dual-fuse GIS voltage transformer at one end, and to the electrode mesh 11 at the right end at the other end of the dual-fuse GIS voltage transformer at the other end.

[0048] In this embodiment, the double-fuse GIS voltage transformer of the utility model employs a dual protection mechanism, enhancing system safety. The inner cone head 13 can be positioned horizontally or vertically, and an EN 50181 TYPE C inner cone head can also be installed within the inner cone head 13. By equipping the primary side 2 of the voltage transformer with double fuses, dual overcurrent and short-circuit protection is provided. Even in the event of a fault, the operation of the fuse at one end continues to protect the system, preventing further damage. The fuse can respond to overcurrent and short-circuit conditions in milliseconds, quickly shutting off the fault current and preventing impact on equipment and the power grid.

[0049] In summary, the double-fuse GIS voltage transformer of the utility model significantly improves the safety, reliability and maintainability of the equipment through its dual protection mechanism, high insulation performance and the use of environmentally friendly gases, extends its service life and reduces operating costs, providing a more advanced and comprehensive solution for the power system. It is widely used in urban power grids, industrial power supply, rail transportation and other fields.

[0050] Unlike traditional voltage transformers that only have a fuse at one end, the double-fuse GIS voltage transformer of the present invention is equipped with a double-fuse protection structure on the primary side of the GIS fully insulated voltage transformer. This double-fuse design not only requires the rational arrangement of two sets of fuse devices within a limited space, but also ensures that they can independently and collaboratively perform overvoltage protection without interfering with the normal operation of the transformer. This involves a unique internal structural layout and insulation isolation technology. During the manufacturing process, the double-fuse GIS voltage transformer of the present invention adopts a mold cavity double-fuse shielding pre-installation process. The installation of the shielding net can ensure a uniform electric field distribution without causing discharge due to excessive local electric fields and leading to product breakdown. At the same time, the electrode net can block or absorb surrounding electromagnetic interference, reducing the impact of external electromagnetic fields on sensitive components within the voltage transformer.

[0051] This new double-fuse GIS voltage transformer provides dual overcurrent and short-circuit protection by equipping the primary side of the voltage transformer with a double fuse. Compared to traditional solutions that only use fuses on one end, this design significantly enhances system safety and reliability, improving stability and availability by providing immediate disconnection in the event of a single transformer failure.

[0052] Furthermore, power outage duration can be reduced. Rapid fault isolation and recovery are crucial in power systems. The design features and protection mechanisms of this utility model indirectly help mitigate the impact of resonance on the system. The dual-fuse design allows for faster fault location and isolation, minimizing the impact on the entire power grid, shortening troubleshooting time, and improving the continuity and stability of power supply.

[0053] Moreover, GIS technology itself is known for its high insulation performance and sealing. Combined with the double-fuse tube design, the voltage transformer operates more safely and stably in high-voltage environments, reducing the impact of external environmental factors (such as humidity and dust) on the equipment and extending its service life.

[0054] Therefore, the double-fuse GIS voltage transformer of the present invention provides a more advanced and comprehensive solution for the power system through its advantages in protection, reliability, easy maintenance, monitoring and adaptability to high-voltage environments.

[0055] In some embodiments, the double-fuse GIS voltage transformer can also be connected to an intelligent monitoring system, which includes sensor devices integrated in the voltage transformer for real-time monitoring of the equipment operating status and transmitting it to a remote monitoring center for real-time monitoring and fault warning.

[0056] In this embodiment, the sensor devices in the intelligent monitoring system include a voltage sensor, a current sensor, a temperature sensor and a gas pressure sensor. The voltage sensor is in a fast response mode and is used to monitor the voltage status in real time. The current sensor is a Hall effect sensor with a wide-range and fully enclosed design to adapt to different current load requirements. The sensor surface of the temperature sensor is coated with a protective coating to ensure the accuracy of temperature measurement and prevent corrosion and environmental influences. The gas pressure sensor is provided with a high-temperature resistant structure to adapt to the accuracy of pressure measurement in a high-temperature environment.

[0057] In this embodiment, the convenient modular design of the double-fuse GIS voltage transformer of the utility model enables intelligent monitoring and remote management. The modular design of this double-fuse GIS voltage transformer makes on-site installation and replacement of the voltage transformer more convenient, requiring only the replacement of damaged modules, reducing downtime and improving work efficiency. Integrated sensors and communication interfaces enable real-time monitoring of key parameters such as voltage and temperature, ensuring optimal equipment operation. When an anomaly is detected, the intelligent monitoring system promptly sends an alarm signal to the control center via the network, enabling operations and maintenance personnel to quickly respond and handle the issue, improving system reliability and safety.

[0058] Under normal operating conditions, the high-voltage current in the GIS system flows through the fuse 10 into the primary winding of the voltage transformer, generating a magnetic field that in turn induces a low-voltage signal in the secondary winding. These signals are transmitted to measurement and protection equipment for monitoring and protection of the power system. If a system anomaly occurs, such as an overvoltage, the fuse 10 quickly responds, shutting off the abnormal current and protecting the equipment from damage, thus achieving overvoltage protection. The intelligent monitoring system continuously monitors equipment status. Upon detecting any anomaly (such as a pressure drop or excessive temperature), it immediately sends an alarm signal to the control center via the network, prompting operations and maintenance personnel to take appropriate action, thus achieving status monitoring and alarming.

[0059] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. The preferred embodiments do not describe all details in detail, nor do they limit the present invention to the specific embodiments described. Obviously, many modifications and variations are possible based on the contents of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A double-fuse GIS voltage transformer, which is arranged in a gas-insulated switchgear, characterized in that: include: housing (1); The primary side (2) and the secondary side are used for sensing the primary side and secondary side voltages respectively; The double-melting tube protection structure is an independent melting tube protection structure arranged in a housing (1), comprising a first melting tube (6) and a second melting tube (7) arranged at the end of the primary side (2).

2. The double-fuse GIS voltage transformer according to claim 1, characterized in that: The housing (1) is a fully sealed shell structure made of stainless steel or aluminum alloy by seamless welding.

3. The double-fuse GIS voltage transformer according to claim 2, characterized in that: The housing (1) is provided with a heat sink, the interior of the housing (1) is provided with a shock-absorbing pad and a shock-absorbing structure, and the bottom of the housing (1) is connected to a base plate (3) for ground installation and suspension installation.

4. The double-fuse GIS voltage transformer according to claim 3, characterized in that: A gas circulation channel and a solid insulating member located in the gas circulation channel are also provided in the housing (1).

5. The double-fuse GIS voltage transformer according to claim 4, characterized in that: The solid insulating part is a ceramic insulator or a silicone rubber insulating part arranged in the housing (1), and the solid insulating part is arranged in a spiral shape.

6. The double-fuse GIS voltage transformer according to any one of claims 1 to 5, characterized in that: The primary side (2) and the secondary side are both arranged in layers along the axial direction using copper wires wound on the iron core (4). The copper wires wound on the iron core (4) are formed into a wire package (5) wound on the iron core (4) through pre-winding, intermediate layers and final winding. The wire package (5) is a fully insulated wire package. The fully insulated wire package is wound with primary wires on both sides. The wire package winding is designed in a slot shape, and the middle groove is an insulation distance reserved for resin casting.

7. The double-fuse GIS voltage transformer according to claim 6, characterized in that: Current sensors and temperature sensors are integrated inside the primary side (2) and the secondary side. Cooling ducts are also provided inside the primary side (2) and the secondary side, and an air duct is provided inside the winding structure.

8. The double-fuse GIS voltage transformer according to claim 7, characterized in that: The first melting tube (6) and the second melting tube (7) of the double melting tube protection structure both include a plug cover (8) arranged at one end of a voltage transformer housing, a fuse retaining ring (9) arranged inside the voltage transformer and abutting against the plug cover (8) and the melting tube (10), an electrode mesh (11) is provided on the melting tube (10), the electrode mesh (11) is connected to an electrode (12), and the electrode (12) is connected to an inner cone head (13) arranged at the other end of the voltage transformer housing.

9. The double-fuse GIS voltage transformer according to claim 8, characterized in that: The electrode networks (11) of the first melting tube (6) and the second melting tube (7) are connected to the coil (5) of the primary side (2), and the secondary side winding outlet terminal (14) is led out from the bottom of the housing of the voltage transformer.

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