A compartmentalized three-phase voltage transformer

Abstract

The utility model relates to a kind of three-phase voltage transformers of compartment, including shell and first, second single-phase mutual inductor, the top of shell is arranged three-phase, each phase includes a root of fusing tube, shell also includes three internal fusing tubes, the inner wall of the tube bottom of each internal fusing tube is arranged with spring contact finger, fuse is placed in tube, second nut is installed in tube mouth, the primary winding of first, second single-phase mutual inductor is electrically connected with first to fourth electrically conductive pole respectively, define three fusing tubes as first to third fusing tube, the other end of first electrically conductive pole is electrically connected with the spring contact finger of first fusing tube, the other end of second electrically conductive pole, third electrically conductive pole is electrically connected with the spring contact finger of second fusing tube, the other end of fourth electrically conductive pole is electrically connected with the spring contact finger of third fusing tube. Utilize a kind of three-phase voltage transformers of compartment designed by the utility model, can solve the problem of traditional three-phase voltage transformer common fusing tube, compact structure, increased operation and maintenance difficulty, reduced replacement efficiency.

Description

Technical Field

[0001] This utility model relates to the field of power equipment technology, specifically to a compartmentalized three-phase voltage transformer. Background Technology

[0002] Voltage transformers, as key components for voltage sampling and monitoring in high-voltage power systems, are widely used in ring main units and medium- and high-voltage distribution systems. Traditional three-phase voltage transformers typically employ a three-compartment structure, where each phase has a shared fuse tube containing a fuse core and an elbow-shaped connector. While compact, this structure has a significant drawback: if the fuse core blows, the fuse tube must be removed to replace it. Since this fuse tube shares a compartment with the elbow-shaped connector, replacing the fuse core inevitably requires first removing the elbow-shaped connector. Due to the high contact pressure, compact space, and high installation strength required during elbow-shaped connector installation, this operation not only increases maintenance difficulty but also significantly reduces replacement efficiency.

[0003] Therefore, existing technologies have shortcomings and need to be improved and developed. Utility Model Content

[0004] This utility model provides a compartmentalized three-phase voltage transformer to address the problem that traditional three-phase voltage transformers typically employ a three-compartment structure, where each phase has a shared fuse tube with a fuse core and an elbow plug. While this structure is compact, it has significant drawbacks: if the fuse core melts, the fuse tube must be disassembled to replace it. Since the fuse tube is connected to the elbow plug in a shared compartment, replacing the fuse core inevitably requires disassembling the elbow plug first. Due to the high contact pressure, compact space, and high installation strength of the elbow plug, this operation not only increases the difficulty of operation and maintenance but also significantly reduces replacement efficiency.

[0005] This utility model provides a compartmentalized three-phase voltage transformer, including a housing. A first single-phase transformer and a second single-phase transformer are fixed inside the housing. Three phases (A, B, and C) are arranged on the top of the housing, each phase including a fuse tube. A screw threaded to the inner wall of the bottom of each phase's fuse tube is connected to a first nut located on the outer wall of the bottom of the tube. The housing also includes three internal fuse tubes. Each internal fuse tube has a spring contact finger arranged on the inner wall of its bottom, a fuse placed inside, and a second nut installed at its opening. When the fuse is placed in the internal fuse tube, an end cap threaded to the second nut is used to press the fuse and the spring contact finger together under the pressure of the end cap. The three fuse tubes are defined as a first fuse tube, a second fuse tube, and a third fuse tube. The first fuse tube's... Two nuts are electrically connected to the first nut of the fuse tube in phase A, the second nut of the second fuse tube is electrically connected to the first nut of the fuse tube in phase B, and the second nut of the third fuse tube is electrically connected to the first nut of the fuse tube in phase C. The primary winding of the first single-phase transformer is electrically connected to a first conductive rod and a second conductive rod, and the primary winding of the second single-phase transformer is electrically connected to a third conductive rod and a fourth conductive rod. The other end of the first conductive rod is electrically connected to the spring contact finger of the first fuse tube, the other end of the second conductive rod and the third conductive rod are electrically connected to the spring contact finger of the second fuse tube, and the other end of the fourth conductive rod is electrically connected to the spring contact finger of the third fuse tube. The secondary windings of the first single-phase transformer and the second single-phase transformer are grounded.

[0006] Furthermore, the second fuse tube is located between the first single mutual inductor and the second single mutual inductor, the first fuse tube is located on one side of the first single mutual inductor and on a different side from the second fuse tube, and the third fuse tube is located on one side of the second single mutual inductor and on a different side from the second fuse tube.

[0007] Furthermore, at least two non-contacting hexagonal nuts are arranged at the bottom of the housing. The secondary winding of the first single mutual inductor is connected to one of the hexagonal nuts via a wire, and the secondary winding of the second single mutual inductor is connected to the other hexagonal nut via a wire.

[0008] Furthermore, a third shielding mesh is provided on the outer casing of the fuse tubes outside phases A, B, and C. The third shielding mesh is not in contact with the fuse tubes outside phases A, B, and C. The third shielding mesh on the outer casing of phase A is electrically connected to the first insert and the second insert. The third shielding mesh on the outer casing of phase B is electrically connected to the second insert and the third insert. The third shielding mesh on the outer casing of phase C is electrically connected to the third insert and the fourth insert. At least three non-contact hexagonal nuts are arranged at the bottom of the housing. One of the hexagonal nuts that is not connected to the secondary winding of the first single mutual inductor and the secondary winding that is not connected to the second single mutual inductor is connected to the second insert.

[0009] Furthermore, the inner molten tube is fitted with a first shielding mesh and a second shielding mesh that do not contact each other. The first shielding mesh is fitted at the bottom of the inner molten tube wall, and the second shielding mesh is fitted at the top of the inner molten tube wall. The end of the second shielding mesh away from the spring contact finger is fixed to the second nut.

[0010] Furthermore, the first shielding mesh, the second shielding mesh, and the third shielding mesh are stainless steel shielding meshes.

[0011] Furthermore, when phases A, B, and C are electrically connected to the elbow plug, the distance between the screw and the opening of the fusible tube where the screw is located is defined as H, and the length of the contact head of the elbow plug is defined as L, where H and L are positive numbers, and H≤L.

[0012] Furthermore, the interior of the housing is filled with epoxy resin.

[0013] Furthermore, a nameplate and a polarity indicator are adhered to the exterior of the housing.

[0014] Furthermore, the end cap is a brass end cap.

[0015] Beneficial effects:

[0016] As can be seen from the above technical solution, this utility model provides a compartmentalized three-phase voltage transformer. By constructing a compartmentalized three-phase voltage transformer with six fuse sleeves, it provides a voltage transformer design with a clear structure, compartmentalized arrangement, and well-defined connection logic. This makes the current path clear and controllable, fault diagnosis accurate, and facilitates debugging and fault analysis. Simultaneously, the compartmentalized structure achieves the goal of non-interference between fuse replacement and elbow plug operation, significantly improving overall operation and maintenance efficiency and enhancing the comprehensive performance of the transformer in terms of fault maintenance, installation adaptation, electric field shielding, and partial discharge performance. Specifically, this is reflected as follows:

[0017] 1. Improved ease of fuse replacement: The fuse is independently arranged in the lower fuse tube, and the user only needs to remove the end cover to complete the fuse replacement. There is no need to operate the elbow plug already installed on the upper layer, avoiding heavy reassembly and significantly reducing maintenance labor intensity.

[0018] 2. Enhanced adaptability of transformer structure: The position of the upper three-phase fuse tubes is not fixed. Since fuses do not need to be installed, the phase spacing can be adjusted according to user needs, breaking through the limitations of traditional coil windings on fuse tube arrangement, and adapting to different models and specifications of ring main units or prefabricated substations.

[0019] 3. Optimized electric field distribution and partial discharge performance: The use of shielding mesh and grounding device to rationally guide the high voltage field path effectively suppresses partial discharge and improves the long-term stability and insulation reliability of the product under high voltage environment.

[0020] 4. Achieve standardization and mass production: Modular structures such as end caps, fusion tubes, and shielding meshes are easy to design and produce in a standardized manner, which is conducive to stable manufacturing processes and controllable maintenance costs.

[0021] It should be understood that all combinations of the foregoing concepts and the additional concepts described in more detail below can be considered part of the inventive subject matter of this disclosure, provided that such concepts do not contradict each other.

[0022] The foregoing and other aspects, embodiments, and features of the teachings of the present invention will be more fully understood from the following description in conjunction with the accompanying drawings. Other additional aspects of the invention, such as features and / or beneficial effects of exemplary embodiments, will become apparent from the following description or may be learned through practice of specific embodiments according to the teachings of the present invention. Attached Figure Description

[0023] The accompanying drawings are not drawn to scale. In the drawings, each identical or nearly identical component shown in the various figures may be denoted by the same reference numeral. For clarity, not every component is labeled in each figure. Embodiments of various aspects of the invention will now be described by way of example and with reference to the accompanying drawings, wherein:

[0024] Figure 1 This is a first-angle structural cross-sectional view of a compartmentalized three-phase voltage transformer according to an embodiment of this application.

[0025] Figure 2 This is a second-angle structural cross-sectional view of a compartmentalized three-phase voltage transformer according to an embodiment of this application.

[0026] Figure 3 This is a front view of a compartmentalized three-phase voltage transformer according to an embodiment of this application.

[0027] Explanation of icon numbers:

[0028] 1. Housing; 2. First single mutual inductor; 3. Second single mutual inductor; 4. Screw; 5. First nut; 6. Spring contact finger; 7. Fuse; 8. Second nut; 9. First conductive rod; 10. Second conductive rod; 11. Third conductive rod; 12. Fourth conductive rod; 13. First shielding mesh; 14. Second shielding mesh; 15. Third shielding mesh; 16. First insert; 17. Second insert; 18. Third insert; 19. Fourth insert. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art to which this invention pertains.

[0030] The terms "first," "second," and similar words used in the specification and claims of this patent application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, unless the context clearly indicates otherwise, the singular forms of "an," "a," or "the," etc., do not indicate a quantity limitation, but rather indicate the presence of at least one. Terms such as "comprising" or "including" mean that the element or object preceding "comprising" encompasses the features, integrals, steps, operations, elements, and / or components listed following "comprising" or "including," and do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or collections thereof. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; these relative positional relationships may change accordingly when the absolute position of the described object changes.

[0031] Traditional three-phase voltage transformers in the current technology typically adopt a three-compartment structure, where each phase has a shared fuse tube containing a fuse core and an elbow plug. While the structure is compact, it has a significant drawback: if the fuse core blows, the fuse tube must be removed to replace it. Since this fuse tube shares a compartment with the elbow plug, replacing the fuse core inevitably requires first removing the elbow plug. Due to the high contact pressure, compact space, and high installation strength required during the elbow plug installation process, this operation not only increases the difficulty of operation and maintenance but also significantly reduces replacement efficiency.

[0032] In view of this, the present invention provides a compartmentalized three-phase voltage transformer, referring to... Figures 1-3 It includes a housing 1, and a first single mutual sensor 2 and a second single mutual sensor 3 are fixed inside the housing 1.

[0033] The top of the shell 1 is arranged with three phases A, B and C, each phase including a molten tube, and the screw 4 on the inner wall of the bottom of the molten tube of each phase is threaded to the first nut 5 located on the outer wall of the bottom of the tube;

[0034] The housing 1 also includes three internal fuse tubes. Each internal fuse tube has a spring contact finger 6 arranged on the inner wall of its bottom, a fuse 7 placed inside the tube, and a second nut 8 installed at the tube opening. When the fuse 7 is placed in the internal fuse tube, an end cap is threaded onto the second nut 8 to press the fuse 7 and the spring contact finger 6 together under the pressure of the end cap. The second nut 8 of the first fuse tube is electrically connected to the first nut 5 of the fuse tube of phase A, the second nut 8 of the second fuse tube is electrically connected to the first nut 5 of the fuse tube of phase B, and the second nut 8 of the third fuse tube is electrically connected to the first nut 5 of the fuse tube of phase C.

[0035] The primary winding of the first single mutual inductor 2 is electrically connected to a first conductive rod 9 and a second conductive rod 10. The primary winding of the second single mutual inductor 3 is electrically connected to a third conductive rod 11 and a fourth conductive rod 12. The three fuse tubes are defined as the first fuse tube, the second fuse tube, and the third fuse tube. The other end of the first conductive rod 9 is electrically connected to the spring contact finger 6 of the first fuse tube. The other ends of the second conductive rod 10 and the third conductive rod 11 are electrically connected to the spring contact finger 6 of the second fuse tube. The other end of the fourth conductive rod 12 is electrically connected to the spring contact finger 6 of the third fuse tube.

[0036] The secondary windings of the first single mutual inductor 2 and the second single mutual inductor 3 are grounded.

[0037] This application provides an embodiment that establishes independent connection paths between the primary winding and each phase fuse core, making the current path clear and controllable, fault diagnosis accurate, and facilitating debugging and fault analysis. Simultaneously, the compartmentalized structure achieves the goal of non-interference between fuse core replacement and elbow plug operation, improving overall maintenance efficiency. The fuse tubes of phases A, B, and C are used to introduce power, with the first nut 5 connected to the corresponding second nut 8 via electrical wires; the lower fuse tube is equipped with a spring contact finger 6 and a fuse 7, forming a protection path; the primary winding is electrically connected to the spring contact finger 6 via a conductive rod, forming a closed primary side circuit; the secondary winding is grounded to form a complete detection system; the overall structure realizes the basic workflow of high-voltage input, fuse protection, mutual inductance, and secondary output. The structural design rationally isolates the high-voltage input from the mutual inductor detection circuit; the layered and compartmentalized structure significantly improves the efficiency and safety of fuse core replacement during faults; the electrical connection logic is clear and reliable, facilitating operation and maintenance.

[0038] When the current transformer is connected to the system through the elbow plug, the current flows from the contact head of the elbow plug through the screw 4, the first nut 5, the second nut 8, the fuse 7, and the spring contact finger 6, and then flows into the current transformer through the first conductive rod 9, so the current transformer can operate normally. When the current transformer malfunctions, the fuse 7 blows and cuts off the power. At this time, the fuse 7 can be removed from the internal fuse tube and replaced directly without disassembling the elbow plug.

[0039] Due to internal coil arrangement issues, the phase spacing of the A, B, and C phase fuse tubes in conventional three-phase mutual inductors is limited, making it impossible to meet customers' requirements for very small phase spacing. However, this product separates the fuse core and elbow plug, and the A, B, and C phase fuse tubes are not limited by coil arrangement. The phase spacing can be adjusted at will according to actual usage needs, meeting the diverse needs of the market.

[0040] In some embodiments, the second fuse tube is located between the first single-phase transformer 2 and the second single-phase transformer 3, the first fuse tube is located on one side of the first single-phase transformer 2 and on a different side from the second fuse tube, and the third fuse tube is located on one side of the second single-phase transformer 3 and on a different side from the second fuse tube. (Refer to...) Figure 2 With the center of the housing 1 as the reference, the first fuse tube is located to the left of the first single mutual sensor 2, the second fuse tube is located between the first single mutual sensor 2 and the second single mutual sensor 3, and the third fuse tube is located to the right of the second single mutual sensor 3.

[0041] By placing the second fuse tube between two single-phase inductors and setting the first and third fuse tubes on the left and right sides, the structure is symmetrical, the wiring is shorter and more compact, which helps to reduce inductive interference and improve product consistency and electrical performance.

[0042] In some embodiments, at least two non-contacting hexagonal nuts are arranged at the bottom of the housing 1. The secondary winding of the first single mutual inductor 2 is connected to one of the hexagonal nuts by a wire, and the secondary winding of the second single mutual inductor 3 is connected to the other hexagonal nut by a wire.

[0043] By arranging non-contact hexagonal nuts at the bottom of housing 1, a reliable distributed connection between the secondary winding of the current transformer and the grounding conductor is achieved, making the grounding wiring more flexible, the electrical interface more standardized, and improving the wiring safety of the current transformer and the efficiency of engineering installation.

[0044] In some embodiments, reference is made to Figure 2The outer casing of the fuse tubes of phases A, B, and C is provided with a third shielding mesh 15. The third shielding mesh 15 does not contact the fuse tubes of phases A, B, and C. The third shielding mesh 15 of phase A is electrically connected to the first insert 16 and the second insert 17. The third shielding mesh 15 of phase B is electrically connected to the second insert 17 and the third insert 18. The third shielding mesh 15 of phase C is electrically connected to the third insert 18 and the fourth insert 19. At least three non-contact hexagonal nuts are arranged at the bottom of the housing 1. One of the hexagonal nuts that is not connected to the secondary winding of the first single mutual inductor 2 and not connected to the secondary winding of the second single mutual inductor 3 is connected to the second insert 17.

[0045] By installing a third shielding mesh 15 outside the upper fused tube and electrically isolating it from the lower first shielding mesh 13, the influence of external interference electric fields on the transformer body is further suppressed, improving the product's anti-electromagnetic interference capability and ensuring the stability of measurement signals and data accuracy. A hexagonal nut is connected to the second insert 17. After installing the elbow plug, the high-voltage side of the three-phase voltage transformer is grounded. Testing is conducted according to national standards for partial discharge testing, increasing the partial discharge pass rate of the three-phase voltage transformer with the elbow plug from 0% to 98%. When the number of hexagonal nuts is greater than three, the hexagonal nuts not used for grounding can be detachably connected to the base plate at the bottom of the housing 1, facilitating the placement of the three-phase voltage transformer on a flat surface.

[0046] In some embodiments, the inner molten tube is fitted with a first shielding mesh 13 and a second shielding mesh 14 that do not contact each other. The first shielding mesh 13 is fitted at the bottom of the inner molten tube wall, and the second shielding mesh 14 is fitted at the top of the inner molten tube wall. The end of the second shielding mesh 14 away from the spring contact finger 6 is fixed to the second nut 8.

[0047] The first shielding mesh 13 is located at the bottom of the pipe, and the second shielding mesh 14 is located at the top of the pipe, forming an electric field distribution adjustment structure. This structure can effectively weaken the concentration of the electric field gradient around the fuse 7, thereby reducing the electric field stress points, reducing partial discharge, and uniformizing the electric field around the fuse 7, effectively extending the life of the product's insulation system.

[0048] In some embodiments, the first shielding mesh 13, the second shielding mesh 14, and the third shielding mesh 15 are stainless steel shielding meshes.

[0049] In some embodiments, when phases A, B, and C are electrically connected to the elbow plug, the distance between the screw 4 and the opening of the fusible tube is defined as H, and the length of the contact head of the elbow plug is defined as L, where H and L are positive numbers, and H ≤ L.

[0050] By limiting the length L of the elbow plug contact head to be no less than the distance H from the screw 4 to the fusible tube opening, reliable plug contact is ensured, guaranteeing effective contact between the elbow plug and the screw 4 after insertion. This avoids problems such as incomplete connection and arc discharge, improves the reliability of electrical connection and operational safety, and prevents heat loss or breakdown during high-voltage operation.

[0051] In some embodiments, the interior of the housing 1 is filled with epoxy resin. After the internal structure is assembled, the entire interior of the housing 1 is sealed by pouring epoxy resin, forming an integral insulating medium. This improves the mechanical strength, moisture resistance, and environmental resistance of the transformer, effectively preventing insulation breakdown phenomena such as corona discharge and creepage in air, and extending the service life of the equipment.

[0052] In some embodiments, a nameplate and a polarity marking plate are adhered to the exterior of the housing 1.

[0053] In some embodiments, the end cap is a brass end cap.

[0054] In summary, this utility model provides a compartmentalized three-phase voltage transformer. By constructing a compartmentalized three-phase voltage transformer with six fuse sleeves, it offers a voltage transformer design with a clear structure, compartmentalized arrangement, and well-defined connection logic. This makes the current path clear and controllable, fault diagnosis accurate, and facilitates debugging and fault analysis. Simultaneously, the compartmentalized structure achieves the goal of eliminating interference between fuse 7 replacement and the elbow plug, significantly improving overall operation and maintenance efficiency and enhancing the transformer's comprehensive performance in fault maintenance, installation adaptation, electric field shielding, and partial discharge performance. Specifically, it improves the convenience of fuse 7 replacement: by independently arranging fuse 7 in the lower fuse tube, users only need to remove the end cover to complete fuse 7 replacement, without needing to operate the upper-level installed elbow plug, avoiding intensive reassembly and significantly reducing maintenance labor intensity. Enhanced transformer structural adaptability: The position of the upper three-phase fuse tubes is not fixed. Since fuse 7 does not need to be installed, the phase spacing can be adjusted according to user needs, breaking through the limitations of traditional coil windings on fuse tube arrangement, and adapting to different models and specifications of ring main units or prefabricated substations. Optimized electric field distribution and partial discharge performance: The use of shielding mesh and grounding devices rationally guides the high-voltage field strength path, effectively suppressing partial discharge and improving the long-term stability and insulation reliability of the product under high-voltage environments. Achieved standardization and mass production: The modular structure of end caps, fuse tubes, shielding mesh, etc., facilitates standardized design and production, which is conducive to stable manufacturing processes and controllable maintenance costs.

[0055] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A compartmentalized three-phase voltage transformer, comprising a housing, wherein a first single-phase transformer and a second single-phase transformer are fixed within the housing, characterized in that, The top of the shell is arranged with three phases A, B and C, each phase including a molten tube, and the screw threaded on the inner wall of the bottom of the molten tube of each phase is connected to the first nut located on the outer wall of the bottom of the tube. The housing also includes three internal fuse tubes. Each internal fuse tube has a spring contact finger arranged on the inner wall of its bottom, a fuse placed inside the tube, and a second nut installed at its opening. When the fuse is placed in the internal fuse tube, an end cap is threaded onto the second nut to press the fuse and the spring contact finger together under the pressure of the end cap. The three fuse tubes are defined as a first fuse tube, a second fuse tube, and a third fuse tube. The second nut of the first fuse tube is electrically connected to the first nut of the fuse tube in phase A, the second nut of the second fuse tube is electrically connected to the first nut of the fuse tube in phase B, and the second nut of the third fuse tube is electrically connected to the first nut of the fuse tube in phase C. The primary winding of the first single mutual inductor is electrically connected to a first conductive rod and a second conductive rod. The primary winding of the second single mutual inductor is electrically connected to a third conductive rod and a fourth conductive rod. The other end of the first conductive rod is electrically connected to the spring contact finger of the first fuse. The other ends of the second conductive rod and the third conductive rod are electrically connected to the spring contact finger of the second fuse. The other end of the fourth conductive rod is electrically connected to the spring contact finger of the third fuse. The secondary windings of the first single mutual inductor and the second single mutual inductor are grounded.

2. A compartmentalized three-phase voltage transformer according to claim 1, characterized in that, The second fuse tube is located between the first single mutual inductor and the second single mutual inductor. The first fuse tube is located on one side of the first single mutual inductor and on a different side from the second fuse tube. The third fuse tube is located on one side of the second single mutual inductor and on a different side from the second fuse tube.

3. A compartmentalized three-phase voltage transformer according to claim 1, characterized in that, At least two non-contacting hexagonal nuts are arranged at the bottom of the housing. The secondary winding of the first single mutual inductor is connected to one of the hexagonal nuts by a wire, and the secondary winding of the second single mutual inductor is connected to the other hexagonal nut by a wire.

4. A compartmentalized three-phase voltage transformer according to claim 3, characterized in that, The outer casing of the fuse tubes outside phases A, B, and C is provided with a third shielding mesh. The third shielding mesh is not in contact with the fuse tubes outside phases A, B, and C. The third shielding mesh outside phase A is electrically connected to the first insert and the second insert. The third shielding mesh outside phase B is electrically connected to the second insert and the third insert. The third shielding mesh outside phase C is electrically connected to the third insert and the fourth insert. At least three non-contact hexagonal nuts are arranged at the bottom of the housing. One of the hexagonal nuts that is not connected to the secondary winding of the first single mutual inductor and the secondary winding that is not connected to the second single mutual inductor is connected to the second insert.

5. A compartmentalized three-phase voltage transformer according to claim 4, characterized in that, The inner molten tube is fitted with a first shielding mesh and a second shielding mesh that do not contact each other. The first shielding mesh is fitted at the bottom of the inner molten tube wall, and the second shielding mesh is fitted at the top of the inner molten tube wall. The end of the second shielding mesh away from the spring contact finger is fixed to the second nut.

6. A compartmentalized three-phase voltage transformer according to claim 1, characterized in that, The first shielding mesh, the second shielding mesh, and the third shielding mesh are stainless steel shielding meshes.

7. A compartmentalized three-phase voltage transformer according to claim 1, characterized in that, When phases A, B, and C are electrically connected to the elbow plug, the distance between the screw and the opening of the fusible tube where the screw is located is defined as H, and the length of the contact head of the elbow plug is defined as L, where H and L are positive numbers, and H≤L.

8. A compartmentalized three-phase voltage transformer according to claim 1, characterized in that, The interior of the shell is filled with epoxy resin.

9. A compartmentalized three-phase voltage transformer according to claim 1, characterized in that, The exterior of the housing is fitted with a nameplate and a polarity indicator.

10. A compartmentalized three-phase voltage transformer according to claim 1, characterized in that, The end cap is a brass end cap.

Images