Multi-winding high-capacity all-insulation voltage transformer

Abstract

The utility model relates to an electrified railway line measurement and control device, in particular to a multi-winding high-capacity all-insulation voltage transformer. Comprising a bottom plate and a main insulator arranged on the bottom plate, a transformer body and two primary supports connected with the transformer body are arranged in the main insulator in a sealed mode, the transformer body comprises an iron core, secondary windings and primary windings, multiple sets of secondary windings are wound on the outer side of the iron core, and the primary windings are wound on the outer sides of the multiple sets of secondary windings; the top of the main insulator is provided with two primary insulation columns, the tops of the two primary insulation columns are respectively embedded with two secondary high-voltage terminals, and the two primary high-voltage terminals are respectively connected with the two primary supports; and a secondary wiring terminal is arranged at the bottom of the main insulator. The utility model is formed by vacuum casting of epoxy resin, and has the characteristics of small volume, beautiful appearance, flexible installation, easy maintenance and complete functions.

Description

Technical Field

[0001] This utility model relates to a measurement and control device for electrified railway lines, specifically a multi-winding, large-capacity, fully insulated voltage transformer. Background Technology

[0002] Voltage transformers are devices used in power systems or electrical control systems to measure voltage and electrical energy. To achieve miniaturization of switchgear and ease of maintenance, conventional voltage transformers suffer from drawbacks such as fewer windings, larger size, fewer functions, cumbersome installation, and the need for maintenance, resulting in switchgear that is also relatively large. To achieve the functional characteristics of miniaturized switchgear, multiple windings, large capacity, and flexible installation, it is necessary to design and develop a small-sized, multi-winding, large-capacity, and fully functional fully insulated voltage transformer. This would reduce the overall size of the switchgear, improve its technical equipment level, reduce its economic cost, and enhance its market competitiveness. Utility Model Content

[0003] To address the aforementioned problems, the purpose of this utility model is to provide a multi-winding, high-capacity, fully insulated voltage transformer to meet the requirements of small size, multiple windings, large capacity, and full functionality of voltage transformers.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] This utility model provides a multi-winding, high-capacity, fully insulated voltage transformer, including a base plate and a main insulator disposed on the base plate. The main insulator encloses a transformer body and two primary supports connected to the transformer body. The transformer body includes an iron core, secondary windings, and primary windings. Multiple sets of secondary windings are wound around the outside of the iron core, and primary windings are wound around the outside of the multiple sets of secondary windings. Two primary insulating posts are provided on the top of the main insulator, and two primary high-voltage terminals are respectively embedded on the top of the two primary insulating posts. The two primary high-voltage terminals are respectively connected to the two primary supports. Secondary wiring terminals are provided at the lower front part of the main insulator.

[0006] The primary support includes a metal conductive sheet and a metal rod connected to the top of the metal conductive sheet. The metal conductive sheet has an arc-shaped structure and is tightly fitted with the outer diameter of the primary winding coil. The upper end of the metal rod is connected to the primary high-voltage terminal.

[0007] The metal rod has an L-shaped structure, and its upper part is housed within the primary insulating column.

[0008] The outer surface of the primary insulating column is provided with multiple arc-shaped skirts of varying sizes.

[0009] The outer side of the secondary winding portion of the iron core is wrapped with an iron core insulation layer. Multiple sets of the secondary windings are wound on the outer side of the iron core insulation layer, and PMP composite paper insulation is added between the layers of the secondary windings. A layer of semi-conductive crepe paper is half-lapped on the outer side of the secondary windings. The primary winding is wound on an insulating frame. A silicone strip is wrapped around each of the two circular ends of the insulating frame and fixed with double-sided tape. A whole sheet of semi-conductive crepe paper is wrapped inside the insulating frame. Semi-conductive crepe paper, shaped copper foil, and multiple layers of DMD composite paper are arranged on the outer side of the insulating frame. The outer side of the primary winding is wrapped with shaped copper foil. The metal conductive sheet of the primary support is in close contact with the shaped copper foil. A layer of semi-conductive crepe paper is wrapped around the outer side of the metal conductive sheet. The exposed part of the metal conductive sheet and the metal rod folded into an L-shape is sealed with semi-conductive rubber tape and superimposed with the semi-conductive crepe paper to form a high-voltage shielding layer.

[0010] The core insulation layer is formed by a layer of insulating paperboard and multiple layers of PMP composite paper.

[0011] The portion of the iron core excluding the secondary winding consists of, from the inside out, a self-adhesive tape insulation layer, a molded polyurethane board buffer layer, another self-adhesive tape insulation layer, an outer molded copper foil or aluminum foil, and a semi-conductive crepe paper layer to form a low-voltage shielding layer. A layer of semi-conductive paint is then applied to both axial sides of the wrapped iron core.

[0012] The main insulator is an integral structure cast with epoxy resin. The upper middle part of the main insulator is a horizontal cylindrical shape. The left and right sides of the horizontal cylindrical shape taper downward to the bottom of the main insulator, forming a stepped vertical plane. There is an arc transition between the horizontal cylindrical shape and the stepped vertical plane. The front and rear ends of the main insulator are symmetrical vertical column structures. The vertical column structure includes a semi-cylinder at the bottom and a semi-frustum at the top. There is an arc transition between the semi-frustum and the semi-cylinder. Square protrusions are provided on the left and right sides of the lower part of the semi-cylinder.

[0013] The main insulator has two protrusions on its lower left and right sides, and each protrusion has a base plate mounting insert.

[0014] The lower front end of the main insulator is provided with a secondary wiring platform, the secondary wiring terminals are disposed on the secondary wiring platform, and a wiring protective cover is provided above the secondary wiring platform; a grounding terminal is provided on the base plate.

[0015] This utility model has the following advantages and beneficial effects:

[0016] 1. Small size and full functionality: This utility model has a compact structure, small size and full functionality, and optimized structural design, making it particularly suitable for use with new voltage transformers in power systems;

[0017] 2. Multi-winding, large capacity, and overvoltage protection: This utility model adopts a ring-shaped rolled iron core with large capacity and multiple sets of secondary windings, which have multiple measurement protection functions; the semi-circular metal conductive sheet of the primary bracket is tightly and stably set with the copper foil formed on the outer diameter of the primary winding, which has a high overvoltage resistance capability and can be used in the overvoltage protection line of the power system. It will not have insulation breakdown damage problem when operating under long-term overvoltage conditions.

[0018] 3. Crack resistance and high mechanical strength; This utility model design uses high-performance epoxy resin material to ensure that the product has sufficient mechanical strength and will not deteriorate. It is suitable for various environmental conditions of the State Grid power system and ensures that the product will not experience insulation failures such as resin cracking.

[0019] 4. Easy installation and maintenance-free product: When installing and using this utility model, simply fix the base plate of the current transformer in the switch cabinet and connect the primary, secondary and grounding wires, which effectively saves the assembly time of the switch cabinet; the product is also simpler to inspect and maintain, does not require regular maintenance, and extends its service life. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the internal structure of the multi-winding, large-capacity, fully insulated voltage transformer of this utility model;

[0021] Figure 2 This is a schematic diagram of the external structure of the multi-winding, large-capacity, fully insulated voltage transformer of this utility model;

[0022] Figure 3 for Figure 2 The left view;

[0023] Figure 4 for Figure 2 Top view;

[0024] Figure 5 This is a schematic diagram of the structure of the primary support in this utility model;

[0025] Figure 6 for Figure 5 The left view;

[0026] Figure 7 for Figure 5 Top view.

[0027] In the diagram: 1-Iron core; 2-Secondary winding; 3-Primary winding; 4-Insulating frame; 5-Base plate; 6-Secondary terminal block; 7-Secondary terminal; 8-Terminal protection cover; 9-Main insulator; 10-Primary high voltage terminal; 11-Skirt; 12-Primary support; 13-Voltage transformer body; 14-Boss; 15-Grounding terminal; 16-Metal round rod; 17-Metal conductive sheet. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] See Figures 1 to 7 As shown, this utility model provides a multi-winding, large-capacity, fully insulated voltage transformer, including a base plate 5 and a main insulator 9 disposed on the base plate 5. The main insulator 9 encloses a transformer body 13 and two primary supports 12 connected to the transformer body 13. The transformer body 13 includes an iron core 1, secondary windings 2 and primary windings 3. Multiple sets of secondary windings 2 are wound around the outside of the iron core 1, and primary windings 3 are wound around the outside of the multiple sets of secondary windings 2. Two primary insulating posts are provided on the top of the main insulator 9, and two primary high-voltage terminals 10 are respectively embedded on the top of the two primary insulating posts. The two primary high-voltage terminals 10 are respectively connected to the two primary supports 12. A secondary terminal block 7 is provided at the lower front part of the main insulator 9.

[0030] See Figures 5 to 7 As shown in the embodiment of this utility model, the primary support 12 includes a metal conductive sheet 17 and a metal rod 16 welded to the middle of the top of the metal conductive sheet 17. The metal conductive sheet 17 has an arc-shaped structure and is closely fitted with the outer diameter of the coil of the primary winding 3. Under long-term overvoltage conditions, it will not suffer insulation breakdown damage. The upper end of the metal rod 16 is connected to the primary high-voltage terminal 10.

[0031] Preferably, the metal rod 16 has an L-shaped structure, and its upper part is housed within the primary insulating column. The outer surface of the primary insulating column is provided with multiple arc-shaped skirts of varying sizes to ensure smooth connection with the high-voltage electrical system equipment, increase the insulation level, and ensure that no flashover voltage occurs; the lower part of the primary insulating column transitions to the transversely smooth cylindrical surface of the main insulator 9.

[0032] In this embodiment of the invention, the outer side of the secondary winding 2 portion of the iron core 1 is wrapped with an iron core insulation layer, and multiple sets of secondary windings 2 are wound on the outer side of the iron core insulation layer. PMP composite paper insulation is added between the layers of the secondary windings 2. A layer of semi-conductive crepe paper is half-lapped on the outer side of the secondary windings 2. The primary winding 3 is wound on an insulating frame 4. A silicone strip is wrapped around each of the two circular ends of the insulating frame 4 and fixed with double-sided tape. A whole sheet of semi-conductive crepe paper is wrapped inside the insulating frame 4. Semi-conductive crepe paper, shaped copper foil, and multiple layers of DMD composite paper are arranged on the outer side of the insulating frame 4. The outer side of the primary winding 3 is wrapped with shaped copper foil, and the metal conductive sheet 17 is welded to the shaped copper foil. A layer of semi-conductive crepe paper is wrapped around the outer side of the metal conductive sheet 17 and the shaped copper foil to form a high-voltage shielding layer.

[0033] Specifically, the core insulation layer is formed by a layer of insulating paperboard and multiple layers of PMP composite paper; the low-voltage shielding layer is semi-conductive crepe paper; the inner shielding layer is formed by adding a shaped copper foil and semi-conductive crepe paper outside the insulating skeleton 4, with gaps left at the beginning and end of the shaped copper foil.

[0034] Furthermore, the part of the iron core 1 excluding the secondary winding 2 is sequentially stacked from the inside out with a layer of self-adhesive tape insulation, a molded polyurethane board buffer layer, another layer of self-adhesive tape insulation, and an additional molded copper foil or aluminum foil. A layer of semi-conductive crepe paper is then stacked to form a low-voltage shielding layer. A layer of semi-conductive paint is then brushed on both axial sides of the wrapped iron core 1.

[0035] In this embodiment of the invention, the main insulator 9 is an integral structure cast with epoxy resin, ensuring sufficient mechanical strength and preventing degradation. The upper middle part of the main insulator 9 is a horizontal cylindrical shape, with the left and right sides tapering downwards to the bottom of the main insulator 9, forming a stepped vertical plane. The horizontal cylindrical shape and the stepped vertical plane have a rounded transition. The front and rear ends of the main insulator 9 are symmetrical vertical column structures, each including a lower semi-cylinder and an upper semi-frustum. The semi-frustum and semi-cylinder have a rounded transition. Square protrusions are provided on the lower left and right sides of the semi-cylinder to ensure uniform insulation distance. The smooth rounded surfaces at both ends of the main insulator 9 facilitate the smooth sliding off of dust and other contaminants, eliminating the need for maintenance.

[0036] Furthermore, two protrusions 14 are provided on the lower left and right sides of the main insulator 9, and each protrusion 14 is provided with a base plate mounting insert.

[0037] Furthermore, a secondary wiring platform 6 is provided at the lower front end of the main insulator 9, and secondary wiring terminals 7 are set on the secondary wiring platform 6. A wiring protective cover 8 is provided above the secondary wiring platform 6, which can effectively ensure the reliable sealing of the secondary wiring terminals 7. A grounding terminal 15 is provided on the bottom plate 5. The grounding terminal 15 is located on one side of the secondary wiring platform 6 at the lower front end of the main insulator 9, which increases the insulation distance between the product surface and the ground and ensures the safe and reliable operation of the product.

[0038] In this embodiment, the semi-circular metal conductive sheet 17 of the primary support 12 is tightly and securely attached to the outer diameter of the copper foil of the primary winding 3, ensuring that the primary coil is not damaged by continuous overvoltage impacts. It has a high overvoltage resistance capability and can be used in overvoltage protection circuits of power systems. It will not suffer insulation breakdown damage under long-term overvoltage conditions. The primary high voltage terminal 10 is threaded and fastened to the primary support 12, and the nut is locked. The distance can be adjusted during molding to ensure that the distance between the primary winding 3 and the secondary winding 2 is uniform.

[0039] This utility model provides a multi-winding, high-capacity, fully insulated voltage transformer. The manufacturing process is as follows: A layer of insulating paperboard and multiple layers of PMP composite paper are wound around a toroidal iron core 1 to form an iron core insulation layer. Multiple sets of secondary windings 2 are wound outside the iron core insulation layer. PMP composite paper insulation is added between the coil layers of the secondary windings 2. Peninsula corrugated paper is wound around the secondary windings 2 to form a low-voltage shielding layer. A silicone strip is wrapped around each of the two circular ends of an open insulating frame 4 and fixed with double-sided tape. A whole sheet of semi-conductive corrugated paper is wrapped around the inner cavity of the insulating frame 4. The insulating frame 4 is then placed on the outside of the secondary windings 2 with the iron core 1. The iron core 1 and the insulating frame 4 are fixed on a CNC parallel winding machine. A shaped copper foil and semi-conductive corrugated paper are added outside the insulating frame 4, forming an inner shielding layer with the whole sheet of semi-conductive corrugated paper inside the cavity. A layer of DMD insulating paper is then added, and a primary winding 3 is wound. After the primary winding 3 is completed, a shaped copper foil is added, with gaps at both ends. A primary support 12 is formed by welding a metal conductive sheet 17 and an L-shaped metal rod 16 using a welding jig, providing a certain mechanical strength. The semi-circular metal conductive sheet 17 is securely attached to the outer diameter of the primary winding 3 formed copper foil, providing high overvoltage resistance. The metal conductive sheet 17 is reinforced with a layer of polyester fiber tape and then partially overlapped with a layer of semi-conductive crepe paper. The exposed parts of the metal conductive sheet 17 and the L-shaped metal rod 16 are sealed with semi-conductive rubber tape and overlapped with the semi-conductive crepe paper to form a high-voltage shielding layer. Then, a metal hose clamp passes through the outer side of the iron core 1 and between it and the insulation layer of the secondary winding 2, securing the iron core 1 and the clamping parts of the device body with a positioning jig thread. The iron core 1, excluding the secondary winding 2, consists of a partially overlapped layer of self-adhesive tape insulation, a formed polyurethane board buffer layer, and a partially overlapped layer of self-adhesive tape insulation from the inside out. An insulating layer is formed by adding a shaped copper or aluminum foil and a half-layer of semi-conductive crepe paper to form a low-voltage shielding layer. A layer of semi-conductive paint of appropriate width is brushed on both sides of the wrapped iron core 1. Finally, the entire voltage transformer body 13 is formed and fixed in the casting mold. The primary bracket 12 fixes the primary high-voltage terminal 10 in the center, connects the secondary wiring terminal 7, and after adjusting the distance, the insulation is cured by vacuum casting with epoxy resin. It then becomes a main insulator 9 with an integrated structure composed of primary wiring terminal 10, secondary wiring platform 6, etc. Finally, the whole body is installed on the base plate 5.

[0040] The upper middle part of the main insulator 9 of the encapsulated voltage transformer body 13 is a horizontal cylindrical shape, while the front and rear ends are symmetrical vertical columns composed of semi-circular frustums and semi-cylinders with rounded transitions. The two sides of the horizontal cylindrical shape transition downwards with rounded transitions and taper to the bottom, forming a stepped vertical plane to ensure uniform resin insulation thickness. The smooth rounded surfaces at the front and rear ends facilitate the smooth sliding off of dust and other contaminants. The lower part of the semi-cylinder at the front end of the main insulator 9 is provided with symmetrically protruding square bosses to increase the creepage distance between the secondary terminal 7 and the primary winding 3. The secondary terminal block 6 is integrally cast with the main insulator 9. The secondary terminal block 6 is located directly below the front of the main insulator 9, and a wiring protective cover 8 is provided above the secondary terminal block 6 to effectively ensure reliable sealing of the secondary terminal block and prevent electricity theft. The base plate 5 is provided with a grounding terminal 15, which is located on one side of the front end of the main insulator 9 for easy grounding by the user and to ensure reliable grounding. A base plate mounting insert is provided below the main insulator 9. The mounting insert is located inside the semi-cylindrical protrusions 14 on both sides. The optimized structural design further reduces the overall weight and increases the insulation distance between the product surface and the ground.

[0041] When in use, simply fix the base plate 5 of the transformer in the switch cabinet, and then connect the primary terminal 10 and the secondary terminal 7 and grounding terminal 15 on the secondary terminal block 6. The installation of the multi-winding large-capacity fully insulated voltage transformer is completed, which can effectively save the assembly time of the switch cabinet.

[0042] This utility model provides a multi-winding, high-capacity, fully insulated voltage transformer, a new generation of voltage transformer specifically designed for switchgear. The product is manufactured using epoxy resin vacuum casting insulation and is primarily used in power systems or electrical control systems as a line measurement and protection device. The product features small size, flexible installation, reliable insulation, multiple windings, large capacity, and resistance to overvoltage surges, making it perfectly suited for use in my country's power systems or electrical control systems, thus improving the overall manufacturing level of electrical control system equipment.

[0043] The above description is merely an embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, extensions, etc., made within the spirit and principles of this utility model are included within the scope of protection of this utility model.

Claims

1. A multi-winding, high-capacity, fully insulated voltage transformer, comprising a base plate (5) and a main insulator (9) disposed on the base plate (5), characterized in that, The main insulator (9) encloses a voltage transformer body (13) and two primary supports (12) connected to the voltage transformer body (13). The voltage transformer body (13) includes an iron core (1), a secondary winding (2) and a primary winding (3). Multiple sets of secondary windings (2) are wound around the outside of the iron core (1), and primary windings (3) are wound around the outside of the multiple sets of secondary windings (2). Two primary insulating pillars are provided on the top of the main insulator (9), and two primary high-voltage terminals (10) are respectively embedded on the top of the two primary insulating pillars. The two primary high-voltage terminals (10) are respectively connected to the two primary supports (12). A secondary terminal (7) is provided at the lower front part of the main insulator (9).

2. The multi-winding, large-capacity, fully insulated voltage transformer according to claim 1, characterized in that, The primary support (12) includes a metal conductive sheet (17) and a metal rod (16) connected to the top of the metal conductive sheet (17). The metal conductive sheet (17) has an arc-shaped structure and is closely fitted with the outer diameter of the coil of the primary winding (3). The upper end of the metal rod (16) is connected to the primary high voltage terminal (10).

3. The multi-winding, large-capacity, fully insulated voltage transformer according to claim 2, characterized in that, The metal rod (16) has an L-shaped structure, and its upper part is housed within the primary insulating column.

4. The multi-winding, large-capacity, fully insulated voltage transformer according to claim 2, characterized in that, The outer side of the portion of the iron core (1) around which the secondary winding (2) is wound is wrapped with an iron core insulation layer. Multiple sets of the secondary winding (2) are wound on the outer side of the iron core insulation layer. PMP composite paper insulation is added between the layers of the secondary winding (2). A layer of semi-conductive crepe paper is half-lapped on the outer side of the secondary winding (2). The primary winding (3) is wound on an insulating frame (4). A silicone strip is wrapped around each of the two circular ends of the insulating frame (4) and fixed with double-sided tape. The inner cavity of the insulating frame (4) is wrapped with a whole sheet of semi-conductive crepe paper. The outer side of the insulating frame (4) is provided with semi-conductive crepe paper, shaped copper foil and multi-layer DMD composite paper. The outer side of the primary winding (3) is wrapped with shaped copper foil. The metal conductive sheet (17) of the primary support (12) is in close contact with the shaped copper foil. The outer side of the metal conductive sheet (17) is wrapped with a layer of semi-conductive crepe paper. The exposed parts of the metal conductive sheet (17) and the metal rod (16) folded into an L shape are sealed with semi-conductive rubber tape and superimposed with the semi-conductive crepe paper to form a high-voltage shielding layer.

5. The multi-winding, large-capacity, fully insulated voltage transformer according to claim 4, characterized in that, The core insulation layer is formed by a layer of insulating paperboard and multiple layers of PMP composite paper.

6. The multi-winding, large-capacity, fully insulated voltage transformer according to claim 1, characterized in that, The outer surface of the primary insulating column is provided with multiple arc-shaped skirts of varying sizes.

7. The multi-winding, large-capacity, fully insulated voltage transformer according to claim 1, characterized in that, The iron core (1), excluding the secondary winding (2) being wound, consists of a self-adhesive tape insulation layer, a molded polyurethane board buffer layer, a self-adhesive tape insulation layer, a molded copper foil or aluminum foil, and a semi-conductive crepe paper layer forming a low-voltage shielding layer. A layer of semi-conductive paint is then applied to both axial sides of the wrapped iron core (1).

8. The multi-winding, large-capacity, fully insulated voltage transformer according to claim 1, characterized in that, The main insulator (9) is an integral structure cast with epoxy resin. The upper middle part of the main insulator (9) is a horizontal cylindrical shape. The left and right sides of the horizontal cylindrical shape taper downward to the bottom of the main insulator (9) to form a stepped vertical plane. The horizontal cylindrical shape and the stepped vertical plane are connected by an arc. The front and rear ends of the main insulator (9) are symmetrical vertical column structures. The vertical column structure includes a semi-cylinder at the bottom and a semi-circular frustum at the top. The semi-circular frustum and the semi-cylinder are connected by an arc. The lower left and right sides of the semi-cylinder are provided with square protrusions.

9. The multi-winding, large-capacity, fully insulated voltage transformer according to claim 8, characterized in that, The main insulator (9) has two protrusions (14) on the lower left and right sides, and each protrusion (14) has a base plate mounting insert.

10. The multi-winding, large-capacity, fully insulated voltage transformer according to claim 1, characterized in that, The main insulator (9) has a secondary wiring platform (6) at the lower front end, and the secondary wiring terminal (7) is set on the secondary wiring platform (6). A wiring protective cover (8) is installed above the secondary wiring platform (6); a grounding terminal (15) is provided on the base plate (5).

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