A body of an electromagnetic voltage transformer for GIS and a manufacturing method thereof

Abstract

The present invention relates to a body of an electromagnetic voltage transformer for GIS and a manufacturing method thereof, belonging to the technical field of transformers. It includes a base, on which a first clamping member and a second clamping member are installed. The first clamping member and the second clamping member jointly clamp an iron core. An insulating cylinder is sleeved on the iron core, a coil is sleeved on the outer peripheral wall of the insulating cylinder, and a high-voltage shielding cover is arranged on the outer peripheral wall of the coil. The coil and the high-voltage shielding cover adopt an open structure, which is not only convenient for fixing and installation in addition to meeting the high-voltage electric field shielding function of the product; directly using the iron core clamping member to replace the side shielding and bottom shielding structures simplifies the overall structure of the body of the electromagnetic voltage transformer and saves installation space; the potential and electric field strength at the end of the trapezoidal structure coil are very uniform, which can provide sufficient creepage distance for impulse voltage, avoiding the phenomenon of excessive current caused by insufficient creepage distance of the body of the electromagnetic voltage transformer and ensuring the safety requirements of the voltage transformer.

Description

Technical Field

[0001] The present invention relates to the technical field of instrument transformers, and specifically discloses a body of an electromagnetic voltage transformer for GIS and a manufacturing method thereof. Background Art

[0002] GIS is a high-voltage switch cabinet composed of 7 high-voltage electrical appliances, namely circuit breaker, busbar, disconnector, voltage transformer, current transformer, lightning arrester, and bushing, and its full name is fully insulated and enclosed metal switchgear. The voltage transformer can convert the high voltage in the power grid into low voltage for facilitating the monitoring and measurement of high-voltage equipment. The voltage transformer is a step-down transformer with small capacity, small volume, and large voltage ratio. Its basic working principle, structure, and connection method are the same as those of a transformer, and the main difference is that the capacity of the voltage transformer is very small, usually only dozens to hundreds of volt-amperes.

[0003] The utility model patent with the authorization announcement number: CN217768098U discloses an electromagnetic voltage transformer, which includes a bottom case, an iron core, and an adapter base. The top of the bottom case is provided with an upper case, and a partition is provided between the bottom case and the upper case; the iron core penetrates through the partition, the lower part of the iron core is arranged in the bottom case, and at the same time, the upper part of the iron core is arranged in the upper case; the top of the upper case is provided with a top case, and two of the adapter bases are installed inside the top case.

[0004] The body structure of the electromagnetic voltage transformer in the disclosed patented technology is complex and the assembly difficulty is relatively large, which is not applicable to GIS; moreover, the coil used is of a rectangular structure, and the creepage distance along the surface of the winding of the rectangular structure coil is relatively small. When the power frequency voltage creepage distance is sufficient, the impulse voltage creepage distance is insufficient, which will cause the current in the circuit to be too large, increase the energy consumption of the voltage transformer, and cause energy waste; generally, it will make other components in GIS work abnormally, thus affecting the normal operation of GIS; in serious cases, it is extremely easy to cause tripping and fire, and cannot meet the safety requirements of the voltage transformer. Summary of the Invention

[0005] In view of the current disadvantages of the complex structure and poor safety performance of the electromagnetic voltage transformer, the present invention provides a body of an electromagnetic voltage transformer for GIS and a manufacturing method thereof.

[0006] To achieve the above object, in the first aspect, the present invention provides the following technical solutions:

[0007] A body of an electromagnetic voltage transformer for GIS, comprising a base, on which a first clamping member and a second clamping member are installed. The first clamping member and the second clamping member jointly clamp an iron core. An insulating cylinder is sleeved on the iron core. A coil is sleeved on the outer peripheral wall of the insulating cylinder. A high-voltage shielding cover is arranged on the outer peripheral wall of the coil. The high-voltage shielding cover includes a first high-voltage sleeve ring closely attached to the outer peripheral wall of the coil. A second high-voltage sleeve ring is sleeved on the outer peripheral wall of the first high-voltage sleeve ring. Ring ears are arranged on both sides of the second high-voltage sleeve ring, and a ferrule closely attached to the outer peripheral wall of the second high-voltage sleeve ring is arranged in the ring ears. The coil and the high-voltage shielding cover of the body of the electromagnetic voltage transformer adopt an open structure. In addition to meeting the shielding effect on the high-voltage electric field, this structure is more convenient for fixing and installation. By improving the clamping member structure of the iron core and using the first clamping member and the second clamping member to clamp the iron core inside, the original side shielding and bottom shielding structures of the body of the electromagnetic voltage transformer are combined with the clamping member structure, and the iron core clamping members directly replace the side shielding and bottom shielding structures, thereby simplifying the overall structure of the body of the electromagnetic voltage transformer and saving installation space. By splitting the high-voltage shielding cover into a first high-voltage sleeve ring and a second high-voltage sleeve ring and stably fixing it with a ferrule, the electromagnetic shielding ability of the high-voltage shielding cover is enhanced and electromagnetic interference is reduced.

[0008] Preferably, the coil is a trapezoidal structure coil, and the coil is composed of copper wire and diamond film. The trapezoidal structure coil decreases step by step for each layer, reducing the requirement for the insulation distance from the inner wall of the iron core and saving raw materials. Moreover, the potential and electric field intensity at the end of the trapezoidal structure coil are very uniform, which can provide sufficient creepage distance for impulse voltage, avoiding the phenomenon of excessive current caused by insufficient creepage distance of the body of the electromagnetic voltage transformer and ensuring the safety requirements of the voltage transformer.

[0009] Preferably, the ferrule is provided with an opening, and symmetrically arranged buckle supports are installed at the opening of the ferrule. The symmetrically arranged buckle supports are fixedly connected together through a bolt structure. Under the action of the bolt structure, the symmetrically arranged buckle supports can fasten the ferrule on the outer peripheral wall of the second high-voltage sleeve ring. And the tightness of the ferrule can be adjusted by adjusting the bolt structure connecting the buckle supports, improving the adaptability between the ferrule and the high-voltage shielding cover. By setting the ferrule, the stability of the high-voltage shielding cover can be enhanced, ensuring that the high-voltage shielding cover will not loosen or fall off, and enhancing the stability of the body of the electromagnetic voltage transformer during operation.

[0010] Preferably, a clamping plate is arranged between the ferrule and the second high-voltage sleeve ring. The clamping plate is fixedly connected to the ferrule through a bolt structure, and both ends of the clamping plate are arranged in the ring ears. The wire in GIS can be connected to the bolt structure arranged in the clamping plate, and the coil is then connected to the clamping plate through the wire, thereby realizing the interconnection between the coil and the circuit in GIS.

[0011] Preferably, connecting supports are installed on the tops of the first clamping member and the second clamping member, and the connecting supports are fixedly connected to the insulating cylinder. By providing the connecting supports, the first clamping member and the second clamping member can be firmly connected to the insulating cylinder, enabling the first clamping member, the second clamping member and the insulating cylinder to form an integral shielding structure, ensuring the normal operation of the body of the electromagnetic voltage transformer; and fully simplifying the installation structure of the body of the electromagnetic voltage transformer and reducing the installation volume of the body of the electromagnetic voltage transformer.

[0012] Preferably, locking bolts for connection are provided at both the top end and the bottom end of the first clamping member. The locking bolt at the top end passes through the gap between the iron core and the insulating cylinder and is fixedly connected to the second clamping member, and the locking bolt at the bottom end is arranged below the iron core and is fixedly connected to the second clamping member. By using the locking bolts, the first clamping member and the second clamping member can be fastened together, ensuring the clamping degree of the iron core and the stability of the body of the electromagnetic voltage transformer.

[0013] On the other hand, the present invention also provides a method for manufacturing the body of an electromagnetic voltage transformer for GIS, comprising the following steps:

[0014] S1, performing vacuum annealing on the iron core and impregnating it with epoxy resin, and casting the iron core and the epoxy resin into an integral body;

[0015] S2, putting the copper wire and the diamond film into a full-automatic winding machine, and winding them into a trapezoidal structure coil symmetrical on both sides by the full-automatic winding machine, so that the copper wire, the diamond film and the copper wire are arranged in layers;

[0016] S3, sleeving the coil on the outer peripheral wall of the insulating cylinder, closely attaching the first high-voltage collar to the outer peripheral wall of the coil, pressing the second high-voltage collar against the first high-voltage collar, placing a clamping plate on the outer peripheral wall of the second high-voltage collar, placing a hoop above the clamping plate, fastening the clamping plate and the hoop by a bolt structure, and fixing and locking the hoop by using a buckle support and a bolt structure;

[0017] S4, sleeving the insulating cylinder on the iron core, using the first clamping member and the second clamping member to jointly clamp the iron core, fixedly connecting the first clamping member and the second clamping member to the insulating cylinder through a connecting support, and firmly connecting the first clamping member and the second clamping member by using a locking bolt;

[0018] S5, fixedly installing the first clamping member and the second clamping member on the base, and installing the base in the GIS.

[0019] From the above technical solutions, it can be seen that the present invention has the following advantages:

[0020] 1. The coil and the high-voltage shielding cover of the present invention adopt an open structure. In addition to meeting the high-voltage electric field shielding function of the product, this structure is more convenient for fixing and installation. By improving the clamping structure of the iron core, the first clamping piece and the second clamping piece are used to clamp the iron core inside, so that the original side shielding and bottom shielding structures of the electromagnetic voltage transformer body are combined with the clamping structure design, and the iron core clamping piece is directly used to replace the side shielding and bottom shielding structures, thereby simplifying the overall structure of the electromagnetic voltage transformer body and saving installation space;

[0021] 2. The coil of the present invention is designed as a trapezoidal structure coil, so that the potential and electric field strength at the end of the coil are very uniform, which can provide sufficient impulse voltage creepage distance, avoid the phenomenon of excessive current caused by insufficient impulse voltage creepage distance of the electromagnetic voltage transformer body, and ensure the safety requirements of the voltage transformer body;

[0022] 3. The coil of the present invention improves the impulse gradient voltage distribution along the coil, can withstand multiple lightning strikes, and effectively improves the lightning impulse resistance performance of the electromagnetic voltage transformer body;

[0023] 4. By setting the hoop, the present invention can effectively enhance the stability of the high-voltage shielding cover, ensure that the high-voltage shielding cover will not loosen or fall off, and enhance the stability of the electromagnetic voltage transformer body during operation.

[0024] In addition, the design structure of the present invention is simple, convenient for disassembly and assembly, safe and reliable, and has a very wide application prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the present invention, the drawings required for description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0026] Figure 1 It is a schematic diagram of the overall structure of the electromagnetic voltage transformer body in the specific embodiment of the present invention.

[0027] Figure 2 It is a schematic diagram of the connection structure of the first clamping piece and the second clamping piece in the specific embodiment of the present invention.

[0028] Figure 3 It is a schematic diagram of the coil installation structure in the specific embodiment of the present invention.

[0029] Figure 4 It is a schematic diagram of the insulating cylinder structure in the specific embodiment of the present invention.

[0030] Figure 5 It is an exploded view of the high-voltage shielding cover structure in the specific embodiment of the present invention.

[0031] Figure 6 Schematic diagram of the iron core structure of the specific embodiment of the present invention.

[0032] Figure 7 Schematic diagram of the connecting support structure of the specific embodiment of the present invention.

[0033] Figure 8 Cross-sectional view of the coil structure of the specific embodiment of the present invention.

[0034] Figure 9 is Figure 8 Enlarged view of the structure at A in

[0035] In the figure: 1. Base, 2. First clamping piece, 3. Second clamping piece, 4. Iron core, 5. Insulating cylinder, 6. Coil, 601. Copper wire, 602. Diamond film, 7. High-voltage shielding cover, 701. First high-voltage collar, 702. Second high-voltage collar, 703. Ring ear, 704. Sleeve hoop, 705. Buckle support, 706. Cardboard, 8. Connecting support, 9. Locking bolt. Specific embodiment

[0036] In order to make the objectives, features, and advantages of the present invention more obvious and understandable, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the specific embodiments of the present invention. Obviously, the embodiments described below are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in this patent, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of this patent.

[0037] Please refer to the attached Figures 1-9 , this specific embodiment provides a body of an electromagnetic voltage transformer for GIS, including a base 1, a first clamping piece 2 and a second clamping piece 3 are installed on the base 1, the first clamping piece 2 and the second clamping piece 3 jointly clamp an iron core 4, an insulating cylinder 5 is sleeved around the iron core 4, a coil 6 is sleeved on the outer peripheral wall of the insulating cylinder 5, and a high-voltage shielding cover 7 is arranged on the outer peripheral wall of the coil 6. The coil 6 and the high-voltage shielding cover 7 of the body of the electromagnetic voltage transformer adopt an open structure. In addition to meeting the high-voltage electric field shielding function of the product, this structure is more convenient for fixing and installation; by improving the clamping piece structure of the iron core 4 and using the first clamping piece 2 and the second clamping piece 3 to clamp the iron core 4 inside, the original side shielding and bottom shielding structures of the body of the electromagnetic voltage transformer are combined with the clamping piece structure, and the iron core clamping piece is directly used to replace the side shielding and bottom shielding structures, thereby simplifying the overall structure of the body of the electromagnetic voltage transformer and saving installation space.

[0038] Among them, the coil 6 is a trapezoidal structure coil, and the coil 6 is composed of a copper wire 601 and a diamond-shaped thin film 602. The trapezoidal structure coil decreases step by step for each layer, reducing the requirement for the insulation distance from the inner wall of the iron core 4 and saving raw materials; moreover, the potential and electric field strength at the end of the trapezoidal structure coil are very uniform, which can provide sufficient creepage distance for the impulse voltage, avoiding the phenomenon of excessive current caused by insufficient creepage distance of the impulse voltage in the body of the electromagnetic voltage transformer, and ensuring the safety requirements of the body of the voltage transformer.

[0039] The high-voltage shielding cover 7 includes a first high-voltage collar 701 closely attached to the outer peripheral wall of the coil. A second high-voltage collar 702 is sleeved on the outer peripheral wall of the first high-voltage collar 701. Ring ears 703 are arranged on both sides of the second high-voltage collar 702, and a ferrule 704 closely attached to the outer peripheral wall of the second high-voltage collar 702 is arranged in the ring ears 703. By splitting the high-voltage shielding cover into the first high-voltage collar and the second high-voltage collar and stably fixing them using the ferrule, the electromagnetic shielding ability of the high-voltage shielding cover is enhanced, and the electromagnetic interference is reduced.

[0040] The ferrule 704 is provided with an opening, and symmetrically arranged buckle supports 705 are installed at the opening of the ferrule 704. The symmetrically arranged buckle supports 705 are fixedly connected together through a bolt structure. Under the action of the bolt structure connection, the symmetrically arranged buckle supports 705 can fasten the ferrule 704 on the outer peripheral wall of the second high-voltage collar 702; and the tightness of the ferrule 704 can be adjusted by adjusting the bolt structure connected to the buckle supports 705, that is, by rotating the nut in the bolt structure inwards or outwards, thereby improving the adaptability of the ferrule 704 to the high-voltage shielding cover 7. By setting the ferrule 704, the stability of the high-voltage shielding cover 7 can be enhanced, ensuring that the high-voltage shielding cover 7 will not loosen or fall off, and enhancing the stability of the body of the electromagnetic voltage transformer during operation.

[0041] A clamping plate 706 is arranged between the ferrule 704 and the second high-voltage collar 702. The clamping plate 706 is fixedly connected to the ferrule 704 through a bolt structure, and both ends of the clamping plate 706 are arranged in the ring ears 703. Both the first high-voltage collar 701 and the second high-voltage collar 702 are provided with through holes. The coil 6 can be connected to the clamping plate 706 after the wire passes through the first high-voltage collar 701 and the second high-voltage collar 702. The wire in the GIS can be connected to the bolt structure arranged in the clamping plate 706, thereby realizing the interconnection between the coil 6 and the circuit in the GIS.

[0042] A connecting support 8 is installed on the top of both the first clamping member 2 and the second clamping member 3, and the connecting support 8 is fixedly connected to the insulating cylinder 5. The connecting support 8 is provided with through holes facilitating the installation of bolts. The connecting support 8 is fixed to the tops of the first clamping member 2 and the second clamping member 3 by bolts. The connecting support 8 is further provided with clamping posts facilitating insertion. The clamping posts of the connecting support 8 can be stuck in the clamping holes of the insulating cylinder 5, so that the connecting support 8 and the insulating cylinder 5 form a firmly connected integral structure. By providing the connecting support 8, the first clamping member 2 and the second clamping member 3 can be firmly connected to the insulating cylinder 5, enabling the first clamping member 2, the second clamping member 3 and the insulating cylinder 5 to form an integral shielding structure, ensuring the normal operation of the body of the electromagnetic voltage transformer; and fully simplifying the installation structure of the body of the electromagnetic voltage transformer and reducing the installation volume of the body of the electromagnetic voltage transformer.

[0043] Locking bolts 9 for connection are provided at both the top end and the bottom end of the first clamping member 2. The locking bolt 9 at the top end passes through the gap between the iron core 4 and the insulating cylinder 5 and is fixedly connected to the second clamping member 3. The locking bolt 9 at the bottom end is arranged below the iron core 4 and is fixedly connected to the second clamping member 3. By using the locking bolts 9, the first clamping member 2 and the second clamping member 3 can be fastened together, ensuring the clamping degree of the iron core 4 and the stability of the body of the electromagnetic voltage transformer.

[0044] In the above text, an embodiment of the body of an electromagnetic voltage transformer for GIS is described in detail. Based on the body of the electromagnetic voltage transformer for GIS described in the above embodiment, the embodiment of the present invention also provides a manufacturing method corresponding to the body of the electromagnetic voltage transformer for GIS, including the following steps:

[0045] S1, performing vacuum annealing on the iron core 4 and impregnating it with epoxy resin, and casting the iron core 4 and the epoxy resin into a whole; the magnetic circuit of the iron core 4 made by this method is coherent. Compared with the laminated iron core with a through-core screw structure mostly used currently, the no-load loss is reduced by 7%-10%; the no-load current can be reduced by 65%-85%, enabling the iron core 4 to have good heat dissipation and thermal shock performance. Since the no-load current is small and the no-load loss is low, the heat generation of the iron core is also relatively low;

[0046] S2, putting the copper wire 601 and the diamond film 602 into a full-automatic winding machine and winding them into a trapezoidal structure coil symmetrical on both sides, so that the copper wire 601 and the diamond film 602 are arranged in layers; the thickness of the trapezoidal structure coil is reduced by 65% compared with the rectangular structure coil, and the error performance is improved by 25%-30% compared with the rectangular structure coil;

[0047] S3. Set the coil 6 on the outer peripheral wall of the insulating cylinder 5. Press the first high-voltage collar 701 against the outer peripheral wall of the coil 6. Press the second high-voltage collar 702 against the first high-voltage collar 701. Place the clamping plate 706 on the outer peripheral wall of the second high-voltage collar 702. Place the ferrule 704 above the clamping plate 706. Fasten the clamping plate 706 and the ferrule 704 with a bolt structure. Fix and lock the ferrule 704 using the buckle support 705 and the bolt structure.

[0048] S4. Set the insulating cylinder 5 on the iron core 4. Use the first clamping piece 2 and the second clamping piece 3 to jointly clamp the iron core 4. Fix and connect the first clamping piece 2 and the second clamping piece 3 to the insulating cylinder 5 through the connecting support 8. Fasten and connect the first clamping piece 2 and the second clamping piece 3 using the locking bolt 9.

[0049] S5. Fix and install the first clamping piece 2 and the second clamping piece 3 on the base 1. Install the base 1 in the GIS.

[0050] The present invention has redesigned the body of the voltage transformer for GIS, simplified the structure and reduced the volume on the basis of meeting the requirements of insulation distance, thereby reducing the influence of the body on the outer diameter of the entire electromagnetic voltage transformer body product for GIS. It can not only reduce the cost of the product, but also reduce the assembly difficulty and improve the assembly efficiency.

[0051] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. The body of an electromagnetic voltage transformer for GIS, comprising a base (1), characterized in that, A first clamping member (2) and a second clamping member (3) are mounted on a base (1). The first clamping member (2) and the second clamping member (3) jointly clamp an iron core (4). An insulating cylinder (5) is sleeved around the iron core (4). A coil (6) is sleeved on the outer peripheral wall of the insulating cylinder (5). A high-voltage shielding cover (7) is provided on the outer peripheral wall of the coil (6). The high-voltage shielding cover (7) includes a first high-voltage collar (701) closely attached to the outer peripheral wall of the coil. A second high-voltage collar (702) is sleeved on the outer peripheral wall of the first high-voltage collar (701). Ring ears (703) are provided on both sides of the second high-voltage collar (702). A ferrule (704) closely attached to the outer peripheral wall of the second high-voltage collar (702) is provided in the ring ear (703). A clamping plate (706) is provided between the ferrule (704) and the second high-voltage collar (702). The clamping plate (706) is fixedly connected to the ferrule (704) through a bolt structure. Both ends of the clamping plate (706) are arranged in the ring ear (703). Connection supports (8) are mounted on the tops of both the first clamping member (2) and the second clamping member (3). The connection supports (8) are fixedly connected to the insulating cylinder (5). Locking bolts (9) for connection are provided at both the top end and the bottom end of the first clamping member (2). The locking bolt (9) at the top end passes through the gap between the iron core (4) and the insulating cylinder (5) and is fixedly connected to the second clamping member (3). The locking bolt (9) at the bottom end is arranged below the iron core (4) and is fixedly connected to the second clamping member (3).

2. The body of an electromagnetic voltage transformer for GIS according to claim 1, characterized in that, The coil (6) is a trapezoidal structure coil. The coil (6) is composed of a copper wire (601) and a diamond film (602).

3. The body of an electromagnetic voltage transformer for GIS according to claim 1, characterized in that, The ferrule (704) is provided with an opening. Symmetrically arranged buckle supports (705) are mounted at the opening of the ferrule (704). The symmetrically arranged buckle supports (705) are fixedly connected together through a bolt structure.

4. A manufacturing method of the body of an electromagnetic voltage transformer for GIS as described in any one of claims 1-3, characterized in that, It includes the following steps: S1, subject the iron core (4) to vacuum annealing and impregnate it with epoxy resin, and cast the iron core (4) and the epoxy resin into an integral body; S2, put the copper wire (601) and the diamond film (602) into a full-automatic winding machine, and wind them into a trapezoidal structure coil with symmetric sides by the full-automatic winding machine, so that the copper wire (601) and the diamond film (602) are arranged in layers; S3, sleeve the coil (6) on the outer peripheral wall of the insulating cylinder (5), closely attach the first high-voltage collar (701) to the outer peripheral wall of the coil (6), press the second high-voltage collar (702) against the first high-voltage collar (701), place the clamping plate (706) on the outer peripheral wall of the second high-voltage collar (702), place the ferrule (704) above the clamping plate (706), fasten the clamping plate (706) and the ferrule (704) through a bolt structure, and use the buckle support (705) and the bolt structure to fixedly lock the ferrule (704); S4. Sheath the insulating cylinder (5) on the iron core (4), use the first clamping member (2) and the second clamping member (3) to jointly clamp the iron core (4), fixedly connect the first clamping member (2) and the second clamping member (3) to the insulating cylinder (5) through the connecting support (8), use the locking bolt (9) to tightly connect the first clamping member (2) and the second clamping member (3), and tighten the nuts at both ends of the locking bolt (9) to fasten the locking bolt (9); S5. Fix and install the first clamping member (2) and the second clamping member (3) on the base (1), and install the base (1) in the GIS.

Images