Impedance balance compensation high-precision current transformer

Abstract

The utility model discloses an impedance balance compensation high-precision current transformer. Comprising a fixed plate, a semi-circular fixed lower shell with a cavity, a semi-circular detachable upper shell with a cavity, a fixed iron core and a detachable iron core, wherein the semi-circular fixed lower shell with the cavity is fixedly connected to the fixed plate, the semi-circular detachable upper shell with the cavity is mounted above the fixed lower shell, and the fixed iron core and the detachable iron core are fixedly mounted in the fixed lower shell and the detachable upper shell respectively. And the opposite ends of the fixed iron core and the detachable iron core are close and attached to form a complete circular ring structure. The detachable fixed lower shell and the detachable upper shell are arranged, installation can be completed without breaking a high-voltage wire of a main coil during use, wiring is convenient, meanwhile, the opposite ends of the fixed lower shell and the detachable upper shell are open, and the fixed iron core and the detachable iron core in the fixed lower shell and the detachable upper shell can be spliced without shielding. Therefore, the purposes of greatly reducing magnetic leakage and improving the magnetic conduction effect are achieved, the directly generated current error is reduced, and the precision is improved.

Description

Technical Field

[0001] This utility model relates to the field of current transformer technology, specifically to a high-precision current transformer with impedance balance compensation. Background Technology

[0002] Impedance-balanced compensation current transformer is a type of current transformer that combines impedance balance compensation technology. Based on the principle of electromagnetic induction, the main coil current generates a magnetic field, and the secondary coil induces a current. Through optimized structural design and additional functional modules, the circuit impedance parameters are adjusted to compensate for errors caused by load changes, thereby improving measurement accuracy and stability. It is widely used in power systems, industrial automation, smart grids and other fields.

[0003] Impedance-balanced compensation current transformers are mainly divided into fixed current transformers and switchable current transformers according to their shape. The main coil of a fixed current transformer, i.e., the high-voltage conductor, needs to pass through a central perforation. However, since there are no gaps around the perforation in a fixed current transformer, the high-voltage conductor must be disconnected to pass through the perforation and then reconnected. In many cases, for structural integrity and safety reasons, it is inconvenient to disconnect and reconnect the high-voltage conductor. Therefore, the switchable current transformer easily solves this installation problem by having two movable hinged parts that open and close onto the high-voltage conductor. Thus, the switchable current transformer is more convenient in terms of installation.

[0004] Most open-type current transformers on the market are essentially independent of each other, connected only by the hinge. The iron cores inside the two outer shells are independently packaged, so the two iron cores are not physically connected. Although the magnetic field lines that generate the magnetic field can close, the large gap between the two iron cores inevitably leads to a large leakage magnetic field. This means that the influence of leakage magnetic field needs to be considered during measurement, making data processing more complex and troublesome, and causing many inconveniences. Utility Model Content

[0005] To address the shortcomings of existing technologies, this utility model provides a high-precision current transformer with impedance balance compensation, which solves the problem of severe magnetic leakage caused by the large gap between the two iron cores in the currently available open-type impedance balance compensation current transformers.

[0006] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0007] An impedance-balanced compensation high-precision current transformer includes a fixed plate, a cavity semi-circular annular fixed lower shell fixedly connected to the fixed plate, a cavity semi-circular detachable upper shell installed above the fixed lower shell, and a fixed iron core and a detachable iron core respectively fixedly installed inside the fixed lower shell and the detachable upper shell. The opposite ends of the fixed lower shell and the detachable upper shell are open, and the fixed iron core and the detachable iron core are both semi-circular and their opposite ends are close to each other to form a complete ring structure.

[0008] The left and right halves of the fixed iron core are each wound with a set of fixed coils. The opposite ends of the two sets of fixed coils are respectively connected to two connecting pipes fixed inside the lower part of the fixed shell. The front of the fixed shell is provided with screw terminals that are threaded to the connecting pipes. The upper ends of the two sets of fixed coils are respectively fixedly connected to two pipe clamps fixed at both ends of the fixed shell. A ring of retaining strips is provided on the outer walls of both ends of the fixed shell.

[0009] The surface of the detachable iron core is wound with a set of detachable coils. The detachable coils and the two sets of fixed coils are wound in the same spiral direction on the detachable iron core and the fixed iron core respectively. Both ends of the detachable coils are connected to two terminal plugs fixed at both ends of the detachable upper shell. The two terminal plugs are respectively inserted into two pipe clamps. The outer walls of both ends of the detachable upper shell are provided with a groove for engaging with the locking strip.

[0010] Both ends of the fixed lower shell and the detachable upper shell are provided with connecting ears, and fastening bolts and fastening nuts are installed between the connecting ears on the fixed lower shell and the detachable upper shell.

[0011] Preferably, the fixed iron core and the detachable iron core are the same in shape and size and are arranged symmetrically at the top and bottom. The interior of the detachable upper shell and the fixed lower shell are respectively provided with fixing grooves for installing and fixing the detachable iron core and the fixed iron core.

[0012] Preferably, the winding pitch of the fixed coil and the detachable coil are equal.

[0013] Preferably, both the fixed lower shell and the detachable upper shell have internal limit buckles, and the wiring pipe, pipe clamp and wiring plug are all fixed by the limit buckles.

[0014] Preferably, the pipe clamp is flared in shape with its opening facing upward and vertically arranged, and an expansion joint is provided on the lower half of its side wall. The pipe clamp is inserted into the wiring plug with an interference fit.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] This invention features a detachable fixed lower shell and a detachable upper shell, allowing for installation without disconnecting the high-voltage wires of the main coil, making wiring more convenient. Furthermore, both the fixed lower shell and the detachable upper shell are open at opposite ends, allowing the fixed and openable iron cores inside to be joined without obstruction. This significantly reduces magnetic leakage and improves magnetic conductivity, minimizing direct current errors and increasing accuracy. It also solves the problem of severe magnetic leakage caused by the large gap between the two iron cores in currently available open-type impedance balance compensation current transformers. Attached Figure Description

[0017] Figure 1 This is a front view of the present utility model;

[0018] Figure 2 This is a side view of the present invention;

[0019] Figure 3 This is a schematic diagram of the internal structure of this utility model;

[0020] Figure 4 This is a schematic diagram of the internal structure of the detachable upper shell of this utility model;

[0021] Figure 5 This is a schematic diagram of the internal structure of the fixed lower shell of this utility model;

[0022] Figure 6 This is a schematic diagram of the internal structure of the pipe clamp of this utility model;

[0023] Figure 7 This is a cross-sectional view of the pipe clamp of this utility model.

[0024] In the diagram: 1. Fixing plate; 2. Fixing lower shell; 3. Removable upper shell; 4. Fixing iron core; 5. Removable iron core; 6. Fixing coil; 7. Connecting pipe; 8. Screw terminal; 9. Pipe clamp; 10. Locking strip; 11. Removable coil; 12. Connecting plug; 13. Locking slot; 14. Connecting ear; 15. Fastening bolt; 16. Fastening nut; 17. Fixing groove; 18. Limit buckle. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0026] like Figure 1-7As shown, this utility model provides a technical solution: a high-precision current transformer with impedance balance compensation, including a fixed plate 1, a cavity semi-circular ring-shaped fixed lower shell 2 fixedly connected to the fixed plate 1, a cavity semi-circular ring-shaped detachable upper shell 3 installed above the fixed lower shell 2, and a fixed iron core 4 and a detachable iron core 5 respectively fixedly installed inside the fixed lower shell 2 and the detachable upper shell 3, with the opposite ends of the fixed lower shell 2 and the detachable upper shell 3 being open;

[0027] Both the fixed iron core 4 and the detachable iron core 5 are semi-circular rings and their opposite ends are close together to form a complete ring structure. The fixed iron core 4 and the detachable iron core 5 have the same shape and size and are arranged symmetrically at the top and bottom. The interior of the detachable upper shell 3 and the fixed lower shell 2 are respectively provided with fixing grooves 17 for installing and fixing the detachable iron core 5 and the fixed iron core 4. Both ends of the fixed lower shell 2 are provided with a ring of retaining strips 10 on the outer wall. Both ends of the detachable upper shell 3 are provided with a ring of retaining grooves 13 that engage with the retaining strips 10.

[0028] A set of fixed coils 6 are wound on the left and right halves of the fixed iron core 4. The opposite ends of the two sets of fixed coils 6 are respectively connected to two connecting pipes 7 fixed inside the lower part of the fixed lower shell 2. The front of the fixed lower shell 2 is provided with screw terminals 8 that are threaded to the connecting pipes 7. The upper ends of the two sets of fixed coils 6 are respectively fixedly connected to two pipe clamps 9 fixed at both ends of the fixed lower shell 2.

[0029] A set of detachable coils 11 is wound around the surface of the detachable iron core 5. The detachable coils 11 and the two sets of fixed coils 6 are wound in the same spiral direction on the detachable iron core 5 and the fixed iron core 4 respectively. The winding pitch of the fixed coils 6 and the detachable coils 11 is equal. Both ends of the detachable coils 11 are connected to two terminal plugs 12 fixed at both ends of the detachable upper shell 3. The two terminal plugs 12 are respectively inserted into two pipe clamps 9. The pipe clamps 9 are arranged vertically with the opening facing upward and are funnel-shaped with expansion joints on the lower half of the side wall. The pipe clamps 9 and the terminal plugs 12 are inserted with an interference fit.

[0030] Connecting ears 14 are provided on the outer sides of both ends of the fixed lower shell 2 and the detachable upper shell 3. Fastening bolts 15 and fastening nuts 16 are installed between the connecting ears 14 on the fixed lower shell 2 and the detachable upper shell 3. Limit buckles 18 are fixed inside the fixed lower shell 2 and the detachable upper shell 3. The wiring pipe 7, pipe clamp 9 and wiring plug 12 are all fixed by the limit buckles 18.

[0031] Working principle:

[0032] By removing the fastening bolts 15 and nut 16, the fixed lower shell 2 and the detachable upper shell 3 can be separated. This allows for the connection and installation of the fixed lower shell 2 and the detachable upper shell 3 without disconnecting the high-voltage wires of the main coil. The detachable upper shell 3 mates with the fixed lower shell 2, and the wiring plug 12 is inserted into the pipe clamp 9 to complete the physical and electrical connection. The fixed iron core 4 and the detachable iron core 5 are physically joined without obstruction, significantly reducing magnetic leakage and improving magnetic conductivity. The slot 13 and the clip 10 complete the snap-fit ​​sealing. For temporary use, simply install the fastening nut 16 and bolt 15. For long-term use, rotate the fixed lower shell 2 and the detachable upper shell 3, rotating the fixed lower shell 2 upwards so that the slot 13 opens upwards. Seal the slot 13 and the clip 10 with insulating glue, and then rotate the fixed lower shell 2 downwards to secure the entire assembly using the fixing plate 1. This method is convenient to use and significantly improves accuracy.

[0033] It should be noted that, in this document, terms such as “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0034] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-precision current transformer with impedance balance compensation, comprising a fixed plate (1), a cavity semi-circular annular fixed lower shell (2) fixedly connected to the fixed plate (1), a cavity semi-circular detachable upper shell (3) installed above the fixed lower shell (2), and a fixed iron core (4) and a detachable iron core (5) respectively fixedly installed inside the fixed lower shell (2) and the detachable upper shell (3), characterized in that: The fixed lower shell (2) and the detachable upper shell (3) are both open at their opposite ends. The fixed iron core (4) and the detachable iron core (5) are both semi-circular and their opposite ends are close together to form a complete circular structure. The left and right halves of the fixed iron core (4) are each wound with a set of fixed coils (6). The opposite ends of the two sets of fixed coils (6) are respectively connected to two connecting pipes (7) fixed inside the lower part of the fixed shell (2). The front of the fixed shell (2) is provided with screw terminals (8) that are threaded to the connecting pipes (7). The upper ends of the two sets of fixed coils (6) are respectively fixedly connected to two pipe clamps (9) fixed at both ends of the fixed shell (2). A ring of clips (10) is provided on the outer walls of both ends of the fixed shell (2). The surface of the detachable iron core (5) is wound with a set of detachable coils (11). The detachable coils (11) and the two sets of fixed coils (6) are wound in the same spiral direction on the detachable iron core (5) and the fixed iron core (4), respectively. Both ends of the detachable coils (11) are connected to two wire rods (12) fixed at both ends of the detachable upper shell (3). The two wire rods (12) are respectively inserted into two pipe clamps (9). The outer walls of both ends of the detachable upper shell (3) are provided with a groove (13) that engages with the clip (10). Connecting ears (14) are provided on the outer sides of both ends of the fixed lower shell (2) and the detachable upper shell (3). Fastening bolts (15) and fastening nuts (16) are installed between the connecting ears (14) on the fixed lower shell (2) and the detachable upper shell (3).

2. The impedance-balanced compensation high-precision current transformer according to claim 1, characterized in that: The fixed iron core (4) and the detachable iron core (5) are the same in shape and size and are arranged symmetrically at the top and bottom. The interior of the detachable upper shell (3) and the fixed lower shell (2) are respectively provided with fixing grooves (17) for installing and fixing the detachable iron core (5) and the fixed iron core (4).

3. The impedance-balanced compensation high-precision current transformer according to claim 1, characterized in that: The winding pitch of the fixed coil (6) and the detachable coil (11) is the same.

4. The impedance-balanced compensation high-precision current transformer according to claim 1, characterized in that: Both the fixed lower shell (2) and the detachable upper shell (3) are fixed with limit buckles (18), and the wiring pipe (7), pipe clamp (9) and wiring plug (12) are respectively fixed by the limit buckles (18).

5. The impedance-balanced compensation high-precision current transformer according to claim 1, characterized in that: The pipe clamp (9) is flared in shape with its opening facing upward and vertically arranged, and the lower half of its side wall is provided with an expansion joint. The pipe clamp (9) is inserted into the wiring plug (12) with an interference fit.

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