Current transformer with high-voltage end capacitor electricity taking device

Abstract

The utility model discloses a current transformer with a high-voltage end capacitor electricity taking device, and relates to the technical field of current transformers. Comprising a primary winding, a secondary winding and a capacitance electricity taking device, the capacitor electricity taking device comprises a shielding copper foil, a forming copper foil and a capacitor net rack, the shielding copper foil is fixed at the P1 end of the secondary winding, the forming copper foil is fixed at the P2 end of the secondary winding, the capacitor net rack is installed at the position close to the P2 end of the secondary winding, and the capacitor net rack and the forming copper foil are connected together; a C1 terminal is led out from the capacitor net rack, and a C2 terminal is led out from the shielding copper foil. The current in the circuit can be measured, and the capacitance including the capacitance at the high-voltage end and the capacitance at the low-voltage end can be extracted. Measuring the capacitance value L1 between the P1 end or the P2 end and the C1 end, namely the high-voltage end capacitance, and adjusting the value L1 by adjusting the distance between the iron net and the primary winding; and the capacitance value L2 between the C1 end and the C2 end, namely the capacitance of the low-voltage end, can be measured.

Description

Technical Field

[0001] The utility model relates to the technical field of current transformers, in particular to a current transformer with a high-voltage end capacitor power taking device. Background Art

[0002] A current transformer is a device that works on the principle of electromagnetic induction and is used to convert large current on the primary side into small current on the secondary side for measurement, protection and control.

[0003] When the line current, that is, the primary current of the transformer changes, the secondary current of the transformer also changes accordingly, transmitting the information of the line current change to the measuring instruments, meters, relay protection, and automatic control devices. Traditional current transformers are connected in series in the line to measure the line current.

[0004] The latest switch cabinet has a locking function. An electric display device needs to be connected between the current transformer and the switch cabinet. The corresponding current transformer must have a capacitor power supply device to output signals to the electric display device. Therefore, a current transformer with a high-voltage end capacitor power supply device is required. Utility Model Content

[0005] The purpose of the utility model is to provide a current transformer for obtaining capacitance value in a running state, which combines a primary winding, a secondary winding and a capacitance power taking device into one body, realizes capacitance signal extraction, and outputs a signal to an electric display device.

[0006] To achieve the above-mentioned purpose, the present application proposes a current transformer with a high-voltage end capacitor power supply device, comprising a primary winding, a secondary winding and a capacitor power supply device, wherein the secondary winding is sleeved on the primary winding; the capacitor power supply device comprises a shielded copper foil, a shaped copper foil and a capacitor grid, wherein the shielded copper foil is fixed at the P1 end of the secondary winding, the shaped copper foil is fixed at the P2 end of the secondary winding, the capacitor grid is installed at a position close to the P2 end of the secondary winding, and the capacitor grid is connected to the shaped copper foil; a C1 terminal is led out from the capacitor grid, and a C2 terminal is led out from the shielded copper foil.

[0007] Furthermore, the primary winding serves as an electrode of the capacitor, which includes a P1 terminal board, a P1 connecting plate, a conductive rod, a P2 connecting plate, and a P2 terminal board. One end of the conductive rod is connected to the P1 terminal board through the P1 connecting plate, and the other end of the conductive rod is connected to the P2 terminal board through the P2 connecting plate. The P1 terminal board and the P2 terminal board are symmetrically arranged.

[0008] Furthermore, the secondary winding comprises an iron core, an enameled round copper wire and an outer insulating layer, the enameled round copper wire embedded in the outer insulating layer is wound on the iron core; the secondary winding is sleeved on the conductive rod of the primary winding.

[0009] Furthermore, the shaped copper foil is a combination of PMP composite paper, cardboard, and wide copper foil bonded together by double-sided tape, wherein the order from top to bottom is a layer of PMP composite paper, a layer of cardboard, a wide copper foil, a layer of cardboard, and a layer of PMP composite paper, wherein the wide copper foil serves as an electrode of the capacitor, and a first high-temperature wire is welded in the middle of the long side of the wide copper foil, and a first wire nose is welded at the end of the first high-temperature wire.

[0010] Furthermore, the shielding copper foil comprises a narrow copper foil and a second high-temperature wire welded into one body, wherein the narrow copper foil serves as an electrode of the capacitor, and an end of the second high-temperature wire is connected to the C2 terminal.

[0011] Furthermore, the capacitor grid comprises an iron mesh and a thick copper wire welded together, wherein the iron mesh serves as an electrode of the capacitor, and embedded nuts are welded at both ends of the thick copper wire to form the thick copper wire into a "J" shape.

[0012] Furthermore, a thin bare copper wire is wound into a spring shape, wrapped around the edge of the iron mesh, and then the iron mesh is bent into a U shape.

[0013] Furthermore, a short high-temperature wire and a long high-temperature wire are welded to one end of the thick copper wire, a second wire nose is welded to the end of the short high-temperature wire, and the end of the long high-temperature wire is connected to the C1 terminal.

[0014] As a further step, the U-shaped opening of the iron mesh of the capacitor grid is sleeved on the lower part of the P2 end connecting plate, and the capacitor grid is not in contact with the primary winding and the secondary winding, maintaining a certain insulation distance.

[0015] As a further step, a first wire nose on the first high-temperature wire of the formed copper foil and a second wire nose on the short high-temperature wire of the capacitor grid are connected together by bolts.

[0016] Compared with the prior art, the above technical scheme adopted by the utility model has the following advantages: the current transformer with high-voltage end capacitor power extraction device of the present application can not only measure the current in the circuit, but also extract capacitance, including the capacitance at the high-voltage end and the capacitance at the low-voltage end. The capacitance value between the P1 end or the P2 end and the C1 end is measured as L1, that is, the capacitance at the high-voltage end, and the L1 value is adjusted by adjusting the distance between the iron mesh and the primary winding; the capacitance value between the C1 end and the C2 end can also be measured as L2, that is, the capacitance at the low-voltage end. In the present device, there is sufficient insulation distance between the primary winding and the secondary winding, the capacitor grid and the primary winding, and the capacitor grid and the secondary winding, which neither affects the accuracy of the current transformer nor outputs signals to the electric display device; it neither affects the insulation of the current transformer nor the local discharge requirements of the product. The current transformer with high-voltage end capacitor power extraction device of the present application is easy to manufacture, and the capacitance value can be accurately controlled by adjusting the distance between the electrodes. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1It is a schematic diagram of the overall structure of a current transformer with a high-voltage end capacitor power supply device;

[0018] Figure 2 It is a schematic diagram of the primary winding structure;

[0019] Figure 3 It is a schematic diagram of the shielding copper foil structure;

[0020] Figure 4 It is a schematic diagram of the structure of formed copper foil;

[0021] Figure 5 is a schematic diagram of the capacitor grid structure;

[0022] Among them: 1. primary winding, 2. secondary winding, 3. shielded copper foil, 4. formed copper foil, 5. capacitor grid, 6. bolt, 7. S1 terminal, 8. S2 terminal, 9. C1 terminal, 10. C2 terminal, 11. P1 terminal block, 12. P2 terminal block, 13. P1 connecting plate, 14. conductive rod, 15. P2 connecting plate, 16. high temperature resistant layer, 17. buffer layer, 18. enameled round copper wire, 19. outer insulation layer, 20. first high temperature wire, 21. first wire nose, 22. PMP composite paper, 23. cardboard, 24. wide copper foil, 25. narrow copper foil, 26. second high temperature wire, 27. iron mesh, 28. thick copper wire, 29. thin bare copper wire, 30. embedded nut, 31. short high temperature wire, 32. long high temperature wire, 33. second wire nose, 34. iron core. DETAILED DESCRIPTION

[0023] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0024] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0025] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" means two or more, unless otherwise clearly and specifically defined. "Several" means one or more, unless otherwise clearly and specifically defined.

[0026] In the description of the present application, it should be understood that the terms "center", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0027] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0028] like Figure 1 As shown, this embodiment provides a current transformer with a high-voltage end capacitor power supply device, including a primary winding 1, a secondary winding 2 and a capacitor power supply device, the secondary winding 2 is sleeved on the primary winding 1; the capacitor power supply device includes a shielding copper foil 3, a shaped copper foil 4, and a capacitor grid 5, the shielding copper foil 3 is fixed at the P1 end of the secondary winding 2, and the shaped copper foil 4 is fixed at the P2 end of the secondary winding 2; the capacitor grid 5 is installed at a position close to the P2 end of the secondary winding and is connected to the shaped copper foil 4; the capacitor grid 5 does not contact the primary winding 1 and the secondary winding 2, and maintains a certain distance.

[0029] like Figure 2 As shown, the primary winding 1 serves as an electrode of the capacitor, and includes a P1 terminal board 11, a P1 connecting board 13, a conductive rod 14, a P2 connecting board 15, a P2 terminal board 12, and a high temperature resistant layer 16 and a buffer layer 17 wrapped around the outside of the primary winding; the primary winding 1 is made of copper.

[0030] In this embodiment, the secondary winding 2 includes an iron core 34, an enameled round copper wire 18 and an outer insulating layer 19, and the enameled round copper wire built into the outer insulating layer is wound on the iron core; the secondary winding 2 is sleeved on the conductive rod 14 of the primary winding 1. The distance between the primary winding 1 and the secondary winding 2 meets the insulation requirements of withstand voltage. The current inflow end of the primary winding 1 is P1, and the current outflow end is P2. The current outflow end of the secondary winding 2 is S1, and the current inflow end is S2. P1 and S1 are the same-name terminals and have a negative polarity.

[0031] like Figure 3As shown, the shielding copper foil 3 includes a narrow copper foil 25 and a second high-temperature wire which are welded into one body, wherein the narrow copper foil serves as an electrode of the capacitor, and the end of the second high-temperature wire is connected to the C2 terminal 10 .

[0032] like Figure 4 As shown, the formed copper foil 4 is a combination of PMP composite paper 22, paperboard 23, and wide copper foil 24 bonded by double-sided adhesive, and the order from top to bottom is a layer of PMP composite paper 22, a layer of paperboard 23, wide copper foil 24, a layer of paperboard 23, and a layer of PMP composite paper 22. The first high-temperature wire is welded in the middle of the long side of the wide copper foil 24, and the first wire nose 21 is welded at the end of the first high-temperature wire 20. The wide copper foil 24 serves as an electrode of the capacitor, the PMP composite paper 22 plays an insulating role, and the paperboard 23 plays an insulating and fixing role. The paperboard 23 is clamped on both sides of the wide copper foil 24 to protect the wide copper foil from deformation. The PMP composite paper 22 and the paperboard 23 ensure that the entire formed copper foil has sufficient insulation.

[0033] In this embodiment, the shielding copper foil 3 is fixed to the P1 end of the secondary winding 2, and the shaped copper foil 4 is fixed to the P2 end of the secondary winding 2. This layout makes full use of the existing space and facilitates the wiring connection between the shaped copper foil 4 and the capacitor grid 5. The outer insulating layer 19 of the secondary winding 2 ensures that there is sufficient insulation between the shielding copper foil 3 and the shaped copper foil 4 and the enameled round copper wire 18, and does not cause low insulation resistance and withstand voltage breakdown.

[0034] like Figure 5 As shown, the capacitor grid 5 includes an iron mesh 27 and a thick copper wire 28 welded into one. First, a thin bare copper wire 29 is wound into a spring shape and wound around the edge of the iron mesh 27, and then the iron mesh 27 is bent into a U shape. The iron mesh 27 serves as an electrode of the capacitor. The thin bare copper wire 29 is wound around the edge of the iron mesh 27 to ensure that the iron mesh 27 has no sharp edges and the electric field is uniform. Embedded nuts 30 are welded at both ends of the thick copper wire 28, and the thick copper wire 28 is made into a "F" shape. The thick copper wire 28 is welded under the iron mesh 27 to play a supporting role. A short high-temperature wire 31 and a long high-temperature wire 32 are welded at one end of the thick copper wire 28, and a second wire nose 33 is welded at the end of the short high-temperature wire 31, and the end of the long high-temperature wire 32 is connected to the C1 terminal 9.

[0035] In this embodiment, the capacitor grid 5 is installed near the P2 end of the secondary winding 2, the U-shaped mouth of the iron net 27 is sleeved at the lower part of the P2 connecting plate 15, and the outer edge of the iron net 27 does not exceed the extension line of the P2 connecting plate 15. The iron net 27 does not contact the primary winding 1 and the secondary winding 2, and maintains a certain insulation distance. The capacitor grid 5 is installed near the P2 end of the secondary winding 2 to avoid the secondary outlet of the P1 end of the secondary winding 2, and is convenient for connection with the formed copper foil 4, while also making full use of the space area.

[0036] In this embodiment, the first wire nose 21 on the first high-temperature wire 20 of the shaped copper foil 4 and the second wire nose 33 on the short high-temperature wire 31 of the capacitor grid 5 are bolted together, and the wide copper foil 24 serving as an electrode of the capacitor is connected to the C1 terminal 9 as a whole, that is, the shaped copper foil 4 and the capacitor grid 5 share one C1 terminal 9.

[0037] Specifically, the primary winding 1 is used as an electrode of the capacitor, the iron mesh 27 is used as an electrode of the capacitor, and a current is passed between the primary winding 1 and the capacitor grid 5, that is, a current is passed between the P1 terminal board 11 or the P2 terminal board 12 and the C1 terminal 9 to generate a capacitor, which is L1, i.e., a high-voltage end capacitor. The narrow copper foil 25 is used as an electrode of the capacitor, and the wide copper foil 24 is used as an electrode of the capacitor. A current is passed between the narrow copper foil 25 and the wide copper foil 24, that is, a current is passed between the C1 terminal 9 and the C2 terminal 10 to generate a capacitor, which is L2, i.e., a low-voltage end capacitor.

[0038] The high-voltage end capacitor L1 provides a signal for the electric display device, and the value of L1 is adjusted by adjusting the distance between the iron mesh 27 and the primary winding 1. The low-voltage end capacitor L2 only provides a value to verify the consistency of the structural dimensions of this batch of products. Although the two sets of capacitors share the C1 terminal 9 when measuring, because the electrodes are independent, the value of the low-voltage end capacitor L2 will not affect the value of the high-voltage end capacitor L1.

[0039] The current transformer with a high-voltage end capacitance power extraction device of the present application can both measure the current in the line and extract capacitance, including the capacitance at the high-voltage end and the capacitance at the low-voltage end.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A current transformer with a high-voltage end capacitor power supply device, characterized in that: It includes a primary winding, a secondary winding and a capacitor power supply device, wherein the secondary winding is sleeved on the primary winding; the capacitor power supply device includes a shielding copper foil, a shaped copper foil and a capacitor grid, wherein the shielding copper foil is fixed at the P1 end of the secondary winding, the shaped copper foil is fixed at the P2 end of the secondary winding, the capacitor grid is installed at a position close to the P2 end of the secondary winding, and the capacitor grid is connected to the shaped copper foil; a C1 terminal is led out from the capacitor grid, and a C2 terminal is led out from the shielding copper foil.

2. A current transformer with a high-voltage end capacitor power supply device according to claim 1, characterized in that: The primary winding serves as an electrode of the capacitor, and includes a P1 terminal board, a P1 connecting plate, a conductive rod, a P2 connecting plate, and a P2 terminal board. One end of the conductive rod is connected to the P1 terminal board through the P1 connecting plate, and the other end of the conductive rod is connected to the P2 terminal board through the P2 connecting plate. The P1 terminal board and the P2 terminal board are symmetrically arranged.

3. A current transformer with a high-voltage end capacitor power supply device according to claim 2, characterized in that: The secondary winding comprises an iron core, an enameled round copper wire and an outer insulating layer, wherein the enameled round copper wire built in the outer insulating layer is wound on the iron core; the secondary winding is sleeved on the conductive rod of the primary winding.

4. A current transformer with a high-voltage end capacitor power supply device according to claim 1, characterized in that: The shaped copper foil is a combination of PMP composite paper, cardboard, and wide copper foil bonded together by double-sided tape, wherein the order from top to bottom is a layer of PMP composite paper, a layer of cardboard, a wide copper foil, a layer of cardboard, and a layer of PMP composite paper, wherein the wide copper foil serves as an electrode of the capacitor, and a first high-temperature wire is welded in the middle of the long side of the wide copper foil, and a first wire nose is welded at the end of the first high-temperature wire.

5. A current transformer with a high-voltage end capacitor power supply device according to claim 1, characterized in that: The shielding copper foil comprises a narrow copper foil and a second high-temperature wire which are welded into one body, wherein the narrow copper foil serves as an electrode of the capacitor, and the end of the second high-temperature wire is connected to the C2 terminal.

6. A current transformer with a high-voltage end capacitor power supply device according to claim 2 or 4, characterized in that: The capacitor grid frame comprises an iron mesh and a thick copper wire welded together, wherein the iron mesh serves as an electrode of the capacitor, embedded nuts are welded at both ends of the thick copper wire, and the thick copper wire is made into a "J" shape.

7. A current transformer with a high-voltage end capacitor power supply device according to claim 6, characterized in that: Wrap the thin bare copper wire into a spring shape, wrap it around the edge of the iron mesh, and then bend the iron mesh into a U shape.

8. A current transformer with a high-voltage end capacitor power supply device according to claim 6, characterized in that: A short high-temperature wire and a long high-temperature wire are welded to one end of the thick copper wire, a second wire nose is welded to the end of the short high-temperature wire, and the end of the long high-temperature wire is connected to the C1 terminal.

9. A current transformer with a high-voltage end capacitor power supply device according to claim 7, characterized in that: The U-shaped opening of the iron mesh of the capacitor grid is sleeved on the lower part of the P2 end connecting plate, and the capacitor grid is not in contact with the primary winding and the secondary winding, maintaining a certain insulation distance.

10. A current transformer with a high-voltage end capacitor power supply device according to claim 8, characterized in that: The first wire nose on the first high-temperature wire of the formed copper foil and the second wire nose on the short high-temperature wire of the capacitor grid are connected together with bolts.

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