CN212622772U - Current transformer for monitoring current of neutral point of transformer and complete equipment - Google Patents

Abstract

The utility model discloses a current transformer and complete equipment for transformer neutral point current monitoring, current transformer includes staple bolt and mutual-inductor body, the staple bolt is established and is installed on the mutual-inductor body, the mutual-inductor body assembles the ring structure that forms for the assembly module, and inlay in each assembly module and be equipped with the iron core, make the iron core end to end contact connection of each assembly module form annular iron core structure after assembling to form ring structure, and one of them assembly module is the detection module who encapsulates the detection coil, and the detection coil in this detection module is around establishing on the iron core in this detection module; the transformer neutral point current monitoring complete device comprises a central processing module, an alternating current sampling module, a communication alarm module and the transformer neutral point current monitoring current transformer. The utility model discloses can conveniently realize monitoring the neutral point electric current of main transformer when normal operating, have the installation moreover and dismantle convenient, fixed swift reliable advantage.

Description

Current transformer for monitoring current of neutral point of transformer and complete equipment

Technical Field

The utility model relates to a transformer neutral point current monitoring facilities's improvement, concretely relates to current transformer and integrated equipment for transformer neutral point current monitoring.

Background

The heating and burning events of the neutral point grounding device of the main transformer often occur in the power grid. After the neutral point of the main transformer loses grounding, the line differential protection, the distance protection and the zero sequence protection are refused to operate, but the non-grounding phase voltage is increased to be line voltage, because the insulation cost of the line and the equipment is designed according to the phase voltage, the insulation of a power system is seriously threatened, the voltage of the neutral point of the main transformer losing grounding generates displacement, the neutral point bears overvoltage impact, the insulation level of the neutral point of the main transformer is lower, and the safe and stable operation of the main equipment is seriously threatened. The current transformer is additionally arranged on a neutral point of a main transformer of a transformer substation and used for taking neutral point current, the neutral point current is very small (only about 1A) when the main transformer normally operates, the current is difficult to monitor by a common current transformer, and the problems of troublesome installation and disassembly and difficult fixation exist due to the higher position of the neutral point.

SUMMERY OF THE UTILITY MODEL

The utility model discloses the technical problem who solves: to the above-mentioned problem of prior art, a current transformer and integrated equipment are used in transformer neutral point current monitoring is provided, the utility model discloses can conveniently realize monitoring the neutral point current of main transformer when normal operation, have moreover that the installation is dismantled conveniently, fixed swift reliable advantage.

In order to solve the technical problem, the utility model discloses a technical scheme be:

the utility model provides a current transformer for monitoring current of transformer neutral point, includes staple bolt and mutual-inductor body, the staple bolt is established the cover and is established and install on the mutual-inductor body, the circular ring shaped structure that the formation was assembled to the module is assembled for at least two to the mutual-inductor body, and each inlays in assembling the module and be equipped with the iron core for assemble the iron core end to end contact connection that forms annular iron core structure of forming each assembly module behind the circular ring shaped structure, and one of them assembles the module and for the detection module who is packaged with the detection coil, and the detection coil among this detection module is around establishing on the iron core in this detection module.

Optionally, the assembly module is an integrated sealing structure made of resin in a wrapping mode.

Optionally, a cable connector is further disposed on the detection module, and the cable connector is electrically connected to the connection terminal of the detection coil.

Optionally, an outer positioning sliding groove arranged along the axial direction of the mutual inductor body is formed in the outer wall of the assembling module, a positioning bolt is arranged on the hoop, and the positioning bolt is inserted and fixed in the outer positioning sliding groove.

Optionally, still be equipped with interior location spout on the inner wall of assembling the module, insert in the interior location spout and be equipped with the location slider, be equipped with rings on the location slider.

Furthermore, the utility model provides a transformer neutral point current monitoring integrated equipment, including central processing module, exchange sampling module, communication alarm module and aforementioned transformer neutral point current monitoring current transformer, transformer neutral point current monitoring is continuous with the input of exchanging sampling module with current transformer, it links to each other with central processing module to exchange sampling module's output, central processing module links to each other with communication alarm module.

Optionally, the central processing module is further connected with a signal input module.

Compared with the prior art, the utility model discloses a current transformer for monitoring transformer neutral point current has following advantage:

1. the utility model discloses a mutual-inductor body assembles the ring annular structure that the module assembled the formation for at least two, and each assembles and inlays in the module and be equipped with the iron core, make and assemble the iron core end to end contact connection that forms the module behind the ring annular structure and form annular iron core structure, the closed structure of iron core has been realized through the above-mentioned mode, thereby can strengthen the detection performance to the main transformer small current about only 1A when normal operating, can conveniently realize monitoring the neutral point current of main transformer when normal operating.

2. The utility model discloses a staple bolt and mutual-inductor body, the staple bolt is established the cover and is established and install on the mutual-inductor body, the ring annular structure that the formation was assembled to the module is assembled for at least two to the mutual-inductor body, can realize the equipment and the dismantlement of staple bolt and mutual-inductor body when convenient through above-mentioned structure, has the installation and dismantles convenient, fixed swift reliable advantage.

Drawings

Fig. 1 is a schematic structural view of a current transformer according to an embodiment of the present invention.

Fig. 2 is the embodiment of the utility model provides an exploded structure schematic diagram of mutual-inductor body.

Fig. 3 is a schematic structural diagram of a monitoring kit according to an embodiment of the present invention.

Illustration of the drawings: 1. hooping; 11. positioning a bolt; 2. a transformer body; 21. assembling modules; 211. an outer positioning chute; 212. an inner positioning chute; 213. positioning the sliding block; 214. a hoisting ring; 22. an iron core; 23. a detection coil; 24. a cable connector; 3. a central processing module; 4. an alternating current sampling module; 5. a communication alarm module; 6. and a signal input module.

Detailed Description

As shown in fig. 1 and fig. 2, the current transformer for monitoring the current of the neutral point of the transformer in the embodiment includes a hoop 1 and a transformer body 2, the hoop 1 is sleeved on the transformer body 2, the transformer body 2 is an annular structure formed by assembling at least two assembling modules 21, and an iron core 22 is embedded in each assembling module 21, so that the iron cores 22 assembled into the modules after being assembled into the annular structure are in contact connection end to form an annular iron core structure, one of the assembling modules 21 is a detection module packaged with a detection coil 23, and the detection coil 23 in the detection module is wound on the iron core 22 in the detection module. In the embodiment, the iron core 22 is embedded in each assembly module 21, so that the iron cores 22 of the assembly modules are connected in an end-to-end contact manner to form an annular iron core structure after being assembled to form an annular structure, thereby realizing a closed structure of the iron core, enhancing the detection performance of the main transformer with only about 1A of small current during normal operation, and conveniently realizing the monitoring of the neutral point current of the main transformer during normal operation; and can also realize the equipment and the dismantlement of staple bolt and mutual-inductor body when convenient, have the installation and dismantle convenient, fixed swift reliable advantage.

In order to improve the reliability of the assembly module 21, in this embodiment, the assembly module 21 is an integrated sealing structure made of resin, and has the advantages of firm and reliable structure and good waterproof performance.

In order to facilitate the connection of the detection coil 23, as shown in fig. 1 and 2, the detection module of the present embodiment is further provided with a cable connector 24, and the cable connector 24 is electrically connected to the connection terminal of the detection coil 23.

In order to prevent relative motion between the hoop 1 and the transformer body 2 when the hoop 1 is sleeved on the transformer body 2, as shown in fig. 1 and fig. 2, an outer positioning chute 211 arranged along the axial direction of the transformer body 2 is arranged on the outer wall of the splicing module 21 in the embodiment, a positioning bolt 11 is arranged on the hoop 1, and the positioning bolt 11 is inserted and fixed in the outer positioning chute 211. The setting of location bolt 11 is in the one end of staple bolt 1, inserts it and can make each assemble module 21 and all be connected fixedly with staple bolt 1 in the outer positioning chute 211 to can prevent to take place relative motion between staple bolt 1, the mutual-inductor body 2 when staple bolt 1 cover is established and is installed on mutual-inductor body 2, make fastening this moment or dismantle staple bolt 1 can be more convenient.

In order to prevent the current transformer from moving relative to the fixed neutral point cable after being installed, as shown in fig. 1 and fig. 2, an inner positioning sliding groove 212 is further disposed on the inner wall of the assembling module 21 in this embodiment, a positioning sliding block 213 is inserted into the inner positioning sliding groove 212, and a hanging ring 214 is disposed on the positioning sliding block 213. The current transformer and the fixed neutral point cable can be conveniently bound and fixed through the hanging ring 214, the detection accuracy of the current transformer can be improved, and the current transformer can be prevented from falling.

As shown in fig. 3, the transformer neutral point current monitoring complete equipment of this embodiment includes a central processing module 3, an ac sampling module 4, a communication alarm module 5, and the aforementioned current transformer for transformer neutral point current monitoring (see a in fig. 3) of this embodiment, the current transformer for transformer neutral point current monitoring is connected to an input end of the ac sampling module 4, an output end of the ac sampling module 4 is connected to the central processing module 3, and the central processing module 3 is connected to the communication alarm module 5. In this embodiment, the neutral point current signal collected by the current transformer for monitoring the neutral point current of the transformer is output to the central processing module 3 through the output end of the ac sampling module 4, and the central processing module 3 may also alarm through the communication alarm module 5 according to a set condition, for example, send an alarm signal when the current exceeds the limit. As shown in fig. 3, in this embodiment, the central processing module 3 is further connected to a signal switching-in module 6, so as to receive a switching-in signal to perform transformer neutral point current monitoring, and facilitate flexible interaction with a substation control system. In fig. 3, b is a neutral point disconnector, c is a lightning arrester, and d is a discharge gap.

Through practical tests, the current transformer for monitoring the current of the neutral point of the transformer has the characteristics of high precision, small transformation ratio, open type, easiness in saturation and the like. High precision: through test data analysis, the precision is higher than 0.2S; small transformation ratio: the transformation ratio of the case current transformer is 10/1 and 5/1, and 1 ampere primary current can be correctly fed back to secondary equipment; open type: as shown in fig. 1 and 2, the current transformer developed according to the specification and position characteristics of the transformer neutral point grounding flat iron is formed by overlapping two pieces, can be directly buckled on the grounding flat iron without power failure during installation, then is fastened, is sealed by composite insulating grease, and is waterproof, moistureproof and high temperature resistant. Very easy saturation: when an electric power system has ground fault, a large primary current can appear, and because the transformation ratio of the newly developed current transformer is small, hundreds of even thousands of amperes of current can appear when the current transformer is fed back to the secondary, and the complete equipment is burnt out, the current transformer is extremely easy to saturate. Through analysis of volt-ampere characteristic data of the current transformer, when the experimental voltage is 40 volts and the current of 42 amperes passes twice, the current transformer of the embodiment is saturated, and the secondary current cannot rise continuously, so that subsequent processing equipment is well protected.

It is above only the utility model discloses a preferred embodiment, the utility model discloses a scope of protection does not only confine above-mentioned embodiment, the all belongs to the utility model discloses a technical scheme under the thinking all belongs to the utility model discloses a scope of protection. It should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims (7)

1. The utility model provides a current transformer for transformer neutral point current monitoring which characterized in that: including staple bolt (1) and transformer body (2), staple bolt (1) cover is established and is installed on transformer body (2), the ring shape structure of formation is assembled for at least two modules (21) in transformer body (2), and each assembles and inlays in module (21) and be equipped with iron core (22) for each is assembled and is equipped with iron core (22) end to end contact connection of each iron core (22) of assembling the module behind the ring shape structure and forms annular iron core structure, and one of them assembles module (21) and is packaged with the detection module of detecting coil (23), and detection coil (23) in this detection module around establishing on iron core (22) in this detection module.

2. The current transformer for monitoring the current of the neutral point of the transformer according to claim 1, wherein: the assembly module (21) is an integrated sealing structure made of resin in a wrapping mode.

3. The current transformer for monitoring the current of the neutral point of the transformer according to claim 2, wherein: the detection module is also provided with a cable connector (24), and the cable connector (24) is electrically connected with the connecting terminal of the detection coil (23).

4. The current transformer for monitoring the current of the neutral point of the transformer according to claim 2, wherein: the outer wall of the assembly module (21) is provided with an outer positioning sliding groove (211) which is arranged along the axial direction of the mutual inductor body (2), the hoop (1) is provided with a positioning bolt (11), and the positioning bolt (11) is inserted and fixed in the outer positioning sliding groove (211).

5. The current transformer for monitoring the current of the neutral point of the transformer according to claim 1, wherein: the inner wall of the assembly module (21) is further provided with an inner positioning sliding groove (212), a positioning sliding block (213) is inserted into the inner positioning sliding groove (212), and the positioning sliding block (213) is provided with a hanging ring (214).

6. A transformer neutral point current monitoring complete equipment is characterized by comprising a central processing module (3), an alternating current sampling module (4), a communication alarm module (5) and the transformer neutral point current monitoring current transformer according to any one of claims 1 to 5, wherein the transformer neutral point current monitoring current transformer is connected with the input end of the alternating current sampling module (4), the output end of the alternating current sampling module (4) is connected with the central processing module (3), and the central processing module (3) is connected with the communication alarm module (5).

7. Transformer neutral point current monitoring kit according to claim 6, characterized in that the central processing module (3) is further connected with a signal switching-in module (6).

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