CN215575334U - Transformer core grounding current measuring structure and device - Google Patents
Transformer core grounding current measuring structure and device Download PDFInfo
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- CN215575334U CN215575334U CN202121483389.1U CN202121483389U CN215575334U CN 215575334 U CN215575334 U CN 215575334U CN 202121483389 U CN202121483389 U CN 202121483389U CN 215575334 U CN215575334 U CN 215575334U
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Abstract
The utility model provides a transformer core grounding current measuring structure and a device, which relate to the technical field of transformer grounding current measurement and solve the technical problem of inconvenient measurement of the transformer core grounding current in the prior art, wherein the transformer core grounding current measuring structure comprises a normally closed grounding circuit, a normally-open measuring circuit provided with a current measuring device and switching devices arranged on the normally closed grounding circuit and the normally-open measuring circuit, two ends of the normally-closed grounding circuit are respectively connected with an iron core leading-out and grounding, and two ends of the normally-open measuring circuit are connected and arranged on the normally-closed grounding circuit; the measuring device comprises a protective device and a transformer iron core grounding current measuring structure; the utility model only needs to reform the original transformer iron core grounding flat iron in advance, does not need to carry equipment additionally during measurement, does not need a power-off transformer, has simple structure, is convenient for reformation, can carry out current measurement operation on the premise of not influencing the normal operation of the transformer, and is convenient and fast to operate.
Description
Technical Field
The utility model relates to the technical field of transformer grounding current measurement, in particular to a transformer iron core grounding current measurement structure and a device.
Background
In the normal operation of the transformer, a charged coil and a lead wire can generate an uneven electric field, metal components such as an iron core, a clamping piece and the like can induce different electric potentials due to different positions, when the potential difference between two points reaches the value capable of breaking down insulation between the two points, intermittent spark discharge can be generated, the oil decomposition and solid insulation damage of the transformer can be accelerated due to the intermittent discharge, accidents can be caused for a long time, in order to avoid the situations, the iron core and other metal parts are required to be connected with an oil tank and grounded together, so that the iron core and other metal parts are in zero potential, the iron core is required to be grounded at one point reliably, the iron core of the transformer is an important link of electric-magnetic-electric conversion, and the measurement of the grounding current of the iron core is an important means for monitoring the faults of the iron core of the transformer.
In order to prevent the transformer damage caused by the multipoint earthing of the iron core, the current measurement is carried out on the earthing of the iron core of the transformer, and the current measurement is carried out according to the regulation of DLT573-2010 'inspection guide of power transformer' 6.4: when the grounding current of the iron core is measured during the operation of the transformer, a resistance current-limiting measure is additionally arranged when the grounding current is controlled to be below 100mA and is more than 300mA, and power failure treatment is arranged. According to twenty-five key requirements of the national energy agency for prevention of accidents in power production (twelve major requirements for prevention of accidents of large transformers and transformers)' (2014) 12.2.18, an iron core and a clamping piece are led out of a grounded transformer through a small sleeve, a grounding lead is led to a proper position so as to monitor whether circulating current exists in a grounding wire during operation, when the circulating current abnormally changes during operation, the reason should be found out as soon as possible, measures should be taken to deal with the circulating current in time when the circulating current is serious, and the current is generally controlled to be below 100 mA.
At present, each wind power plant is not developed by effective measures, a traditional iron core grounding structure is still adopted, a traditional grounding current measuring method is still adopted when the grounding current is measured, auxiliary measurement is carried out through additionally carried current measuring equipment (a clip-on ammeter), the use and the operation are inconvenient, the traditional measuring method generally reflects that the clip-on ammeter has a large range, the measuring result cannot be displayed, and the accuracy is relatively low.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a transformer core grounding current measuring structure and a device, which aim to solve the technical problem of inconvenient measurement of the transformer core grounding current in the prior art; the utility model has the advantages that the preferred technical scheme in the technical schemes can produce a plurality of technical effects (the switch device is a duplex knife switch, the normally-closed grounding circuit can be simultaneously disconnected and the normally-open measuring circuit can be simultaneously closed through action, the circuit structure is simpler and the operation is more convenient on the premise of ensuring the accurate current measurement, the duplex knife switch comprises a self-return mechanism, the duplex knife switch can automatically return to the initial position after the current measurement is finished, the normally-closed grounding circuit is closed, the normally-open measuring circuit is disconnected, the operation is convenient, the damage of equipment or potential safety hazards and the like caused by forgetting to close the switch after a worker measures the grounding current of an iron core can be effectively avoided, the current measuring device is a magnetoelectric ammeter, the sensitivity and the accuracy are high, the magnetoelectric ammeter is provided with a dial and a transparent window for facilitating data reading, the ammeter selects a milliammeter, the measuring range is milliampere level, so that the data reading is more accurate; the transformer core grounding current measuring device comprises a protective device, can shield rain, snow and the like and is used for protecting a circuit, the protective device is arranged as a shell, an installation cavity is arranged in the shell and is used for installing a measuring structure to form an enclosed protective device, and the protective effect is obvious; the shell is provided with a first connecting end and a second connecting end which are respectively used for connecting the transformer iron core grounding lead-out and the transformer iron core grounding; the first connecting end and the second connecting end are detachably connected by adopting a threaded fastener, so that the original transformer core grounding structure is conveniently reconstructed, and the device is convenient to disassemble and assemble; see below for details.
In order to achieve the purpose, the utility model provides the following technical scheme:
the utility model provides a transformer core grounding current measuring structure, which comprises a normally closed grounding circuit, a normally open measuring circuit and a switching device, wherein: one end of the normally closed grounding circuit is connected with the transformer iron core in a grounding leading-out manner, and the other end of the normally closed grounding circuit is grounded; the two ends of the normally-closed measuring circuit are connected and arranged on the normally-closed grounding circuit, and a current measuring device is arranged on the normally-closed measuring circuit and used for measuring grounding current; the switch device is arranged on the normally closed grounding circuit and the normally open measuring circuit to control the normally closed grounding circuit and the normally open measuring circuit to be opened or closed.
Preferably, the switching device comprises a duplex disconnecting link, and the duplex disconnecting link can simultaneously control the normally closed grounding line to be disconnected and the normally open measuring line to be closed.
Preferably, the double-link disconnecting link is provided with a self-return mechanism so that the normally closed grounding circuit can be automatically closed.
Preferably, the current measuring device is provided as a magnetoelectric ammeter.
Preferably, the magnetoelectric ammeter is provided with a dial for displaying the measured current information; and a transparent window for reading the information of the measured current is arranged on the magnetoelectric ammeter corresponding to the position of the dial.
Preferably, the magnetoelectric ammeter is set as a milliammeter.
The transformer core grounding current measuring device clearly provided by the utility model comprises a protection device, wherein the protection device is internally provided with the transformer core grounding current measuring structure.
Preferably, the protection device comprises a shell, an installation cavity is arranged inside the shell, and the transformer core grounding current measurement structure is arranged in the installation cavity.
Preferably, the shell is provided with a first connecting end and a second connecting end which are respectively electrically connected with two ends of the normally closed grounding circuit, the first connecting end is used for connecting the transformer core to be grounded and led out, and the second connecting end is used for connecting the transformer core to be grounded.
Preferably, the first connecting end is detachably connected with the grounding leading-out end of the transformer iron core through a first threaded fastener; the second connecting end and the transformer core are detachably connected through a second threaded fastener.
The structure and the device for measuring the grounding current of the transformer iron core provided by the utility model at least have the following beneficial effects:
the transformer iron core grounding current measuring structure comprises a normally closed grounding circuit, a normally open measuring circuit and a switch device, wherein one end of the normally closed grounding circuit is connected with the transformer iron core in a grounding mode, the other end of the normally open grounding circuit is grounded, two ends of the normally open measuring circuit are connected and arranged on the normally closed grounding circuit, a current measuring device is arranged on the normally open measuring circuit, the normally closed grounding circuit is closed in a normal state, the transformer iron core is grounded, the normally open measuring circuit is disconnected, and the current measuring device is free of electricity;
the normally closed grounding circuit and the normally open measuring circuit are arranged, when current needs to be measured, a worker controls the normally closed grounding circuit to be disconnected through the switch device, the normally open measuring circuit is closed, at the moment, the current measuring device is electrified, the grounding current can be measured, the whole structure is simple, the installation is convenient, the current measuring operation is convenient, and the measuring result is accurate.
The transformer core grounding current measuring device comprises a protective device, wherein the transformer core grounding current measuring structure is arranged in the protective device, the protective device can protect rain, snow and the like in the daily environment, the internal structure and equipment of the protective device are effectively protected, and the service life of the device is long.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic structural diagram of a transformer core grounding current measurement structure of the present invention;
FIG. 2 is a schematic structural view of example 1 of the present invention;
FIG. 3 is a schematic structural view of example 2 of the present invention;
fig. 4 is a schematic structural diagram of the transformer core grounding current measuring device of the utility model.
Reference numerals
1. A normally closed ground line; 2. a normally-off measurement line; 3. a switching device; 31. a duplex disconnecting link; 311. a disconnecting link operating handle; 32. a self-return mechanism; 33. measuring a line switch; 34. a ground line switch; 4. a current measuring device; 41. a magnetoelectric ammeter; 411. a dial scale; 412. a transparent window; 5. a transformer; 51. leading out the transformer iron core in a grounding way; 52. the transformer iron core is grounded; 6. a guard; 61. a first connection end; 62. a second connection end; 7. a first threaded fastener; 8. a second threaded fastener.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the utility model, and not restrictive of the full scope of the utility model. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.
In the description of the present invention, it is to be understood that the terms "upper", "lower", "outer", "inner", and the like, indicate orientations or positional relationships, are used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referenced components or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.
In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "disposed," "connected," and the like are to be construed broadly, such as "connected," which may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Example 1:
the utility model provides a transformer core grounding current measuring structure, as shown in figure 1, the transformer core grounding current measuring structure comprises a normally closed grounding circuit 1, a normally open measuring circuit 2 and a switch device 3, wherein the wire diameter of the normally closed grounding circuit 1 is not less than 25mm2。
One end of the normally closed grounding circuit 1 is connected with a transformer iron core grounding lead-out 51, and the other end is grounded; two ends of the normally-open measuring line 2 are connected and arranged on the normally-closed grounding line 1, and the normally-open measuring line 2 is provided with a current measuring device 4 for measuring grounding current; the switching device 3 is arranged on the normally closed grounding line 1 and the normally open measuring line 2 to control the normally closed grounding line 1 and the normally open measuring line 2 to be opened or closed.
In a normal state, the normally closed grounding line 1 is in a closed state, the iron core of the transformer 5 is grounded, the normally open measuring line 2 is in an open state, and the current measuring device 4 is in an electroless state.
When the grounding current needs to be measured, the normally closed grounding circuit 1 is disconnected through the switch device 3, the normally open measuring circuit 2 is closed through the switch device 3, the current measuring device 4 is powered on to obtain the grounding current, after the current measurement is completed, the normally closed grounding circuit 1 is restored to a closed state through the switch device 3, and the normally open measuring circuit 2 is restored to an open state.
When the grounding current is measured, equipment such as an ammeter and the like does not need to be carried additionally, the transformer 5 does not need to be powered off, and only the iron core grounding flat iron of the original transformer 5 needs to be modified in advance, so that the grounding current measuring device has the advantages of simple integral structure, small modification project, short period, convenience in installation, capability of carrying out subsequent current measurement on the premise of not influencing the normal operation of the transformer 5, and convenience in operation.
Example 2
As shown in fig. 2, the switching device 3 includes a duplex disconnecting link 31, the duplex disconnecting link 31 adopts a duplex disconnecting link fracture structure to ensure reliable grounding of the original iron core grounding loop, the duplex disconnecting link 31 is substantially a bidirectional switch, and includes a disconnecting link end and two switching-on ends, the two switching-on ends are respectively arranged on the normally closed grounding line 1 and the normally open measuring line 2, and the normally open measuring line 2 can be controlled to be closed while the normally closed grounding line 1 is controlled to be open; by adopting the structure, the equipment damage and the potential safety hazard caused by simultaneous closing or simultaneous opening of the normally closed grounding circuit 1 and the normally open measuring circuit 2 due to misoperation can be effectively avoided.
As an alternative embodiment, as shown in fig. 2, the duplex disconnecting link 31 is provided with a self-returning mechanism 32, and when the worker releases the duplex disconnecting link 31, the duplex disconnecting link 31 can automatically open the normally-open measuring line 2 and automatically close the normally-closed grounding line 1; the potential safety hazard caused by damage of the current measuring device 4 due to long-term electrification and disconnection of a grounding loop caused by forgetting switching on after the grounding current of the iron core is measured by a worker can be effectively prevented.
Alternatively, the self-return mechanism 32 employs a spring return structure that is currently available for circuit switches.
As an alternative embodiment, the current measuring device 4 is provided as a magnetoelectric ammeter 41.
The magnetoelectric ammeter 41 comprises a measuring circuit, a measuring mechanism and an indicating device, adopts a milliammeter with the measuring range of 500 milliamperes, can bear 600V voltage and 500mA current, has the precision of 1.5 percent, completely meets the measurement of the unbalanced current of the iron core, and has more accurate measuring data.
As an alternative embodiment, referring to fig. 4, the magnetoelectric ammeter 41 is provided with a dial 411 capable of displaying the measured ground current.
A transparent window 412 is provided at a position corresponding to the dial 411 on the magnetoelectric ammeter 41, and the measured ground current can be directly read.
Example 3:
example 3 differs from example 2 in that:
as shown in fig. 3, the switching device 3 includes a ground line switch 34 and a measurement line switch 33.
The grounding circuit switch 34 is arranged on the normally closed grounding circuit 1 and is connected in parallel relative to the normally open measuring circuit 2, and the grounding circuit switch 34 is a normally closed switch and is in a closed state under a normal state, so that the normally closed grounding circuit 1 is ensured to be grounded stably.
The measurement circuit switch 33 is arranged on the normally-off measurement circuit 2, the measurement circuit switch 33 is a normally-off switch and is in a disconnected state in a normal state, the normally-off measurement circuit 2 is guaranteed to be disconnected, and the magnetoelectric ammeter is free of electricity in the normal state.
As an optional embodiment, the grounding line switch 34 is provided with a self-returning mechanism 32, the measurement line switch 33 is provided with the self-returning mechanism 32, and after the grounding current measurement operation of the worker is completed, the grounding line switch 34 and the measurement line switch 33 automatically return to the normal state; on the one hand, the operation is simplified, and on the other hand, the use safety is ensured.
Example 4
Example 4 is based on any of examples 1 to 3:
the utility model provides a transformer core grounding current measuring device, which comprises a protective device 6, wherein a transformer core grounding current measuring structure is arranged in the protective device 6, as shown in figure 4.
The shielding device 6 may be configured as an open type shielding device located at the upper side of the transformer core ground current measuring structure.
The protective device 6 can also be a closed protective device, and the grounding current measuring structure of the transformer core is positioned at the inner side of the closed protective device.
The protection device 6 is used for protection of rain, snow and the like, ensures safe operation of equipment and prolongs the service life of the equipment.
As an optional embodiment, the protection device 6 includes a housing, and the housing is made of an aluminum alloy material, so that the appearance design is beautiful and applicable.
The transformer core grounding current measuring structure is characterized in that an installation cavity is arranged inside the shell, and the transformer core grounding current measuring structure is arranged in the installation cavity.
The casing is provided with an opening communicated with the installation cavity, the opening is matched with the transparent window 412 of the magnetoelectric ammeter 41 in shape and size, and after the magnetoelectric ammeter 41 is installed, sealing treatment is performed between the opening and the transparent window 412.
As shown in fig. 4, the switching device 3 employs a duplex switch 31, a switch operating handle 311 is disposed on the outer side of the housing, the switch operating handle 311 is located right below the housing, and the switch end of the duplex switch 31 can be controlled to be closed on different switch-on ends by the switch operating handle 311.
As an alternative embodiment, the housing is provided with a first connection terminal 61 and a second connection terminal 62 that are electrically connected to both ends of the normally closed ground line 1, respectively.
The first connection end 61 is used for connecting the transformer core grounding lead-out 51, the second connection end 62 is used for connecting the transformer core grounding 52, and the connection mode of the first connection end 61 and the second connection end 62 can be non-detachable connection or detachable connection.
As an alternative embodiment, the first connection end 61 is detachably connected to the transformer core ground lead-out 51 by the first threaded fastener 7.
The second connection 62 is detachably connected to the transformer core ground 52 by a second threaded fastener 8.
Example 4, using the measurement structure of example 2, is taken as an example:
the operation method for installing the transformer core grounding current measuring device on the traditional transformer core grounding structure comprises the following steps:
sawing off the transformer core grounding flat iron according to the specification and the size of the device, forming a transformer core grounding lead-out 51 by the upper core grounding flat iron after sawing off, drilling and punching the end part of the transformer core grounding lead-out 51, and connecting a first connecting end 61 and the end part of the upper core grounding flat iron by adopting a first threaded fastener 7; and forming the transformer core grounding 52 by the sawn lower core grounding flat iron, drilling and drilling the end part of the transformer core grounding 52, and connecting the second connecting end 62 with the end part of the lower core grounding flat iron by adopting a second threaded fastener 8 to finish the installation.
The working process of the installed transformer core grounding current measuring device is as follows:
when measurement is needed, the disconnecting link operating handle 311 is held to lift the disconnecting link outwards, current flows through the magnetoelectric ammeter 41, the numerical value can be read, the disconnecting link operating handle 311 is released after reading, the duplex disconnecting link 31 is automatically closed due to the action of the self-returning mechanism 32, the recovery operation of the equipment is guaranteed, and the reading time is not more than 10 seconds in order to prevent the magnetoelectric ammeter 41 from being damaged due to long-term electrification; in order to ensure the normal operation of the loop, further inspection is required and the duplex disconnecting link 31 is ensured to be switched on in place.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.
Claims (10)
1. The utility model provides a transformer core ground current measurement structure which characterized in that, includes normally closed ground connection circuit, normally open measurement circuit and switching device, wherein:
one end of the normally closed grounding circuit is connected with the transformer iron core in a grounding leading-out manner, and the other end of the normally closed grounding circuit is grounded;
the two ends of the normally-closed measuring circuit are connected and arranged on the normally-closed grounding circuit, and a current measuring device is arranged on the normally-closed measuring circuit and used for measuring grounding current;
the switch device is arranged on the normally closed grounding circuit and the normally open measuring circuit to control the normally closed grounding circuit and the normally open measuring circuit to be opened or closed.
2. The transformer core ground current measurement structure according to claim 1, wherein the switching device comprises a duplex disconnecting link capable of simultaneously controlling the normally closed ground line to be opened and the normally open measurement line to be closed.
3. The transformer core ground current measurement structure according to claim 2, wherein said double-link knife-switch is provided with a self-return mechanism to enable said normally closed ground line to be automatically closed.
4. The transformer core grounding current measuring structure according to claim 1, wherein the current measuring device is provided as a magnetoelectric ammeter.
5. The transformer core grounding current measuring structure according to claim 4, wherein the magnetoelectric ammeter is provided with a dial for display of measured current information;
and a transparent window for reading the information of the measured current is arranged on the magnetoelectric ammeter corresponding to the position of the dial.
6. The transformer core ground current measurement structure of claim 4, wherein said magnetoelectric ammeter is provided as a milliammeter.
7. A transformer core grounding current measuring device, characterized by comprising a protective device, wherein the transformer core grounding current measuring structure according to any one of claims 1-6 is arranged in the protective device.
8. The transformer core ground current measurement device according to claim 7, wherein the shielding device comprises a housing, a mounting chamber is disposed inside the housing, and the transformer core ground current measurement structure is disposed in the mounting chamber.
9. The transformer core grounding current measuring device according to claim 8, wherein the housing is provided with a first connecting end and a second connecting end which are respectively electrically connected with two ends of the normally closed grounding circuit, the first connecting end is used for connecting a transformer core grounding lead-out, and the second connecting end is used for connecting a transformer core grounding.
10. The transformer core grounding current measuring device according to claim 9, wherein the first connecting end is detachably connected with the transformer core grounding lead-out through a first threaded fastener;
the second connecting end and the transformer core are detachably connected through a second threaded fastener.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121483389.1U CN215575334U (en) | 2021-06-30 | 2021-06-30 | Transformer core grounding current measuring structure and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121483389.1U CN215575334U (en) | 2021-06-30 | 2021-06-30 | Transformer core grounding current measuring structure and device |
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| Publication Number | Publication Date |
|---|---|
| CN215575334U true CN215575334U (en) | 2022-01-18 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202121483389.1U Active CN215575334U (en) | 2021-06-30 | 2021-06-30 | Transformer core grounding current measuring structure and device |
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| CN (1) | CN215575334U (en) |
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2021
- 2021-06-30 CN CN202121483389.1U patent/CN215575334U/en active Active
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