CN206300992U - For the earth current monitoring of transformer core and current-limiting apparatus - Google Patents
For the earth current monitoring of transformer core and current-limiting apparatus Download PDFInfo
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- CN206300992U CN206300992U CN201620758046.4U CN201620758046U CN206300992U CN 206300992 U CN206300992 U CN 206300992U CN 201620758046 U CN201620758046 U CN 201620758046U CN 206300992 U CN206300992 U CN 206300992U
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Abstract
A kind of earth current for transformer core is monitored and current-limiting apparatus,Include the current monitoring sensor for being set to be connected with the earth electrode of transformer core and for picking up the earth current signal of transformer core,Be set to be connected with the earth electrode of transformer core and earth-continuity protection for transformer core Overvoltage protecting unit D1,Be set to be connected with the earth electrode of transformer core and for transformer core earth current current-limiting protection resistance-type protection device,It is set to be input into current monitoring sensor input signal as control signal and to resistance-type protection device the signal controller T of control signal,Overvoltage protecting unit D1 and resistance-type protection device are connected with current monitoring sensor series again after being set to be connected in parallel,By Overvoltage protecting unit D1,The mandatory conducting protection of ground connection to transformer core,By current monitoring sensor,Resistance-type protection device and signal controller T,According to the size of the earth current of transformer core,The current-limiting protection of the resistance-type protection device to the earth current of transformer core of different stage is opened by signal controller T,No longer only use Overvoltage protecting unit D1,It is achieved that earth current is limited in into below 100mA automatically,Improve to transformer safety performance.
Description
First, technical field
The utility model is related to a kind of earth current to monitor and current-limiting apparatus, especially a kind of connecing for transformer core
Earth-current is monitored and current-limiting apparatus.
2nd, background technology
When transformer is linked into power circuit, it is necessary to transformer a little and grounding connection, when connecing occurs in transformer
During earth fault, the electric current in transformer core grounding copper bar increases and more than 100mA, by the ground connection electricity to transformer core
Stream monitoring and current limliting, are the important means for ensureing transformer safety, thus be accordingly used in the earth current monitoring of transformer core and limit
Stream device is a kind of important transformer part, existing for the earth current monitoring of transformer core and current-limiting apparatus
In, the earth current also only to transformer core is monitored, also without a kind of earth current prison for transformer core
Survey and current-limiting apparatus, so as to the earth current to transformer core is monitored and automatic current limiting switching, automatically by earth current
Below 100mA is limited in, is improve to transformer safety performance.
3rd, the content of the invention
Object of the present utility model is a kind of for the earth current monitoring of transformer core and current-limiting apparatus.
In order to overcome above-mentioned technical disadvantages, the purpose of this utility model to be to provide a kind of ground connection electricity for transformer core
Stream monitoring and current-limiting apparatus, it is achieved that earth current is limited in into below 100mA automatically, improve to transformer safety
Energy.
To reach above-mentioned purpose, the utility model is adopted the technical scheme that：Include and be set to and transformer core
Earth electrode is connected and for picking up the current monitoring sensor of the earth current signal of transformer core, being set to and transformation
The earth electrode of device iron core connect and for transformer core earth-continuity protection Overvoltage protecting unit D1, be set to
The earth electrode of transformer core is connected and the resistance-type for the current-limiting protection of the earth current of transformer core protects dress
Put, be set to current monitoring sensor input signal as control signal and to resistance-type protection device input control signal
Signal controller T, Overvoltage protecting unit D1 and resistance-type protection device be set to be connected in parallel after again with current monitoring sensor
It is connected in series.
Due to devising current monitoring sensor, Overvoltage protecting unit D1, resistance-type protection device and signal controller T,
By Overvoltage protecting unit D1, the mandatory conducting protection of ground connection to transformer core, by current monitoring sensor, resistance-type
Protection device and signal controller T, according to the size of the earth current of transformer core, open not at the same level by signal controller T
The current-limiting protection of earth current of other resistance-type protection device to transformer core, no longer only uses Overvoltage protecting unit D1,
It is achieved that earth current is limited in into below 100mA automatically, improve to transformer safety performance.
The utility model is devised, and the earth-continuity protection of transformer core is carried out and by resistance according to by diode
The mode of current-limiting protection of the earth current of transformer core is carried out current monitoring sensor, Overvoltage protecting unit D1, resistance
Formula protection device and signal controller T-phase connect.
The utility model is devised, and resistance-type protection device is set to include the resistance of at least two tandems connection.
The utility model is devised, and current monitoring sensor is set to include current monitoring sensor CT1 and electric current prison
Sensor CT2 is surveyed, resistance-type protection device is set to include current-limiting resistance R1, current-limiting resistance R2, current-limiting resistance R3, current limliting electricity
Resistance R4, control contactor J1, control contactor J2, control contactor J3, control contactor J4 and control contactor J5,
One end port of current monitoring sensor CT1 is set to be connected simultaneously with one end port of current monitoring sensor CT2
And the other end port of current monitoring sensor CT2 is respectively set to positive pole, the control contactor J1 with Overvoltage protecting unit D1
One end port and current-limiting resistance R1 one end port connection, the other end port of current-limiting resistance R1 is respectively set to be connect with control
One end port of tentaculum J2 and one end port of current-limiting resistance R2 connect and the other end port of current-limiting resistance R2 is respectively provided with
It is to be connected with one end port of control contactor J3 and one end port of current-limiting resistance R3, the other end port point of current-limiting resistance R3
Be not set to be connected with one end port of control contactor J4 and one end port of current-limiting resistance R4 and current-limiting resistance R4 it is another
One end port is respectively set to be connected with one end port of control contactor J5, the negative pole of Overvoltage protecting unit D1, control contact
The other end port of device J1, the other end port of control contactor J2, the other end port of control contactor J3, control contactor
The other end port of J4 and the other end port of control contactor J5 are respectively set to the one of electrode with transformer core
Connect and the other end port of current monitoring sensor CT1 be set to be connected with the other in which electrode of transformer core,
The signal output port of current monitoring sensor CT1 and the signal output port of current monitoring sensor CT2 be respectively set to
The input port of signal controller T is connected and the output port of signal controller T is respectively set to control contactor J1's
Control port, the control port of control contactor J2, the control port of control contactor J3, the control port of control contactor J4
Control port with control contactor J5 is connected.
The utility model is devised, and the range of current monitoring sensor CT1 is set to 0-1A and current monitoring sensor
The range of CT2 is set to 0-10A.
The utility model is devised, control contactor J1, control contactor J2, control contactor J3, control contactor J4
Relay is set to control contactor J5.
The utility model is devised, and Overvoltage protecting unit D1 is set to pressure limiting diode.
The utility model is devised, signal controller T be set to include A D sampling units module, message handler, after
Electrical control unit module, display signal element module and alarm output unit module, the signal of current monitoring sensor CT1 are defeated
The signal output port of exit port and current monitoring sensor CT2 be respectively set to A D sampling unit modules input port
Connect and A the output port of D sampling unit modules be set to be connected with the input port of message handler, message handler
The output port input port that is respectively set to the input port of relay control unit module, display signal element module
With the output port of the connection of the input port of alarm output unit module and relay control unit module be respectively set to
The control port of control contactor J1, the control port of control contactor J2, the control port of control contactor J3, control contact
The control port connection of the control port and control contactor J5 of device J4.
The utility model is devised, and manual control module and automatic control module switching are provided with signal controller T
Button.
In the technical program, the earth-continuity for carrying out transformer core by diode is protected and become by resistance
The current-limiting protection of the earth current of depressor iron core is important technical characteristic, in the earth current monitoring for transformer core and limit
Flow in the technical field of device, with novelty, creative and practicality, the term in the technical program all can be with this
Patent document in technical field is explained and understood.
4th, illustrate
In order to illustrate more clearly of the utility model embodiment or technical scheme of the prior art, below will be to embodiment
Or the accompanying drawing to be used needed for description of the prior art is briefly described, it should be apparent that, drawings in the following description are only
It is some embodiments of the present utility model, for those of ordinary skill in the art, is not paying the premise of creative work
Under, other accompanying drawings can also be obtained according to these accompanying drawings.
Fig. 1 is schematic diagram of the present utility model：
Fig. 2 is the block diagram of signal controller T of the present utility model.
5th, specific embodiment
According to guidelines for examination, the utility model is used such as " have ", "comprising" and " including " term should
It is interpreted as the presence or addition for not allotting one or more of the other element or its combination.
It is term " " center ", " on ", D score, "left", "right", " perpendicular, it is necessary to explanation in description of the present utility model
Directly ", the orientation or position relationship of the instruction such as " level ", " interior ", " outward " are, based on orientation shown in the drawings or position relationship, to be only
Described with simplified for the ease of description the utility model, must had rather than the device or element for indicating or implying meaning specific
Orientation, with specific azimuth configuration and operation, therefore it is not intended that to limitation of the present utility model.Additionally, term " the
One ", " second ", " the 3rd " are only used for describing purpose, and it is not intended that indicating or implying relative importance.
, it is necessary to explanation, unless otherwise clearly defined and limited, term " is pacified in description of the present utility model
Dress ", " connected ", " connection " should be interpreted broadly, for example, it may be fixedly connected, or be detachably connected, or integratedly
Connection；Can mechanically connect, or electrically connect；Can be joined directly together, it is also possible to be indirectly connected to by intermediary,
Can be two connections of element internal.For the ordinary skill in the art, above-mentioned art can be understood with concrete condition
Concrete meaning of the language in the utility model.
As long as additionally, technical characteristic involved in the utility model different embodiments disclosed below is each other
Not constituting conflict can just be combined with each other.
Below in conjunction with the accompanying drawing in the utility model embodiment, the technical scheme in the utility model embodiment is carried out
Clearly and completely describe, it is clear that described embodiment is only a part of embodiment of the utility model, rather than whole
Embodiment.Based on the embodiment in the utility model, those of ordinary skill in the art are not under the premise of creative work is made
The every other embodiment for being obtained, belongs to the scope of the utility model protection.
Fig. 1 is one embodiment of the present utility model, and the present embodiment is illustrated with reference to accompanying drawing, includes current monitoring biography
Sensor CT1, current monitoring sensor CT2, current-limiting resistance R1, current-limiting resistance R2, current-limiting resistance R3, current-limiting resistance R4, control connect
Tentaculum J1, control contactor J2, control contactor J3, control contactor J4, control contactor J5, Overvoltage protecting unit D1 and letter
Number controller T,
One end port of current monitoring sensor CT1 is set to be connected simultaneously with one end port of current monitoring sensor CT2
And the other end port of current monitoring sensor CT2 is respectively set to positive pole, the control contactor J1 with Overvoltage protecting unit D1
One end port and current-limiting resistance R1 one end port connection, the other end port of current-limiting resistance R1 is respectively set to be connect with control
One end port of tentaculum J2 and one end port of current-limiting resistance R2 connect and the other end port of current-limiting resistance R2 is respectively provided with
It is to be connected with one end port of control contactor J3 and one end port of current-limiting resistance R3, the other end port point of current-limiting resistance R3
Be not set to be connected with one end port of control contactor J4 and one end port of current-limiting resistance R4 and current-limiting resistance R4 it is another
One end port is respectively set to be connected with one end port of control contactor J5, the negative pole of Overvoltage protecting unit D1, control contact
The other end port of device J1, the other end port of control contactor J2, the other end port of control contactor J3, control contactor
The other end port of J4 and the other end port of control contactor J5 are respectively set to the one of electrode with transformer core
Connect and the other end port of current monitoring sensor CT1 be set to be connected with the other in which electrode of transformer core,
The signal output port of current monitoring sensor CT1 and the signal output port of current monitoring sensor CT2 be respectively set to
The input port of signal controller T is connected and the output port of signal controller T is respectively set to control contactor J1's
Control port, the control port of control contactor J2, the control port of control contactor J3, the control port of control contactor J4
Control port with control contactor J5 is connected.
In the present embodiment, the range of current monitoring sensor CT1 is set to 0-1A and current monitoring sensor CT2
Range is set to 0-10A.
In the present embodiment, control contactor J1, control contactor J2, control contactor J3, control contactor J4 and control
Contactor J5 processed is set to relay.
In the present embodiment, Overvoltage protecting unit D1 is set to pressure limiting diode.
In the present embodiment, signal controller T be set to include A D sampling units module 1, message handler 2, relay
Device control unit module 3, display signal element module 4 and alarm output unit module 5, the signal of current monitoring sensor CT1
The signal output port of output port and current monitoring sensor CT2 be respectively set to A D sampling units module 1 input
Mouthful connection and A the output port of D sampling units module 1 be set to be connected with the input port of message handler 2, at information
The output port for managing device 2 is respectively set to and the input port of relay control unit module 3, display signal element module 4
The input port connection of input port and alarm output unit module 5 and the output port point of relay control unit module 3
Control port, the control port of control contactor J2, the control end of control contactor J3 with control contactor J1 are not set to
The control port connection of mouth, the control port of control contactor J4 and control contactor J5.
In the present embodiment, manual control module and automatic control module switching push button are provided with signal controller T.
When signal controller T is connected to manual control signal, acquiescence J1 switch closures.Into MANUAL CONTROL mode.Pass through
Button controls 4 branch roads respectively.After each switching confirms J2-J5 controlled outputs, J1 points is opened, and prevents disconnection.
When signal controller T is connected to automatic control signal, into automatic control mode.In circuit board, interface is set, if
Put a current setting value I0, by I0Control switching resistance value.As actual measurement I<During 100mA, J1 closures, J2-J5 disconnects, current limliting
Unit does not work.As actual measurement I>During 100mA, after J2 closures 1S, J1 disconnects.R1 seals in earth-return circuit, and whether monitoring I is less than
100mA。
If I is less than 100mA, the state is kept, and alarm.
If still greater than 100mA, after J3 closures 1S, J2 disconnects I, R1+R2 seals in earth-return circuit, and whether monitoring I is less than
100mA。
If I is less than 100mA, the state is kept, and alarm.
If still greater than 100mA, after J4 closures 1S, J3 disconnects I, R1+R2+R3 seals in earth-return circuit, and whether monitoring I is less than
100mA。
If I is less than 100mA, the state is kept, and alarm.
If still greater than 100mA, after J5 closures 1S, J4 disconnects I, and R1+R2+R3+R4 seals in earth-return circuit.Whether I is small for monitoring
In 100mA.
When flow-restriction both end voltage exceedes setting value, ground protection is turned on by Overvoltage protecting unit D1.
The utility model has lower feature：
1st, due to devising current monitoring sensor, Overvoltage protecting unit D1, resistance-type protection device and signal controller
T, by Overvoltage protecting unit D1, the mandatory conducting protection of ground connection to transformer core, by current monitoring sensor, resistance
Formula protection device and signal controller T, according to the size of the earth current of transformer core, open different by signal controller T
Current-limiting protection of the resistance-type protection device of rank to the earth current of transformer core, no longer only uses Overvoltage protecting unit
D1, it is achieved that earth current is limited in into below 100mA automatically, improves to transformer safety performance.
2nd, due to devising current monitoring sensor CT1 and current monitoring sensor CT2, by current monitoring sensor
The classification range of CT1 and current monitoring sensor CT2, improves the precision of the earth current signal to picking up transformer core.
3rd, due to devising resistance-type protection device, by current-limiting resistance and relay, improve to transformer core
The unfailing performance of the current limliting of earth current.
4th, due to devise current-limiting resistance R1, current-limiting resistance R2, current-limiting resistance R3, current-limiting resistance R4, control contactor J1,
Control contactor J2, control contactor J3, control contactor J4 and control contactor J5, by current-limiting resistance R1, current-limiting resistance
R2, current-limiting resistance R3 and current-limiting resistance R4, realize classification current limliting, improve to the current limliting of the earth current of transformer core
Precision.
5th, due to devising technical characteristic of the present utility model, the work of set in the independent of technical characteristic and each other
With, being shown by experiment, property indices of the present utility model are at least 1.7 times of existing property indices, are led to
Crossing assessment has good market value.
It is also other to be protected with transformer core is carried out by diode earth-continuity and transformation is carried out by resistance
The technical characteristic of the connection of the current-limiting protection of the earth current of device iron core is all one of embodiment of the present utility model, and more than
Each technical characteristic of the embodiment can be combined arbitrarily, to meet Patent Law, patent regulation and guidelines for examination
Requirement, the no longer embodiment to all possible combination of each technical characteristic in above-described embodiment is all described.
Therefore it is every to include setting in the earth current monitoring and current-limiting apparatus technical field for transformer core
It is to be connected with the earth electrode of transformer core and passed for picking up the current monitoring of the earth current signal of transformer core
Sensor, it is set to be connected with the earth electrode of transformer core and the overvoltage for the earth-continuity protection of transformer core is protected
Cells D 1 is protected, is set to be connected with the earth electrode of transformer core and the current limliting for the earth current of transformer core is protected
The resistance-type protection device of shield, it is set to current monitoring sensor input signal as control signal and protects resistance-type fill
Put the signal controller T of input control signal, Overvoltage protecting unit D1 and resistance-type protection device be set to be connected in parallel after again
The technology contents being connected with current monitoring sensor series are all in protection domain of the present utility model.
Claims (9)
1. a kind of for the earth current monitoring of transformer core and current-limiting apparatus, it is characterized in that：Include and be set to and transformation
The earth electrode of device iron core is connected and for picking up the current monitoring sensor of the earth current signal of transformer core, setting
Be be connected with the earth electrode of transformer core and for transformer core earth-continuity protection Overvoltage protecting unit D1,
Be set to be connected with the earth electrode of transformer core and for transformer core earth current current-limiting protection resistance
Formula protection device, it is set to current monitoring sensor input signal as control signal and is input into resistance-type protection device control
The signal controller T of signal processed, Overvoltage protecting unit D1 and resistance-type protection device are supervised with electric current again after being set to be connected in parallel
Survey sensor series connection.
2. according to claim 1 for the earth current monitoring of transformer core and current-limiting apparatus, it is characterized in that：According to
The limit of the earth current of transformer core is protected and carried out by resistance to the earth-continuity for carrying out transformer core by diode
The mode for flowing protection interconnects current monitoring sensor, Overvoltage protecting unit D1, resistance-type protection device and signal controller T-phase
Connect.
3. according to claim 1 for the earth current monitoring of transformer core and current-limiting apparatus, it is characterized in that：Resistance
Formula protection device is set to include the resistance of at least two tandems connection.
4. according to claim 1 for the earth current monitoring of transformer core and current-limiting apparatus, it is characterized in that：Electric current
Monitoring sensor is set to include current monitoring sensor CT1 and current monitoring sensor CT2, and resistance-type protection device is set
To include current-limiting resistance R1, current-limiting resistance R2, current-limiting resistance R3, current-limiting resistance R4, control contactor J1, control contactor
J2, control contactor J3, control contactor J4 and control contactor J5,
One end port of current monitoring sensor CT1 is set to be connected with one end port of current monitoring sensor CT2 and electricity
The other end port of stream monitoring sensor CT2 be respectively set to the positive pole of Overvoltage protecting unit D1, control contactor J1 one
One end port connection of end port and current-limiting resistance R1, the other end port of current-limiting resistance R1 is respectively set to and control contactor
One end port connection of one end port of J2 and current-limiting resistance R2 and the other end port of current-limiting resistance R2 be respectively set to
One end port connection of one end port and current-limiting resistance R3 of control contactor J3, the other end port of current-limiting resistance R3 sets respectively
Be set to be connected with one end port of control contactor J4 and one end port of current-limiting resistance R4 and current-limiting resistance R4 the other end
Port is respectively set to be connected with one end port of control contactor J5, the negative pole of Overvoltage protecting unit D1, control contactor J1
Other end port, the other end port of control contactor J2, the other end port of control contactor J3, control contactor J4
The other end port of other end port and control contactor J5 is respectively set to be connected with one of electrode of transformer core
And the other end port of current monitoring sensor CT1 is set to be connected with the other in which electrode of transformer core, electric current
The signal output port of monitoring sensor CT1 and the signal output port of current monitoring sensor CT2 are respectively set to and signal
The control that the input port connection of controller T and the output port of signal controller T are respectively set to control contactor J1
Port, the control port of control contactor J2, the control port of control contactor J3, the control port of control contactor J4 and control
The control port connection of contactor J5 processed.
5. according to claim 4 for the earth current monitoring of transformer core and current-limiting apparatus, it is characterized in that：Electric current
The range of monitoring sensor CT1 is set to 0-1A and the range of current monitoring sensor CT2 is set to 0-10A.
6. according to claim 4 for the earth current monitoring of transformer core and current-limiting apparatus, it is characterized in that：Control
Contactor J1, control contactor J2, control contactor J3, control contactor J4 and control contactor J5 are set to relay.
7. according to claim 4 for the earth current monitoring of transformer core and current-limiting apparatus, it is characterized in that：Overvoltage
Protection location D1 is set to pressure limiting diode.
8. according to claim 4 for the earth current monitoring of transformer core and current-limiting apparatus, it is characterized in that：Signal
Controller T be set to include A D sampling unit modules（1）, message handler（2）, relay control unit module（3）, it is aobvious
Show signal element module（4）With alarm output unit module（5）, the signal output port and electric current of current monitoring sensor CT1
The signal output port of monitoring sensor CT2 be respectively set to A D sampling unit modules（1）Input port connection and A
D sampling unit modules（1）Output port be set to and message handler（2）Input port connection, message handler（2）'s
Output port is respectively set to and relay control unit module（3）Input port, display signal element module（4）Input
Port and alarm output unit module（5）Input port connection and relay control unit module（3）Output port point
Control port, the control port of control contactor J2, the control end of control contactor J3 with control contactor J1 are not set to
The control port connection of mouth, the control port of control contactor J4 and control contactor J5.
9. according to claim 4 for the earth current monitoring of transformer core and current-limiting apparatus, it is characterized in that：In letter
Manual control module and automatic control module switching push button are provided with number controller T.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620758046.4U CN206300992U (en) | 2016-07-19 | 2016-07-19 | For the earth current monitoring of transformer core and current-limiting apparatus |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620758046.4U CN206300992U (en) | 2016-07-19 | 2016-07-19 | For the earth current monitoring of transformer core and current-limiting apparatus |
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| CN206300992U true CN206300992U (en) | 2017-07-04 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108711840A (en) * | 2018-05-30 | 2018-10-26 | 湖南大学 | A kind of fault current restraining device and method |
-
2016
- 2016-07-19 CN CN201620758046.4U patent/CN206300992U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108711840A (en) * | 2018-05-30 | 2018-10-26 | 湖南大学 | A kind of fault current restraining device and method |
| CN108711840B (en) * | 2018-05-30 | 2019-06-18 | 湖南大学 | A kind of fault current inhibition device and method |
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