CN106291048A - A kind of current boost device, current transformer and current test method - Google Patents
A kind of current boost device, current transformer and current test method Download PDFInfo
- Publication number
- CN106291048A CN106291048A CN201610613966.1A CN201610613966A CN106291048A CN 106291048 A CN106291048 A CN 106291048A CN 201610613966 A CN201610613966 A CN 201610613966A CN 106291048 A CN106291048 A CN 106291048A
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- Prior art keywords
- current
- boost device
- magnetic core
- current transformer
- secondary winding
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- 238000010998 test method Methods 0.000 title claims abstract description 9
- 238000004804 winding Methods 0.000 claims abstract description 72
- 230000005291 magnetic effect Effects 0.000 claims abstract description 33
- 238000005259 measurement Methods 0.000 claims abstract description 14
- 229910000976 Electrical steel Inorganic materials 0.000 claims abstract description 9
- 239000000463 material Substances 0.000 claims abstract description 6
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 24
- 229910052742 iron Inorganic materials 0.000 claims description 12
- 239000004020 conductor Substances 0.000 claims description 6
- 230000005294 ferromagnetic effect Effects 0.000 claims description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical group [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 3
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 3
- 229910000828 alnico Inorganic materials 0.000 claims description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 3
- 229910052782 aluminium Inorganic materials 0.000 claims description 3
- -1 aluminium-nickel-cobalt Chemical compound 0.000 claims description 3
- 229910052802 copper Inorganic materials 0.000 claims description 3
- 239000010949 copper Substances 0.000 claims description 3
- 229910000938 samarium–cobalt magnet Inorganic materials 0.000 claims description 3
- 230000035699 permeability Effects 0.000 abstract description 2
- 238000000034 method Methods 0.000 description 6
- 238000012360 testing method Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 229910001172 neodymium magnet Inorganic materials 0.000 description 2
- QJVKUMXDEUEQLH-UHFFFAOYSA-N [B].[Fe].[Nd] Chemical group [B].[Fe].[Nd] QJVKUMXDEUEQLH-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/0092—Arrangements for measuring currents or voltages or for indicating presence or sign thereof measuring current only
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/18—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using inductive devices, e.g. transformers
- G01R15/183—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using inductive devices, e.g. transformers using transformers with a magnetic core
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
- Transformers For Measuring Instruments (AREA)
Abstract
This application discloses a kind of current boost device, current transformer and current test method, wherein, current boost device is applied to current transformer, the Secondary Winding open circuit of current transformer, including: for the wire connecting portion being connected with the Secondary Winding of current transformer；Deviate from current transformer one end to be connected with wire connecting portion, and be wound in the input coil of magnetic core side and be wound in the output winding of magnetic core opposite side；The material of magnetic core is silicon steel sheet；The measurement portion being connected with output winding head and the tail；Input coil is preset value with the turn ratio of output winding, and preset value is more than 1.Current boost device is utilized to avoid the electric current of the Secondary Winding side due to current transformer too small and the amplitude of electric current to be measured and the situation of phase place cannot be measured.And owing to the material of magnetic core is silicon steel sheet, silicon steel sheet has higher resistivity and maximum permeability, advantageously reduce the loss current of magnetic core, thus reduce the loss of magnetic core, and then the Current amplifier ability of motor current lifting device.
Description
Technical field
The application relates to current phase field of measuring technique, more particularly, it relates to a kind of current boost device, electric current are mutual
Sensor and current test method.
Background technology
In power system, current transformer is to ensure that accurate measurement and the important component of protection correct operation, also
Being the main connecting element once protected with secondary automatization in transformer substation system, the safe operation to power system has direct shadow
Ring.Its primary structure as it is shown in figure 1, include iron core-closed T and be wound in described iron core-closed T side a winding W1 and
It is wound in Secondary Winding W2 of described iron core-closed T opposite side；A described winding W1 is for being serially connected in the circuit of electric current to be measured
In, described Secondary Winding W2 is closed loop winding, for electric current to be measured being converted to small area analysis to detect.
The number of turn of a described winding W1 is a lot of less compared to the number of turn of Secondary Winding W2, and it is mutual that this allows for general electric current
The no-load voltage ratio of sensor is very big (generally more than 2500/1)；And due in power system, due to line length, transmission capacity with
And the problem such as the intrinsic parameter of circuit, cause the receiving end of circuit to produce overvoltage, therefore often become at receiving end in ultra-high/extra-high voltage
The circuit tail end shunt reactor in power station, but this method can make the capacity current of line-to-ground with and anti-offset, make
The electric current obtaining described secondary winding in current transformer W2 one end is too small, thus cannot measure amplitude and the phase place of electric current to be measured；Separately
Outer for short haul circuits and the low-pressure system of large-scale substation, equally exist Secondary Winding W2 one end of described current transformer
The too small problem of electric current.
Summary of the invention
For solving above-mentioned technical problem, the invention provides a kind of current boost device, current transformer and testing current
Method, to realize the purpose of the Secondary Winding electric current of motor current transformer.
For realizing above-mentioned technical purpose, embodiments provide following technical scheme:
A kind of current boost device, is applied to current transformer, the Secondary Winding open circuit of described current transformer, including:
For the wire connecting portion being connected with the Secondary Winding of described current transformer；
Deviate from described current transformer one end to be connected with described wire connecting portion, and be wound in magnetic core side input coil and
It is wound in the output winding of described magnetic core opposite side；
The material of described magnetic core is silicon steel sheet；
The measurement portion being connected with described output winding head and the tail；
Described input coil is preset value with the turn ratio of described output winding, and described preset value is more than 1.
Preferably, the span of described preset value is 10-30, including endpoint value.
Preferably, described wire connecting portion is binding post.
Preferably, described measurement portion is vector measurement collar.
Preferably, described vector measurement collar is the wire being connected with described output winding head and the tail.
Preferably, described wire is copper conductor or aluminum conductor or silver wire.
Preferably, described magnetic core is neodymium-iron-boron ferromagnetic core or samarium cobalt magnet magnetic core or aluminium-nickel-cobalt magnetic ferromagnetic core.
A kind of current transformer, including:
Iron core-closed；
It is wound in a winding of described iron core-closed side；
It is wound in the Secondary Winding of described iron core-closed opposite side, the outfan of described Secondary Winding and current boost device
Connect；
Described current boost device is the current boost device described in any of the above-described embodiment.
A kind of current test method, including:
Current transformer is utilized to access current circuit to be measured, it is thus achieved that switching current, described current transformer is above-mentioned enforcement
Current transformer described in example；
Current phase table is utilized to measure the phase place of described switching current.
From technique scheme it can be seen that embodiments provide a kind of current boost device, current transformer
And current test method, wherein, the wire connecting portion of described current boost device is connected with the Secondary Winding of described current transformer, institute
The electric current of the Secondary Winding side stating current transformer flows into described current boost device through described wire connecting portion, is then passed through institute
State input coil and output winding electric current is changed to realize the electric current of the Secondary Winding side to described current transformer
Lifting.Owing to the input coil of described hoisting module and the turn ratio of output winding are more than 1, therefore there is current boost and make
With, utilize described current boost device avoid the electric current of the Secondary Winding side due to described current transformer too small and cannot
Measure the amplitude of electric current to be measured and the situation of phase place.
Further, owing to the material of described magnetic core is silicon steel sheet, silicon steel sheet has higher resistivity and maximum permeability, has
It is beneficial to reduce the loss current of magnetic core, thus reduces the loss of magnetic core, and then promote the Current amplifier of described current boost device
Ability.
Accompanying drawing explanation
In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing
In having technology to describe, the required accompanying drawing used is briefly described, it should be apparent that, the accompanying drawing in describing below is only this
Inventive embodiment, for those of ordinary skill in the art, on the premise of not paying creative work, it is also possible to according to
The accompanying drawing provided obtains other accompanying drawing.
Fig. 1 is the structural representation of current transformer of the prior art；
The structural representation of a kind of current boost device that the embodiment that Fig. 2 is the application provides；
Fig. 3 is the equivalent circuit basal orientation spirogram of current transformer；
Fig. 4 is current transformer vector diagram；
The schematic flow sheet of a kind of current test method that the embodiment that Fig. 5 is the application provides.
Detailed description of the invention
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clear, complete
Describe, it is clear that described embodiment is only a part of embodiment of the present invention rather than whole embodiments wholely.Based on
Embodiment in the present invention, it is every other that those of ordinary skill in the art are obtained under not making creative work premise
Embodiment, broadly falls into the scope of protection of the invention.
The embodiment of the present application provides a kind of current boost device, is applied to current transformer, described current transformer
Secondary Winding is opened a way, as in figure 2 it is shown, include:
For the wire connecting portion 10 being connected with the Secondary Winding of described Current Transmit；
Deviate from described Current Transmit one end with described wire connecting portion 10 to be connected, and be wound in the input line of magnetic core 20 side
Enclose (the most shown in Figure 2) and be wound in the output winding (the most shown in Figure 2) of described magnetic core 20 opposite side；
The material of described magnetic core 20 is silicon steel sheet；
The measurement portion 30 being connected with described output winding head and the tail；
Described input coil is preset value with the turn ratio of described output winding, and described preset value is more than 1.
It should be noted that in actual application, the Secondary Winding open circuit of described Current Transmit refers to former
The outfan carrying out interconnective Secondary Winding disconnects.So that described current boost device 100 is applied to described electric current is mutual
Time in sensor CT, the outfan of described wire connecting portion 10 with the Secondary Winding disconnected can be connected, and described input coil is common
Formed new loop (the Secondary Winding open circuit of the most described Current Transmit do not imply that with described current boost device 100
Work process after connection is opened a way), the electric current transmitted from described Current Transmit with reception, this electric current is through described
The enlarging function of the output electric current of the Secondary Winding to Current Transmit is realized after the conversion of output winding.Utilize described electric current
It is too small and cannot measure to be measured that lifting device 100 avoids the electric current of the Secondary Winding side due to described Current Transmit
The amplitude of electric current and the situation of phase place.
To be analyzed for the model of described Current Transmit below, as shown in Figure 3 and Figure 4, accompanying drawing 3 is described electricity
The equivalent circuit basal orientation spirogram of current transformer CT, accompanying drawing 4 is the vector diagram of described Current Transmit；Label Es in figure represents
Secondary induced potential；Us represents secondary load voltage；Ip represents primary current；Ip/Kn represents secondary total current；Is represents secondary
Electric current；Ie represents exciting current；N1 represents the primary winding number of turn；N2 represents the secondary coil number of turn；Kn=N2/N1 represents described electricity
The no-load voltage ratio of current transformer；Zb represents secondary coil load reactance (in low magnetism leakage current transformer, Zb is negligible)；Ze represents excitation
Impedance.
It can be seen that use pcrmeability and the higher silicon steel sheet of resistivity to fill as described current boost from Fig. 3 and Fig. 4
The magnetic core 20 put can effectively reduce the loss current of magnetic core 20, just forces when the ratio that Ie accounts for total current Ip/Kn is the least
The near magnifying state without any loss, advantageously reduces the loss of magnetic core 20, and then promotes described current boost device 100
Current amplifier ability.
On the basis of above-described embodiment, in an embodiment of the application, the span of described preset value is 10-
30, including endpoint value.In actual application, depending on the concrete value of described preset value can be according to actual demand, at this
In one embodiment of application, described preset value is 10；In another embodiment of the application, described preset value can also be
20 or 30.This is not limited by the application, concrete depending on practical situation.
On the basis of above-described embodiment, in another embodiment of the application, described wire connecting portion 10 is binding post.
Described measurement portion 30 is vector measurement collar.
In actual application, it is generally required to three-phase (A phase, B phase and the C phase) electric current in power system is carried out respectively
Test.So it is accomplished by utilizing three Current Transmits the A phase current in power system, B phase current and C phase current to be changed
For small area analysis, current phase table is utilized to test after the lifting respectively through three described current boost devices 100 the most again,
Realize the testing current in power system.
On the basis of above-described embodiment, in another embodiment of the application, described vector measurement collar for institute
State the wire that output winding head and the tail connect.
Described wire can be copper conductor or aluminum conductor or silver wire, and the concrete kind of described wire is not done by the application
Limit, concrete depending on practical situation.
On the basis of any of the above-described embodiment, in the further embodiment of the application, described magnetic core 20 is neodymium iron boron
Magnet magnetic core or samarium cobalt magnet magnetic core or aluminium-nickel-cobalt magnetic ferromagnetic core.The kind of described magnetic core 20 is not limited by the application, tool
Depending on stereoscopic practical situation.
In sum, the embodiment of the present application provides a kind of current boost device 100, wherein, described current boost device
The wire connecting portion 10 of 100 is connected with the Secondary Winding of described Current Transmit, the Secondary Winding side of described Current Transmit
Electric current flow into described current boost device 100 through described wire connecting portion 10, be then passed through described three hoisting module with realize
The A phase of Secondary Winding side, B phase and the lifting of C phase current to described Current Transmit.Defeated due to described hoisting module
The turn ratio entering coil and output winding is more than 1, therefore has current boost effect, utilizes described current boost device 100 to keep away
The electric current having exempted from the Secondary Winding side due to described Current Transmit too small and cannot measure electric current to be measured amplitude and
The situation of phase place.
Accordingly, the embodiment of the present application additionally provides a kind of Current Transmit, including:
Iron core-closed；
It is wound in a winding of described iron core-closed side；
It is wound in the Secondary Winding of described iron core-closed opposite side, the outfan of described Secondary Winding and current boost device
100 connect；
Described current boost device 100 is the current boost device 100 described in any of the above-described embodiment.
In sum, the embodiment of the present application provides a kind of current boost device 100 and Current Transmit, wherein, institute
The Secondary Winding of the wire connecting portion 10 and described Current Transmit of stating current boost device 100 is connected, described Current Transmit
The electric current of Secondary Winding side flow into described current boost device 100 through described wire connecting portion 10, be then passed through described three
Hoisting module is to realize the A phase of Secondary Winding side, B phase and the lifting of C phase current to described Current Transmit.Due to institute
The turn ratio of the input coil and output winding of stating hoisting module is more than 1, therefore has current boost effect, utilizes described electric current
It is too small and cannot measure to be measured that lifting device 100 avoids the electric current of the Secondary Winding side due to described Current Transmit
The amplitude of electric current and the situation of phase place.
Accordingly, the embodiment of the present application additionally provides a kind of current test method, as it is shown in figure 5, include:
S101: utilize Current Transmit to access current circuit to be measured, it is thus achieved that switching current, described Current Transmit is
Current Transmit described in any of the above-described embodiment；
S102: utilize current phase table to measure the phase place of described switching current.
In sum, the embodiment of the present application provides a kind of current boost device 100, Current Transmit and testing current
Method, wherein, the wire connecting portion 10 of described current boost device 100 is connected with the Secondary Winding of described Current Transmit, described
The electric current of the Secondary Winding side of Current Transmit flows into described current boost device 100 through described wire connecting portion 10, then
Through described three hoisting module to realize the A phase of Secondary Winding side, B phase and the C phase current to described Current Transmit
Lifting.Owing to the input coil of described hoisting module and the turn ratio of output winding are more than 1, therefore there is current boost and make
With, utilize described current boost device 100 to avoid the electric current of the Secondary Winding side due to described Current Transmit too small
And the amplitude of electric current to be measured and the situation of phase place cannot be measured.
In this specification, each embodiment uses the mode gone forward one by one to describe, and what each embodiment stressed is and other
The difference of embodiment, between each embodiment, identical similar portion sees mutually.
Described above to the disclosed embodiments, makes professional and technical personnel in the field be capable of or uses the present invention.
Multiple amendment to these embodiments will be apparent from for those skilled in the art, as defined herein
General Principle can realize without departing from the spirit or scope of the present invention in other embodiments.Therefore, the present invention
It is not intended to be limited to the embodiments shown herein, and is to fit to and principles disclosed herein and features of novelty phase one
The widest scope caused.
Claims (9)
1. a current boost device, it is characterised in that be applied to current transformer, the Secondary Winding of described current transformer is opened
Road, including:
For the wire connecting portion being connected with the Secondary Winding of described current transformer；
Deviate from described current transformer one end to be connected with described wire connecting portion, and be wound in input coil and the winding of magnetic core side
Output winding in described magnetic core opposite side；
The material of described magnetic core is silicon steel sheet；
The measurement portion being connected with described output winding head and the tail；
Described input coil is preset value with the turn ratio of described output winding, and described preset value is more than 1.
Current boost device the most according to claim 1, it is characterised in that the span of described preset value is 10-30,
Including endpoint value.
Current boost device the most according to claim 1, it is characterised in that described wire connecting portion is binding post.
Current boost device the most according to claim 1, it is characterised in that described measurement portion is vector measurement collar.
Current boost device the most according to claim 4, it is characterised in that described vector measurement collar is and described output
The wire that coil head and the tail connect.
Current boost device the most according to claim 5, it is characterised in that described wire is copper conductor or aluminum conductor or silver
Wire.
7. according to the current boost device described in any one of claim 1-6, it is characterised in that described magnetic core is ndfeb magnet
Magnetic core or samarium cobalt magnet magnetic core or aluminium-nickel-cobalt magnetic ferromagnetic core.
8. a current transformer, it is characterised in that including:
Iron core-closed；
It is wound in a winding of described iron core-closed side；
Being wound in the Secondary Winding of described iron core-closed opposite side, the outfan of described Secondary Winding is with current boost device even
Connect；
Described current boost device is the current boost device described in any one of claim 1-7.
9. a current test method, it is characterised in that including:
Current transformer is utilized to access current circuit to be measured, it is thus achieved that switching current, described current transformer is described in claim 8
Current transformer；
Current phase table is utilized to measure the phase place of described switching current.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610613966.1A CN106291048A (en) | 2016-07-28 | 2016-07-28 | A kind of current boost device, current transformer and current test method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610613966.1A CN106291048A (en) | 2016-07-28 | 2016-07-28 | A kind of current boost device, current transformer and current test method |
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| Publication Number | Publication Date |
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| CN106291048A true CN106291048A (en) | 2017-01-04 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610613966.1A Pending CN106291048A (en) | 2016-07-28 | 2016-07-28 | A kind of current boost device, current transformer and current test method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112164559A (en) * | 2020-09-03 | 2021-01-01 | 中冶天工集团有限公司 | Self-adaptive variable-range current transformer |
Citations (4)
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|---|---|---|---|---|
| JPH11337590A (en) * | 1998-05-28 | 1999-12-10 | Tempearl Ind Co Ltd | Direct current detecting device |
| CN201251622Y (en) * | 2008-09-19 | 2009-06-03 | 陕西电力科学研究院 | Heavy current up-flow aggregate unit for field test of 750v current transformator |
| CN103336188A (en) * | 2013-05-30 | 2013-10-02 | 国家电网公司 | Current boosting apparatus suitable for GIS equipment |
| CN103675386A (en) * | 2013-11-12 | 2014-03-26 | 中铁二十一局集团电务电化工程有限公司 | Upflow transformer for low-voltage energization |
-
2016
- 2016-07-28 CN CN201610613966.1A patent/CN106291048A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11337590A (en) * | 1998-05-28 | 1999-12-10 | Tempearl Ind Co Ltd | Direct current detecting device |
| CN201251622Y (en) * | 2008-09-19 | 2009-06-03 | 陕西电力科学研究院 | Heavy current up-flow aggregate unit for field test of 750v current transformator |
| CN103336188A (en) * | 2013-05-30 | 2013-10-02 | 国家电网公司 | Current boosting apparatus suitable for GIS equipment |
| CN103675386A (en) * | 2013-11-12 | 2014-03-26 | 中铁二十一局集团电务电化工程有限公司 | Upflow transformer for low-voltage energization |
Non-Patent Citations (1)
| Title |
|---|
| 詹姆斯 H.哈洛主编，保定天威保变电气股份有限公司 译: "《电力变压器工程》", 30 April 2016, 机械工业出版社 * |
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|---|---|---|---|---|
| CN112164559A (en) * | 2020-09-03 | 2021-01-01 | 中冶天工集团有限公司 | Self-adaptive variable-range current transformer |
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