CN108767815A - Electromagnetic potential transformer auto by pass harmonic elimination apparatus - Google Patents
Electromagnetic potential transformer auto by pass harmonic elimination apparatus Download PDFInfo
- Publication number
- CN108767815A CN108767815A CN201810785444.9A CN201810785444A CN108767815A CN 108767815 A CN108767815 A CN 108767815A CN 201810785444 A CN201810785444 A CN 201810785444A CN 108767815 A CN108767815 A CN 108767815A
- Authority
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- China
- Prior art keywords
- potential transformer
- electromagnetic potential
- connect
- controllable silicon
- fuse
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000008030 elimination Effects 0.000 title claims abstract description 14
- 238000003379 elimination reaction Methods 0.000 title claims abstract description 14
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 20
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 20
- 239000010703 silicon Substances 0.000 claims abstract description 20
- 239000013307 optical fiber Substances 0.000 claims abstract description 5
- 230000005611 electricity Effects 0.000 claims description 3
- 230000005350 ferromagnetic resonance Effects 0.000 abstract description 8
- 238000007599 discharging Methods 0.000 abstract description 6
- 230000000694 effects Effects 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- 230000005622 photoelectricity Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000013016 damping Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000003760 hair shine Effects 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/04—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for transformers
- H02H7/05—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for transformers for capacitive voltage transformers, e.g. against resonant conditions
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/40—Arrangements for reducing harmonics
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Emergency Protection Circuit Devices (AREA)
- Supply And Distribution Of Alternating Current (AREA)
Abstract
The invention discloses a kind of electromagnetic potential transformer auto by pass harmonic elimination apparatus, including electromagnetic potential transformer PT, fuse FU, bypass resistance R and two controllable silicon SCRs, bypass resistance R connects with two antiparallel controllable silicon SCRs, then with the circuit in parallel after electromagnetic potential transformer PT and its fuse FU that connects, one phase of one end access electric system that the fuse FU after parallel connection is connect with bypass resistance R, the tail end of other end electromagnetic potential transformer PT are connect with the earth, and Current Transmit is provided on connecting line；The secondary of Current Transmit connects Light-emitting diode LED, the light that Light-emitting diode LED is sent out is transmitted through the optical fiber to photodiode LCR, and the one end photodiode LCR connect with the gate pole of the controllable silicon SCR, connect with the anode of controllable silicon SCR after other end concatenation current-limiting resistance r.Direct-to-ground capacitance charging or discharging current when the present invention can effectively inhibit ferromagnetic resonance, bypass single-phase earthing to disappear solves the problems, such as that voltage transformer and fuse frequency are molten, ruins frequently.
Description
Technical field
The invention belongs to distribution protection technical fields, and in particular to a kind of direct-to-ground capacitance charging and discharging currents flowing through PT from
Dynamic shunting device.
Background technology
The electromagnetic potential transformer of power distribution network（PT）And fuse frequency ruins phenomenon and takes place frequently, not only increase operation and maintenance at
This, and the safe and stable operation of power grid and equipment is caused and is seriously threatened.
Experts and scholars both domestic and external have carried out a large amount of research to ferromagnetic resonance, and have developed corresponding device, in system
Also certain effect is achieved in operation.These suppression measures are broadly divided into two classes：One time neutral point accesses harmonic elimination resistance（SiC
Resonance eliminator）, secondary angular aperture access microcomputer harmonic elimination device（Secondary resonance elimination device）.It was verified that common SiC once disappears
Humorous device can eliminate most of ferromagnetic resonance, and still, resonance eliminator of SiC influences voltage measurement accuracy, and there is lifting PT
The problem of tail end voltage, or even the tail end insulation breakdown of semi-insulating PT can be caused, form serious security risk.Secondary harmonic elimination dress
Set using the angle voltage that is open as criterion, need the data of certain period of time can just calculate as a result, act delay it is longer,
100ms or more；Because voltage jump, the charging and discharging currents of system direct-to-ground capacitance can only flow through PT and once return when single-phase earthing disappears
Road can not only cause PT fuse blows, or even PT is caused to burn when intermittence ground connection frequently occurs, and secondary resonance elimination device
It is unable to continuous action, is not worked substantially to such intermittent ground connection.It is more than 68% power transformation according to the statistics of national grid
The neutral point for medium-voltage distribution net side of standing is connected in earth-free mode, and ferromagnetic resonance frequently occurs, electromagnetic potential transformer and its molten
Disconnected device is frequently molten, it is serious to ruin phenomenon frequently, and loss is very big, and waste is a large amount of artificial, and seriously affects the safe and reliable of medium voltage distribution network
Operation.
Invention content
The technical problem to be solved by the present invention is to overcome defect described above, provide a kind of simple in structure, quick, high
The electromagnetic potential transformer auto by pass harmonic elimination apparatus of effect.
In order to solve the problems, such as techniques described above, electromagnetic potential transformer auto by pass harmonic elimination apparatus of the present invention,
Including electromagnetic potential transformer PT, fuse FU, bypass resistance R and two controllable silicon SCRs, the bypass resistance R and two
The series connection of antiparallel controllable silicon SCR, then with the electricity after the electromagnetic potential transformer PT and its fuse FU that connects
Road is in parallel, and the other end after a phase of electric system, parallel connection is accessed in one end that the fuse FU after parallel connection is connect with bypass resistance R
The tail end of the electromagnetic potential transformer PT is connect with the earth, the connection that the electromagnetic potential transformer PT is connect with the earth
Current Transmit is provided on line；The secondary of the Current Transmit connects Light-emitting diode LED, the light emitting diode
The light that LED is sent out is transmitted through the optical fiber to photodiode LCR, the door of the one end the photodiode LCR and the controllable silicon SCR
It is connect with the anode of the controllable silicon SCR after pole connection, other end concatenation current-limiting resistance r.
Preferably, the value of bypass resistance R of the present invention is between 50k Ω -200k Ω.
Beneficial effects of the present invention：The present invention has structure type simple and reliable, can effectively inhibit ferromagnetic resonance, bypass
The charging and discharging currents of system direct-to-ground capacitance when single-phase earthing disappears, the frequency that solves electromagnetic potential transformer and its fuse is molten,
Frequency ruins problem.
Description of the drawings
Fig. 1 is the theory of constitution figure of the present invention.
Specific implementation mode
Invention is further described in detail with reference to the accompanying drawings and examples.
Electromagnetic potential transformer auto by pass harmonic elimination apparatus of the present invention, including it is electromagnetic potential transformer PT, molten
Disconnected device FU, bypass resistance R and two controllable silicon SCRs, the bypass resistance R connect with two antiparallel controllable silicon SCRs, then
With the circuit in parallel after the electromagnetic potential transformer PT and its fuse FU that connects, the fuse FU after parallel connection and side
The tail of electromagnetic potential transformer PT described in the other end after a phase of electric system, parallel connection is accessed in one end of road resistance R connections
End is connect with the earth, and Current Transmit is provided on the connecting line that the electromagnetic potential transformer PT is connect with the earth；Institute
It states the secondary of Current Transmit and connects Light-emitting diode LED, the light that the Light-emitting diode LED is sent out is transmitted through the optical fiber to photoelectricity
Diode LCR, the one end the photodiode LCR is connect with the gate pole of the controllable silicon SCR, the other end concatenates current-limiting resistance r
It is connect afterwards with the anode of the controllable silicon SCR.
Preferably, the value of bypass resistance R of the present invention is between 50k Ω -200k Ω.
Embodiment：The three-phase circuit of electromagnetic potential transformer auto by pass harmonic elimination apparatus of the present invention is full symmetric,
Referring to Fig. 1, the circuit in figure inside dotted line frame is three-phase common circuit, and the circuit outside dotted line frame is three-phase independent circuits.
The present invention is to flow through the direct-to-ground capacitance charging and discharging currents automatic bypass device of PT, bypass resistance R and two inverse parallels
Controllable silicon SCR series connection, then with the circuit in parallel after electromagnetic potential transformer PT and its serial fuse FU, it is in parallel after electricity
One phase of one end access electric system that road fuse FU is connect with current-limiting resistance R, other end electromagnetic potential mutual inductance after parallel connection
The tail end of device PT is connect with the earth, and Current Transmit is provided on connecting line；The secondary of Current Transmit connects light-emitting diodes
Pipe LED, the light that LED is sent out are transmitted through the optical fiber to photodiode LCR, the gate pole of the one end photodiode LCR and controllable silicon SCR
Connection, the other end are connect after concatenating current-limiting resistance r with the anode of SCR.
Under normal circumstances, the exciting current very little of electromagnetic potential transformer PT, the secondary output of Current Transmit is not
It is enough that Light-emitting diode LED, photodiode LCR is driven not to turn on, controllable silicon SCR is off state；When between system generation
When having a rest property ground connection or ferromagnetic resonance, electromagnetic potential transformer PT will flow through prodigious saturation exciting current or system
The secondary current driving Light-emitting diode LED of the charging and discharging currents of direct-to-ground capacitance, Current Transmit shines, two pole of triggering photoelectricity
Pipe LCR is connected by illumination, and controllable silicon SCR is in several us（Microsecond）Conducting, bypass resistance R are put into immediately in time, are formed strong
Damping effectively inhibits ferromagnetic resonance and causes the electric current of electromagnetic potential transformer PT, avoids ferromagnetic resonance and fuse blows.
Embodiments disclosed above is only intended to help to illustrate the present invention, and that there is no detailed descriptionthes is all for preferred embodiment
Details does not limit the invention to the specific embodiments described.Obviously, according to the content of this specification, can make very much
These embodiments are chosen and specifically described to modifications and variations, this specification, is in order to preferably explain the principle of the present invention and reality
Border is applied, to enable skilled artisan to be best understood by and utilize the present invention, as long as having used the above
Structure should all fall into protection scope of the present invention.
Claims (2)
1. a kind of electromagnetic potential transformer auto by pass harmonic elimination apparatus, including electromagnetic potential transformer PT, fuse FU, side
Road resistance R and two controllable silicon SCRs, which is characterized in that the bypass resistance R connects with two antiparallel controllable silicon SCRs, so
Afterwards with the circuit in parallel after the electromagnetic potential transformer PT and its fuse FU that connects, it is in parallel after fuse FU with
Electromagnetic potential transformer PT described in the other end after a phase of electric system, parallel connection is accessed in one end of bypass resistance R connections
Tail end is connect with the earth, and Current Transmit is provided on the connecting line that the electromagnetic potential transformer PT is connect with the earth；
The secondary of the Current Transmit connects Light-emitting diode LED, and the light that the Light-emitting diode LED is sent out is transmitted through the optical fiber to light
Electric diode LCR, the one end the photodiode LCR is connect with the gate pole of the controllable silicon SCR, the other end concatenates current-limiting resistance
It is connect with the anode of the controllable silicon SCR after r.
2. electromagnetic potential transformer auto by pass harmonic elimination apparatus according to claim 1, which is characterized in that the bypass electricity
The value of R is hindered between 50k Ω -200k Ω.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810785444.9A CN108767815B (en) | 2018-07-17 | 2018-07-17 | Automatic bypass resonance elimination device of electromagnetic voltage transformer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810785444.9A CN108767815B (en) | 2018-07-17 | 2018-07-17 | Automatic bypass resonance elimination device of electromagnetic voltage transformer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108767815A true CN108767815A (en) | 2018-11-06 |
| CN108767815B CN108767815B (en) | 2024-02-02 |
Family
ID=63970303
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810785444.9A Active CN108767815B (en) | 2018-07-17 | 2018-07-17 | Automatic bypass resonance elimination device of electromagnetic voltage transformer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108767815B (en) |
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2018
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| CN2777723Y (en) * | 2005-03-17 | 2006-05-03 | 西安交通大学 | Power frequency resonance aliminating apparatus |
| CN1776986A (en) * | 2005-11-21 | 2006-05-24 | 华北电力大学（北京） | Controllable damp device of ferromagnetic resonance for electromagnetic voltage transformer for distribution network |
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| CN203376375U (en) * | 2013-06-07 | 2014-01-01 | 国家电网公司 | Graded insulation electromagnetic type PT primary side current monitoring device |
| CN203859512U (en) * | 2014-05-28 | 2014-10-01 | 安徽中电电气有限公司 | PT arc-extinguishing protective device |
| CN104377680A (en) * | 2014-11-21 | 2015-02-25 | 国家电网公司 | Secondary alternating-current resonance elimination device used for electromagnetic type voltage transformer |
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| Publication number | Publication date |
|---|---|
| CN108767815B (en) | 2024-02-02 |
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