CN109638777A - A kind of electric railway house transformer protection system - Google Patents
A kind of electric railway house transformer protection system Download PDFInfo
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- CN109638777A CN109638777A CN201811556715.XA CN201811556715A CN109638777A CN 109638777 A CN109638777 A CN 109638777A CN 201811556715 A CN201811556715 A CN 201811556715A CN 109638777 A CN109638777 A CN 109638777A
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- current
- transformer
- relay
- speed switch
- electric current
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- 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
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Protection Of Transformers (AREA)
Abstract
The embodiment of the present invention provides a kind of electric railway house transformer protection system, comprising: high-speed switch, house transformer, current transformer, relay and controller；Wherein, the primary side current of house transformer and secondary side current are transformed into the primary side measurement electric current of same size by current transformer respectively and secondary side measures electric current；Relay judges whether generation shorted-turn fault according to difference current, and difference current is that primary side measures electric current and secondary side measures difference between currents；If generation shorted-turn fault, the interior contacts closure of relay are known in relay judgement；Controller sends trip command to high-speed switch after the interior contacts closure for knowing relay；High-speed switch completes trip operation after receiving trip command.The embodiment of the present invention can cancel existing house transformer " fuse+on-load switch " protected mode, improve the ability of house transformer safe operation, the effectively generation of the safety accidents such as prevention fire for transformer, explosion.
Description
Technical field
The present embodiments relate to power protection technology fields, and in particular to a kind of electric railway house transformer protection
System.
Background technique
Traction Substation of Electric Railway (subregion institute, switching station, AT institute) is used with power supply and is supplied power with double circuit, usual a-road-through
It crosses comprehensive through track and takes electricity, i.e., using three-phase 10/0.4kV house transformer as main power supply in electric substation, another way is from leading
Draw net and take electricity, i.e., using three-phase or single-phase 27.5/0.4 (0.23) kV house transformer as power supply hot standby in electric substation.
The higher hamonic wave as existing for tractive power supply system, split-phase overvoltage, switching impulse overvoltage, net voltage fluctuation dodge
The operating conditions such as change, system high-frequency resonance bring totally unfavorable influence to house transformer, cause to take from Traction networks used in electricity
Transformer is prone to short trouble.
Aiming at the problem that taking the house transformer of electricity to be prone to failure on the net, general speed electric railway house transformer one
As protected using fuse, high-speed railway generallys use the combination protected mode of " fuse+on-load switch ".But due to
27.5kV house transformer capacity is small, conductor cross-section is small, field strength is high, umber of turn is more, rated current is small, therefore " fuse+negative
The combination protected mode of lotus switch " is not able to satisfy the protection demand of 27.5kV house transformer still, the protection demand of transformer and
Existing protective device does not match that, causes protective device after transformer fault that cannot act rapidly, so that failure propagation, gives iron
Road safe operation brings larger impact.
At present to the most reload temperature control device of 27.5kV dry type house transformer, to transformer temperature caused by fault
Degree is abnormal to play certain forewarning function.Domestic relevant enterprise had once carried out the research of dry-type transformer optical fiber temperature-measurement, to change used
Transformer coil carries out multipoint temperature monitoring, but can not realize and link with existing protective device.
In recent years house transformer burn explosion accident it is commonplace, bring larger impact to safe railway operation.I
State's electric railway has 60 years history, and house transformer protection is still blank, although some scientific research personnel have done some grind
Study carefully work, but has not yet to see ideal effect.
Summary of the invention
To solve the problem of that existing house transformer not can be carried out effective protection when short trouble occurs, the present invention is real
It applies example and a kind of electric railway house transformer protection system is provided.
Electric railway house transformer provided in an embodiment of the present invention protects system, comprising: high-speed switch, transformation used
Device, current transformer, relay and controller；Wherein, the current transformer is used for the primary side of the house transformer
Electric current and secondary side current are transformed into the primary side measurement electric current and secondary side measurement electric current of same size respectively；The relay
Device be used for according to difference current judge whether occur shorted-turn fault, the difference current be the primary side measure electric current with
The secondary side measures difference between currents；If generation shorted-turn fault is known in relay judgement, the relay it is interior
Portion's junction closure, and the information that its interior contacts is closed is passed into the controller；The controller be used for know it is described
After the interior contacts closure of relay, Xiang Suoshu high-speed switch sends trip command；The high-speed switch is used for receiving
After stating trip command, trip operation is completed.
Optionally, the relay is specific to use when for judging whether to occur shorted-turn fault according to difference current
In: if the difference current is zero, judgement is known, and shorted-turn fault does not occur；Otherwise, generation turn-to-turn short circuit is known in judgement
Failure.
Optionally, the current transformer is Hall transformer.
Optionally, the primary side measurement electric current and secondary side measurement electric current are mA grades.
Optionally, the high-speed switch is the high-speed switch based on vortex driving principle.
Optionally, the high-speed switch completes trip operation in 10ms.
Optionally, the high-speed switch is also used to complete tripping in the trip command for receiving the controller transmission
After movement, Xiang Suoshu controller sends status information.
Optionally, the high-speed switch is also used to when external short circuit failure occurs, and completes trip operation.
Optionally, the house transformer is 27.5kV house transformer.
The embodiment of the present invention passes through electric to the primary side current of house transformer and secondary side respectively using current transformer
Stream is converted, and is judged whether that shorted-turn fault occurs according to difference current, if shorted-turn fault occurs for judgement, is controlled
High-speed switch processed trips, and such protection scheme can cancel existing electric railway house transformer, and " fuse+load is opened
Close " protected mode, improves the ability of house transformer safe operation, effectively prevents the safety accidents such as fire for transformer, explosion
Occur.
Detailed description of the invention
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below
There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is the present invention
Some embodiments for those of ordinary skill in the art without creative efforts, can also basis
These attached drawings obtain other attached drawings.
Fig. 1 is electric railway house transformer protection system structure diagram provided in an embodiment of the present invention.
Specific embodiment
In order to make the object, technical scheme and advantages of the embodiment of the invention clearer, below in conjunction with the embodiment of the present invention
In attached drawing, the technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described embodiment is
A part of the embodiment of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, those of ordinary skill in the art
Every other embodiment obtained without creative efforts, shall fall within the protection scope of the present invention.
Fig. 1 is electric railway house transformer protection system structure diagram provided in an embodiment of the present invention.Such as Fig. 1 institute
Show, the system comprises: high-speed switch 1, house transformer 2, current transformer 3, relay 4 and controller 5；Wherein, described
Current transformer 3 is used to the primary side current of the house transformer 2 and secondary side current being transformed into same size respectively
Primary side measures electric current and secondary side measures electric current；The relay 4 is used to be judged whether according to difference current that turn-to-turn to occur
Short trouble, the difference current are that the primary side measures electric current and the secondary side measures difference between currents；If the relay
Generation shorted-turn fault is known in the judgement of device 4, then the interior contacts closure of the relay, and the letter that its interior contacts is closed
Breath passes to the controller 5；The controller 5 is used for after the interior contacts closure for knowing the relay 4, to described fast
Fast switch 1 sends trip command；The high-speed switch 1 is used for after receiving the trip command, completes trip operation.
The current transformer 3 for converting the primary side current of the house transformer 2 and secondary side current respectively
Electric current is measured at the primary side of same size and secondary side measures electric current；The i.e. described current transformer 3 is by house transformer 2
Primary side current is transformed into primary side measurement electric current, and the secondary side current of house transformer 2 is transformed into secondary side measurement electricity
Stream；When house transformer operates normally, the value of the primary side measurement electric current and secondary side measurement electric current is equal.
Electric current is measured according to the primary side and secondary side measurement electric current obtains difference current, and the difference current is
The primary side measurement electric current and the secondary side measure difference between currents, it is possible to understand that, the difference current can be described
Primary side measurement electric current subtracts the result of the secondary side measurement electric current, or the secondary side measurement electric current subtracts described
The result of primary side measurement electric current.In Fig. 1, the difference current is indicated with Id.
The relay 4 is used to be judged whether according to difference current that shorted-turn fault to occur.The value of difference current can be with
Reflect house transformer 2 whether normal operation and whether shorted-turn fault occurs.If the relay 4 judges according to differential
The value of electric current knows generation shorted-turn fault, then the interior contacts closure of the relay 4, and its interior contacts is closed
Information passes to the controller 5.As shown in Figure 1, two piece-root grafting lines of the controller 5 are separately connected 4 interior contacts of relay
Both ends, if therefore relay 4 interior contacts closure, the information that can be closed its interior contacts passes to the controller 5,
Namely controller 5 can know this information.
The controller 5 is used for after the interior contacts closure for knowing the relay 4, and Xiang Suoshu high-speed switch 1 is sent
Trip command.Shorted-turn fault has occurred in the interior contacts closure expression of the relay 4, and therefore, controller 5 is for obtaining
After knowing the interior contacts closure of the relay 4, Xiang Suoshu high-speed switch 1 sends trip command, and control high-speed switch 1 is jumped
Lock movement.
The high-speed switch 1 is used for after the trip command for receiving the transmission of controller 5, completes trip operation, real
The timely disconnection of existing circuit.
The embodiment of the present invention passes through electric to the primary side current of house transformer and secondary side respectively using current transformer
Stream is converted, and is judged whether that shorted-turn fault occurs according to difference current, if shorted-turn fault occurs for judgement, is controlled
High-speed switch processed trips, and such protection scheme can cancel existing electric railway house transformer, and " fuse+load is opened
Close " protected mode, improves the ability of house transformer safe operation, effectively prevents the safety accidents such as fire for transformer, explosion
Occur.
Further, based on the above embodiment, the relay 4 according to difference current for judging whether that turn-to-turn occurs
When short trouble, be specifically used for: if the difference current is zero, judgement is known, and shorted-turn fault does not occur；Otherwise, judge
Know generation shorted-turn fault.
The current transformer 3 for converting the primary side current of the house transformer 2 and secondary side current respectively
Electric current is measured at the primary side of same size and secondary side measures electric current；The difference current is that the primary side measures electric current
Difference between currents are measured with the secondary side；The difference current can reflect whether shorted-turn fault occurs.House transformer 2
When normal operation, primary side measures electric current and the value of secondary side measurement electric current is equal, therefore the difference current is zero；If institute
Turn-to-turn short circuit occurs with transformer 2, then no longer operates normally, the primary side measurement electric current and secondary side measure electric current at this time
It is no longer equal, so that the difference current is not equal to zero.Therefore, according to difference current whether be zero can decide whether occur circle
Between short circuit.
The relay 4 is specifically used for: when for judging whether to occur shorted-turn fault according to difference current if institute
Stating difference current is zero, then judgement is known, and shorted-turn fault does not occur；If the difference current is not zero, generation is known in judgement
Shorted-turn fault.
On the basis of the above embodiments, whether the embodiment of the present invention is by being zero to judge whether to occur according to difference current
Shorted-turn fault improves the rapidity and timeliness of shorted-turn fault judgement.
Further, based on the above embodiment, the current transformer 3 is Hall transformer.
Hall transformer may be implemented for the primary side current of house transformer 2 and secondary side current to be transformed into respectively identical
The primary side measurement electric current and secondary side of size measure electric current, and therefore, the current transformer 3 can choose Hall mutual inductance
Device.
On the basis of the above embodiments, the embodiment of the present invention is by protecting using Hall transformer as current transformer
The acquisition of difference current is hindered.
Further, based on the above embodiment, the primary side measurement electric current and secondary side measurement electric current are mA grades.
The primary side current of the house transformer and secondary side current can be transformed by the current transformer 3 respectively
The mA grade primary side measurement electric current and secondary side of same size measure electric current；The i.e. described primary side measures electric current and described two
The precision of secondary side measurement electric current can achieve mA, thus, it is possible to identify the variation of small difference current, improve transformer guarantor
Resolution capability of the protecting system for shorted-turn fault.
On the basis of the above embodiments, primary side measurement electric current and secondary side measurement electric current are in the embodiment of the present invention
MA grades, tranformer protection system is improved for the resolution capability of shorted-turn fault.
Further, based on the above embodiment, the high-speed switch 1 is the high-speed switch based on vortex driving principle.
Existing on-load switch is generally equipped with simple arc-control device, but its is relatively simple for structure.Such as air pressing type high pressure
On-load switch, the course of work are: when separating brake, under the action of tripping spring, main shaft is rotated clockwise, and on the one hand passes through crank
Slide block mechanism moves up piston, by gas compression；On the other hand the transmission system being made up of two sets of four-bar mechanisms, makes
Main switch knife is first opened, and then arc extinguishing plug-in strip is pushed to open arcing contact, the compressed air in cylinder blows out electric arc by spout.Cause
This, the movement of on-load switch is slower.
And the high-speed switch based on vortex driving principle includes so that moving conductive contact is moved up and down to reach by magnetic flux power
The operating mechanism device of separating brake or closing position and control circuit for controlling operating mechanism device separating brake or feed motion, can
To realize movement of quicking break.
On the basis of the above embodiments, the embodiment of the present invention by using based on vortex driving principle high-speed switch,
Ensured failure occur after quick disconnecting circuit.
Further, based on the above embodiment, the high-speed switch 1 completes trip operation in 10ms.
It is dynamic that high-speed switch used by the embodiment of the present invention based on vortex driving principle can complete tripping in 10ms
Make.
On the basis of the above embodiments, the embodiment of the present invention is dynamic by making high-speed switch complete tripping in 10ms
Make, has further ensured quick disconnecting circuit after failure generation.
Further, based on the above embodiment, the high-speed switch 1 is also used to receiving what the controller 5 was sent
After the trip command completes trip operation, Xiang Suoshu controller 5 sends status information.
The high-speed switch 1 is also used to complete trip operation in the trip command for receiving the transmission of controller 5
Afterwards, Xiang Suoshu controller 5 sends status information, and the status information includes the information that tripping successfully completes, and will trip successfully
Result inform controller 5 so that entire control process is more complete and reliable.
On the basis of the above embodiments, the embodiment of the present invention is sent after tripping is completed to controller by high-speed switch
Status information improves the reliability of system control.
Further, based on the above embodiment, the high-speed switch is also used to when external short circuit failure occurs, and completes to jump
Lock movement.
When external short circuit failure occurs, the high-speed switch 1 based on vortex driving principle trips, can be in 10ms
Interior completion trip operation.
On the basis of the above embodiments, the embodiment of the present invention passes through high-speed switch when external short circuit failure occurs, complete
At trip operation, security performance is further improved.
Further, based on the above embodiment, the house transformer is 27.5kV house transformer.
When 27.5kV house transformer is run, high-precision current transformer 3 is equal by primary side current and secondary side current
It is transformed to mA grades of electric currents, relay 4 judges whether that turn-to-turn short circuit occurs by comparing difference current Id, when there is turn-to-turn short circuit etc.
When failure, 4 interior contacts of relay closure, controller 5 issues trip command to high-speed switch 1, and high-speed switch 10ms completes to jump
Lock, and status information is sent to controller 5；When there is external short circuit failure, high-speed switch 1 is driven using technologically advanced vortex
Dynamic principle, driving switch movement, 10ms complete trip operation.
The embodiment of the present invention improves existing 27.5kV house transformer protection system, provides a kind of electric railway
27.5kV house transformer rapid protection system uses completely new protection complexes, cut-offs using high-speed switch is superior
Ability, the effectively generation of the safety accidents such as prevention fire for transformer, explosion.
Through the above description of the embodiments, those skilled in the art can be understood that each embodiment can
It realizes by means of software and necessary general hardware platform, naturally it is also possible to pass through hardware.
The apparatus embodiments described above are merely exemplary, wherein described, unit can as illustrated by the separation member
It is physically separated with being or may not be, component shown as a unit may or may not be physics list
Member, it can it is in one place, or may be distributed over multiple network units.It can be selected according to the actual needs
In some or all of the modules achieve the purpose of the solution of this embodiment.Those of ordinary skill in the art are not paying creativeness
Labour in the case where, it can understand and implement.
Finally, it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations；Although
Present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that: it still may be used
To modify the technical solutions described in the foregoing embodiments or equivalent replacement of some of the technical features；
And these are modified or replaceed, technical solution of various embodiments of the present invention that it does not separate the essence of the corresponding technical solution spirit and
Range.
Claims (9)
1. a kind of electric railway house transformer protects system characterized by comprising high-speed switch, house transformer, electricity
Current transformer, relay and controller；
Wherein, the current transformer is for the primary side current of the house transformer and secondary side current to be transformed into respectively
The primary side measurement electric current and secondary side of same size measure electric current；
The relay is used to judge whether to occur according to difference current shorted-turn fault, and the difference current is described primary
Side measures electric current and the secondary side measures difference between currents；If generation shorted-turn fault, institute are known in the relay judgement
The interior contacts closure of relay is stated, and the information that its interior contacts is closed is passed into the controller；
The controller is used for after the interior contacts closure for knowing the relay, and Xiang Suoshu high-speed switch sends tripping and refers to
It enables；
The high-speed switch is used for after receiving the trip command, completes trip operation.
2. system according to claim 1, which is characterized in that the relay according to difference current for judging whether
When shorted-turn fault occurs, it is specifically used for:
If the difference current is zero, judgement is known, and shorted-turn fault does not occur；
Otherwise, generation shorted-turn fault is known in judgement.
3. system according to claim 1, which is characterized in that the current transformer is Hall transformer.
4. system according to claim 3, which is characterized in that the primary side measurement electric current and secondary side measure electric current
It is mA grades.
5. system according to claim 1, which is characterized in that the high-speed switch is based on the quick of vortex driving principle
Switch.
6. system according to claim 5, which is characterized in that the high-speed switch completes trip operation in 10ms.
7. system according to claim 1, which is characterized in that the high-speed switch is also used to receiving the controller
After the trip command sent completes trip operation, Xiang Suoshu controller sends status information.
8. system according to claim 6, which is characterized in that the high-speed switch is also used to that external short circuit failure is occurring
When, complete trip operation.
9. system according to claim 1, which is characterized in that the house transformer is 27.5kV house transformer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811556715.XA CN109638777A (en) | 2018-12-19 | 2018-12-19 | A kind of electric railway house transformer protection system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811556715.XA CN109638777A (en) | 2018-12-19 | 2018-12-19 | A kind of electric railway house transformer protection system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109638777A true CN109638777A (en) | 2019-04-16 |
Family
ID=66075585
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811556715.XA Pending CN109638777A (en) | 2018-12-19 | 2018-12-19 | A kind of electric railway house transformer protection system |
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|---|---|---|---|---|
| CN2267567Y (en) * | 1996-08-02 | 1997-11-12 | 阿城继电器三厂 | Differential relay for transformer |
| JPH1189080A (en) * | 1997-09-10 | 1999-03-30 | Toshiba Corp | Protection relay device |
| CN201133924Y (en) * | 2008-01-01 | 2008-10-15 | 浙江广天变压器有限公司 | Differential voltage transformer turn-to-turn short circuit detection device |
| CN201181837Y (en) * | 2008-03-18 | 2009-01-14 | 朱建国 | Differential protective device of transformer |
| CN201515211U (en) * | 2009-09-10 | 2010-06-23 | 西南交通大学 | Electrified railway main-changing and main-protection device suitable for passenger transport private wires |
| CN102096013A (en) * | 2009-12-15 | 2011-06-15 | 西安爱邦电气有限公司 | Single-switch differential protection CT (Current Transformer) wiring correctness analysis method of four-winding conventional transformer |
| CN103063974A (en) * | 2012-12-25 | 2013-04-24 | 广州供电局有限公司 | On-line monitoring method and device of distribution transformer turn-to-turn short circuit |
-
2018
- 2018-12-19 CN CN201811556715.XA patent/CN109638777A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2267567Y (en) * | 1996-08-02 | 1997-11-12 | 阿城继电器三厂 | Differential relay for transformer |
| JPH1189080A (en) * | 1997-09-10 | 1999-03-30 | Toshiba Corp | Protection relay device |
| CN201133924Y (en) * | 2008-01-01 | 2008-10-15 | 浙江广天变压器有限公司 | Differential voltage transformer turn-to-turn short circuit detection device |
| CN201181837Y (en) * | 2008-03-18 | 2009-01-14 | 朱建国 | Differential protective device of transformer |
| CN201515211U (en) * | 2009-09-10 | 2010-06-23 | 西南交通大学 | Electrified railway main-changing and main-protection device suitable for passenger transport private wires |
| CN102096013A (en) * | 2009-12-15 | 2011-06-15 | 西安爱邦电气有限公司 | Single-switch differential protection CT (Current Transformer) wiring correctness analysis method of four-winding conventional transformer |
| CN103063974A (en) * | 2012-12-25 | 2013-04-24 | 广州供电局有限公司 | On-line monitoring method and device of distribution transformer turn-to-turn short circuit |
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Application publication date: 20190416 |
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