CN108631265B - It is a kind of that the series transformer longitudinal differential protecting equipment sentenced and method are joined based on double differential module - Google Patents
It is a kind of that the series transformer longitudinal differential protecting equipment sentenced and method are joined based on double differential module Download PDFInfo
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- CN108631265B CN108631265B CN201710183487.5A CN201710183487A CN108631265B CN 108631265 B CN108631265 B CN 108631265B CN 201710183487 A CN201710183487 A CN 201710183487A CN 108631265 B CN108631265 B CN 108631265B
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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
- H02H7/045—Differential protection of transformers
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Protection Of Transformers (AREA)
- Emergency Protection Circuit Devices (AREA)
- Thermistors And Varistors (AREA)
- Train Traffic Observation, Control, And Security (AREA)
Abstract
The invention discloses a kind of series transformer longitudinal differential protecting equipment sentenced based on double differential module connection and methods, including the first current transformer, the second current transformer and third current transformer；First current transformer and third current transformer are located at the both ends of series transformer primary side winding；Second current transformer is located at series transformer vice-side winding one end；First current transformer and the second current transformer constitute the first differential module, and the electric current of head end electric current and series transformer vice-side winding of first differential module based on series transformer primary side winding carries out differential protection calculating；Third current transformer and the second current transformer constitute the second differential module, and the electric current of tail current and series transformer vice-side winding of second differential module based on series transformer primary side winding carries out differential protection calculating；Any of first differential module and the second differential module meet differential action condition, the movement of series transformer longitudinal difference protection.The present invention can effectively improve the sensitivity of series transformer longitudinal difference protection.
Description
Technical field
The invention belongs to field of power systems, and in particular to a kind of series transformer sentenced based on double differential module connection is vertical poor
Protective device and method.
Background technique
The primary side winding of series transformer does not have neutral point, and the both ends of winding are directly serially connected in power grid.Compared to common
The work characteristics of parallel connection type transformer, series transformer is different, and primary connection type is different.
As shown in Figure 1, the other end directly connects on an end Jie bus of the common each phase winding in each side of parallel connection type transformer
Ground constitutes neutral point.When poor circuit is arranged in common parallel connection type transformer, it is generally bounded on each side one end setting electricity of each phase winding
Current transformer, the electric current that longitudinal difference protection acquires aforementioned currents mutual inductor carry out differential protection calculating.
Shown in Fig. 2 is the situation that conventional longitudinal differential protection method is directly applied to series transformer.As shown in Fig. 2, string
Connection transformer primary winding directly concatenates in the line.CT1, CT2 constitute longitudinal difference protection.When series transformer operates normally, string
The electric current that the primary side winding of connection transformer flows through is equal to line current, and the electric current of CT1, CT2 acquisition is in magnetic balance state.
The situation that series transformer primary side winding breaks down is considered, when fault point occurs close to CT1, i.e., shown in Fig. 2
A point at, the magnetic balance of series transformer differential protection is obviously destroyed at this time, and the sensitivity of longitudinal difference protection is higher；When event
When barrier point is mobile to the source side winding other end from A point, the magnetic balance degree of being damaged of series transformer longitudinal difference protection is gradually reduced.
When fault point occurs in the source side winding other end, i.e., at B point shown in Fig. 2, the magnetic recording level of series transformer longitudinal difference protection at this time
Weighing apparatus is damaged, and degree is slight, and characteristic (is located at the vertical difference of series transformer to protect with fault characteristic at C point shown in Fig. 2 at C point
Protect outside range) it is very nearly the same.Therefore, when being configured according to conventional longitudinal differential protection method, for the primary side winding far from the installation place CT
Failure, longitudinal difference protection sensitivity will be substantially reduced, and have the risk of relay fail.
Summary of the invention
When in order to overcome existing longitudinal differential protection method to be applied to series transformer, the sensitivity of existing part protection zone
Low problem, the present invention propose a kind of based on the double differential module series transformer longitudinal differential protecting equipment sentenced of connection and method, pass through
Series transformer primary side winding both ends electric current is acquired simultaneously, double-current mutual inductor is realized and joins the series transformer longitudinal difference protection sentenced
Method can effectively improve the sensitivity of series transformer longitudinal difference protection.
It realizes above-mentioned technical purpose, reaches above-mentioned technical effect, the invention is realized by the following technical scheme:
It is a kind of that the series transformer longitudinal differential protecting equipment sentenced is joined based on double differential module, including the first current transformer, the
Two current transformers, third current transformer, the first discrimination module and the second discrimination module；First current transformer and
Three current transformers are separately positioned on the both ends of series transformer primary side winding, acquire the head of series transformer primary side winding respectively
Hold electric current and tail current；One end of series transformer vice-side winding is arranged in second current transformer, and acquisition series connection becomes
The electric current of depressor vice-side winding；It is poor that first current transformer, the second current transformer and the first discrimination module constitute first
Dynamic model block, head end electric current of first discrimination module based on collected series transformer primary side winding and series transformer pair side around
The electric current of group carries out differential protection calculating；The third current transformer, the second current transformer and the second discrimination module are constituted
Second differential module, tail current and series transformer of second discrimination module based on collected series transformer primary side winding
The electric current of vice-side winding carries out differential protection calculating；When any of the first differential module and the second differential module meet setting
When differential action condition, the longitudinal difference protection movement of series transformer configuration is controlled.
Further, the head end electric current of the series transformer primary side winding is the secondary current of the first current transformer.
Further, the tail current of the series transformer primary side winding is the secondary current of third current transformer.
Further, first differential module and the first discrimination module and the second discrimination module in the second differential module
Using same or different difference stream and braking threshold computations formula.
It is a kind of to join the series transformer longitudinal differential protection method sentenced based on double differential module, comprising:
(1) head end electric current of series transformer primary side winding, the tail current of series transformer primary side winding are acquired in real time
With the electric current of series transformer vice-side winding；
(2) head end electric current and series-transformer of first differential module based on collected series transformer primary side winding are utilized
The electric current real-time perfoming differential protection of device vice-side winding calculates；
(3) tail current and series-transformer of second differential module based on collected series transformer primary side winding are utilized
The electric current real-time perfoming differential protection of device vice-side winding calculates；
(4) when any of the first differential module and the second differential module meet the differential action condition of setting, control
The longitudinal difference protection movement of series transformer configuration.
Further, the step (1) specifically includes:
1.1 are respectively set the first current transformer and third current transformer at the both ends of series transformer primary side winding,
The head end electric current of series transformer primary side winding and the tail current of series transformer primary side winding are acquired respectively；
1.2 series transformer vice-side winding one end be arranged the second current transformer, acquisition series transformer pair side around
The electric current of group；
Further, the first differential module described in the step (2) includes connection the first current transformer, the second electric current
Mutual inductor and the first discrimination module, head end electric current and string of first discrimination module based on collected series transformer primary side winding
The electric current real-time perfoming differential protection for joining transformer secondary winding calculates；Second differential module includes the third electricity of connection
Current transformer, the second current transformer and the second discrimination module, the second discrimination module are based on collected series transformer primary side
The tail current of winding and the electric current real-time perfoming differential protection of series transformer vice-side winding calculate.
Further, the head end electric current of the series transformer primary side winding is the secondary current of the first current transformer.
Further, the tail current of the series transformer primary side winding is the secondary current of third current transformer.
Further, first differential module and the second differential module are using same or different difference stream and braking door
Sill calculation formula.
Beneficial effects of the present invention:
The present invention propose it is a kind of based on the double differential module series transformer longitudinal differential protecting equipment sentenced of connection and method, by same
When acquire series transformer primary side winding both ends electric current, realize double-current mutual inductor and join the series transformer longitudinal difference protection side sentenced
Method can effectively improve the sensitivity of series transformer longitudinal difference protection.
Detailed description of the invention
Fig. 1 is common parallel connection type transformer and current transformer primary connection figure；
Fig. 2 is the tandem type transformer and current transformer primary connection figure for configuring traditional longitudinal difference protection；
Fig. 3 is to configure double-current mutual inductor to join the tandem type transformer and current transformer primary connection figure sentenced.
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, with reference to embodiments, to the present invention
It is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, it is not used to
Limit the present invention.
Application principle of the invention is explained in detail with reference to the accompanying drawing.
As shown in figure 3, the longitudinal difference protection compared with the CT of the tandem type transformer of traditional longitudinal difference protection configuration, in the present invention
Current transformer has been respectively configured at series transformer primary side winding both ends in method, such as the CT1 and CT3 in Fig. 3.
Embodiment one
A kind of series transformer longitudinal differential protecting equipment sentenced based on double differential module connection, including the first Current Transmit 1,
Second Current Transmit 2, third Current Transmit 3, the first discrimination module and the second discrimination module；First electric current is mutual
Sensor CT1 and third Current Transmit 3 are separately positioned on the both ends of series transformer primary side winding, acquire series-transformer respectively
The head end electric current and tail current of device primary side winding, series transformer primary side winding are linked into route；Second electric current is mutual
One end of series transformer vice-side winding is arranged in sensor CT2, acquires the electric current of series transformer vice-side winding；First electricity
Current transformer CT1, the second Current Transmit 2 and the first discrimination module constitute the first differential module, and the first discrimination module is based on
The head end electric current of collected series transformer primary side winding and the electric current of series transformer vice-side winding carry out differential protection meter
It calculates；The third Current Transmit 3, the second Current Transmit 2 and the second discrimination module the second differential module of composition, first
The electric current of tail current and series transformer vice-side winding of the discrimination module based on collected series transformer primary side winding into
Row differential protection calculates；When any of the first differential module and the second differential module meet the differential action condition of setting,
Control the series transformer configuration longitudinal difference protection movement (control the series transformer configuration longitudinal differential protecting equipment outlet after
Electric appliance conducting, trigger protection recording, protection message up sending etc.).The differential action condition can be in the prior art each
The vertical poor braking characteristic of kind, the longitudinal difference protection movement can use general longitudinal difference protection action behavior in the prior art.
Preferably, the head end electric current of the series transformer primary side winding is the secondary current of the first Current Transmit 1.
Preferably, the tail current of the series transformer primary side winding is the secondary current of third Current Transmit 3.
Preferably, first differential module and the first discrimination module in the second differential module and the second discrimination module are adopted
With same or different difference stream and braking threshold computations formula；The difference stream and braking threshold computations formula can be using existing
There are the difference stream and braking threshold computations formula in technology, does not do specific limitation in the present invention.
In above scheme, by acquiring series transformer primary side winding both ends electric current simultaneously, double-current mutual inductor is realized
Join the series transformer longitudinal differential protection method sentenced, the sensitivity of series transformer longitudinal difference protection can be effectively improved.
Embodiment two
It is a kind of to join the series transformer longitudinal differential protection method sentenced based on double differential module, comprising:
(1) head end electric current of series transformer primary side winding, the tail current of series transformer primary side winding are acquired in real time
With the electric current of series transformer vice-side winding；
(2) head end electric current and series-transformer of first differential module based on collected series transformer primary side winding are utilized
The electric current real-time perfoming differential protection of device vice-side winding calculates；
(3) tail current and series-transformer of second differential module based on collected series transformer primary side winding are utilized
The electric current real-time perfoming differential protection of device vice-side winding calculates；
(4) when any of the first differential module and the second differential module meet the differential action condition of setting, control
The longitudinal difference protection movement of series transformer configuration.
Preferably, the step (1) specifically includes:
1.1 are respectively set the first Current Transmit 1 and third Current Mutual Inductance at the both ends of series transformer primary side winding
Device CT3, for acquiring the head end electric current of series transformer primary side winding and the tail current of series transformer primary side winding respectively；
1.2 are arranged the second Current Transmit 2 in one end of series transformer vice-side winding, for acquiring series transformer
The electric current of vice-side winding；
Preferably, the first differential module described in the step (2) is mutual including the first current transformer of connection, the second electric current
Sensor and the first discrimination module, head end electric current and series connection of first discrimination module based on collected series transformer primary side winding
The electric current real-time perfoming differential protection of transformer secondary winding calculates；Second differential module includes the third electric current of connection
Mutual inductor, the second current transformer and the second discrimination module, the second discrimination module be based on collected series transformer primary side around
The tail current of group and the electric current real-time perfoming differential protection of series transformer vice-side winding calculate.
Preferably, the head end electric current of the series transformer primary side winding is the secondary current of the first Current Transmit 1.
Preferably, the tail current of the series transformer primary side winding is the secondary current of third Current Transmit 3.
Preferably, first differential module and the second differential module using it is identical or difference stream and braking threshold computations
Formula.
Embodiment three
By at the B point in Fig. 2 occur minor failure for, installation site of the fault point B from the first Current Transmit 1 compared with
Far, close to the tail end of series transformer source side winding (i.e. primary side winding).At this point, the vertical poor magnetic balance of the first differential module is by broken
Bad degree is low, if the difference stream I generatedd1Less than the differential threshold I of the first differential module of settingth1, then the first differential module is discontented
Sufficient operation condition；But since fault point B is close to the installation site of third Current Transmit 3, the vertical poor magnetic of the second differential module
Balance is damaged, and degree is obvious, and the difference that the second differential module generates flows Id2The braking threshold I of significantly greater than the second differential moduleth2,
Then the second differential module meets operation condition, i.e. the second differential module compensates for part of first differential module in protection scope
The lower defect of sensitivity, likewise, the first differential module also compensates for portion of second differential module in protection scope
The defect of subregion sensitivity lower (such as A point in Fig. 2).As long as any differential module meets operation condition, double difference dynamic model
The series transformer longitudinal difference protection that block connection is sentenced just acts, to improve the protection spirit of series transformer longitudinal difference protection on the whole
Sensitivity.
The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention.The technology of the industry
Personnel are it should be appreciated that the present invention is not limited to the above embodiments, and the above embodiments and description only describe this
The principle of invention, without departing from the spirit and scope of the present invention, various changes and improvements may be made to the invention, these changes
Change and improvement all fall within the protetion scope of the claimed invention.The claimed scope of the invention by appended claims and its
Equivalent thereof.
Claims (10)
1. a kind of join the series transformer longitudinal differential protecting equipment sentenced based on double differential module, it is characterised in that: including the first electric current
Mutual inductor, the second current transformer, third current transformer, the first discrimination module and the second discrimination module；
First current transformer and third current transformer are separately positioned on the both ends of series transformer primary side winding, respectively
Acquire the head end electric current and tail current of series transformer primary side winding；
One end of series transformer vice-side winding is arranged in second current transformer, acquisition series transformer vice-side winding
Electric current；
First current transformer, the second current transformer and the first discrimination module constitute the first differential module, and first differentiates
It is poor that the electric current of head end electric current and series transformer vice-side winding of the module based on collected series transformer primary side winding carries out
Dynamic protection calculates；
The third current transformer, the second current transformer and the second discrimination module constitute the second differential module, and second differentiates
It is poor that the electric current of tail current and series transformer vice-side winding of the module based on collected series transformer primary side winding carries out
Dynamic protection calculates；
When any of the first differential module and the second differential module meet the differential action condition of setting, series connection change is controlled
The longitudinal difference protection movement of depressor configuration.
2. a kind of series transformer longitudinal differential protecting equipment sentenced based on double differential module connection according to claim 1, special
Sign is: the head end electric current of the series transformer primary side winding is the secondary current of the first current transformer.
3. a kind of series transformer longitudinal differential protecting equipment sentenced based on double differential module connection according to claim 1, special
Sign is: the tail current of the series transformer primary side winding is the secondary current of third current transformer.
4. a kind of series transformer longitudinal differential protecting equipment sentenced based on double differential module connection according to claim 1, special
Sign is: the first discrimination module and the second discrimination module in first differential module and the second differential module using identical or
Person different difference stream and braking threshold computations formula.
5. a kind of join the series transformer longitudinal differential protection method sentenced based on double differential module characterized by comprising
(1) head end electric current of series transformer primary side winding, the tail current and string of series transformer primary side winding are acquired in real time
Join the electric current of transformer secondary winding；
(2) head end electric current and series transformer pair of first differential module based on collected series transformer primary side winding are utilized
The electric current real-time perfoming differential protection of side winding calculates；
(3) tail current and series transformer pair of second differential module based on collected series transformer primary side winding are utilized
The electric current real-time perfoming differential protection of side winding calculates；
(4) when any of the first differential module and the second differential module meet the differential action condition of setting, the string is controlled
Join the longitudinal difference protection movement of transformer configuration.
6. a kind of series transformer longitudinal differential protection method sentenced based on double differential module connection according to claim 5, special
Sign is: the step (1) specifically includes:
1.1 are respectively set the first current transformer and third current transformer at the both ends of series transformer primary side winding, respectively
Acquire the head end electric current of series transformer primary side winding and the tail current of series transformer primary side winding；
1.2 are arranged the second current transformer in one end of series transformer vice-side winding, acquisition series transformer vice-side winding
Electric current.
7. a kind of series transformer longitudinal differential protection method sentenced based on double differential module connection according to claim 6, special
Sign is: the first differential module described in the step (2) include the first connected current transformer, the second current transformer and
First discrimination module, head end electric current and series transformer of first discrimination module based on collected series transformer primary side winding
The electric current real-time perfoming differential protection of vice-side winding calculates；Second differential module includes connected third Current Mutual Inductance
Device, the second current transformer and the second discrimination module, the second discrimination module is based on collected series transformer primary side winding
The electric current real-time perfoming differential protection of tail current and series transformer vice-side winding calculates.
8. a kind of series transformer longitudinal differential protection method sentenced based on double differential module connection according to claim 6, special
Sign is: the head end electric current of the series transformer primary side winding is the secondary current of the first current transformer.
9. a kind of series transformer longitudinal differential protection method sentenced based on double differential module connection according to claim 6, special
Sign is: the tail current of the series transformer primary side winding is the secondary current of third current transformer.
10. a kind of series transformer longitudinal differential protection method sentenced based on double differential module connection according to claim 5 or 6,
It is characterized by: first differential module and the second differential module are using same or different difference stream and braking threshold computations
Formula.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710183487.5A CN108631265B (en) | 2017-03-24 | 2017-03-24 | It is a kind of that the series transformer longitudinal differential protecting equipment sentenced and method are joined based on double differential module |
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|---|---|---|---|
| CN201710183487.5A CN108631265B (en) | 2017-03-24 | 2017-03-24 | It is a kind of that the series transformer longitudinal differential protecting equipment sentenced and method are joined based on double differential module |
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| CN108631265A CN108631265A (en) | 2018-10-09 |
| CN108631265B true CN108631265B (en) | 2019-08-30 |
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|---|---|---|---|---|
| JPH07123582A (en) * | 1993-10-22 | 1995-05-12 | Hitachi Ltd | Protective unit for transformer |
| CN1137157A (en) * | 1995-02-06 | 1996-12-04 | 株式会社日立制作所 | Phase-shifting transformer and protection system of phase-shifting transformer |
| CN201203987Y (en) * | 2008-03-05 | 2009-03-04 | 李瑞生 | Experimental equipment for teaching power system automation and relay protection |
| CN103579999A (en) * | 2012-07-30 | 2014-02-12 | 国电南瑞科技股份有限公司 | High-sampling-rate method for sampling value differential protection of multi-section type self-adaption transformer |
| CN106356814A (en) * | 2016-09-07 | 2017-01-25 | 南京南瑞继保电气有限公司 | Series transformer winding overvoltage protection method based on voltage vector difference |
| WO2017115951A1 (en) * | 2015-12-30 | 2017-07-06 | 주식회사 효성 | Apparatus and method for controlling circuit breaker for static synchronous compensator |
-
2017
- 2017-03-24 CN CN201710183487.5A patent/CN108631265B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07123582A (en) * | 1993-10-22 | 1995-05-12 | Hitachi Ltd | Protective unit for transformer |
| CN1137157A (en) * | 1995-02-06 | 1996-12-04 | 株式会社日立制作所 | Phase-shifting transformer and protection system of phase-shifting transformer |
| CN201203987Y (en) * | 2008-03-05 | 2009-03-04 | 李瑞生 | Experimental equipment for teaching power system automation and relay protection |
| CN103579999A (en) * | 2012-07-30 | 2014-02-12 | 国电南瑞科技股份有限公司 | High-sampling-rate method for sampling value differential protection of multi-section type self-adaption transformer |
| WO2017115951A1 (en) * | 2015-12-30 | 2017-07-06 | 주식회사 효성 | Apparatus and method for controlling circuit breaker for static synchronous compensator |
| CN106356814A (en) * | 2016-09-07 | 2017-01-25 | 南京南瑞继保电气有限公司 | Series transformer winding overvoltage protection method based on voltage vector difference |
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| CN108631265A (en) | 2018-10-09 |
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