CN107294072A - A kind of optical fiber longitudinal differential protection method for being applied to 3/2 wiring TA saturations - Google Patents
A kind of optical fiber longitudinal differential protection method for being applied to 3/2 wiring TA saturations Download PDFInfo
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- CN107294072A CN107294072A CN201710573174.0A CN201710573174A CN107294072A CN 107294072 A CN107294072 A CN 107294072A CN 201710573174 A CN201710573174 A CN 201710573174A CN 107294072 A CN107294072 A CN 107294072A
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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
- H02H7/26—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured
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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
- H02H7/22—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 distribution gear, e.g. bus-bar systems; for switching devices
- H02H7/226—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 distribution gear, e.g. bus-bar systems; for switching devices for wires or cables, e.g. heating wires
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- Emergency Protection Circuit Devices (AREA)
Abstract
The invention discloses a kind of optical fiber longitudinal differential protection method for being applied to 3/2 wiring TA saturations, comprise the following steps：(1) configuration information of both sides protection device is transmitted by optical fiber, so as to obtain the corresponding outside primary connection form of both sides protection circuit；(2) both sides protection performs corresponding TA and differentiates scheme according to the primary connection mode of protected circuit；(3) according to the mode of connection of actual TA current direction and protected circuit, the corresponding stalling current of Auto-matching, it is ensured that the validity of stalling current.The preferably compatible existing conventional differential protection scheme of the present invention; can be on the premise of existing protection device system sampling frequency and channel information coded system not be changed; the mode of connection of adaptive protected circuit; and corresponding stalling current scheme can intelligently be switched according to TA saturated conditions, so that it is guaranteed that the correct operation of optical fiber longitudinal differential protection.
Description
Technical field
The present invention relates to technical field of relay protection, the vertical connection of especially a kind of optical fiber for being applied to 3/2 wiring TA saturations is poor
Dynamic guard method.
Background technology
3/2 wiring has the advantages that reliability height, operational flexibility are good, is widely used in 500kV transformer stations.It is a kind of
Typical 3/2 wiring is as shown in Figure 1.Transmission line of electricity under 3/2 wiring, generally using optical fiber current comparison pilot protection conduct
Main protection, Typical Disposition is 2M optical fiber transceiving equipment.
The requirement of real-time of protection device is limited by, the transmission capacity of optical fiber transceiving equipment is restricted.And in 3/2 wiring
Side form analog quantity is more (each three-phase current of TA1, TA2, altogether 6 magnitudes of current), adoptable if above-mentioned data are transmitted into offside
Method has；(1) sample frequency of protection device is reduced；(2) existing fiber communication code mode is changed.The former can reduce the magnitude of current
Computational accuracy (sample frequency is higher, and precision is higher), the latter can change the bottom-layer design of hardware and it also requires design is new
Mating optical transceiver.Therefore, widespread practice is to be transmitted to offside again after the two-way electric current of 3/2 connection side is synthesized, with
Reach the purpose for saving bandwidth.
But such scheme is used, there is the problem of TA saturated characteristics loss, differential protection possibility malfunction.Using Fig. 1, Fig. 2 as
Example, when external area error occurs for system and saturation occurs for TA2, waveform, which is presented, in its corresponding current Ia2 has the typical case such as angular interval TA
Saturated characteristic, is shown in Fig. 2 " this side I2 " waveforms；And the electric current after TA1 is synthesized with TA2 loses the typical characteristics of saturation, sees
Fig. 2 " this side interflow " waveform, the waveform can make the TA saturations criterion commonly used at present fail, and then may cause protection device not
Correct operation.
In addition, there is also the possibility of external area error malfunction for existing differential action criterion.Current conventional differential action
Logic is：
Wherein IdifRepresent difference current, IreRepresent stalling current, ImkFor action threshold, k is the differential system of differential protection
Number.
Difference current calculates formula
Stalling current calculation formula is
WhereinThe respectively corresponding secondary side current of TA1, TA2, TA3.
In the external area error shown in Fig. 1 and TA2 saturations, according to Kirchhoff's law, TA1, TA2, TA3 primary side current
Vector is 0, in the absence of difference stream；But due to TA2 saturations, cause its secondary side current to be unable to linear transform primary current, therefore produce
Raw difference stream.During due to TA2 saturations, less than normal, the I obtained according to equation (2) during the more normal progress of disease of its progress of disease electric currentdifActual flow direction
To be flowed out from dashed box shown in Fig. 1, withApproximate same-phase；Equation (2) is brought into equation (3), obtaining stalling current is
From equation (4) as can be seen that IreWithSize and change.WhenWhen, IreIt is approximately equal toSystem
Streaming current is larger, and difference current is smaller, the reliable locking of differential protection；With IdifWhen close, IreIt is similar to IdifIt is equal, according to
Differential action equation (1), differential protection may be acted, so as to lose the selectivity of relay protection.
In summary, under 3/2 mode of connection, if occurring TA saturations, conventional differential protection side caused by external area error
There is the defect of the possible malfunction of saturation criterion failure, differential protection in case.Protected therefore, it is necessary to improve existing optical fiber longitudinal differential
Shield scheme, it is ensured that in these cases, both sides protection device energy correct decision TA saturations, and reliable Blocking Differential Protection.
The content of the invention
The technical problems to be solved by the invention are that there is provided a kind of vertical connection of optical fiber for being applied to 3/2 wiring TA saturations is poor
Dynamic guard method, this method is compatible with existing conventional differential protection scheme, being capable of connecing according to protected circuit
Line mode, TA operating conditions, the corresponding stalling current scheme of intelligent Matching can be prevented effectively because external area error TA saturations cause
Differential malfunction, improve optical fiber longitudinal differential protection reliability.
Protected in order to solve the above technical problems, the present invention provides a kind of optical fiber longitudinal differential for being applied to 3/2 wiring TA saturations
Maintaining method, comprises the following steps：
(1) configuration information of both sides protection device is transmitted by optical fiber, so as to obtain the corresponding outside of both sides protection circuit
Primary connection form；
(2) both sides protection performs corresponding TA and differentiates scheme according to the primary connection mode of protected circuit；
(3) according to the mode of connection of actual TA current direction and protected circuit, the corresponding stalling current of Auto-matching,
Ensure the validity of stalling current.
It is preferred that, in step (1), primary connection form has 3/2 wiring or non-3/2 wiring, and both sides protection device is according to certainly
Body configuration information, obtains its corresponding external cabling form, and send connection type to offside with 1bit.
It is preferred that, in step (2), 3/2 connection side is sent simultaneously to offside closes electric current and each phase saturation differentiation result, non-3/
2 connection sides send this side three-phase current simultaneously to offside and each phase saturation differentiates result.
It is preferred that, in step (3), the Choice of stalling current during TA saturations is：
WhereinThe respectively corresponding secondary side current of TA1, TA2, TA3；According to equation (5), outside generating region
During failure, the electric current of TA1, TA2, TA3 three meet Kirchhoff's current law (KCL), and now maximum stalling current is the electricity flowed into
Flow vector subtracts outflow current vector, takes its modulus value；As broken down at F1 and during TA2 saturations,
The corresponding electric currents of TA2Modulus value during the more normal progress of disease diminishes, but to angle still withOn the contrary, therefore can select
Going out maximum stalling current isAccording to above-mentioned stalling current computational methods and Kirchhoff's current law (KCL), choose differential
Electric current stalling current coefficient of comparisons is 1.05~1.1.After such scheme, can in TA saturations caused by external area error,
Reliable Blocking Differential Protection relay；Meanwhile, when external area error turns troubles inside the sample space, it can quickly open differential protection relay
Device.
Beneficial effects of the present invention are：(1) selection of stalling current is more scientific, it can be ensured that in 3/2 wiring external area error
During caused TA saturations, differential protection is reliably failure to actuate, and when external area error turns troubles inside the sample space, it is poor even if occurring TA saturations
Dynamic protection still quickly can be exported correctly；(2) information code efficiency is high, is not changing the feelings of existing sample frequency and data encoding
Condition, it is only necessary to increase less transmission byte number, this side protection device can just obtain each phase TA saturation informations of offside；(3) certainly
The mode of connection of protected circuit is adapted to, corresponding stalling current scheme can be chosen automatically according to TA operating conditions.
Brief description of the drawings
Fig. 1 is 3/2 wiring schematic diagram of the invention.
Fig. 2 is the external area error TA of present invention saturation schematic diagram.
Fig. 3 is both sides differential protection schematic flow sheet of the invention.
Embodiment
A kind of optical fiber longitudinal differential protection method for being applied to 3/2 wiring TA saturations, comprises the following steps：
(1) configuration information of both sides protection device is transmitted by optical fiber, so as to obtain the corresponding outside of both sides protection circuit
Primary connection form；
(2) both sides protection performs corresponding TA and differentiates scheme according to the primary connection mode of protected circuit；
(3) according to the mode of connection of actual TA current direction and protected circuit, the corresponding stalling current of Auto-matching,
Ensure the validity of stalling current.
In step (1), primary connection form has 3/2 wiring or non-3/2 wiring, and both sides protection device matches somebody with somebody confidence according to itself
Breath, obtains its corresponding external cabling form, and send connection type to offside with 1bit.
In step (2), 3/2 connection side is sent simultaneously to offside closes electric current and each phase saturation differentiation result, non-3/2 connection side
This side three-phase current is sent simultaneously to offside and each phase saturation differentiates result.
In step (3), under TA saturated conditions, the selection of stalling current uses following scheme：
WhereinThe respectively corresponding secondary side current of TA1, TA2, TA3；Equation (5) possesses preferably general
Property, 3/2 side, non-3/2 side differential protection can be applied to simultaneously.Under two kinds of different modes of connection, equation (5) having differences place
Reason.It is explained respectively for 3/2 side, non-3/2 side separately below：
(1) 3/2 side tupe.According to equation (5), when occurring external area error, the electric current of TA1, TA2, TA3 three are
Kirchhoff's current law (KCL) is met, now maximum stalling current is that the current vector flowed into subtracts outflow current vector, is taken
Its modulus value；As Fig. 1 F1 at break down and during TA2 saturations, althoughIt is less than normal during the more normal progress of disease of modulus value, but to angle still withOn the contrary, event maximum stalling current is
In equation (6), IdifWithIn the opposite direction, thus Ire>Idif, i.e. stalling current is more than difference current, and 3/2 side is differential
Protection can reliable locking.
(2) non-3/2 side tupe.Non- 3/2 side protection device has 2 analoglike amounts：The conjunction electric current that offside is transmittedWith
And the electric current of itselfWhereinFor the vector of 2 road electric currents of the wiring of offside 3/2.In order to be applicable equation (5), orderWhen occurring F1 external area errors and the TA saturations shown in Fig. 1,WithSame phase,
According to equation (5), the stalling current that can obtain non-3/2 side is
According to equation (7), non-3/2 side difference current is equal with stalling current, can be by raising the k values in equation (1)
(span 1.05~1.1), it is ensured that difference current is less than (stalling current * k), so as to by Blocking Differential Protection.
To sum up shown, in TA saturations caused by external area error, equation (5) can be applied to 3/2 connection side, non-3/ simultaneously
2 connection sides, it can be ensured that differential protection is reliably failure to actuate, and when in Wai Zhuan areas of area, also can quickly open differential protection after
Electrical equipment.
As shown in figure 3, a kind of optical fiber longitudinal differential protection method for being applied to 3/2 wiring TA saturations, mainly by sending side,
Receiving side is completed jointly.For being protected for both sides, reciprocity status is in, while being used as sending side, receiving side.
Transmission, reception process are described respectively：
(1) sending side.Sending side obtains the corresponding external cabling form in this side according to the configuration information of protection device.When
When this side is 3/2 wiring, protection device generation three-phase combination electric current, and judge each phase TA saturation information；When this side is non-3/2 side
During wiring, protection device collection three-phase electricity flow valuve, and judge each phase TA saturation information.Sending side is obtained after the above results, is led to
Cross optical-fibre channel and above- mentioned information is sent to offside.
(2) receiving side.Receiving side by optical fiber interface obtain offside transmit information, information include offside connection type,
Current value, TA saturation informations etc..Receiving side can protect situation according to protection starting state and TA, start corresponding action logic.
In the case of protection starts, in the event of this side TA saturations or offside TA saturations, the differential versions for becoming stalling current are performed；If two
Side without TA saturations, then performs conventional differential versions.
Special instruction is needed, under TA saturated conditions caused by external area error, in order to reliably prevent differential protection malfunction,
The present invention is using the differential versions for becoming stalling current.The program is based on Kirchhoff's theorem, by choosing maximum system
Streaming current simultaneously raises braking threshold coefficient k so that difference current is less than (stalling current * k), so as to by Blocking Differential Protection.
In TA saturations, the selection of stalling current uses following scheme：
In order to adapt to the different wiring in both sides, classification processing is carried out by situation to equation (8), specifically：
During (1) 3/2 wiring,The respectively corresponding electric current in this side,For offside electric current；
(2) during non-3/2 side joint line,Electric current is closed for offside,For 0,For this side electric current.
The preferably compatible existing conventional differential protection scheme of the present invention, can not change existing protection device system
On the premise of sample frequency and channel information coded system, the mode of connection of adaptive protected circuit, and can be according to TA
Saturated conditions intelligently switches corresponding stalling current scheme, so that it is guaranteed that the correct operation of optical fiber longitudinal differential protection.
Although the present invention is illustrated and described with regard to preferred embodiment, it is understood by those skilled in the art that
Without departing from scope defined by the claims of the present invention, variations and modifications can be carried out to the present invention.
Claims (4)
1. a kind of optical fiber longitudinal differential protection method for being applied to 3/2 wiring TA saturations, it is characterised in that comprise the following steps：
(1) configuration information of both sides protection device is transmitted by optical fiber, so as to obtain the corresponding outside of both sides protection circuit once
Connection type；
(2) both sides protection performs corresponding TA and differentiates scheme according to the primary connection mode of protected circuit；
(3) according to the mode of connection of actual TA current direction and protected circuit, the corresponding stalling current of Auto-matching, it is ensured that
The validity of stalling current.
2. it is applied to the optical fiber longitudinal differential protection method of 3/2 wiring TA saturations as claimed in claim 1, it is characterised in that
In step (1), primary connection form has 3/2 wiring or non-3/2 wiring, and both sides protection device is obtained according to own configuration information
Its corresponding external cabling form, and send connection type to offside with 1bit.
3. it is applied to the optical fiber longitudinal differential protection method of 3/2 wiring TA saturations as claimed in claim 1, it is characterised in that
In step (2), 3/2 connection side is sent simultaneously to offside closes electric current and each phase saturation differentiation result, and non-3/2 connection side is same to offside
When send this side three-phase current and each phase saturation and differentiate result.
4. it is applied to the optical fiber longitudinal differential protection method of 3/2 wiring TA saturations as claimed in claim 1, it is characterised in that
In step (3), the Choice of stalling current during TA saturations is：
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WhereinThe respectively corresponding secondary side current of TA1, TA2, TA3；According to equation (5), occurring external area error
When, the electric current of TA1, TA2, TA3 three meet Kirchhoff's current law (KCL), now maximum stalling current be the electric current that flows into
Amount subtracts outflow current vector, takes its modulus value；As broken down at F1 and during TA2 saturations, the corresponding electric currents of TA2It is relatively normal to pass
Modulus value during change diminishes, but to angle still with On the contrary, therefore maximum stalling current can be selected beingAccording to upper
Stalling current computational methods and Kirchhoff's current law (KCL) are stated, it is 1.05~1.1 to choose difference current stalling current coefficient of comparisons；
, can be in TA saturations caused by external area error after such scheme, reliable Blocking Differential Protection relay；Meanwhile, in area
When outer failure turns troubles inside the sample space, differential protection relay can be quickly opened.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710573174.0A CN107294072B (en) | 2017-07-14 | 2017-07-14 | A kind of optical fiber longitudinal differential protection method suitable for 3/2 wiring TA saturation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710573174.0A CN107294072B (en) | 2017-07-14 | 2017-07-14 | A kind of optical fiber longitudinal differential protection method suitable for 3/2 wiring TA saturation |
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| CN107294072A true CN107294072A (en) | 2017-10-24 |
| CN107294072B CN107294072B (en) | 2019-01-01 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109283421A (en) * | 2018-10-16 | 2019-01-29 | 中铁电气化（武汉）设计研究院有限公司 | A kind of rail traction substation low-voltage is powered detection test method and device |
| CN113964799A (en) * | 2020-07-20 | 2022-01-21 | 南京南瑞继保电气有限公司 | Method and device for preventing differential protection unwanted operation at two ends of T area |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104242262A (en) * | 2014-08-28 | 2014-12-24 | 山东大学 | Rapid bus protection method based on fault component mean value product |
| CN105429111A (en) * | 2015-12-07 | 2016-03-23 | 许继集团有限公司 | Method for preventing differential protection maloperation of optical fiber caused by single CT saturation of 3/2 connection |
-
2017
- 2017-07-14 CN CN201710573174.0A patent/CN107294072B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104242262A (en) * | 2014-08-28 | 2014-12-24 | 山东大学 | Rapid bus protection method based on fault component mean value product |
| CN105429111A (en) * | 2015-12-07 | 2016-03-23 | 许继集团有限公司 | Method for preventing differential protection maloperation of optical fiber caused by single CT saturation of 3/2 connection |
Non-Patent Citations (1)
| Title |
|---|
| 兰金波: "基于双光纤通道的超高压线路差动保护", 《万方学位论文全文库》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109283421A (en) * | 2018-10-16 | 2019-01-29 | 中铁电气化（武汉）设计研究院有限公司 | A kind of rail traction substation low-voltage is powered detection test method and device |
| CN109283421B (en) * | 2018-10-16 | 2024-02-09 | 中铁电气化（武汉）设计研究院有限公司 | Low-voltage power-on detection test method and device for railway traction substation |
| CN113964799A (en) * | 2020-07-20 | 2022-01-21 | 南京南瑞继保电气有限公司 | Method and device for preventing differential protection unwanted operation at two ends of T area |
| CN113964799B (en) * | 2020-07-20 | 2024-01-02 | 南京南瑞继保电气有限公司 | Method and device for preventing differential protection misoperation at two ends of T region |
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