CN108683161A - A kind of differential back-up protection method applied to intelligent distribution network - Google Patents
A kind of differential back-up protection method applied to intelligent distribution network Download PDFInfo
- Publication number
- CN108683161A CN108683161A CN201810551482.8A CN201810551482A CN108683161A CN 108683161 A CN108683161 A CN 108683161A CN 201810551482 A CN201810551482 A CN 201810551482A CN 108683161 A CN108683161 A CN 108683161A
- Authority
- CN
- China
- Prior art keywords
- main
- differential
- neighbours
- protection
- differential ring
- Prior art date
- 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
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
- H02H7/26—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
-
- 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
- H02H7/261—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 involving signal transmission between at least two stations
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The invention discloses a kind of differential back-up protection methods applied to intelligent distribution network, include the following steps：Step 1：Communication check and communication failure processing；Step 2：CT is detected and CT troubleshootings；Step 3：Main protection；Step 4：Back-up protection.Distributed differential protection is applied to back-up protection by the present invention, and main protection and back-up protection are combined.When secondary side failure; when primary side failure is happened in secondary side faulty section; main protection is failed; back-up protection can correctly trip, and fault coverage is only expanded to upper level, the back-up protection time close to the main protection time; protect speed fast; and primary side failure, when being happened at outside secondary side faulty section, main protection correctly acts, back-up protection not malfunction；In the case of tripping, this mode becomes active back-up protection mode, the cover information requirements standby cover sent out in the main differential ring that the neighbours to be different from neighbours and neighbours form；More rapidly than traditional cover mode.
Description
Technical field
The present invention relates to field of power distribution, more particularly to a kind of differential back-up protection method applied to intelligent distribution network.
Background technology
With the development of the social economy, user side is higher and higher to power supply reliability requirement, to provide the electricity of safe and high quality
Power, application of the electron electric power technology in intelligent grid, distributed power grid to Power System Planning, power quality, relay protection,
Reliability etc. all plays positive effect.For the distribution system containing distributed generation resource, due to the randomness of its power supply processing,
The customization that conventional current is protected is caused to be difficult to determine.In traditional distribution protection system, containing current quick, electricity of prescribing a time limit
It flows fast tripping protection and definites time-lag the stage current protection of overcurrent protection, but as distributed power supply system accesses, there is protection
The problems such as dead zone, parameter tuning and sensitivity, the protection for feed line based on automatic circuit mode lead to the power failure of wide scope of power outage, length
Time and and that there are back-up protection functions is insufficient.System is protected based on the feeder automation of communication is concentrated, using centralized control as core
The feeder automation of the heart protects system, based on the wide area observing and controlling and protection system for synchronizing vectorial measurement unit, can obtain power distribution network
Global information simultaneously can be coordinated and be optimized to whole system.However, this based on concentration communication and central controlled protection side
Formula has information transmission congestion and computationally intensive, the especially sound of its back-up protection when power distribution network breaks down
Answer speed slow.
The distributed differential protection occurred in recent years, using quick communication network and based on Kirchhoff's current law (KCL)
Differential Protection Theory fast response time and is not influenced using multiterminal electrical quantity come failure judgement by system concussion, has excellent choosing
The advantages that phase ability, uses so far as main protection always.Regrettably, because communicate upper each communication node only with its neighbor node
Communication, does not have the communication port of back-up protection, and practical application is never obtained in back-up protection field.
Invention content
In order to solve the above technical problem, the present invention provides a kind of algorithms simple, safe and reliable to be applied to intelligent power distribution
The differential back-up protection method of net.
Technical proposal that the invention solves the above-mentioned problems is：A kind of differential back-up protection side applied to intelligent distribution network
Method includes the following steps：
1) each intelligent FTU periodically carries out communication frame detection with its neighbours' intelligent FTU, enters step
2)；
2) judge whether communication failure occurs between itself intelligent FTU and neighbours' intelligent FTU, be then to enter step
It is rapid 3), otherwise go to step 6)；
3) judge that whether all communication links of itself intelligent FTU break down, be to go to step 5)；Otherwise it means
It is that communication failure occurs for neighbours' intelligent FTU, and is entered step 4)；
4) mark and neighboring communication link failure, locking include the main protection of failing communication link, and report main website, turn step
It is rapid 6)；
5) it opens three section protection and reports main website, then go to step 20)；
6) each intelligent FTU periodically carries out CT burn out detection, enters step 7)；
7) judge whether each intelligent FTU CT breaks, be to enter step 8), otherwise go to step 9)；
8) circuit breaker lock of CT broken strings, includes the main protection locking of the breaker of CT broken strings, and reports main website, then turns
Step 20)；
9) judge whether itself intelligent FTU meets protection entry condition, be, enter step 10), otherwise go to step
18)；
10) it itself intelligent FTU and neighbours' intelligent FTU exchanging electric current information and carries out leading differential calculating, with
Neighbours' intelligent FTU exchanging electric current information of all neighbours simultaneously carries out the differential calculating of standby, subsequently into step 11)；
11) judge in main differential ring whether failure, be to go to step 15)；Otherwise it enters step 12)；
12) judge standby differential ring whether failure, be to enter step 13), otherwise go to step 18)；
13) judge in standby differential ring whether CT failures or communication failure, be to go to step 15), otherwise enter step
14)；
14) judge in the main differential ring being made of neighbours' breaker of neighbours' breaker and neighbours in standby differential ring whether
There are breaker trippings, are, enter step 15), otherwise go to step 18)；
15) 16) output circuit breaker trip instruction, enters step；
16) judge itself breaker whether tripping, be to enter step 17), otherwise go to step 20)；
17) it sends neighbours' cover information and reports main website, go to step 20)；
18) judge whether to receive neighbours' cover information and do not export trip command, be to enter step 19), otherwise turn to walk
It is rapid 20)；
19) 20) output circuit breaker trip instruction, enters step；
20) EP (end of program).
Above application judges itself Intelligent feeder line in the differential back-up protection method of intelligent distribution network, the step 2)
The criterion of generation communication failure is between terminal and neighbours' intelligent FTU：Itself intelligent FTU repeatedly sends communication check
Frame gives neighbours' intelligent FTU, but does not receive any return information；
In the step 3), judge that the criterion that all communication links of itself intelligent FTU break down is：Itself intelligence
There are communication link fails with all neighbours' intelligent FTUs in energy line feed terminals.
Above application judges the criterion of CT broken strings in the differential back-up protection method of intelligent distribution network, the step 7)
For：Meet following formula
Wherein：For both sides zero-sequence current；For this side electric current of spill current maximum phase, acquisition pattern
For：First calculate separately A, B, C three-phase spill currentJudgement obtains maximum phase spill current
Phase remembers that the spill current of this phase is this side electric current of spill current maximum phaseIMKIt is equal to 6% for preset threshold value
In, InFor rated current；IWIFor no current threshold value.
Above application includes the open circuit of CT broken strings in the differential back-up protection method of intelligent distribution network, the step 8)
The main protection of device is latched：The master of the intelligent FTU neighbours intelligent FTU composition all with it of CT broken strings is differential
Protection blocking, how many neighbours of the intelligent FTU of CT broken strings are with regard to how many differential ring and main differential protection.
Above application protects opening for entry condition in the differential back-up protection method of intelligent distribution network, the step 9)
Dynamic criterion is:Initiating element includes current change quantity initiating element, zero sequence overcurrent initiating element, phase overcurrent initiating element, voltage
Auxiliary starter element, as long as one of element movement, then it is assumed that initiating element starts, and meets protection entry condition.
Above application is in the differential back-up protection method of intelligent distribution network, the step 11), the definition of main differential ring
For：For the structure of ring main unit form, including two differential rings, i.e. busbar itself differential ring and adjacent ring main unit offside forms
Differential ring；
Failure criterion in main differential ring is：The mathematic(al) representation for meeting action logic is：Regulation is with mother
It is positive direction that line, which flows to protected circuit, and the electric current for flowing through two terminal protecting circuit of circuit isWith both ends current vector and
As differential relay action current Id, using both ends current vector difference as differential relay stalling current Ir, i.e.,IqdFor starting current, KrFor restraint coefficient.
Above application is in the differential back-up protection method of intelligent distribution network, the step 12), the definition of standby differential ring
For：The arbitrary main differential ring of itself breaker and the main differential ring comprising its neighbours' breaker but not comprising its own breaker
Boundary is as a standby differential ring；The number of the standby differential ring of itself breaker is equal to the neighbours that it is not boundary switch
Number；
In the step 12), the failure criterion in standby differential ring is：The mathematic(al) representation for meeting action logic is：
Above application is in the differential back-up protection method of intelligent distribution network, the step 13), communication in standby differential ring
Or the criterion of CT failures is：Judge that main protection all CT breakage lock devices or the standby of two main differential rings in standby differential ring are poor
The main protection of a main differential ring in rotating ring all communicates locking.
Above application judges that neighbours' breaker is refused in the differential back-up protection method of intelligent distribution network, the step 14)
Dynamic criterion is：The judgement of standby differential ring is out of order, and itself main differential ring in standby differential ring cannot judge to be out of order, but
The main differential ring of neighbours' breaker and neighbours' breaker of neighbours composition can judge to be out of order, through delay Δ T after a period of time
=Tp+Tpb, TpFor circuit breaker trip maximum time, TpbFor time margin, overcurrent condition still meets, then judges that standby is differential
The breaker tripping that each main differential ring has a common boundary in ring.
Above application judges that itself breaker is refused in the differential back-up protection method of intelligent distribution network, the step 16)
Dynamic criterion is：Breaker where intelligent FTU in main differential ring outputs trip command, through prolonging after a period of time
When Δ T=Tp+Tpb, TpFor circuit breaker trip maximum time, TpbFor time margin, the circuit breaker trip non-set of information in place is sentenced
Break and itself breaker tripping.
The beneficial effects of the present invention are：Distributed differential protection is applied to back-up protection by the present invention, compared to
Main protection before, the standby in more standby differential rings calculate.As secondary side failure (CT breaks and communication failure), once
When side failure is happened in secondary side faulty section, main protection failure, back-up protection can correctly trip, only be expanded to fault coverage
Upper level, the back-up protection time close to main protection time protect speed block, and primary side failure is happened at secondary side failure
When outside area, main protection correctly acts, back-up protection not malfunction；In the case of tripping, this mode becomes active back-up protection mode,
The cover information requirements standby cover sent out in the main differential ring that neighbours to be different from neighbours and neighbours form；Than traditional cover
Mode is more rapidly.
Description of the drawings
Fig. 1 is the particular flow sheet of the present invention.
Fig. 2 is main differential ring and standby differential ring schematic diagram.
Fig. 3 is standby differential ring definition figure.
Specific implementation mode
The present invention is further illustrated with reference to the accompanying drawings and examples.
As shown in Figure 1, a kind of differential back-up protection method applied to intelligent distribution network, includes the following steps：Step 1：
Communication check and communication failure processing；Step 2：CT is detected and CT troubleshootings；Step 3：Main protection；Step 4：Standby is protected
Shield.The specific steps are：
1) each intelligent FTU (abbreviation terminal) periodically carries out communication frame detection with its neighbor terminal, into step
It is rapid 2).
2) judge whether communication failure occurs between own terminal and neighbor terminal, be to enter step 3), otherwise go to step
6)。
Judge that the criterion that communication failure occurs between own terminal and neighbor terminal is：Own terminal repeatedly sends communication check
Frame does not receive any return information to neighbor terminal.
3) judge that whether all communication links of own terminal break down, be to go to step 5)；Otherwise neighbours are meant to be
Communication failure occurs for terminal, enters step 4).
Judge that the criterion that all communication links of own terminal break down is：Own terminal exists with all neighbor terminals
Communication link fails.
4) mark and neighboring communication link failure, locking include the main protection of failing communication link, and report main website, if
There are multiple communication link fails, then need to be latched multiple main protections, go to step 6).
5) it opens three section protection and reports main website, then go to step 20).
6) CT burn out detection is carried out to each terminal periodic, entered step 7).
7) judge whether each terminal CT breaks, be to enter step 8), otherwise go to step 9).
Judge that the criterion of CT broken strings is：Meet following formula
Wherein：For both sides zero-sequence current；For this side electric current of spill current maximum phase, acquisition pattern
For：First calculate separately A, B, C three-phase spill currentJudgement obtains maximum phase spill current
Phase remembers that the spill current of this phase is this side electric current of spill current maximum phaseIMKIt is equal to 6% for preset threshold value
In, InFor rated current；IWIFor no current threshold value.
8) circuit breaker lock of CT broken strings, includes the main protection locking of the breaker of CT broken strings, and reports main website, then turns
Step 20).
Including the main protection locking of the breaker of CT broken strings refers to：The master of the terminal neighbours composition all with it of CT broken strings
Differential protection is latched, how many neighbours are with regard to how many differential ring and main differential protection for the terminal of CT broken strings.Such as：Such as Fig. 2
Shown in, CT broken strings occur for RMU1-S2, then the equal main protections of main differential ring PDR1 and PDR2 are latched.
9) judge whether own terminal meets protection entry condition, be, enter step 10), otherwise go to step 18).
The start-up criterion of main (or standby) protection entry condition is:Initiating element includes mainly 4 parts：Current change quantity
Initiating element, zero sequence overcurrent initiating element, phase overcurrent initiating element, voltage auxiliary starter element, as long as one of element is dynamic
Make, then it is assumed that initiating element starts, and meets protection entry condition.Phase overcurrent initiating element, voltage is taken to assist under normal conditions
Dynamic element.
10) it own terminal and neighbor terminal exchanging electric current information and carries out leading differential calculating, it is whole with the neighbours of all neighbours
End exchanging electric current information simultaneously carries out the differential calculating of standby, subsequently into step 11)；
11) judge in main differential ring whether failure, be to go to step 15)；Otherwise it enters step 12).
The definition of main differential ring is：For the structure of ring main unit form, only include two differential rings under normal conditions, i.e., it is female
Line itself differential ring, the differential ring with adjacent ring main unit offside composition.For example, shown in Fig. 2, for RMU2-S1, there is busbar certainly
Body differential ring PDR3, the main differential ring PDR2 with adjacent ring main unit offside composition.
Failure criterion in main differential ring is：The mathematic(al) representation for meeting action logic is：Regulation is with busbar
It is positive direction to flow to protected circuit, and the electric current for flowing through two terminal protecting circuit of circuit isWith both ends current vector and work
For differential relay action current Id, using both ends current vector difference as differential relay stalling current Ir, i.e.,
IqdFor starting current, KrFor restraint coefficient.
12) judge standby differential ring whether failure, be to enter step 13), otherwise go to step 18).
The definition of standby differential ring is：The arbitrary main differential ring of itself breaker with comprising its neighbours' breaker but do not include
The boundary of the main differential ring of its own breaker is as a standby differential ring.Such as：As shown in figure 3, RMU2-S1 have 4 not
The neighbours (RMU1-S2, RMU2-S2, RMU2-S3, RMU2-S4) of boundary switch, then RMU2-S1 has 4 standby differential rings, point
It is not BDR1, BDR2, BDR3, BDR4.It (includes RMU1-S1, RMU1- that BDR1 is made of the boundary of main differential ring PDR2 and PDR1
Tri- breakers of S2, RMU1-S3)；BDR2 be made of the boundary of main differential ring PDR3 and PDR6 (comprising RMU2-S2, RMU2-S3,
Tetra- breakers of RMU2-S4, RMU5-S1)；BDR3 be made of the boundary of main differential ring PDR3 and PDR4 (comprising RMU2-S2,
Tetra- breakers of RMU2-S3, RMU2-S4, RMU4-S1)；BDR4 is made of the boundary of main differential ring PDR3 and PDR5
Tetra- breakers of RMU2-S2, RMU2-S3, RMU2-S4, RMU3-S4).
The number of the standby differential ring of itself breaker be equal to its be not boundary switch neighbours number.Such as：Such as Fig. 3
Shown, RMU5-S1 has 4 neighbours, but is boundary switch there are one neighbours RMU5-S3, so only there are three standby differential rings.
Failure criterion in standby differential ring is：The mathematic(al) representation for meeting action logic is：
13) judge in standby differential ring whether CT failures or communication failure, be to go to step 15), otherwise enter step
14)。
The criterion of communication or CT failures is in standby differential ring：(have determined that before program-judgement of standby differential ring has
Failure, itself main differential ring fault-free in standby differential ring or main protection locking) judge two main differences in standby differential ring
(the two equal set of main differential ring CT breakage lock device marks, it is meant that two main differential rings of the main protection of rotating ring all CT breakage lock devices
Crosspoint CT broken strings) or the main protection of a main differential ring in standby differential ring all communicate locking (two main differential rings lead to
Believe the equal set of failure locking mark, it is meant that the crosspoint communication failure of two main differential rings).
Such as (1)：In Fig. 2, failure is happened at the CT broken strings of F1 and RMU1-S2 (CT broken strings are located at fault point upstream).Afterwards
Standby differential ring BDR1 can judge to be out of order, and main differential ring PDR1 and PDR2 main protections have been latched and cannot judge to be out of order, satisfaction
Criterion, BDR1 (RMU1-S1, RMU1-S3 and RMU2-S1) standby output tripping.
And standby differential ring BDR0 can also judge to be out of order because the CT of RMU1-S2 breaks, but PDR0 main protections are judged
Fault-free, main differential ring PDR1 main protections, which have been latched, cannot judge to be out of order.Two main differences in standby differential ring cannot be met
The main protection of rotating ring all CT breakage lock devices (the two equal set of main differential ring CT breakage lock device marks) condition, therefore standby differential ring
BDR0 (CB1, RMU1-S1, RMU1-S3) will not malfunction tripping.
And standby differential ring BDR2 is in two kinds of situation, (i) both end power supplying：(similarly above-mentioned standby differential ring BDR0), standby
Differential ring BDR2 is because the CT broken strings of RMU1-S2 can also judge to be out of order, but fault-free, main differential ring are judged in PDR3 main protections
PDR2 main protections, which have been latched, cannot judge to be out of order.Main protection all CT of two main differential rings in standby differential ring cannot be met
Breakage lock device (the two equal set of main differential ring CT breakage lock device marks) condition, therefore standby differential ring BDR2 (RMU2-S1,
RMU2-S2, RMU2-S3) it will not malfunction tripping.(ii) single-ended power：Standby differential ring BDR2 cannot because of the CT broken strings of RMU1-S2
Judgement is out of order.The judgement of standby differential ring cannot be met to be out of order this condition, therefore standby differential ring BDR2 (RMU2-S1,
RMU2-S2, RMU2-S3) it will not malfunction tripping.
Such as (2)：In Fig. 2, failure is happened at the CT broken strings of F1 and RMU2-S1 (CT broken strings are located at trouble point downstream).Afterwards
Standby differential ring BDR2 can judge to be out of order, and main differential ring PDR2 and PDR3 main protections have been latched and cannot judge to be out of order, satisfaction
Criterion BDR2 (RMU1-S2, RMU2-S2, RMU2-S3) standby output tripping.Similarly, BDR1 and BDR3 is unsatisfactory for criterion, no
It can malfunction tripping.
Such as (3)：In Fig. 2, failure is happened at the CT broken strings of F1 and RMU2-S2 (CT broken strings are located at outside fault point).Main difference
Rotating ring PDR2 judgements are out of order, normal to trip.And main differential ring PDR3 and PDR4 have been latched not malfunction, similarly standby differential ring
BDR1, BDR2, BDR3 and BDR4 are unsatisfactory for criterion, will not malfunction.
Such as (4)：In Fig. 2, failure is happened at F1 and RMU1-S2 and RMU2-S1 communication link fails, it is assumed that the communication chain
Road failure (is located in physical fault area, communication failure node is located on fault point caused by RMU1-S2 nodes are communication failure
Trip).Standby differential ring BDR1 can judge to be out of order, main differential ring PDR1 and PDR2 main protections because communication failure has been latched cannot
Judgement is out of order, and BDR1 (RMU1-S1, RMU1-S3 and RMU2-S1) meets criterion, standby output tripping.
And standby differential ring BDR0 is out of order because that cannot judge, is unsatisfactory for criterion, therefore standby differential ring BDR0 is not
It can malfunction tripping.Standby differential ring BDR2 cannot judge to be out of order, and fault-free, main differential ring PDR2 are judged in PDR3 main protections
Main protection, which has been latched, cannot judge to be out of order.Criterion cannot be met, therefore standby differential ring BDR2 will not malfunction.
Such as (5)：In Fig. 2, failure is happened at F1 and RMU1-S2 and RMU2-S1 communication link fails, it is assumed that the communication chain
Road failure is that RMU2-S1 nodes are caused by communication failure (in faulty section, communication failure node is located at trouble point downstream).
Standby differential ring BDR2 can judge to be out of order, and main differential ring PDR2 and PDR3 main protections cannot judge because communication failure has been latched
It is out of order, BDR2 (RMU1-S2, RMU2-S2 and RMU2-S3) meets criterion, standby output tripping.Similarly BDR1 and BDR3 is discontented
Sufficient criterion, will not malfunction.
Such as (6)：In Fig. 2, failure is happened at the node communication failure of F1 and RMU2-S2, and (communication link fails are located at object
It manages outside fault point).Main differential ring PDR2 judgements are out of order, normal to trip.And main differential ring PDR3 and PDR4 has been latched not malfunction,
BDR1, BDR2, BDR3 and BDR4 are unsatisfactory for criterion, will not malfunction.
Therefore, as secondary side failure (CT breaks and communication failure), primary side failure is happened in secondary side faulty section
When, main protection failure, back-up protection can correctly trip, fault coverage is only expanded to upper level and the back-up protection time approaches
It is supper-fast in the main protection time.And primary side failure, when being happened at outside secondary side faulty section, main protection correctly acts, standby is protected
Protect not malfunction.
14) judge in the main differential ring being made of neighbours' breaker of neighbours' breaker and neighbours in standby differential ring whether
There are breaker trippings, are, enter step 15), otherwise go to step 18).
Judge that the criterion of neighbours' breaker tripping is：The judgement of standby differential ring is out of order, and itself in standby differential ring
Main differential ring cannot judge to be out of order, but the main differential ring of the neighbours of neighbours and neighbours composition can judge to be out of order, by one section
The delay Δ T=T of timep+Tpb, TpFor circuit breaker trip maximum time, TpbFor time margin, overcurrent condition still meets, then
Judge the breaker tripping that each main differential ring has a common boundary in standby differential ring.This mode becomes active back-up protection mode, with
It is different from the cover information requirements standby cover sent out in the main differential ring of neighbours' composition of neighbours and neighbours；Therefore it is mended than tradition
Position mode is more rapidly.
Such as (7)：In Fig. 2, failure is happened at the tripping of F1 and RMU1-S2, and (breaker of tripping is located on fault point
Trip), main differential ring PDR2 can judge to be out of order, and the standby differential ring BDR1 judgements of terminal are out of order in RMU1, and standby is differential
Itself main differential ring PDR1 in ring cannot judge to be out of order, and the main differential ring PDR2 of neighbours' composition of neighbours and neighbours can judge
It is out of order.Through delay Δ T=T after a period of timep+TpbOvercurrent condition still meets, and judges main in standby differential ring BDR1
The breaker tripping that differential ring PDR2 and PDR1 have a common boundary.
15) 16) output circuit breaker trip instruction, enters step.
16) judge itself breaker whether tripping, be to enter step 17), otherwise go to step 20).
Judge that the criterion of itself breaker tripping is：Breaker where terminal in main differential ring outputs trip command,
Through delay Δ T=T after a period of timep+Tpb(TpFor circuit breaker trip maximum time, TpbFor time margin), circuit breaker trip
Itself breaker tripping is judged in the non-set of information in place.
Such as (8)：In Fig. 2, failure is happened at the tripping of F1 and RMU2-S1, and (breaker of tripping is located under fault point
Trip), main differential ring PDR2 can judge to be out of order, and the standby differential ring BDR2 judgements of terminal are out of order in RMU2, and standby is differential
Itself main differential ring PDR3 in ring cannot judge to be out of order, and the master of neighbours' breaker composition of neighbours' breaker and neighbours is differential
Ring PDR2 can judge to be out of order.Through delay Δ T=T after a period of timep+Tpb(TpFor circuit breaker trip maximum time, TpbFor when
Between surplus), overcurrent condition has been unsatisfactory for, and cannot judge that main differential ring PDR2 and PDR1 have a common boundary in standby differential ring BDR1
Breaker tripping.It is specifically intended that the criterion has limitation：When single-ended power, rear Preparation Method cannot be to fault down stream
Breaker tripping carries out standby tripping, can only use and differentiate that main differential ring tripping carries out standby tripping using cover information.
17) it sends neighbours' cover information and reports main website, go to step 20).
18) judge whether to receive neighbours' cover information and do not export trip command, be to enter step 19), otherwise turn to walk
It is rapid 20).
It receives cover information and does not export trip command criterion：1) cover information is received, 2) trip command is not exported.
Explanation：2) it refers to excluding step 14) and 15) not export trip command, so if tripping is happened on faulty section
Trip, the active tripping of this standby, after just receive cover information.And refer in particular to, tripping is happened at faulty section downstream and non-spoke
Emitting structure without DG, this be standby cannot pick out neighbours whether tripping, need its own to pick out breaker tripping and exclude step
16) and 17).Therefore criterion：1) receive cover information, 2) not exporting trip command refers in particular to the latter.
19) 20) output circuit breaker trip instruction, enters step.
20) EP (end of program).
Claims (10)
1. a kind of differential back-up protection method applied to intelligent distribution network includes the following steps：
1) each intelligent FTU periodically carries out communication frame detection with its neighbours' intelligent FTU, enters step 2)；
2) judge whether communication failure occurs between itself intelligent FTU and neighbours' intelligent FTU, be to enter step
3) it, otherwise goes to step 6)；
3) judge that whether all communication links of itself intelligent FTU break down, be to go to step 5)；Otherwise it is meant to be
Communication failure occurs for neighbours' intelligent FTU, enters step 4)；
4) mark and neighboring communication link failure, locking include the main protection of failing communication link, and report main website, go to step
6)；
5) it opens three section protection and reports main website, then go to step 20)；
6) each intelligent FTU periodically carries out CT burn out detection, enters step 7)；
7) judge whether each intelligent FTU CT breaks, be to enter step 8), otherwise go to step 9)；
8) circuit breaker lock of CT broken strings, includes the main protection locking of the breaker of CT broken strings, and reports main website, then goes to step
20)；
9) judge whether itself intelligent FTU meets protection entry condition, be, enter step 10), otherwise go to step 18)；
10) it itself intelligent FTU and neighbours' intelligent FTU exchanging electric current information and carries out leading differential calculating, and it is all
Neighbours' intelligent FTU exchanging electric current information of neighbours simultaneously carries out the differential calculating of standby, subsequently into step 11)；
11) judge in main differential ring whether failure, be to go to step 15)；Otherwise it enters step 12)；
12) judge standby differential ring whether failure, be to enter step 13), otherwise go to step 18)；
13) judge in standby differential ring whether CT failures or communication failure, be to go to step 15), otherwise enter step 14)；
14) judge to whether there is in the main differential ring being made of neighbours' breaker of neighbours' breaker and neighbours in standby differential ring
Breaker tripping is to enter step 15), otherwise goes to step 18)；
15) 16) output circuit breaker trip instruction, enters step；
16) judge itself breaker whether tripping, be to enter step 17), otherwise go to step 20)；
17) it sends neighbours' cover information and reports main website, go to step 20)；
18) judge whether to receive neighbours' cover information and do not export trip command, be to enter step 19), otherwise go to step
20)；
19) 20) output circuit breaker trip instruction, enters step；
20) EP (end of program).
2. the differential back-up protection method according to claim 1 applied to intelligent distribution network, which is characterized in that the step
It is rapid 2) in, judge between itself intelligent FTU and neighbours' intelligent FTU occur communication failure criterion be：Itself intelligence
Line feed terminals repeatedly send communication check frame and give neighbours' intelligent FTU, but do not receive any return information；
In the step 3), judge that the criterion that all communication links of itself intelligent FTU break down is：Itself is intelligently presented
There are communication link fails with all neighbours' intelligent FTUs in line terminal.
3. the differential back-up protection method according to claim 1 applied to intelligent distribution network, which is characterized in that the step
It is rapid 7) in, judge CT broken string criterion be：Meet following formula
Wherein：For both sides zero-sequence current；For this side electric current of spill current maximum phase, acquisition pattern is：First
Calculate separately A, B, C three-phase spill currentJudgement obtains the phase of maximum phase spill current, remembers
The spill current of this phase is this side electric current of spill current maximum phaseIMKIt is equal to 6%I for preset threshold valuen, InFor
Rated current；IWIFor no current threshold value.
4. the differential back-up protection method according to claim 1 applied to intelligent distribution network, which is characterized in that the step
It is rapid 8) in, including CT broken string breaker main protection locking refer to：The intelligent FTU neighbours all with it of CT broken strings
The main differential protection locking of intelligent FTU composition, how many neighbours of intelligent FTU of CT broken strings are with regard to how many difference
Rotating ring and main differential protection.
5. the differential back-up protection method according to claim 1 applied to intelligent distribution network, which is characterized in that the step
It is rapid 9) in, protect the start-up criterion of entry condition to be:Initiating element includes current change quantity initiating element, zero sequence overcurrent starting member
Part, phase overcurrent initiating element, voltage auxiliary starter element, as long as one of element movement, then it is assumed that initiating element starts, full
Foot protection entry condition.
6. the differential back-up protection method according to claim 1 applied to intelligent distribution network, which is characterized in that the step
It is rapid 11) in, the definition of main differential ring is：For the structure of ring main unit form, including two differential rings, i.e. busbar itself is differential
Ring, the differential ring with adjacent ring main unit offside composition；
Failure criterion in main differential ring is：The mathematic(al) representation for meeting action logic is：Regulation is flowed to busbar
Protected circuit is positive direction, and the electric current for flowing through two terminal protecting circuit of circuit isUsing both ends current vector and as difference
Motor type relay action current Id, using both ends current vector difference as differential relay stalling current Ir, i.e.,IqdFor
Starting current, KrFor restraint coefficient.
7. the differential back-up protection method according to claim 6 applied to intelligent distribution network, which is characterized in that the step
It is rapid 12) in, the definition of standby differential ring is：The arbitrary main differential ring of itself breaker with comprising its neighbours' breaker but do not include
The boundary of the main differential ring of its own breaker is as a standby differential ring；The number etc. of the standby differential ring of itself breaker
In its be not the number of the neighbours of boundary switch；
In the step 12), the failure criterion in standby differential ring is：The mathematic(al) representation for meeting action logic is：
8. the differential back-up protection method according to claim 1 applied to intelligent distribution network, which is characterized in that the step
It is rapid 13) in, the criterion of communication or CT failures is in standby differential ring：Judge the main guarantor of two main differential rings in standby differential ring
The main protection of a main differential ring in shield all CT breakage lock devices or standby differential ring all communicates locking.
9. the differential back-up protection method according to claim 1 applied to intelligent distribution network, which is characterized in that the step
It is rapid 14) in, judge that the criterion of neighbours' breaker tripping is：The judgement of standby differential ring is out of order, and itself in standby differential ring
Main differential ring cannot judge to be out of order, but the main differential ring of neighbours' breaker and neighbours' breaker of neighbours composition can judge event
Barrier, through delay Δ T=T after a period of timep+Tpb, TpFor circuit breaker trip maximum time, TpbFor time margin, overcurrent condition
Still meet, then judges the breaker tripping that each main differential ring has a common boundary in standby differential ring.
10. the differential back-up protection method according to claim 1 applied to intelligent distribution network, which is characterized in that described
In step 16), judge that the criterion of itself breaker tripping is：Breaker where intelligent FTU in main differential ring outputs
Trip command, through delay Δ T=T after a period of timep+Tpb, TpFor circuit breaker trip maximum time, TpbFor time margin, break
The road device tripping non-set of information in place, judges itself breaker tripping.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810551482.8A CN108683161B (en) | 2018-05-31 | 2018-05-31 | Differential backup protection method applied to intelligent power distribution network |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810551482.8A CN108683161B (en) | 2018-05-31 | 2018-05-31 | Differential backup protection method applied to intelligent power distribution network |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108683161A true CN108683161A (en) | 2018-10-19 |
| CN108683161B CN108683161B (en) | 2020-04-03 |
Family
ID=63809539
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810551482.8A Active CN108683161B (en) | 2018-05-31 | 2018-05-31 | Differential backup protection method applied to intelligent power distribution network |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108683161B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109613394A (en) * | 2018-11-30 | 2019-04-12 | 广东电网有限责任公司 | A kind of intelligent distribution making alive time type fault section method of discrimination on the spot |
| CN109980616A (en) * | 2019-04-02 | 2019-07-05 | 国网江苏省电力有限公司镇江供电分公司 | The guard method of 110kV single-trunk segmental wiring integration protective device |
| CN110912090A (en) * | 2019-11-27 | 2020-03-24 | 电子科技大学 | Rapid intervention method for backup protection of electric power system distance II section |
| CN114530834A (en) * | 2022-02-23 | 2022-05-24 | 南京国电南自电网自动化有限公司 | Power distribution network line current locking type incomplete differential protection method |
| CN117081013A (en) * | 2023-08-24 | 2023-11-17 | 常熟理工学院 | Feedforward type overcurrent backup protection method and system for low-voltage distribution line |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7751166B2 (en) * | 2007-03-16 | 2010-07-06 | Abb Technology Ag | Advanced feeder architecture with automated power restoration |
| CN106230121A (en) * | 2016-09-21 | 2016-12-14 | 湖南大学 | A kind of self-adaptive healing guard method being applied to containing hybrid switch power distribution network |
| CN106786522A (en) * | 2016-12-16 | 2017-05-31 | 湖南世优电力科技股份有限公司 | Intelligent distribution network self-healing control method based on peer-to-peer communication network |
| CN107204663A (en) * | 2017-06-05 | 2017-09-26 | 湖南大学 | A kind of back-up protection method of distributed intelligence power distribution network |
-
2018
- 2018-05-31 CN CN201810551482.8A patent/CN108683161B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7751166B2 (en) * | 2007-03-16 | 2010-07-06 | Abb Technology Ag | Advanced feeder architecture with automated power restoration |
| CN106230121A (en) * | 2016-09-21 | 2016-12-14 | 湖南大学 | A kind of self-adaptive healing guard method being applied to containing hybrid switch power distribution network |
| CN106786522A (en) * | 2016-12-16 | 2017-05-31 | 湖南世优电力科技股份有限公司 | Intelligent distribution network self-healing control method based on peer-to-peer communication network |
| CN107204663A (en) * | 2017-06-05 | 2017-09-26 | 湖南大学 | A kind of back-up protection method of distributed intelligence power distribution network |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109613394A (en) * | 2018-11-30 | 2019-04-12 | 广东电网有限责任公司 | A kind of intelligent distribution making alive time type fault section method of discrimination on the spot |
| CN109613394B (en) * | 2018-11-30 | 2021-04-02 | 广东电网有限责任公司 | Intelligent distributed voltage-adding time type in-situ fault section discrimination method |
| CN109980616A (en) * | 2019-04-02 | 2019-07-05 | 国网江苏省电力有限公司镇江供电分公司 | The guard method of 110kV single-trunk segmental wiring integration protective device |
| CN110912090A (en) * | 2019-11-27 | 2020-03-24 | 电子科技大学 | Rapid intervention method for backup protection of electric power system distance II section |
| CN110912090B (en) * | 2019-11-27 | 2021-05-14 | 电子科技大学 | Rapid intervention method for backup protection of electric power system distance II section |
| CN114530834A (en) * | 2022-02-23 | 2022-05-24 | 南京国电南自电网自动化有限公司 | Power distribution network line current locking type incomplete differential protection method |
| CN114530834B (en) * | 2022-02-23 | 2023-10-31 | 南京国电南自电网自动化有限公司 | Power distribution network line current locking type incomplete differential protection method |
| CN117081013A (en) * | 2023-08-24 | 2023-11-17 | 常熟理工学院 | Feedforward type overcurrent backup protection method and system for low-voltage distribution line |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108683161B (en) | 2020-04-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108683161A (en) | A kind of differential back-up protection method applied to intelligent distribution network | |
| Swathika et al. | Prims-aided Dijkstra algorithm for adaptive protection in microgrids | |
| CN107204663B (en) | Backup protection method for distributed intelligent power distribution network | |
| US11611210B2 (en) | Tie switch restoration | |
| CN106527394B (en) | A kind of ECPS cascading failure methods of risk assessment considering multiple information factor | |
| CN103296643B (en) | Comparative isolated island detection and protection method based on wide range information phase difference | |
| CN104242274A (en) | State variable differential protection method for power distribution network accessing to distributed power supply | |
| CN112736870B (en) | Adjacent cooperative remote backup protection method | |
| CN101714756B (en) | Equivalent negative sequence impedance-based distributed generator islanding protection method | |
| CN112886557B (en) | Power distribution network main station and level difference protection coordination type self-healing method | |
| CN108075438A (en) | A kind of method of self-adaptive sites protective device definite value | |
| CN104201645A (en) | Differential protection method for preventing abnormally great number of sampling values | |
| CN107368966A (en) | A kind of appraisal procedure of electric power networks fragility | |
| Ling et al. | A distributed fault localization, isolation and supply restoration algorithm based on local topology | |
| Maiola et al. | A multi-agent system for protection coordination of radial systems in the presence of distributed generation | |
| CN108919055A (en) | A kind of photovoltaic Fault Diagnosis Method for Distribution Networks of roof containing high density based on Petri network | |
| CN105470934B (en) | A kind of power distribution network automatic reclosing control method suitable for distributed generation resource access | |
| CN114386222A (en) | Power distribution network cooperative fault recovery method and system based on information physical system | |
| CN104882904A (en) | Novel photovoltaic power station passive anti-islanding protection method | |
| CN108616114A (en) | A kind of power distribution network distributed layer protection system and method for the group containing microgrid | |
| CN110336383B (en) | Distribution network feeder automatic system | |
| CN104009453B (en) | A kind of fault detection method for micro-capacitance sensor off-grid operation situation | |
| CN103779852B (en) | Based on area protection system and the method thereof of adaptive Current Protection cofactor | |
| CN106451444B (en) | A kind of power grid cascading failure accident chaining search method considering removal of load and coupling | |
| CN109638817A (en) | A kind of power distribution network fragility point analysis and prevention and control method considering user side model |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |