CN102882196A - Fault isolation method for distribution network containing distributed power sources - Google Patents
Fault isolation method for distribution network containing distributed power sources Download PDFInfo
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- CN102882196A CN102882196A CN2012104070697A CN201210407069A CN102882196A CN 102882196 A CN102882196 A CN 102882196A CN 2012104070697 A CN2012104070697 A CN 2012104070697A CN 201210407069 A CN201210407069 A CN 201210407069A CN 102882196 A CN102882196 A CN 102882196A
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Abstract
The invention discloses a fault isolation method for a distribution network containing distributed power sources. The method relies on an EPON (Ethernet passive optical network) system of the distribution network and realizes complete coverage of optical fiber communication of power distribution terminals, and the EPON system preferentially adopts double networks. By the fault isolation method for the distribution network containing the distributed power sources, quick fault positioning and isolation of the distribution network containing the distributed power sources are realized, influences of faults are isolated within a minimum range, damage degree of faulted elements is reduced, low-voltage time of a load is reduced, and normal power supply of non-faulted areas in the power distribution network is guaranteed; and the distributed power sources can be quickly removed when faulted, so that safe operation of the power distribution network and other distributed power sources is guaranteed, and power supply capability of the distributed power sources is improved.
Description
Technical field
The present invention relates to a kind of Distribution Network Failure partition method that contains distributed power source, belong to distribution field, relaying protection field and communication field.
Background technology
Because the increase in demand of global energy, various countries help wind power generation, solar power generation and other clean electric power generation technology one after another in the world, China is in the face of the few electric problem of short of electricity of energy shortage, rural area and remote districts, greatly develop the new forms of energy construction during " 12 ", government is subsidized in rate for incorporation into the power network, as replenishing of large electrical network, access on the spot power distribution network.Behind the distributed power source access power distribution network, although solved powerup issue, how to prevent that the distributed power source faults itself from having impacted into a new problem distribution.
Traditional power distribution network protective relaying device disperses to install; the overcurrent protection of each protective device cooperatively interacts by sequential; transformer station's 10KV exit fast tripping protection because and the time coordination requirement of higher level protection; general setting time is no more than 0.3S; how to excise selectively the fault on the circuit, the interruption duration that reduces the user has become a research direction.Although optical-fiber longitudinal difference, can solve selective protection based on the protection of synchronous sampling technique, to communication speed require highly, and cost of investment is large, is not adapted at promoting in the distribution.
Power distribution automation transformation along with a new round, the EPON technology gets a lot of applications in distribution, formed fast communication network between the distribution terminal on the distribution line, utilize between the direction overcurrent element of distribution terminal and the distribution terminal mutually latching relation, can accomplish quick location and the isolation of Distribution Network Failure, guarantee the normal operation of non-fault zone.
Summary of the invention
Goal of the invention: in order to overcome the deficiencies in the prior art, the invention provides a kind of joining of distributed power source that contain
The net failure separation method may further comprise the steps:
Step (1): file is put in assembling under each distribution terminal, and configuration file comprises the corresponding relation between device address and the both forward and reverse directions startup sign table, the locking contingency table of both forward and reverse directions overcurrent protection;
Step (2): distribution terminal increases direction overcurrent starting component, and direction overcurrent starting component moves backward distribution terminal and sends both forward and reverse directions overcurrent starting state;
Step (3): resolve the positive and negative direction overcurrent starting state that distribution terminal transmits, and be filled up in the corresponding positive and negative direction startup sign table according to corresponding relation;
Step (4): after distribution terminal direction overcurrent starts; at in setting time; search the start bit that both forward and reverse directions starts the sign table according to the locking flag bit in the both forward and reverse directions overcurrent protection locking contingency table, comprehensively all need to determine whether directional over-current protection moves behind the related starting state.
Described step (1) specifically refers to:
1a) distribution terminal in a zone needing on the distribution line to cooperate by sequential is unified configuration, according to the address difference it is set and starts correspondence position in the sign table at both forward and reverse directions, positive direction and reciprocal startup sign table are separate;
1b) to each distribution terminal, dispose two locking contingency tables, respectively positive direction overcurrent action locking contingency table and the locking of overcurrent action in the other direction contingency table, be used for arranging the device identification in this distribution terminal positive and negative direction downstream, corresponding with the flag bit that both forward and reverse directions starts in the sign table, locking contingency table flag bit is set to 1, then needs to check the starting state that starts correspondence position in the sign table, locking contingency table flag bit is set to 0, does not then need to check; If distribution terminal is not thrown direction component, then need simultaneously upstream device locking contingency table flag bit to be set to 1.
Described step (2) specifically refers to: distribution terminal increases positive and negative direction overcurrent starting component, direction overcurrent starting component moves backward distribution terminal and sends both forward and reverse directions overcurrent starting state: during distribution terminal CT/PT wiring, to be that positive direction is carried out polarity unified according to pointed to load side, distributed power source by transformer station, for the Double-End Source of cyclization operation, regulation is pointed to another transformer station take a transformer station, and to carry out polarity unified as positive direction;
The starting state communication of positive and negative direction overcurrent starting component sends and arranges respectively, is divided into three kinds of patterns: normally, do not send out and twocouese; After the direction overcurrent starts under normal circumstances, send the starting state of this direction to distribution terminal; The overcurrent starting component with direction is not set to twocouese, sends the both forward and reverse directions log-on message to distribution terminal simultaneously after starting; The opposite direction overcurrent starting component of distributed power source place distribution terminal should be set to not send out, and positive direction overcurrent starting component should be set to twocouese.
Beneficial effect: the Distribution Network Failure partition method that contains distributed power source provided by the invention, realization contains fast location and the isolation of Distribution Network Failure of distributed power source, the impact of fault is isolated in minimum zone, reduce the damaged condition of fault element, shorten the low-voltage time of load, guarantee the normal power supply of non-fault zone in the power distribution network; Can excise rapidly during the distributed power source fault, guarantee power distribution network and other distributed power source safe operations, improve the power supply capacity of distributed power source.
Description of drawings
Fig. 1 is the logic diagram that the present invention contains the Distribution Network Failure partition method of distributed power source;
Fig. 2 is the structured flowchart of EPON communication system among the present invention;
Fig. 3 is the structured flowchart that the present invention contains the distribution model of distributed power source.
Embodiment
Below in conjunction with accompanying drawing the present invention is further described.
The present invention is the EPON communication system that relies on power distribution network, realize the optical-fibre communications all standing of distribution terminal, the EPON system is take two nets as good, be illustrated in figure 2 as EPON communication system among the present invention, utilize EPON EPON communication system, the place arranges optical line terminal OLT equipment at the 10KV line outlet, optical network unit ONU is installed on switching station, ring main unit, on-pole switchs etc. are located, OLT joins ODN by light and optical splitter ODF links to each other with ONU, and linked to each other by netting twine eventually with near distribution by ONU, the communication that realizes the 10KV distribution automation covers, reliable for communication network, and EPON is take two nets as good.
Direction component adopts 90 ° of wiring, regulation by transformer station point to load side, distributed power source is positive direction, Double-End Source for the cyclization operation, can set arbitrarily take a transformer station and point to another transformer station as positive direction, all direction components should be consistent in network, and are as follows with the of ac corresponding relation:
| Direction component | DA | DB | DC |
| Ir | Ia | Ib | Ic |
| Ur | Ubc | Uca | Uab |
The positive direction operation equation is
Operation equation is in the other direction
Voltage dead band when adopting memory voltage to eliminate the near region three-phase shortcircuit, the dead band line is established certain voltage threshold value." near region three-phase fault " refer to protect three-phase all to start and three-phase line voltage less than threshold value.During the near region three-phase shortcircuit, identical with the direction that drops into of adjusting such as the fault sense of current, the directional over-current protection i.e. action excision fault of delaying time, opposite with the incidence of adjusting such as the fault sense of current, protect immediately locking.
Be illustrated in figure 1 as a kind of Distribution Network Failure partition method that contains distributed power source, may further comprise the steps:
Step (1): file is put in assembling under each distribution terminal, and configuration file comprises the corresponding relation between device address and the both forward and reverse directions startup sign table, the locking contingency table of both forward and reverse directions overcurrent protection;
1a) distribution terminal in a zone needing on the distribution line to cooperate by sequential is unified configuration, according to the address difference it is set and starts correspondence position in the sign table at both forward and reverse directions, positive direction and reciprocal startup sign table are separate;
1b) to each distribution terminal, dispose two locking contingency tables, respectively positive direction overcurrent action locking contingency table and the locking of overcurrent action in the other direction contingency table, be used for arranging the device identification in the positive and negative side of this distribution terminal downstream, corresponding with the flag bit that both forward and reverse directions starts in the sign table, locking contingency table flag bit is set to 1, then needs to check the starting state that starts correspondence position in the sign table, locking contingency table flag bit is set to 0, does not then need to check; If distribution terminal is not thrown direction component, then need simultaneously upstream device locking contingency table flag bit to be set to 1;
Step (2): distribution terminal increases direction overcurrent starting component, and direction overcurrent starting component moves backward distribution terminal and sends both forward and reverse directions overcurrent starting state; Distribution terminal increases positive and negative direction overcurrent starting component, direction overcurrent starting component moves backward distribution terminal and sends both forward and reverse directions overcurrent starting state: during distribution terminal CT/PT wiring, to be that positive direction is carried out polarity unified according to pointed to load side, distributed power source by transformer station, for the Double-End Source of cyclization operation, regulation is pointed to another transformer station take a transformer station, and to carry out polarity unified as positive direction;
The starting state communication of positive and negative direction overcurrent starting component sends and arranges respectively, is divided into three kinds of patterns: normally, do not send out and twocouese; After the direction overcurrent starts under normal circumstances, send the starting state of this direction to distribution terminal; The overcurrent starting component with direction is not set to twocouese, sends the both forward and reverse directions log-on message to distribution terminal simultaneously after starting; The opposite direction overcurrent starting component of distributed power source place distribution terminal should be set to not send out, and positive direction overcurrent starting component should be set to twocouese;
Step (3): resolve the positive and negative direction overcurrent starting state that distribution terminal transmits, and be filled up in the corresponding positive and negative direction startup sign table according to corresponding relation;
Step (4): after distribution terminal direction overcurrent starts; at in setting time; search the start bit that both forward and reverse directions starts the sign table according to the locking flag bit in the both forward and reverse directions overcurrent protection locking contingency table, comprehensively all need to determine whether directional over-current protection moves behind the related starting state.
Contain as shown in Figure 3 in the distribution model of distributed power source; suppose and take the cyclization operational mode; power direction points to load, distributed power source and transformer station 2 by transformer station 1; transformer station's exit K switch 1, K14 current quick operation time limit are adjusted into 0.3S; the K switch 2-K7 protection of distributed power source drops into positive direction current quick-breaking section; opposite direction overcurrent delay section; the protection of on-load switch K8-K13 place drops into the current quick-breaking section, and block switch FD1-FD3, the protection of interconnection switch LL place drop into positive direction current quick-breaking section, opposite direction current quick-breaking section.
Forward and reverse log-on message flag bit and the locking flag bit of K2-K13, FD1-FD3, LL define respectively:
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | … |
| K2 | K3 | K4 | K5 | K6 | K7 | K8 | K9 | K10 | K11 | K12 | K13 | FD1 | FD2 | FD3 | LL | ? |
When locking checks, the locking flag bit perseverance of self is 0, the positive direction locking flag bit that sets in advance for FD1 is: 00111100-11110111, the flag bit of locking in the other direction is: 11000011-00000000, the positive direction locking flag bit that sets in advance for FD2 is: 00001100-00110011, the flag bit of locking in the other direction is: 11110011-11001000, the positive direction locking flag bit that sets in advance for FD3 is: 00000000-00000001, the flag bit of locking in the other direction is: 11111111-11111100.All the other on-load switches, distributed power source locking flag bit are 0.
When the F1 fault; it is 00000000-10001000 that each distribution terminal forward starts flag bit; the reverse starting flag bit is 00000000-10000111; the positive and negative direction of each distribution terminal starts flag bit and positive and negative direction locking flag bit mutually with rear non-vanishing; the opposite direction fast tripping protection of the positive direction fast tripping protection of FD1 and FD2, FD3, LL is blocked, the only current quick of K10 action.
When the F2 fault; it is 00000000-00001000 that each distribution terminal forward starts flag bit; the reverse starting flag bit is 00000000-00000111; the forward of FD1 start flag bit and forward locking flag bit mutually with after be zero; without locking; the action of positive direction fast tripping protection; the reverse starting flag bit of FD2 and reverse locking flag bit mutually with after be zero; without locking; fast tripping protection action in the other direction, FD3; LL starts flag bit and locking flag bit in the other direction in the other direction mutually with rear non-vanishing, FD3; the opposite direction current quick of LL is blocked; FD1; after the FD2 excision, distributed power source is by K4; K5 overcurrent protection in the other direction excision or self inspection island protect excision.
When the F3 fault; it is 00100000-00001000 that each distribution terminal forward starts flag bit; the reverse starting flag bit is 00100000-00000111; the positive and negative direction of each distribution terminal starts flag bit and positive and negative direction locking flag bit mutually with rear non-vanishing; the opposite direction fast tripping protection of the positive direction fast tripping protection of FD1 and FD2, FD3, LL is blocked, the only positive direction fast tripping protection of K4 action.
When the F4 fault; it is 00000000-00001111 that each distribution terminal forward starts flag bit; the reverse starting flag bit is 00000000-00000000; the positive direction of FD1, FD2, FD3 starts flag bit and positive direction locking flag bit mutually with rear non-vanishing; the positive direction fast tripping protection of FD1, FD2, FD3 is blocked, and the positive direction fast tripping protection of LL then will cooperate with each distribution terminal of interconnection right side.
During operation with closed ring everywhere the action situation of fault analyze no longer one by one, for the open loop operational mode, this method is still applicable.
The above only is preferred implementation of the present invention; be noted that for those skilled in the art; under the prerequisite that does not break away from the principle of the invention, can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.
Claims (3)
1. Distribution Network Failure partition method that contains distributed power source may further comprise the steps:
Step (1): file is put in assembling under each distribution terminal, and configuration file comprises the corresponding relation between device address and the both forward and reverse directions startup sign table, the locking contingency table of both forward and reverse directions overcurrent protection;
Step (2): distribution terminal increases direction overcurrent starting component, and direction overcurrent starting component moves backward distribution terminal and sends both forward and reverse directions overcurrent starting state;
Step (3): resolve the positive and negative direction overcurrent starting state that distribution terminal transmits, and be filled up in the corresponding positive and negative direction startup sign table according to corresponding relation;
Step (4): after distribution terminal direction overcurrent starts; at in setting time; search the start bit that both forward and reverse directions starts the sign table according to the locking flag bit in the both forward and reverse directions overcurrent protection locking contingency table, comprehensively all need to determine whether directional over-current protection moves behind the related starting state.
2. the Distribution Network Failure partition method that contains distributed power source according to claim 1, it is characterized in that: described step (1) specifically refers to:
1a) distribution terminal in a zone needing on the distribution line to cooperate by sequential is unified configuration, according to the address difference it is set and starts correspondence position in the sign table at both forward and reverse directions, positive direction and reciprocal startup sign table are separate;
1b) to each distribution terminal, dispose two locking contingency tables, respectively positive direction overcurrent action locking contingency table and the locking of overcurrent action in the other direction contingency table, be used for arranging the device identification in this distribution terminal positive and negative direction downstream, corresponding with the flag bit that both forward and reverse directions starts in the sign table, locking contingency table flag bit is set to 1, then needs to check the starting state that starts correspondence position in the sign table, locking contingency table flag bit is set to 0, does not then need to check; If distribution terminal is not thrown direction component, then need simultaneously upstream device locking contingency table flag bit to be set to 1.
3. the Distribution Network Failure partition method that contains distributed power source according to claim 1 and 2, it is characterized in that: described step (2) specifically refers to: distribution terminal increases positive and negative direction overcurrent starting component, direction overcurrent starting component moves backward distribution terminal and sends both forward and reverse directions overcurrent starting state: during distribution terminal CT/PT wiring, to be that positive direction is carried out polarity unified according to pointed to load side, distributed power source by transformer station, for the Double-End Source of cyclization operation, regulation is pointed to another transformer station take a transformer station, and to carry out polarity unified as positive direction; The starting state communication of positive and negative direction overcurrent starting component sends and arranges respectively, is divided into three kinds of patterns: normally, do not send out and twocouese; After the direction overcurrent starts under normal circumstances, send the starting state of this direction to distribution terminal; The overcurrent starting component with direction is not set to twocouese, sends the both forward and reverse directions log-on message to distribution terminal simultaneously after starting; The opposite direction overcurrent starting component of distributed power source place distribution terminal should be set to not send out, and positive direction overcurrent starting component should be set to twocouese.
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| CN103354353A (en) * | 2013-06-24 | 2013-10-16 | 国家电网公司 | Intelligent power-distribution-network whole-line quick-reacting main protection and determination system and method |
| CN106253251A (en) * | 2016-08-25 | 2016-12-21 | 成都汉度科技有限公司 | A kind of intelligent distribution network fault partition method |
| CN107728002A (en) * | 2017-08-23 | 2018-02-23 | 国网辽宁省电力有限公司经济技术研究院 | A kind of distribution network failure tuning on-line method for considering distributed power source access |
| CN111525511A (en) * | 2020-06-01 | 2020-08-11 | 攀钢集团西昌钢钒有限公司 | Generator and protection parameter setting method of circuit thereof |
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| CN111525511A (en) * | 2020-06-01 | 2020-08-11 | 攀钢集团西昌钢钒有限公司 | Generator and protection parameter setting method of circuit thereof |
| CN111525511B (en) * | 2020-06-01 | 2021-12-24 | 攀钢集团西昌钢钒有限公司 | Generator and protection parameter setting method of circuit thereof |
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