CN110417030A - A kind of Distributed localization method and system of electric system forced oscillation - Google Patents

A kind of Distributed localization method and system of electric system forced oscillation Download PDF

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Publication number
CN110417030A
CN110417030A CN201910593572.8A CN201910593572A CN110417030A CN 110417030 A CN110417030 A CN 110417030A CN 201910593572 A CN201910593572 A CN 201910593572A CN 110417030 A CN110417030 A CN 110417030A
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data collector
local
oscillation
phasor data
energy stream
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CN110417030B (en
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吴熙
陈曦
吕万
王梦婷
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Southeast University
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Southeast University
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/08—Locating faults in cables, transmission lines, or networks
    • G01R31/081—Locating faults in cables, transmission lines, or networks according to type of conductors
    • G01R31/086—Locating faults in cables, transmission lines, or networks according to type of conductors in power transmission or distribution networks, i.e. with interconnected conductors
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/24—Arrangements for preventing or reducing oscillations of power in networks
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
    • Y02E40/70—Smart grids as climate change mitigation technology in the energy generation sector
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
    • Y04S10/00—Systems supporting electrical power generation, transmission or distribution
    • Y04S10/12—Monitoring or controlling equipment for energy generation units, e.g. distributed energy generation [DER] or load-side generation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
    • Y04S10/00—Systems supporting electrical power generation, transmission or distribution
    • Y04S10/22—Flexible AC transmission systems [FACTS] or power factor or reactive power compensating or correcting units

Abstract

The invention discloses a kind of Distributed localization method and system of electric system forced oscillation, construct a kind of layered distribution type multi-agent system frame towards forced oscillation positioning, the oscillation energy stream of power grid cut set is obtained by the information exchange between the information processing on the spot of local phasor data collector and local phasor data collector, pass through the cut set where oscillation energy stream Trend judgement forced oscillation, forced oscillation is positioned from distributed angle, can satisfy the reliability and requirement of real-time of positioning.

Description

A kind of Distributed localization method and system of electric system forced oscillation
Technical field
The present invention relates to Operation of Electric Systems analyses, more particularly to a kind of Distributed localization of electric system forced oscillation Method and system.
Background technique
As the access and more and more power electronic equipments of the renewable energy such as large-scale wind-powered electricity generation, photovoltaic are in electricity Use in net, the power disturbance source quantity in electric system is increasing, and disturbance form is more diversified, forced oscillation problem It becomes increasingly conspicuous, has seriously affected system power conveying and system stability.For forced oscillation problem, if disturbing source is not eliminated, Oscillation can be continued for, and find and excision oscillation source is the major measure for coping with forced oscillation in time.
In the case where NETWORK STRUCTURE PRESERVING POWER SYSTEM is increasingly complicated, the reason of oscillation, is analyzed, to vibration from mathematics mechanism It swings source and carries out positioning investigation more difficulty, and surveyed based on phasor measuring set (Phasor Measurement Unit, PMU) Signal, which carries out oscillatory regime monitoring and analysis, can overcome the limitation based on mathematics mechanism analysis method, obtain electric system vibration It swings characteristic and carries out the positioning of oscillation source.But since electric system is huge, PMU is large number of, is uploaded to WAMS main website Phasor data amount it is very big, and data during being transmitted to main website it sometimes appear that mistake phenomenon.WAMS main website into The centralization identification and positioning of row forced oscillation, computationally intensive, communicating requirement is high, it is difficult to meet the reliability and reality of oscillation test The requirement of when property.Therefore, it is necessary to be positioned from distributed angle to forced oscillation, to meet the requirement of oscillation on-line checking.
Summary of the invention
Goal of the invention: the object of the present invention is to provide a kind of Distributed localization method of electric system forced oscillation and it is System, can position forced oscillation from distributed angle, to meet the requirement of oscillation on-line checking.
Technical solution: to reach this purpose, the invention adopts the following technical scheme:
The Distributed localization method of electric system forced oscillation of the present invention, comprising the following steps:
S1: start to update the oscillation energy stream of all cut sets, be t at the time of note starts；
S2: local phasor data collector collects the data of coupled phasor measurement unit, enables i=1；
S3: local phasor data collector is to ACiIt is checked, wherein CiFor in n cut set being divided into power grid I cut set, ACiFor i-th of cut set CiAncillary control information: if ACiIn only comprising a local phasor data collector, C is then calculated by the local phasor data collectoriOscillation energy stream, then go to step S6；Otherwise, step S4 is carried out；
S4: local phasor data collector calculates CiPart oscillation energy stream；
S5: the C that local phasor data collector obtains step S4iPart oscillation energy stream and one's respective area in other locals Phasor data collector interacts, and C is calculatediComplete oscillation can flow；
S6: C is updatediIn the oscillation energy stream of moment t；
S7: if the oscillation energy stream of all cut sets is all updated, carrying out step S7, otherwise enables i=i+1 and returns to step Rapid S3；
S8: judge whether t reaches preset time: if it is, carrying out step S9；Otherwise, every t1Time enables t=t+t1, Return step S1；
S9: the positioning of forced oscillation is realized by the trend of the oscillation energy stream of all cut sets.
Further, it in the step S5, is interacted between local phasor data collector by average homogeneity algorithm.
Further, in the step S3, CiOscillation energy stream be calculated by formula (1):
In formula (1),For CiOscillation energy stream, vj PDCFor j-th of local phasor data collector,It is j-th Local phasor data collector vj PDCThe cut set C that can be obtained before being interacted with other PDCiPart oscillation energy stream, pass through formula (2) it is calculated；
In formula (2), line set BjIndicating can be by j-th of local phasor data collector vj PDCMeasure the institute of data There is the set of route；(x, y) indicates line set BjIn route, x indicates that an end node of route, y indicate route Another end node, WxyIndicate that the line oscillation that node y is flowed into from node x can flow.
Further, in the step S5, CiComplete oscillation can flow and be calculated by formula (3):
In formula (3),For CiComplete oscillation can flow, m is the total number of local phasor data collector, For the data obtained after the completion of each local phasor data collector interaction, it is calculated by formula (4)；
The Distributed positioning system of electric system forced oscillation of the present invention, including local layer and control centre's layer； Local layer includes at least one region, and each region includes at least one local phasor data collector, each local phasor Data collector all connects phasor measurement unit, and each local phasor data collector can be communicated and be calculated, in region All local phasor data collectors transmitted by dedicated network and shared information, local phasor data collector with control It is communicated between the central phasor data collector of central layer；Control centre's layer includes central phasor data collector, central phase Amount data collector is for updating the ancillary control information between local phasor data collector and being issued to local phasor data Collector is interacted between each local phasor data collector, the Distributed localization method using Distributed localization method For the Distributed localization method of the electric system forced oscillation.
Further, the power grid in the region is divided into multiple cut sets, and the ancillary control information includes each cut set institute The line information and the route can be measured that the information of the bus or node that include, each cut set are connected with remaining power grid The information of the connected local phasor data collector of the phasor measurement unit of oscillation energy stream.
The utility model has the advantages that the invention discloses a kind of Distributed localization method and system of electric system forced oscillation, building A kind of layered distribution type multi-agent system frame towards forced oscillation positioning, by local phasor data collector on the spot Information processing and local phasor data collector between information exchange obtain the oscillation energy stream of power grid cut set, pass through oscillation The cut set where Trend judgement forced oscillation can be flowed, forced oscillation is positioned from distributed angle, can satisfy positioning Reliability and requirement of real-time.
Detailed description of the invention
Fig. 1 is the framework map of system involved in method in the specific embodiment of the invention；
Fig. 2 is the framework map of method in the specific embodiment of the invention；
Fig. 3 is that certain power grid is divided into several schematic diagrames that can be monitored cut set in the specific embodiment of the invention；
Fig. 4 is the specific flow chart of method in the specific embodiment of the invention；
Fig. 5 is the schematic diagram of IEEE39 node typical case's power grid in the specific embodiment of the invention；
Fig. 6 is to vibrate energy flow chart using all cut sets that this method detects in the specific embodiment of the invention；
Fig. 7 is the information interactive process figure in the specific embodiment of the invention between the PDC of local.
Specific embodiment
Technical solution of the present invention is further introduced With reference to embodiment.
Present embodiment discloses a kind of Distributed positioning system of electric system forced oscillation, as shown in Figure 1, packet Include local layer and control centre's layer；Local layer includes at least one region, and each region includes at least one local phasor number According to collector, each local phasor data collector connects phasor measurement unit, and each local phasor data collector It can communicate and calculate, all local phasor data collectors in region are transmitted by dedicated network and shared information, local It is communicated between phasor data collector and the central phasor data collector of control centre layer；Control centre's layer includes center Phasor data collector, central phasor data collector are used to update the ancillary control information between local phasor data collector And it is issued to local phasor data collector, it is handed between each local phasor data collector using Distributed localization method Mutually, Distributed localization method is the Distributed localization method of electric system forced oscillation.
Power grid in region is divided into multiple cut sets, as shown in figure 3, ancillary control information includes that each cut set is included Line information that the information of bus or node, each cut set are connected with remaining power grid and the oscillation energy stream that route can be measured The information of the connected local phasor data collector of phasor measurement unit.
Present embodiment also discloses a kind of Distributed localization method of electric system forced oscillation, such as Fig. 2 and Fig. 4 It is shown, comprising the following steps:
S1: start to update the oscillation energy stream of all cut sets, be t at the time of note starts；
S2: local phasor data collector collects the data of coupled phasor measurement unit, enables i=1；
S3: local phasor data collector is to ACiIt is checked, wherein CiFor in n cut set being divided into power grid I cut set, as shown in figure 3, ACiFor i-th of cut set CiAncillary control information: if ACiIn only comprising a local phasor number According to collector, then C is calculated by the local phasor data collectoriOscillation energy stream, then go to step S6；Otherwise, it carries out Step S4；
S4: local phasor data collector calculates CiPart oscillation energy stream；
S5: the C that local phasor data collector obtains step S4iPart oscillation energy stream and one's respective area in other locals Phasor data collector interacts, and C is calculatediComplete oscillation can flow；
S6: C is updatediIn the oscillation energy stream of moment t；
S7: if the oscillation energy stream of all cut sets is all updated, carrying out step S7, otherwise enables i=i+1 and returns to step Rapid S3；
S8: judge whether t reaches preset time: if it is, carrying out step S9；Otherwise, every t1Time enables t=t+t1, Return step S1；
S9: the positioning of forced oscillation is realized by the trend of the oscillation energy stream of all cut sets.
In step S8, t1It is 0.1 second.
In step S5, interacted between local phasor data collector by average homogeneity algorithm.
In step S3, CiOscillation energy stream be calculated by formula (1):
In formula (1),For CiOscillation energy stream, vj PDCFor j-th of local phasor data collector,It is j-th Local phasor data collector vj PDCThe cut set C that can be obtained before being interacted with other PDCiPart oscillation energy stream, pass through formula (2) it is calculated；
In formula (2), line set BjIndicating can be by j-th of local phasor data collector vj PDCMeasure the institute of data There is the set of route；(x, y) indicates line set BjIn route, x indicates that an end node of route, y indicate route Another end node, WxyIndicate that the line oscillation that node y is flowed into from node x can flow.
In step S5, CiComplete oscillation can flow and be calculated by formula (3):
In formula (3),For CiComplete oscillation can flow, m is the total number of local phasor data collector, For the data obtained after the completion of each local phasor data collector interaction, it is calculated by formula (4)；
It is tested in IEEE39 node modular system as shown in Figure 5, which is divided into following 29 cut sets:
The sinusoidal load disturbance of frequency 0.57Hz, 5MW is added on the load of node 18, uses Distributed localization method The measurement of oscillation energy stream is carried out, the cut set oscillation energy stream of each local PDC monitoring is as shown in Figure 6.Local PDC is obtained in 2s The interactive process of 17,19,20 oscillation energy stream of cut set is as shown in Figure 7.It can be seen that this method passes through the distribution between the PDC of local Forced oscillation, has accurately been located among cut set 21, has illustrated the validity of method by formula cooperation.

Claims (6)

1. a kind of Distributed localization method of electric system forced oscillation, it is characterised in that: the following steps are included:
S1: start to update the oscillation energy stream of all cut sets, be t at the time of note starts；
S2: local phasor data collector collects the data of coupled phasor measurement unit, enables i=1；
S3: local phasor data collector is to ACiIt is checked, wherein CiFor i-th in n cut set being divided into power grid Cut set, ACiFor i-th of cut set CiAncillary control information: if ACiIn only comprising a local phasor data collector, then by The local phasor data collector calculates CiOscillation energy stream, then go to step S6；Otherwise, step S4 is carried out；
S4: local phasor data collector calculates CiPart oscillation energy stream；
S5: the C that local phasor data collector obtains step S4iPart oscillation energy stream and one's respective area in other local phasors Data collector interacts, and C is calculatediComplete oscillation can flow；
S6: C is updatediIn the oscillation energy stream of moment t；
S7: if the oscillation energy stream of all cut sets is all updated, carrying out step S7, otherwise enables i=i+1 and return step S3；
S8: judge whether t reaches preset time: if it is, carrying out step S9；Otherwise, every t1Time enables t=t+t1, return Step S1；
S9: the positioning of forced oscillation is realized by the trend of the oscillation energy stream of all cut sets.
2. the Distributed localization method of electric system forced oscillation according to claim 1, it is characterised in that: the step In S5, interacted between local phasor data collector by average homogeneity algorithm.
3. the Distributed localization method of electric system forced oscillation according to claim 1, it is characterised in that: the step In S3, CiOscillation energy stream be calculated by formula (1):
In formula (1),For CiOscillation energy stream,For j-th of local phasor data collector,It is local for j-th Phasor data collectorThe cut set C that can be obtained before being interacted with other PDCiPart oscillation energy stream, pass through formula (2) It is calculated；
In formula (2), line set BjIndicating can be by j-th of local phasor data collectorThe institute for measuring data is wired The set on road；(x, y) indicates line set BjIn a route, x indicate route an end node, y indicate route it is another End node, WxyIndicate that the line oscillation that node y is flowed into from node x can flow.
4. the Distributed localization method of electric system forced oscillation according to claim 1, it is characterised in that: the step In S5, CiComplete oscillation can flow and be calculated by formula (3):
In formula (3),For CiComplete oscillation can flow, m is the total number of local phasor data collector,It is every The data obtained after the completion of a local phasor data collector interaction, are calculated by formula (4)；
5. a kind of Distributed positioning system of electric system forced oscillation, it is characterised in that: including local layer and control centre's layer； Local layer includes at least one region, and each region includes at least one local phasor data collector, each local phasor Data collector all connects phasor measurement unit, and each local phasor data collector can be communicated and be calculated, in region All local phasor data collectors transmitted by dedicated network and shared information, local phasor data collector with control It is communicated between the central phasor data collector of central layer；Control centre's layer includes central phasor data collector, central phase Amount data collector is for updating the ancillary control information between local phasor data collector and being issued to local phasor data Collector is interacted between each local phasor data collector, the Distributed localization method using Distributed localization method For the Distributed localization method of electric system forced oscillation described in claim 1.
6. the Distributed positioning system of electric system forced oscillation according to claim 5, it is characterised in that: the region Interior power grid is divided into multiple cut sets, the ancillary control information include the bus that each cut set is included or node information, The phasor measurement unit phase of line information and the oscillation energy stream that the route can be measured that each cut set is connected with remaining power grid The information of local phasor data collector even.
CN201910593572.8A 2019-07-03 2019-07-03 Distributed positioning method and system for forced oscillation of electric power system Active CN110417030B (en)

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104242462A (en) * 2014-10-08 2014-12-24 中国南方电网有限责任公司 WAMS (wide area measurement system) and SCADA (supervisory control and data acquisition) integrated data based grid forced oscillation source positioning method
CN109001556A (en) * 2018-05-31 2018-12-14 国网四川省电力公司电力科学研究院 One type forces the method for discrimination and system of ultra-low frequency oscillation

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104242462A (en) * 2014-10-08 2014-12-24 中国南方电网有限责任公司 WAMS (wide area measurement system) and SCADA (supervisory control and data acquisition) integrated data based grid forced oscillation source positioning method
CN109001556A (en) * 2018-05-31 2018-12-14 国网四川省电力公司电力科学研究院 One type forces the method for discrimination and system of ultra-low frequency oscillation

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