CN105024356B - A kind of 35kV and following voltage class ratiometric dynamic formula bus bar protecting method - Google Patents
A kind of 35kV and following voltage class ratiometric dynamic formula bus bar protecting method Download PDFInfo
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- CN105024356B CN105024356B CN201410581407.8A CN201410581407A CN105024356B CN 105024356 B CN105024356 B CN 105024356B CN 201410581407 A CN201410581407 A CN 201410581407A CN 105024356 B CN105024356 B CN 105024356B
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- 238000000034 method Methods 0.000 title claims abstract description 33
- 230000002633 protecting effect Effects 0.000 title claims abstract description 15
- 230000004224 protection Effects 0.000 claims abstract description 57
- 230000001681 protective effect Effects 0.000 claims abstract description 13
- 230000008569 process Effects 0.000 claims abstract description 12
- 230000003287 optical effect Effects 0.000 claims abstract description 7
- 238000004364 calculation method Methods 0.000 claims abstract description 5
- 230000009471 action Effects 0.000 claims abstract description 4
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims description 16
- 241000272814 Anser sp. Species 0.000 claims description 9
- 150000002170 ethers Chemical class 0.000 claims 1
- 238000006243 chemical reaction Methods 0.000 description 3
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- 238000004891 communication Methods 0.000 description 2
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- 230000005611 electricity Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
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- 238000012986 modification Methods 0.000 description 2
- 230000003111 delayed effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010891 electric arc Methods 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 230000006855 networking Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
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- 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
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- 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
- Y04S10/16—Electric power substations
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- 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
- Y04S10/20—Systems supporting electrical power generation, transmission or distribution using protection elements, arrangements or systems
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Abstract
A kind of 35kV of the present invention and following voltage class ratiometric dynamic formula bus bar protecting method, comprise the following steps：1) protective device of each element gathers the current and voltage signals at this interval and input and output signal in .35kV and following voltage class busbar, by being exported with the relevant network interface of optical cable to process-level network；2) current and voltage signals of protection equipment for transformers receive process layer network and input and output signal calculate the difference stream of all elements on busbar, after result of calculation meets operation condition, bus protection action.
Description
Technical field
The present invention relates to a kind of 35kV and following voltage class ratiometric dynamic formula bus bar protecting methods, and the invention belongs to intelligence
Substation relay protection field.
Background technology
It is expensive since busbar protective device is separately configured, and secondary circuit is complicated, substation 35kV and following voltage
The busbar of grade does not install special bus protection usually, generally cuts off bus-bar fault by the back-up protection delay tripping of transformer,
Delay is typically larger than 1.5s.It is long due to being delayed, when the busbar of 35kV and following voltage class break down, may lead
Transformer low voltage back-up protection is caused not yet to act, the power distribution equipment of each inlet-outlet line has been burnt on busbar.
With the rapid development of electric system, power system capacity constantly increases, and the short-circuit current level of system also increasingly improves.
When catastrophe failure occurs on 35kV and the busbar of following voltage class, it is likely that cause the damage of main transformer；Meanwhile switchgear
Interior electric arc can also scurry into secondary circuit, cause relay protection DC system fault, and whole station is caused to protect dead electricity, is caused more tight
The accident of weight.
Application No. 200810167954.6, invention and created name is " one kind is based on GOOSE mode networking bus bar protectings
The application for a patent for invention of method " discloses a kind of 35kV and the bus bar protecting method of following voltage class.Including：By related female
All outlet protection supervisory equipments, section switch protection supervisory equipment, incoming relay-protection measure and control device on line segment are (including transformation
The interface unit of device low-pressure side) coordinate the bus protection completed, it is characterized in that when electric power networks break down by scattered
Whether it is bus-bar fault that each protection location (measure and control device) judges fault currents flow direction to distinguish.The patent of invention is deposited
In following 3 limitations：1) patent of invention needs add bus protection on busbar in the protection supervisory equipment of all elements
Module, big to equipment change amount, complicated technology realization is of high cost；2) patent of invention is subject to substation 35kV at that time and following
Voltage class secondary device hardware is limited, and only acquires main transformer low-pressure side inlet wire current, it is impossible to obtain institute on busbar from process layer
There are element current data, the protection philosophy of ratio-restrained characteristic can not be used；3) actuation time is long, and whole group actuation time exists
More than 600ms, it is impossible to meet quick-action requirement.
The content of the invention
The object of the present invention is to provide a kind of 35kV and following voltage class ratiometric dynamic formula bus bar protecting method, to solve
Certainly existing 35kV and following voltage class bus protection principle are simple, reliability is low, quick-action is low, of high cost, realization complexity
Problem.
To achieve the above object, the solution of the present invention is a kind of 35kV and following voltage class ratiometric dynamic formula bus protection
Method comprises the following steps：
1) in .35kV and following voltage class busbar the protective device of each element gather this interval current and voltage signals and
Input and output signal, by being exported with the relevant network interface of optical cable to process-level network；
2) current and voltage signals of protection equipment for transformers receive process layer network and input and output signal calculate busbar
The difference stream of upper all elements, after result of calculation meets operation condition, bus protection action.
Current and voltage signals are analog signals, and are converted to IEC 61850-9-2 digital signals, and input and output signal is
Analog signals, and be converted to GOOSE digital signals.
Network interface is 100,000,000 luminiferous ether network interfaces；IEC 61850-9-2 and GOOSE data, pass through 100,000,000 luminiferous ether network interfaces
Access procedure layer network.
It is flowed using following operation equation to calculate the difference of all elements on busbar：
Id>Is
Id>KIr
Wherein：
I in formuladFor difference current；IrFor stalling current；K is ratio brake coefficient；ISFor difference current definite value；To be each
Loop current.
Protection equipment for transformer 35kV and following voltage class ratiometric dynamic formula bus protection configuration Sudden Changing Rate ratio brake
Differential protection function is fixed as 0.3 conventional ratio brake differential protection with restraint coefficient and is used cooperatively；Sudden Changing Rate ratio brake
Differential protection, operation equation are：
Id>0.3Ir
△Id>Is
△Id>0.7△Ir
Wherein：IsFor differential definite value；(For the electric current of j-th of connecting element
Sudden Changing Rate)。
The invention has the advantages that 1. economy is high, on the premise of protective device hardware cost is not increased, realize
35kV and following voltage class bus protection；2. quick-action is high, the electric current of all elements on busbar can be gathered, using based on can
By quick biased differential protection principle, whole group actuation time is not higher than 20ms；3. reliability is high, biased differential protection principle exists
It is widely used in China's electrical system bus protection, through runtime verification for many years, reliability is high, and malfunction, tripping probability are low；4. skill
Art is realized simple, it is only necessary to 35kV and following voltage class ratiometric dynamic formula bus protection, busbar are carried out in tranformer protection
The protective device function of upper each element is without changing；5. popularizing application prospect is good, the present invention is built suitable for China's intelligent substation
If cost can not increased, it is ensured that the security reliability operation of low-voltage bus bar possesses extensive popularization and application valency
Value.
Description of the drawings
Fig. 1 is main transformer 35kV parts main electrical scheme schematic diagram；
Fig. 2 is the 35kV ratiometric dynamic formula bus bar protecting method schematic diagrames of the embodiment of the present invention；
Fig. 3 is 35kV ratiometric dynamic formula bus protection operation curves.
Specific embodiment
The object of the present invention is to provide a kind of 35kV and following voltage class ratiometric dynamic formula bus bar protecting method, to solve
Certainly existing 35kV and following voltage class bus protection principle are simple, reliability is low, quick-action is low, of high cost, realization complexity
Problem.
The present invention will be further described in detail below in conjunction with the accompanying drawings.
Using 35kV ratiometric dynamic formula bus protections as specific embodiment, Fig. 1 show the main electrical scheme signal of main transformer 35kV parts
As shown in Figure 1, main transformer low-pressure side is 35kV, 5 35kV circuits are shared on 35kV busbares for figure.
35kV ratiometric dynamic formula bus bar protecting methods include：
1) protective device of each element gathers the current and voltage signals at this interval and input and output signal in .35kV busbares,
By being exported with the relevant network interface of optical cable to process-level network；
2) current and voltage signals of protection equipment for transformers receive process layer network and input and output signal calculate busbar
The difference stream of upper all elements, after result of calculation meets operation condition, bus protection action.
As shown in Fig. 2, the protective device of each element gathers electric current electricity by cable connection routine transformer in 35kV busbares
Analog signals are pressed, internal digital signal are converted to by analog quantity/digital quantity conversion plug-in unit, internal digital signal is turned by communication
It inserts part and is converted to IEC 61850-9-2 digital signals.
The protective device of each element realizes the input and output in this interval by cable connection switching mechanism in 35kV busbares
Analog signals are converted to GOOSE digital signals by communicating conversion plug-in unit.
The protective device of each element is connect transformed IEC 61850-9-2 and GOOSE data by optical cable in 35kV busbares
Enter process-level network, optical cable herein is 100,000,000 optical Ethernets.
Protection equipment for transformer obtains each element in 35kV busbares by a gigabit luminiferous ether network interface access procedure layer network
Current sample instantaneous value and input and output information.
Process-level network possesses 100,000,000 luminiferous ether network interfaces and gigabit luminiferous ether network interface.
Protection equipment for transformer 35kV ratiometric dynamic formulas bus protection is using the split-phase current difference for possessing ratio-restrained characteristic
Dynamic algorithm, calculates the difference stream of all elements on busbar, and operation equation is：
Id>Is
Id>KIr
Wherein：
I in formuladFor difference current；IrFor stalling current；K is ratio brake coefficient；ISFor difference current definite value；To be each
Loop current, operation curve are as shown in Figure 3.
Protection equipment for transformer 35kV ratiometric dynamic formulas bus protection configures Sudden Changing Rate ratio brake differential protection function, with
The conventional ratio brake differential protection that restraint coefficient is fixed as 0.3 is used cooperatively.
Sudden Changing Rate ratio brake differential protection, operation equation are：
Id>0.3Ir
△Id>Is
△Id>0.7△Ir
Wherein：IsFor differential definite value；(For the electric current of j-th of connecting element
Sudden Changing Rate)。
To sum up, 35kV line protective devices obtain current value by cable connection mutual inductor, pass through cable connection breaker
Obtain breaker mechanism information.35kV line protective devices communication conversion plug-in unit, which is converted to current value analog quantity, meets IEC
Breaker mechanism information is converted to the digital signal for meeting GOOSE stipulations, by 100,000,000 by the digital signal of 61850-9-2 standards
Luminiferous ether network interface access procedure layer network.Protection equipment for transformer is by gigabit luminiferous ether network interface access procedure layer network, from network
The upper current value for obtaining all circuit elements on 35kV busbares.Protection equipment for transformer 35kV ratiometric dynamic formulas bus protection configures
Sudden Changing Rate ratio brake differential protection function is fixed as 0.3 conventional ratio brake differential protection with restraint coefficient and is used cooperatively,
Main transformer low-pressure side inlet wire current, 5 35kV line currents are calculated according to above-mentioned formula, i.e.,：
Id>Is
Id>KIr
Wherein：
I in formuladFor difference current；IrFor stalling current；K is ratio brake coefficient；ISFor difference current definite value；To be each
Loop current.
Sudden Changing Rate ratio brake differential protection, operation equation are：
Id>0.3Ir
△Id>Is
△Id>0.7△Ir
Wherein：IsFor differential definite value；(For the electric current of j-th of connecting element
Sudden Changing Rate)。
After result of calculation is met the requirements, GOOSE trip signals are sent, pass through 5 35kV circuits of process-level network tripping
Breaker and main transformer low-pressure side breaker cut off bus-bar fault.
In this embodiment, 35kV ratiometrics dynamic formula bus protection can gather the electric current of all elements on 35kV busbares
Value so as to realize low-voltage bus bar defencive function using the ratiometric dynamic formula differential principle that reliability is high, quick-action is high, solves
Existing 35kV bus protections principle is simple, reliability is low, quick-action is low, it is of high cost, realize the problem of complicated.
Specific embodiment is presented above, but the present invention is not limited to described embodiment.The base of the present invention
This thinking is above-mentioned basic scheme, and for those of ordinary skill in the art, various changes are designed in introduction according to the present invention
The model of shape, formula, parameter simultaneously need not spend creative work.It is right without departing from the principles and spirit of the present invention
The change, modification, replacement and modification that embodiment carries out are still fallen in protection scope of the present invention.
Claims (4)
1. a kind of 35kV and following voltage class ratiometric dynamic formula bus bar protecting method, which is characterized in that the ratiometric dynamic formula
Bus bar protecting method comprises the following steps：
1) in .35kV and following voltage class busbar the protective device of each element gather the current and voltage signals at this interval and open into
Signal is outputed, by being exported with the relevant network interface of optical cable to process-level network, the protective device function of each element is constant；
2) current and voltage signals of protection equipment for transformers receive process layer network and input and output signal calculate institute on busbar
There are the difference stream of element, after result of calculation meets operation condition, bus protection action；
It is flowed using following operation equation to calculate the difference of all elements on busbar：
Id＞ Is
Id＞ KIr
Wherein：
I in formuladFor difference current；IrFor stalling current；K is ratio brake coefficient；ISFor difference current definite value；For each circuit
Electric current；
Protection equipment for transformer 35kV and following voltage class ratiometric dynamic formula bus protection configuration Sudden Changing Rate ratio brake are differential
Defencive function is fixed as 0.3 conventional ratio brake differential protection with restraint coefficient and is used cooperatively；The Sudden Changing Rate ratio brake
Differential protection, operation equation are：
Id＞ 0.3Ir
ΔId＞ Is
ΔId0.7 Δ I of ＞r
Wherein： For the jump-value of current of j-th of connecting element
2. 35kV according to claim 1 and following voltage class ratiometric dynamic formula bus bar protecting method, which is characterized in that
The current and voltage signals are analog signals, and are converted to IEC 61850-9-2 digital signals.
3. 35kV according to claim 2 and following voltage class ratiometric dynamic formula bus bar protecting method, which is characterized in that
The input and output signal is analog signals, and is converted to GOOSE digital signals.
4. 35kV according to claim 3 and following voltage class ratiometric dynamic formula bus bar protecting method, which is characterized in that
The network interface is 100,000,000 luminiferous ether network interfaces；The IEC 61850-9-2 and GOOSE digital signals, pass through 100,000,000 luminiferous ethers
Network interface access procedure layer network.
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| CN201410581407.8A CN105024356B (en) | 2014-06-19 | 2014-10-24 | A kind of 35kV and following voltage class ratiometric dynamic formula bus bar protecting method |
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| CN201410275768X | 2014-06-19 | ||
| CN201410275768 | 2014-06-19 | ||
| CN201410581407.8A CN105024356B (en) | 2014-06-19 | 2014-10-24 | A kind of 35kV and following voltage class ratiometric dynamic formula bus bar protecting method |
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| CN105024356B true CN105024356B (en) | 2018-05-29 |
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106410763B (en) * | 2016-06-28 | 2018-09-21 | 国网江苏省电力公司无锡供电公司 | Integrated distribution website institute relay protection system |
| CN105939006B (en) * | 2016-06-28 | 2018-09-21 | 国网江苏省电力公司无锡供电公司 | The integrated distribution website institute relay protection system of dual power supply |
| CN105958449B (en) * | 2016-06-28 | 2018-06-08 | 国网江苏省电力公司无锡供电公司 | Distribution website institute integrated form relay protection system |
| CN106356822B (en) * | 2016-10-10 | 2019-02-05 | 许继集团有限公司 | A kind of deficient range combinations formula guard method of half-wave power transmission route and device |
| CN107681639B (en) * | 2017-09-26 | 2019-11-12 | 南京国电南自电网自动化有限公司 | A kind of site bus protection relay system and its guard method |
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| CN1725591A (en) * | 2005-07-20 | 2006-01-25 | 北京四方继保自动化股份有限公司 | Adaptive regulation method of bus protection ratio brake coefficient based on bus connection current |
| CN101719696A (en) * | 2009-12-21 | 2010-06-02 | 中国电力科学研究院 | Centralized bus protection device and method applied to digitized transformer station |
| CN102005738A (en) * | 2010-12-15 | 2011-04-06 | 国网电力科学研究院 | Method for identifying healthy phase saturation based on current amplitude ratio and differential current harmonic wave |
| CN102882188A (en) * | 2012-08-10 | 2013-01-16 | 国电南瑞科技股份有限公司 | Centralized digital 35kV single-bus unit protection measurement and control system for 500kv substation |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102611086B (en) * | 2012-03-27 | 2015-01-07 | 许继电气股份有限公司 | Centralized protection system and method for region distribution network |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1725591A (en) * | 2005-07-20 | 2006-01-25 | 北京四方继保自动化股份有限公司 | Adaptive regulation method of bus protection ratio brake coefficient based on bus connection current |
| CN101719696A (en) * | 2009-12-21 | 2010-06-02 | 中国电力科学研究院 | Centralized bus protection device and method applied to digitized transformer station |
| CN102005738A (en) * | 2010-12-15 | 2011-04-06 | 国网电力科学研究院 | Method for identifying healthy phase saturation based on current amplitude ratio and differential current harmonic wave |
| CN102882188A (en) * | 2012-08-10 | 2013-01-16 | 国电南瑞科技股份有限公司 | Centralized digital 35kV single-bus unit protection measurement and control system for 500kv substation |
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