CN105958452A - Power grid distributed network protection method and protection device and system - Google Patents
Power grid distributed network protection method and protection device and system Download PDFInfo
- Publication number
- CN105958452A CN105958452A CN201610513923.6A CN201610513923A CN105958452A CN 105958452 A CN105958452 A CN 105958452A CN 201610513923 A CN201610513923 A CN 201610513923A CN 105958452 A CN105958452 A CN 105958452A
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- 238000000034 method Methods 0.000 title claims abstract description 10
- 238000004891 communication Methods 0.000 claims description 28
- 238000005070 sampling Methods 0.000 claims description 25
- 230000001360 synchronised effect Effects 0.000 claims description 4
- 230000035945 sensitivity Effects 0.000 abstract description 3
- 230000005611 electricity Effects 0.000 description 8
- 230000002633 protecting effect Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 239000002131 composite material Substances 0.000 description 2
- 239000013307 optical fiber Substances 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 230000001012 protector Effects 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000002283 diesel fuel Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000002737 fuel gas Substances 0.000 description 1
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
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- Emergency Protection Circuit Devices (AREA)
Abstract
The invention discloses a power grid distributed network protection method and a protection device and a system. Through collecting all currents in a bus bar area of the device to form a bus bar differential protection, when a grounded short circuit fault occurs in the bus bar range, a protection action quickly cuts off handshaking switches at the two sides of main body ring main units; and through collecting the circuit current between adjacent two ring main units to form a circuit current differential protection, when a grounded fault occurs in the circuit, the protection action quickly cuts off the handshaking switches of the adjacent ring main units at the two sides of the fault. Therefore, the power grid network protection is formed, and the protection has full coverage, high reliability and sensitivity; and the power grid distributed network protection method and the protection device and the system disclosed by the invention can be widely applied to various power supply network protection systems.
Description
Technical field
The present invention relates to electrical network and supply electrical domain, particularly relate to a kind of electrical network power supply protection method and guarantor
Protection unit and ring main unit.
Background technology
In intelligent grid, power supply in addition to main electrical network, may also have the two-way storage of dispersed and distributed
Energy power supply and various generation of electricity by new energy power supply are (as photovoltaic, wind-powered electricity generation etc., fuel gas generation, diesel oil are sent out
Electricity), therefore distribution loop trend complex distribution in electrical network, there is uncertainty: each loop is electric
The size and Orientation of stream is often to change, and in its calculation of short-circuit current, it is the most true that impact calculates
Determining cause element is too many, it is impossible to estimation, and therefore conventional current protection definite value cannot be given, the most not
Conventional current can be relied on to protect the defencive function of electrical network of having worked in coordination, and once distribution host returns
There is line fault in road, protection cannot excise fault by correct operation, and the whole network can only be caused to have a power failure,
Reliability is excessively poor.In power distribution network, conventional busbars differential protection and optical fiber differential protective cost are too
Height, configuration complexity, the most various Medium Voltage Switchgear buses are chronically at unprotect state, distribution
Major loop is also impossible to whole wiring optical fiber differential protective, and bus-bar fault or master once occur
Return lead fault, conventional protection devices can not failure judgement point isolated fault, only entirety is stopped
Electricity.
Summary of the invention
In order to solve above-mentioned technical problem, it is an object of the invention to provide one, to have fault accurate
Excision function, there is the supply network guard method of all standing, high reliability and high sensitivity.
In order to solve above-mentioned technical problem, second object of the present invention is to provide a kind of being conducive to
Fault accurately excises the supply network protection of function, all standing, high reliability and high sensitivity
Device.
In order to solve above-mentioned technical problem, third object of the present invention is to provide a kind of above-mentioned guarantor
The protection system of protection unit.
The technical solution adopted in the present invention is:
A kind of electrical network distributed network protection method, including step:
S1, presets the differential protection setting valve of multiple circuit；
S2, gathers supply network multiple line current instantaneous sampling value；
S3, the line current instantaneous sampling value gathered according to step S2, calculate each line
The difference current instantaneous sampling value on road, calculates difference current virtual value the most accordingly,
By whole to the difference current virtual value between each circuit and the differential protection in step S1
Definite value compares, it is judged that circuit whether fault；
S4, disengagement failure circuit switchs accordingly.
Preferably, described step S1 is particularly as follows: according to each phase of all circuits of bus in ring main unit
Electric current instantaneous sampling value sum is zero, cable run both sides electric current instantaneous sampling value sum is zero former
Reason sets differential protection setting valve；Described step S2 is particularly as follows: synchronous acquisition ring main unit region
Multiple line current instantaneous sampling values；Described step S3 is particularly as follows: gathered according to step S2
Line current instantaneous sampling value, calculate the difference current instantaneous sampling value of each circuit, so
After calculate difference current virtual value accordingly, such as each phase differential current of all circuits of bus in ring main unit
Streaming current virtual value is more than or equal to differential protection setting valve, then judge busbar short-circuit；As
Cable run both sides difference current virtual value is more than or equal to differential protection setting valve, then judge ring
Between net cabinet, circuit is short-circuited fault；Described step S4 is particularly as follows: step S3 is as judged to send out
Rhizoma Anemarrhenae's line short trouble, then cut off ring main unit internal fault both sides and shake hands switch；Step S3 is such as sentenced
Between disconnected ring main unit, circuit is short-circuited fault, then the shaking hands of the adjacent ring main unit in disengagement failure both sides
Switch.
A kind of electrical network distributed network protection device, including: protection control unit, it is used for receiving
The current value that multiple local control units gather, and control local control unit execution tripping action；Multiple existing
Ground unit, described local control unit includes line current harvester and controls killer switch dress
Putting, described current collecting device is used for gathering circuit current value, and described control killer switch fills
Put for performing tripping action according to the order of protection control unit.
Preferably, between described protection control unit and multiple local control unit by Ethernet even
Connect.
Preferably, described control circuit breaker switch device is relay.
Preferably, described protection control unit also includes wireless communication module, described radio communication
Module is for being connected with external equipment.
Preferably, described wireless communication module is GPRS wireless communication module, 3G/4G is wireless
Communication module or WIFI wireless communication module.
A kind of protection system being applied to electrical network distributed network, including multiple rings being sequentially connected with
Net cabinet, described ring main unit is provided with the electrical network distribution as described in any one of claim 3 to 7
Formula network protector.
Preferably, it is connected with each other between the protection control unit of adjacent ring main unit.
Preferably, also include that distribution control center, described protection control unit all pass through radio communication mold
Block is connected with distribution control center.
The invention has the beneficial effects as follows:
The present invention constitutes bus differential protecting by gathering all electric currents of this equipment bus-bar area,
When there is ground short circuit fault in bus ranges, protection act quickly excises body ring main unit two
" shake hands " switch in side；By gathering the line current between adjacent two ring main units, constitute line
Road current differential protection, when circuit generation earth fault, protection act quickly excises fault two
The adjacent ring main unit in side " is shaken hands " switch.Thus constituting electricity grid network protection, its protection has complete
Spreadability, high reliability and susceptiveness.
The composite can be widely applied to various supply network protection system.
Accompanying drawing explanation
Below in conjunction with the accompanying drawings the detailed description of the invention of the present invention is described further:
Fig. 1 is the electrical block diagram of a kind of embodiment of protection device of the present invention；
Fig. 2 is present system one embodiment normal operating conditions schematic diagram；
Fig. 3 is busbar short-circuit fault schematic diagram in present system generation ring main unit；
Fig. 4 is line short fault schematic diagram between present system generation ring main unit.
Detailed description of the invention
It should be noted that in the case of not conflicting, the embodiment in the application and embodiment
In feature can be mutually combined.
A kind of electrical network distributed network protection device, including: protection control unit, it is used for receiving
The current value that multiple local control units gather, and control local control unit execution tripping action；Multiple existing
Ground unit, described local control unit includes line current harvester and controls killer switch dress
Putting, described current collecting device is used for gathering circuit current value, and described control killer switch fills
Put for performing tripping action according to the order of protection control unit.
Preferably, between described protection control unit and multiple local control unit by Ethernet even
Connect.
Preferably, described control circuit breaker switch device is relay.
Preferably, described protection control unit also includes wireless communication module, described radio communication
Module is for being connected with external equipment.
Preferably, described wireless communication module is GPRS wireless communication module, 3G/4G is wireless
Communication module or WIFI wireless communication module.
A kind of protection system being applied to electrical network distributed network, including multiple rings being sequentially connected with
Net cabinet, described ring main unit is provided with the electrical network distribution as described in any one of claim 3 to 7
Formula network protector.
Preferably, it is connected with each other between the protection control unit of adjacent ring main unit.
Preferably, also include that distribution control center, described protection control unit all pass through radio communication mold
Block is connected with distribution control center.
As it is shown in figure 1, as a example by the micro-grid system with multiple ring main unit, detail system group
Become.
Element 1: protection control unit
Protection control unit 1 is connected with data/address bus 2, and bus is connected with all local control units 3
Connecing, protection control unit 1 controls all local control units 3 by data/address bus 2 and realizes synchronization and adopt
Sample, and receive portion's sampled data information；Wherein, data/address bus 2 is industry ethernet.
Whole sampled data information (current value) that protection control unit 1 will be collected, for structure
Build this ring main unit bus differential protecting；
Between adjacent two ring main units as a example by connection line differential protection, protect control unit 1
Carried out with the protection control unit being installed on adjacent ring main unit by radio communication or fiber optic communication
Communication, controls local control unit 3 and the cable that connects between two ring main units is carried out the synchronization of current value
Sampling, within sample-synchronous required precision reaches 10 microseconds, collects both sides, connecting cable road
Current sample Value Data, constitute line differential protection；Protection control unit 1 is judging occur
After short trouble, the local control unit 3 that tripping operation (roof-cut resistence) instruction flows to preset is performed
Tripping operation.In like manner after bus differential protecting action, this ring main unit of tripping 2 " switch of shaking hands "；
Between ring main unit after the line differential protection action of cable run, two adjacent looped networks of tripping
Cabinet and " switch of shaking hands " of cable connection.
Protection control unit 1 is by GPRS public network communication (wireless communication module) and auxiliary tone
The heart sets up contact, after any protection act, i.e. protection act information is reported to scheduling.
Element 2: data communication bus
Data/address bus 2 is all local control unit 3 Hes in connecting a ring main unit or controller switching equipment unit
One protection control unit 1, for ethernet line.Local control unit is divided by number of switches in ring main unit
Dissipate and configure, generally 4,6,8,12.
Element 3: local control unit
Local control unit 3 is connected with data communication bus 2, by bus and protection control unit phase
Connection；
In 3 collection ring main units of 1 local control unit, the three-phase electricity flow valuve of a circuit, only passes through
One relay exports a tripping operation contact to the control circuit breaker switch device of this circuit；
The quantity of 1 ring main unit configuration now device 3 is determined by number of switches (feeder number),
It is distributed, generally 4,6,8,12, is not limited by quantity.
A kind of electrical network distributed network protection method, including step: S1, presets multiple line
The differential protection setting valve on road；S2, gathers supply network multiple line current instantaneous sampling value；
S3, the line current instantaneous sampling value gathered according to step S2, calculate each circuit
Difference current instantaneous sampling value, calculates difference current virtual value the most accordingly, by each circuit
Between difference current virtual value and differential protection setting valve in step S1 compare, it is judged that
Circuit whether fault；S4, disengagement failure circuit switchs accordingly.
Preferably, described step S1 is particularly as follows: according to each phase of all circuits of bus in ring main unit
Electric current instantaneous sampling value sum is zero, cable run both sides electric current instantaneous sampling value sum is zero former
Reason sets differential protection setting valve；Described step S2 is particularly as follows: synchronous acquisition ring main unit region
Multiple line current instantaneous sampling values；Described step S3 is particularly as follows: gathered according to step S2
Line current instantaneous sampling value, calculate the difference current instantaneous sampling value of each circuit, so
After calculate difference current virtual value accordingly, such as each phase differential current of all circuits of bus in ring main unit
Streaming current virtual value is more than or equal to differential protection setting valve, then judge busbar short-circuit；As
Cable run both sides difference current virtual value is more than or equal to differential protection setting valve, then judge ring
Between net cabinet, circuit is short-circuited fault；Described step S4 is particularly as follows: step S3 is as judged to send out
Rhizoma Anemarrhenae's line short trouble, then cut off ring main unit internal fault both sides and shake hands switch；Step S3 is such as sentenced
Between disconnected ring main unit, circuit is short-circuited fault, then the shaking hands of the adjacent ring main unit in disengagement failure both sides
Switch.
Of the present invention operation principle is explained in detail below.
As in figure 2 it is shown, include No. 1 to 3 ring net cabinet, control circuit breaker switch device 12,
21,22,23,24,31, utilize multiple current collecting device synchronous acquisition current value I respectively12、
I21、I22、I31。
If we specify: the electric current flowing into switch cubicle is just, then the electric current flowing out switch cubicle is
Negative.
Can husband's current law according to Cauchy:
Under normal operation or during external fault, bus all line currents sum in ring main unit
Be zero (sampled value sum or vector sum are zero), cable run both sides electric current sum is zero (to adopt
Sample value sum or vector sum are zero).
For having in ring main unit:
For circuit between ring main unit: I12-I21=0, I22-I31=0；
When there is busbar short-circuit, its electric current and be short circuit current Ik。
For ring main unit:
For circuit between ring main unit: I12-I21=0, I22-I31=0；
During the fault that is short-circuited between ring main unit circuit, circuit both sides difference between currents is short circuit electricity
Stream Ik。
For ring main unit:
For circuit between ring main unit: I12-I21=IK、I22-I31=0；
And the short circuit current of minimum is all far longer than on circuit the maximum load current run, therefore
The most thus constitute bus differential protection and Line Current Differential Protection.
Bus differential protecting and Line Current Differential Protection meet relational expression:
ID=∑ I >=ISET
In formula
IDFor difference current；∑ I is bus current sum or line current sum；ISETFor in advance
If differential protection setting valve.
Applicating example
As it is shown on figure 3, when No. 2 ring main unit bus generation earth faults, in above-mentioned Protection criteria,
Only No. 2 ring main unit protection control units judge bus-bar fault, then cutting-off controlling killer switch
Device 21 and 22, No. 1 is not affected normal work by short trouble with 3 ring net cabinet.
As shown in Figure 4, between No. 1 ring main unit and No. 2 ring main units, cable run breaks down,
In upper Protection criteria, line fault on the right side of No. 1 ring main unit protected location judgement, then cut off now
Circuit event on the left of 12, No. 2 ring main unit protected locations judgements of the control circuit breaker switch device of unit
Barrier, then cut off the control circuit breaker switch device 21 of local control unit, due to fault by effectively every
From, the power supply of three ring main units is uninfluenced.
The present invention constitutes bus differential protecting by gathering all electric currents of this equipment bus-bar area,
When there is ground short circuit fault in bus ranges, protection act quickly excises body ring main unit two
" shake hands " switch in side；By gathering the line current between adjacent two ring main units, constitute line
Road current differential protection, when circuit generation earth fault, protection act quickly excises fault two
The adjacent ring main unit in side " is shaken hands " switch.Thus constituting electricity grid network protection, its protection has complete
Spreadability, high reliability and susceptiveness.
The composite can be widely applied to various supply network protection system.
It is above the preferably enforcement of the present invention is illustrated, but the invention is not limited to
Described embodiment, those of ordinary skill in the art are going back on the premise of spirit of the present invention
Can make all equivalent variations or replacement, the deformation of these equivalents or replacement are all contained in this
In application claim limited range.
Claims (10)
1. an electrical network distributed network protection method, it is characterised in that include step:
S1, presets the differential protection setting valve of multiple circuit；
S2, gathers supply network multiple line current instantaneous sampling value；
S3; the line current instantaneous sampling value gathered according to step S2; calculate the difference current instantaneous sampling value of each circuit; calculate difference current virtual value the most accordingly; difference current virtual value between each circuit and the differential protection setting valve in step S1 are compared, it is judged that circuit whether fault；
S4, disengagement failure circuit switchs accordingly.
A kind of electrical network distributed network protection method the most according to claim 1, it is characterised in that
Described step S1 particularly as follows: according to all circuits of bus in ring main unit each phase current instantaneous sampling value sum be zero, cable run both sides electric current instantaneous sampling value sum be zero principle set differential protection setting valve；
Described step S2 is particularly as follows: synchronous acquisition ring main unit region multiple line current instantaneous sampling value；
Described step S3 is particularly as follows: the line current instantaneous sampling value that gathered according to step S2; calculate the difference current instantaneous sampling value of each circuit; calculate difference current virtual value the most accordingly; as in ring main unit, all circuits of bus each phase current differential current effective value more than or equal to differential protection setting valve, then judges busbar short-circuit；If cable run both sides difference current virtual value is more than or equal to differential protection setting valve, then judge between ring main unit that circuit is short-circuited fault；
Described step S4 particularly as follows: step S3 is as judged to occur busbar short-circuit fault, is then cut off ring main unit internal fault both sides and is shaken hands switch；As judged between ring main unit, circuit is short-circuited fault, the then switch of shaking hands of the adjacent ring main unit in disengagement failure both sides step S3.
3. an electrical network distributed network protection device, it is characterised in that including:
Protection control unit, for receiving the current value that multiple local control unit gathers, and controls local control unit execution tripping action；
Multiple local control units; described local control unit includes line current harvester and controls circuit breaker switch device; described current collecting device is used for gathering circuit current value, and described control circuit breaker switch device is for performing tripping action according to the order of protection control unit.
A kind of electrical network distributed network protection device the most according to claim 3, it is characterised in that connected by Ethernet between described protection control unit and multiple local control unit.
A kind of electrical network distributed network protection device the most according to claim 4, it is characterised in that described control circuit breaker switch device is relay.
6., according to a kind of electrical network distributed network protection device described in any one of claim 3 to 5, it is characterised in that described protection control unit also includes wireless communication module, described wireless communication module is for being connected with external equipment.
A kind of electrical network distributed network protection device the most according to claim 6, it is characterised in that described wireless communication module is GPRS wireless communication module, 3G/4G wireless communication module or WIFI wireless communication module.
8. the protection system being applied to electrical network distributed network, it is characterised in that include multiple ring main unit being sequentially connected with, described ring main unit is provided with the electrical network distributed network protection device as described in any one of claim 3 to 7.
A kind of protection system being applied to electrical network distributed network the most according to claim 8, it is characterised in that be connected with each other between the protection control unit of adjacent ring main unit.
A kind of protection system being applied to electrical network distributed network the most according to claim 8 or claim 9, it is characterised in that also include that distribution control center, described protection control unit are all connected with distribution control center by wireless communication module.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610513923.6A CN105958452A (en) | 2016-06-30 | 2016-06-30 | Power grid distributed network protection method and protection device and system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610513923.6A CN105958452A (en) | 2016-06-30 | 2016-06-30 | Power grid distributed network protection method and protection device and system |
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| Publication Number | Publication Date |
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| CN105958452A true CN105958452A (en) | 2016-09-21 |
Family
ID=56903005
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| CN201610513923.6A Pending CN105958452A (en) | 2016-06-30 | 2016-06-30 | Power grid distributed network protection method and protection device and system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112636191A (en) * | 2020-12-08 | 2021-04-09 | 科誉德电气（苏州）有限公司 | Novel looped netowrk cabinet intelligence is synthesized and is observed and controled device design |
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| CN102255388A (en) * | 2011-07-18 | 2011-11-23 | 航天科工深圳（集团）有限公司 | Distributed distribution network terminal device |
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